Update CHANGELOG

Add optional config for gasPrice and gasLimit for every transaction sending method

.circleci/config.yml

@@ -0,0 +1,28 @@
+version: 2
+
+jobs:
+  build:
+    docker:
+      - image: circleci/node:6.12
+    environment:
+      CONTRACTS_COMMIT_HASH: '78fe8dd'
+    steps:
+      - checkout
+      - run: echo 'export PATH=$HOME/CIRCLE_PROJECT_REPONAME/node_modules/.bin:$PATH' >> $BASH_ENV
+      - run:
+          name: yarn
+          command: yarn
+      - save_cache:
+          key: dependency-cache-{{ checksum "package.json" }}
+          paths:
+            - ~/.cache/yarn
+      - run: wget https://s3.amazonaws.com/testrpc-shapshots/${CONTRACTS_COMMIT_HASH}.zip
+      - run: unzip ${CONTRACTS_COMMIT_HASH}.zip -d testrpc_snapshot
+      - run: node ./node_modules/lerna/bin/lerna.js bootstrap
+      - run: yarn lerna:run bootstrap
+      - run:
+          name: testrpc
+          command: npm run testrpc -- --db testrpc_snapshot
+          background: true
+      - run: yarn lerna:run test:circleci
+      - run: yarn lerna:run lint

.gitignore

@@ -58,9 +58,13 @@ typings/
 .env
 
 # built library using in commonjs module syntax
-lib
+lib/
 # UMD bundles that export the global variable
 _bundles
 
 # generated documentation
-docs
+generated_docs/
+
+TODO.md
+
+packages/website/public/bundle*

README.md

@@ -4,50 +4,25 @@
 
 [0x][website-url] is an open protocol that facilitates trustless, low friction exchange of Ethereum-based assets. A full description of the protocol may be found in our [whitepaper][whitepaper-url].
 
-This repository contains a Javascript library that makes it easy to build Relayers and other DApps that use the 0x protocol.
+This repository contains all the 0x developer tools written in TypeScript. Our hope is that these tools make it easy to build Relayers and other DApps that use the 0x protocol.
+
+[website-url]: https://0xproject.com/
+[whitepaper-url]: https://0xproject.com/pdfs/0x_white_paper.pdf
 
 [![CircleCI](https://circleci.com/gh/0xProject/0x.js.svg?style=svg&circle-token=61bf7cd8c9b4e11b132089dfcffdd1be277d1e0c)](https://circleci.com/gh/0xProject/0x.js)
-[![npm version](https://badge.fury.io/js/0x.js.svg)](https://badge.fury.io/js/0x.js)
 [![Coverage Status](https://coveralls.io/repos/github/0xProject/0x.js/badge.svg?branch=master&t=fp0cXD)](https://coveralls.io/github/0xProject/0x.js?branch=master)
-[![Slack Status](http://slack.0xProject.com/badge.svg)](http://slack.0xProject.com)
+[![Discord](https://img.shields.io/badge/chat-rocket.chat-yellow.svg?style=flat
+)](https://chat.0xproject.com)
 [![Join the chat at https://gitter.im/0xProject/Lobby](https://badges.gitter.im/0xProject/Lobby.svg)](https://gitter.im/0xProject/Lobby?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 [![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)
 [![Greenkeeper badge](https://badges.greenkeeper.io/0xProject/0x.js.svg?token=7c22e5c72acf39d3ead8d29c5d9bb38f9096df3e643024dcedd53ab732847be1&ts=1496426342666)](https://greenkeeper.io/)
 
-## Installation
+### Core Packages
 
-0x.js ships as both a [UMD](https://github.com/umdjs/umd) module and a [CommonJS](https://en.wikipedia.org/wiki/CommonJS) package.
-
-#### CommonJS *(recommended)*:
-
-**Install**
-
-```bash
-npm install 0x.js --save
-```
-
-**Import**
-
-```javascript
-import {ZeroEx} from '0x.js';
-```
-
-#### UMD:
-
-**Install**
-
-Download the UMD module from our [releases page](https://github.com/0xProject/0x.js/releases) and add it to your project.
-
-**Import**
-
-```html
-<script type="text/javascript" src="0x.js"></script>
-```
-
-## Documentation
-
-Extensive documentation of 0x.js can be found on [our website][docs-url].
-
-[website-url]: https://0xproject.com/
-[whitepaper-url]: https://0xproject.com/pdfs/0x_white_paper.pdf
-[docs-url]: https://0xproject.com/docs/0xjs
+| Package | Version | Description |
+|--------|-------|------------|
+| [`0x.js`](/packages/0x.js) | [![npm](https://img.shields.io/npm/v/0x.js.svg?maxAge=2592000)](https://www.npmjs.com/package/0x.js) | A Javascript library for interacting with the 0x protocol |
+| [`@0xproject/assert`](/packages/assert) | [![npm](https://img.shields.io/npm/v/@0xproject/assert.svg?maxAge=2592000)](https://www.npmjs.com/package/@0xproject/assert) | Standard type and schema assertions |
+| [`@0xproject/connect`](/packages/connect) | [![npm](https://img.shields.io/npm/v/@0xproject/connect.svg?maxAge=2592000)](https://www.npmjs.com/package/@0xproject/connect) | A Javascript library for interacting with the standard relayer api |
+| [`@0xproject/json-schemas`](/packages/json-schemas) | [![npm](https://img.shields.io/npm/v/@0xproject/json-schemas.svg?maxAge=2592000)](https://www.npmjs.com/package/@0xproject/json-schemas) | 0x-related json schemas |
+| [`@0xproject/tslint-config`](/packages/tslint-config) | [![npm](https://img.shields.io/npm/v/@0xproject/tslint-config.svg?maxAge=2592000)](https://www.npmjs.com/package/@0xproject/tslint-config) | Custom 0x project TSLint rules |

circle.yml

@@ -1,23 +0,0 @@
-machine:
-  node:
-    version: 6.5.0
-  environment:
-      CONTRACTS_COMMIT_HASH: '35053f9'
-      PATH: "${PATH}:${HOME}/${CIRCLE_PROJECT_REPONAME}/node_modules/.bin"
-
-dependencies:
-  override:
-    - yarn
-  cache_directories:
-    - ~/.cache/yarn
-
-test:
-  override:
-    - wget https://s3.amazonaws.com/testrpc-shapshots/${CONTRACTS_COMMIT_HASH}.zip
-    - unzip ${CONTRACTS_COMMIT_HASH}.zip -d testrpc_snapshot
-    - npm run testrpc -- --db testrpc_snapshot:
-        background: true
-    - yarn test:coverage
-    - yarn report_test_coverage
-    - if [ $CIRCLE_BRANCH = "master" ]; then yarn test:umd; fi
-    - yarn lint

lerna.json

@@ -0,0 +1,9 @@
+{
+  "lerna": "2.5.1",
+  "packages": [
+    "packages/*"
+  ],
+  "version": "independent",
+  "npmClient": "yarn",
+  "useWorkspaces": true
+}

package.json

@@ -1,104 +1,22 @@
 {
-  "name": "0x.js",
-  "version": "0.20.0",
-  "description": "A javascript library for interacting with the 0x protocol",
-  "keywords": [
-    "0x.js",
-    "0xproject",
-    "ethereum",
-    "tokens",
-    "exchange"
-  ],
-  "main": "lib/src/index.js",
-  "types": "lib/src/index.d.ts",
-  "scripts": {
-    "prebuild": "npm run clean",
-    "build": "run-p build:umd:prod build:commonjs",
-    "prepublishOnly": "run-p build",
-    "postpublish": "run-s release docs:json upload_docs_json",
-    "release": "publish-release --assets _bundles/index.js,_bundles/index.min.js --tag $(git describe --tags) --owner 0xProject --repo 0x.js",
-    "upload_docs_json": "aws s3 cp docs/index.json s3://0xjs-docs-jsons/$(git describe --tags).json --profile 0xproject --grants read=uri=http://acs.amazonaws.com/groups/global/AllUsers --content-type aplication/json",
-    "lint": "tslint src/*.ts test/*.ts",
-    "test": "run-s clean test:commonjs",
-    "test:umd": "./scripts/test_umd.sh",
-    "test:coverage": "nyc npm run test --all",
-    "report_test_coverage": "nyc report --reporter=text-lcov | coveralls",
-    "update_contracts": "for i in ${npm_package_config_artifacts}; do copyfiles -u 4 ../contracts/build/contracts/$i.json ../0x.js/src/artifacts; done;",
-    "testrpc": "testrpc -p 8545 --networkId 50 -m \"${npm_package_config_mnemonic}\"",
-    "docs:json": "typedoc --excludePrivate --excludeExternals --target ES5 --json docs/index.json .",
-    "docs:generate": "typedoc --out docs .",
-    "docs:open": "opn docs/index.html",
-    "clean": "shx rm -rf _bundles lib test_temp",
-    "build:umd:dev": "webpack",
-    "build:umd:prod": "NODE_ENV=production webpack",
-    "build:commonjs": "tsc; copyfiles -u 2 './src/artifacts/**/*.json' ./lib/src/artifacts;",
-    "test:commonjs": "run-s build:commonjs run_mocha",
-    "pretest:umd": "run-s clean build:umd:dev build:commonjs",
-    "substitute_umd_bundle": "npm run remove_src_files_not_used_by_tests; shx mv _bundles/* lib/src",
-    "remove_src_files_not_used_by_tests": "find ./lib/src \\( -path ./lib/src/utils -o -path ./lib/src/subproviders -o -path ./lib/src/schemas -o -path \"./lib/src/types.*\" \\) -prune -o -type f -print | xargs rm",
-    "run_mocha": "mocha lib/test/**/*_test.js --timeout 5000 --bail --exit"
-  },
-  "config": {
-    "artifacts": "TokenTransferProxy Exchange TokenRegistry Token EtherToken",
-    "mnemonic": "concert load couple harbor equip island argue ramp clarify fence smart topic"
-  },
-  "repository": {
-    "type": "git",
-    "url": "https://github.com/0xProject/0x.js"
-  },
-  "license": "Apache-2.0",
-  "engines": {
-    "node": ">=6.0.0"
-  },
-  "devDependencies": {
-    "@types/jsonschema": "^1.1.1",
-    "@types/lodash": "^4.14.64",
-    "@types/mocha": "^2.2.41",
-    "@types/node": "^8.0.1",
-    "@types/sinon": "^2.2.2",
-    "awesome-typescript-loader": "^3.1.3",
-    "bignumber.js": "^4.0.2",
-    "chai": "^4.0.1",
-    "chai-as-promised": "^7.1.0",
-    "chai-as-promised-typescript-typings": "0.0.3",
-    "chai-bignumber": "^2.0.1",
-    "chai-typescript-typings": "^0.0.0",
-    "copyfiles": "^1.2.0",
-    "coveralls": "^3.0.0",
-    "dirty-chai": "^2.0.1",
-    "ethereumjs-testrpc": "4.0.1",
-    "json-loader": "^0.5.4",
-    "mocha": "^4.0.0",
-    "npm-run-all": "^4.0.2",
-    "nyc": "^11.0.1",
-    "opn-cli": "^3.1.0",
-    "request": "^2.81.0",
-    "request-promise-native": "^1.0.4",
-    "shx": "^0.2.2",
-    "sinon": "^4.0.0",
-    "source-map-support": "^0.5.0",
-    "truffle-hdwallet-provider": "^0.0.3",
-    "tslint": "^5.3.2",
-    "tslint-config-0xproject": "^0.0.2",
-    "typedoc": "^0.8.0",
-    "types-bn": "^0.0.1",
-    "types-ethereumjs-util": "0xProject/types-ethereumjs-util",
-    "typescript": "^2.4.1",
-    "web3-provider-engine": "^13.0.1",
-    "web3-typescript-typings": "^0.6.2",
-    "webpack": "^3.1.0"
-  },
-  "dependencies": {
-    "@types/bignumber.js": "^4.0.2",
-    "0x-json-schemas": "^0.6.1",
-    "bignumber.js": "^4.0.2",
-    "compare-versions": "^3.0.1",
-    "es6-promisify": "^5.0.0",
-    "ethereumjs-abi": "^0.6.4",
-    "ethereumjs-util": "^5.1.1",
-    "find-versions": "^2.0.0",
-    "lodash": "^4.17.4",
-    "publish-release": "^1.3.3",
-    "web3": "^0.20.0"
-  }
+    "private": true,
+    "name": "0x.js",
+    "workspaces": [
+        "packages/*"
+    ],
+    "scripts": {
+        "testrpc": "testrpc -p 8545 --networkId 50 -m \"${npm_package_config_mnemonic}\"",
+        "lerna:run": "lerna run",
+        "lerna:publish": "lerna run clean; lerna run build; lerna publish --registry=https://registry.npmjs.org/"
+    },
+    "config": {
+      "mnemonic": "concert load couple harbor equip island argue ramp clarify fence smart topic"
+    },
+    "devDependencies": {
+        "lerna": "^2.5.1",
+        "async-child-process": "^1.1.1",
+        "semver-sort": "^0.0.4",
+        "publish-release": "0xproject/publish-release",
+        "es6-promisify": "^5.0.0"
+    }
 }

packages/0x.js/CHANGELOG.md

@@ -1,19 +1,108 @@
 # CHANGELOG
 
-v0.20.0 - _October 3, 2017_
+v0.27.0 - _November 28, 2017_
+------------------------
+    * Make `ZeroExConfig` required parameter of `ZeroEx` constructor (#233)
+    * Add a required property `networkId` to `ZeroExConfig` (#233)
+    * Make all `getContractAddress` functions, `zeroEx.exchange.subscribe`, `zeroEx.exchange.getZRXTokenAddress` sync (#233)
+    * Remove `ZeroExError.ContractNotFound` and replace it with contract-specific errors (#233)
+    * Make `DecodedLogEvent<A>` contain `LogWithDecodedArgs<A>` under log key instead of merging it in like web3 does (#234)
+    * Rename `removed` to `isRemoved` in `DecodedLogEvent<A>` (#234)
+    * Add config allowing to specify gasPrice and gasLimit for every transaction sending method (#235)
+    * All transaction sending methods now call `estimateGas` if no gas amount was supplied (#235)
+    * Modify order validation methods to validate against the `latest` block, not against the `pending` block (#236)
+
+v0.26.0 - _November 21, 2017_
+------------------------
+    * Add post-formatter for logs converting `blockNumber`, `logIndex`, `transactionIndex` from hexes to numbers (#231)
+    * Remove support for Async callback types when used in Subscribe functions (#222)
+    * In OrderWatcher subscribe to ZRX Token Transfer and Approval events when maker token is different (#225)
+
+v0.25.1 - _November 13, 2017_
+------------------------
+    * Standardise on Cancelled over Canceled (#217)
+    * Add missing `DecodedLogEvent` type to exported types (#205)
+    * Normalized the transactionReceipt status to be `null|0|1`, 1 meaning transaction execution successful, 0 unsuccessful and `null` if it is a pre-byzantinium transaction. (#200)
+
+v0.23.0 - _November 12, 2017_
+------------------------
+    * Fixed unhandled promise rejection error in subscribe methods (#209)
+    * Subscribe callbacks now receive an error object as their first argument
+
+v0.22.6 - _November 10, 2017_
+------------------------
+    * Add a timeout parameter to transaction awaiting (#206)
+
+v0.22.5 - _November 7, 2017_
+------------------------
+    * Re-publish v0.22.4 to fix publishing issue
+
+v0.22.4 - _October 25, 2017_
+------------------------
+    * Upgraded bignumber.js to a new version that ships with native typings
+
+v0.22.3 - _October 25, 2017_
+------------------------
+    * Fixed an issue with new version of testrpc and unlimited proxy allowance (#199)
+
+v0.22.2 - _October 24, 2017_
+------------------------
+    * Fixed rounding of maker fill amount and incorrect validation of partial fees (#197)
+
+v0.22.0 - _October 16, 2017_
+------------------------
+    * Started using `OrderFillRequest` interface instead of `OrderFillOrKillRequest` interface for `zeroEx.exchange.batchFillOrKill` (#187)
+    * Removed `OrderFillOrKillRequest` (#187)
+
+v0.21.4 - _October 13, 2017_
+------------------------
+    * Made 0x.js more type-safe by making `getLogsAsync` and `subscribe/subscribeAsync` generics parametrized with arg type (#194)
+
+v0.21.3 - _October 12, 2017_
+------------------------
+    * Fixed a bug causing order fills to throw `INSUFFICIENT_TAKER_ALLOWANCE` (#193)
+
+v0.21.2 - _October 11, 2017_
+------------------------
+    * Exported `ContractEventArg` as a public type (#190)
+
+v0.21.1 - _October 11, 2017_
+------------------------
+    * Fixed a bug in subscriptions (#189)
+
+v0.21.0 - _October 10, 2017_
+------------------------
+    * Complete rewrite of subscription logic (#182)
+        * Subscriptions no longer return historical logs. If you want them - use `getLogsAsync`
+        * Subscriptions now use [ethereumjs-blockstream](https://github.com/ethereumjs/ethereumjs-blockstream) under the hood
+            * Subscriptions correctly handle block re-orgs (forks)
+            * Subscriptions correctly backfill logs (connection problems)
+            * They no longer setup filters on the underlying nodes, so you can use them with infura without a filter Subprovider
+        * Removed `ContractEventEmitter` and added `LogEvent`
+        * Renamed `zeroEx.token.subscribeAsync` to `zeroEx.token.subscribe`
+        * Added `zeroEx.token.unsubscribe` and `zeroEx.exchange.unsubscribe`
+        * Renamed `zeroEx.exchange.stopWatchingAllEventsAsync` to `zeroEx.exhange.unsubscribeAll`
+        * Renamed `zeroEx.token.stopWatchingAllEventsAsync` to `zeroEx.token.unsubscribeAll`
+    * Fixed the batch fills validation by emulating all balance & proxy allowance changes (#185)
+
+v0.20.0 - _October 5, 2017_
+------------------------
     * Add `zeroEx.token.getLogsAsync` (#178)
     * Add `zeroEx.exchange.getLogsAsync` (#178)
     * Fixed fees validation when one of the tokens transferred is ZRX (#181)
 
 v0.19.0 - _September 29, 2017_
+------------------------
     * Made order validation optional  (#172)
     * Added Ropsten testnet support (#173)
     * Fixed a bug causing awaitTransactionMinedAsync to DDos backend nodes (#175)
 
 v0.18.0 - _September 26, 2017_
+------------------------
     * Added `zeroEx.exchange.validateOrderFillableOrThrowAsync` to simplify orderbook pruning (#170)
 
 v0.17.0 - _September 26, 2017_
+------------------------
     * Made `zeroEx.exchange.getZRXTokenAddressAsync` public (#171)
 
 v0.16.0 - _September 20, 2017_

packages/0x.js/README.md

@@ -0,0 +1,40 @@
+0x.js
+-----
+
+## Installation
+
+0x.js ships as both a [UMD](https://github.com/umdjs/umd) module and a [CommonJS](https://en.wikipedia.org/wiki/CommonJS) package.
+
+#### CommonJS *(recommended)*:
+
+**Install**
+
+```bash
+npm install 0x.js --save
+```
+
+**Import**
+
+```javascript
+import {ZeroEx} from '0x.js';
+```
+
+#### UMD:
+
+**Install**
+
+Download the UMD module from our [releases page](https://github.com/0xProject/0x.js/releases) and add it to your project.
+
+**Import**
+
+```html
+<script type="text/javascript" src="0x.js"></script>
+```
+
+## Documentation
+
+Extensive documentation of 0x.js can be found on [our website][docs-url].
+
+[website-url]: https://0xproject.com/
+[whitepaper-url]: https://0xproject.com/pdfs/0x_white_paper.pdf
+[docs-url]: https://0xproject.com/docs/0xjs

packages/0x.js/package.json

@@ -0,0 +1,102 @@
+{
+  "name": "0x.js",
+  "version": "0.26.1",
+  "description": "A javascript library for interacting with the 0x protocol",
+  "keywords": [
+    "0x.js",
+    "0xproject",
+    "ethereum",
+    "tokens",
+    "exchange"
+  ],
+  "main": "lib/src/index.js",
+  "types": "lib/src/index.d.ts",
+  "scripts": {
+    "prebuild": "npm run clean",
+    "build": "run-p build:umd:prod build:commonjs; exit 0;",
+    "docs:json": "typedoc --excludePrivate --excludeExternals --target ES5 --json $JSON_FILE_PATH $PROJECT_DIR",
+    "upload_docs_json": "aws s3 cp generated_docs/index.json $S3_URL --profile 0xproject --grants read=uri=http://acs.amazonaws.com/groups/global/AllUsers --content-type application/json",
+    "lint": "tslint --project . 'src/**/*.ts' 'test/**/*.ts'",
+    "test:circleci": "run-s test:coverage report_test_coverage && if [ $CIRCLE_BRANCH = \"development\" ]; then yarn test:umd; fi",
+    "test": "run-s clean test:commonjs",
+    "test:umd": "./scripts/test_umd.sh",
+    "test:coverage": "nyc npm run test --all",
+    "report_test_coverage": "nyc report --reporter=text-lcov | coveralls",
+    "update_contracts": "for i in ${npm_package_config_artifacts}; do copyfiles -u 4 ../contracts/build/contracts/$i.json ../0x.js/src/artifacts; done;",
+    "clean": "shx rm -rf _bundles lib test_temp",
+    "build:umd:dev": "webpack",
+    "build:umd:prod": "NODE_ENV=production webpack",
+    "build:commonjs": "tsc && copyfiles -u 2 './src/artifacts/**/*.json' ./lib/src/artifacts;",
+    "test:commonjs": "run-s build:commonjs run_mocha",
+    "pretest:umd": "run-s clean build:umd:dev build:commonjs",
+    "substitute_umd_bundle": "shx mv _bundles/* lib/src",
+    "run_mocha": "mocha lib/test/**/*_test.js --timeout 5000 --bail --exit"
+  },
+  "config": {
+    "artifacts": "TokenTransferProxy Exchange TokenRegistry Token EtherToken"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/0xProject/0x.js"
+  },
+  "license": "Apache-2.0",
+  "engines": {
+    "node": ">=6.0.0"
+  },
+  "devDependencies": {
+    "@0xproject/tslint-config": "^0.1.1",
+    "@types/bintrees": "^1.0.2",
+    "@types/jsonschema": "^1.1.1",
+    "@types/lodash": "^4.14.64",
+    "@types/mocha": "^2.2.41",
+    "@types/node": "^8.0.1",
+    "@types/sinon": "^2.2.2",
+    "@types/uuid": "^3.4.2",
+    "awesome-typescript-loader": "^3.1.3",
+    "chai": "^4.0.1",
+    "chai-as-promised": "^7.1.0",
+    "chai-as-promised-typescript-typings": "0.0.3",
+    "chai-bignumber": "^2.0.1",
+    "chai-typescript-typings": "^0.0.1",
+    "copyfiles": "^1.2.0",
+    "coveralls": "^3.0.0",
+    "dirty-chai": "^2.0.1",
+    "ethereumjs-testrpc": "6.0.3",
+    "json-loader": "^0.5.4",
+    "mocha": "^4.0.0",
+    "npm-run-all": "^4.0.2",
+    "nyc": "^11.0.1",
+    "opn-cli": "^3.1.0",
+    "request": "^2.81.0",
+    "request-promise-native": "^1.0.4",
+    "shx": "^0.2.2",
+    "sinon": "^4.0.0",
+    "source-map-support": "^0.5.0",
+    "truffle-hdwallet-provider": "^0.0.3",
+    "tslint": "5.8.0",
+    "typedoc": "~0.8.0",
+    "types-bn": "^0.0.1",
+    "types-ethereumjs-util": "0xProject/types-ethereumjs-util",
+    "typescript": "~2.6.1",
+    "web3-provider-engine": "^13.0.1",
+    "web3-typescript-typings": "^0.7.1",
+    "webpack": "^3.1.0"
+  },
+  "dependencies": {
+    "@0xproject/assert": "^0.0.5",
+    "@0xproject/json-schemas": "^0.6.8",
+    "bignumber.js": "~4.1.0",
+    "bintrees": "^1.0.2",
+    "bn.js": "4.11.8",
+    "compare-versions": "^3.0.1",
+    "es6-promisify": "^5.0.0",
+    "ethereumjs-abi": "^0.6.4",
+    "ethereumjs-blockstream": "^2.0.6",
+    "ethereumjs-util": "^5.1.1",
+    "find-versions": "^2.0.0",
+    "js-sha3": "^0.6.1",
+    "lodash": "^4.17.4",
+    "uuid": "^3.1.0",
+    "web3": "^0.20.0"
+  }
+}

packages/0x.js/scripts/postpublish.js

@@ -0,0 +1,44 @@
+const execAsync = require('async-child-process').execAsync;
+const postpublish_utils = require('../../../scripts/postpublish_utils');
+const packageJSON = require('../package.json');
+
+const cwd = __dirname + '/..';
+const subPackageName = packageJSON.name;
+const S3BucketPath = 's3://0xjs-docs-jsons/';
+
+let tag;
+let version;
+postpublish_utils.getLatestTagAndVersionAsync(subPackageName)
+    .then(function(result) {
+        tag = result.tag;
+        version = result.version;
+         const releaseName = postpublish_utils.getReleaseName(subPackageName, version);
+         const assets = [
+             __dirname + '/../_bundles/index.js',
+             __dirname + '/../_bundles/index.min.js',
+         ];
+         return postpublish_utils.publishReleaseNotes(tag, releaseName, assets);
+    })
+    .then(function(release) {
+        console.log('POSTPUBLISH: Release successful, generating docs...');
+        const jsonFilePath = __dirname + '/../' + postpublish_utils.generatedDocsDirectoryName + '/index.json';
+        return execAsync(
+            'JSON_FILE_PATH=' + jsonFilePath + ' PROJECT_DIR=' + __dirname + '/.. yarn docs:json',
+            {
+                cwd,
+            }
+        );
+    })
+    .then(function(result) {
+        if (result.stderr !== '') {
+            throw new Error(result.stderr);
+        }
+        const fileName = 'v' + version + '.json';
+        console.log('POSTPUBLISH: Doc generation successful, uploading docs... as ', fileName);
+        const s3Url = S3BucketPath + fileName;
+        return execAsync('S3_URL=' + s3Url + ' yarn upload_docs_json', {
+            cwd,
+        });
+    }).catch (function(err) {
+        throw err;
+    });

packages/0x.js/scripts/test_umd.sh

@@ -3,5 +3,4 @@
 # UMD tests should only be run after building the commonjs because they reuse some of the commonjs build artifacts
 run-s substitute_umd_bundle run_mocha
 return_code=$?
-npm run clean
 exit $return_code

packages/0x.js/src/0x.ts

@@ -1,40 +1,35 @@
-import * as _ from 'lodash';
-import * as BigNumber from 'bignumber.js';
-import * as Web3 from 'web3';
-import * as abiDecoder from 'abi-decoder';
-import {SchemaValidator, schemas} from '0x-json-schemas';
-import {bigNumberConfigs} from './bignumber_config';
+import {schemas, SchemaValidator} from '@0xproject/json-schemas';
+import BigNumber from 'bignumber.js';
 import * as ethUtil from 'ethereumjs-util';
-import findVersions = require('find-versions');
-import compareVersions = require('compare-versions');
-import {Web3Wrapper} from './web3_wrapper';
-import {constants} from './utils/constants';
-import {utils} from './utils/utils';
-import {signatureUtils} from './utils/signature_utils';
-import {assert} from './utils/assert';
-import {AbiDecoder} from './utils/abi_decoder';
-import {intervalUtils} from './utils/interval_utils';
+import * as _ from 'lodash';
+
 import {artifacts} from './artifacts';
+import {bigNumberConfigs} from './bignumber_config';
+import {EtherTokenWrapper} from './contract_wrappers/ether_token_wrapper';
 import {ExchangeWrapper} from './contract_wrappers/exchange_wrapper';
 import {TokenRegistryWrapper} from './contract_wrappers/token_registry_wrapper';
-import {EtherTokenWrapper} from './contract_wrappers/ether_token_wrapper';
-import {TokenWrapper} from './contract_wrappers/token_wrapper';
 import {TokenTransferProxyWrapper} from './contract_wrappers/token_transfer_proxy_wrapper';
+import {TokenWrapper} from './contract_wrappers/token_wrapper';
+import {OrderStateWatcher} from './order_watcher/order_state_watcher';
+import {zeroExConfigSchema} from './schemas/zero_ex_config_schema';
 import {
     ECSignature,
-    ZeroExError,
     Order,
+    OrderStateWatcherConfig,
     SignedOrder,
+    TransactionReceiptWithDecodedLogs,
     Web3Provider,
     ZeroExConfig,
-    TransactionReceipt,
-    DecodedLogArgs,
-    TransactionReceiptWithDecodedLogs,
-    LogWithDecodedArgs,
-    FilterObject,
-    RawLog,
+    ZeroExError,
 } from './types';
-import {zeroExConfigSchema} from './schemas/zero_ex_config_schema';
+import {AbiDecoder} from './utils/abi_decoder';
+import {assert} from './utils/assert';
+import {constants} from './utils/constants';
+import {intervalUtils} from './utils/interval_utils';
+import {OrderStateUtils} from './utils/order_state_utils';
+import {signatureUtils} from './utils/signature_utils';
+import {utils} from './utils/utils';
+import {Web3Wrapper} from './web3_wrapper';
 
 // Customize our BigNumber instances
 bigNumberConfigs.configure();
@@ -74,6 +69,11 @@ export class ZeroEx {
      * tokenTransferProxy smart contract.
      */
     public proxy: TokenTransferProxyWrapper;
+    /**
+     * An instance of the OrderStateWatcher class containing methods for watching a set of orders for relevant
+     * blockchain state changes.
+     */
+    public orderStateWatcher: OrderStateWatcher;
     private _web3Wrapper: Web3Wrapper;
     private _abiDecoder: AbiDecoder;
     /**
@@ -89,19 +89,8 @@ export class ZeroEx {
         assert.doesConformToSchema('signature', signature, schemas.ecSignatureSchema);
         assert.isETHAddressHex('signerAddress', signerAddress);
 
-        const dataBuff = ethUtil.toBuffer(data);
-        const msgHashBuff = ethUtil.hashPersonalMessage(dataBuff);
-        try {
-            const pubKey = ethUtil.ecrecover(
-                msgHashBuff,
-                signature.v,
-                ethUtil.toBuffer(signature.r),
-                ethUtil.toBuffer(signature.s));
-            const retrievedAddress = ethUtil.bufferToHex(ethUtil.pubToAddress(pubKey));
-            return retrievedAddress === signerAddress;
-        } catch (err) {
-            return false;
-        }
+        const isValidSignature = signatureUtils.isValidSignature(data, signature, signerAddress);
+        return isValidSignature;
     }
     /**
      * Generates a pseudo-random 256-bit salt.
@@ -109,7 +98,7 @@ export class ZeroEx {
      * and will not collide with other outstanding orders that are identical in all other parameters.
      * @return  A pseudo-random 256-bit number that can be used as a salt.
      */
-    public static generatePseudoRandomSalt(): BigNumber.BigNumber {
+    public static generatePseudoRandomSalt(): BigNumber {
         // BigNumber.random returns a pseudo-random number between 0 & 1 with a passed in number of decimal places.
         // Source: https://mikemcl.github.io/bignumber.js/#random
         const randomNumber = BigNumber.random(constants.MAX_DIGITS_IN_UNSIGNED_256_INT);
@@ -140,7 +129,7 @@ export class ZeroEx {
      * @param   decimals    The number of decimal places the unit amount has.
      * @return  The amount in units.
      */
-    public static toUnitAmount(amount: BigNumber.BigNumber, decimals: number): BigNumber.BigNumber {
+    public static toUnitAmount(amount: BigNumber, decimals: number): BigNumber {
         assert.isBigNumber('amount', amount);
         assert.isNumber('decimals', decimals);
 
@@ -156,7 +145,7 @@ export class ZeroEx {
      * @param   decimals    The number of decimal places the unit amount has.
      * @return  The amount in baseUnits.
      */
-    public static toBaseUnitAmount(amount: BigNumber.BigNumber, decimals: number): BigNumber.BigNumber {
+    public static toBaseUnitAmount(amount: BigNumber, decimals: number): BigNumber {
         assert.isBigNumber('amount', amount);
         assert.isNumber('decimals', decimals);
 
@@ -181,58 +170,48 @@ export class ZeroEx {
      * @param   config      The configuration object. Look up the type for the description.
      * @return  An instance of the 0x.js ZeroEx class.
      */
-    constructor(provider: Web3Provider, config?: ZeroExConfig) {
+    constructor(provider: Web3Provider, config: ZeroExConfig) {
         assert.isWeb3Provider('provider', provider);
-        if (!_.isUndefined(config)) {
-            assert.doesConformToSchema('config', config, zeroExConfigSchema);
-        }
-        if (_.isUndefined((provider as any).sendAsync)) {
-            // Web3@1.0 provider doesn't support synchronous http requests,
-            // so it only has an async `send` method, instead of a `send` and `sendAsync` in web3@0.x.x`
-            // We re-assign the send method so that Web3@1.0 providers work with 0x.js
-            (provider as any).sendAsync = (provider as any).send;
-        }
+        assert.doesConformToSchema('config', config, zeroExConfigSchema);
         const artifactJSONs = _.values(artifacts);
         const abiArrays = _.map(artifactJSONs, artifact => artifact.abi);
         this._abiDecoder = new AbiDecoder(abiArrays);
-        const gasPrice = _.isUndefined(config) ? undefined : config.gasPrice;
         const defaults = {
-            gasPrice,
+            gasPrice: config.gasPrice,
         };
-        this._web3Wrapper = new Web3Wrapper(provider, defaults);
+        this._web3Wrapper = new Web3Wrapper(provider, config.networkId, defaults);
+        this.proxy = new TokenTransferProxyWrapper(
+            this._web3Wrapper,
+            config.tokenTransferProxyContractAddress,
+        );
         this.token = new TokenWrapper(
             this._web3Wrapper,
             this._abiDecoder,
-            this._getTokenTransferProxyAddressAsync.bind(this),
+            this.proxy,
         );
-        const exchageContractAddressIfExists = _.isUndefined(config) ? undefined : config.exchangeContractAddress;
         this.exchange = new ExchangeWrapper(
             this._web3Wrapper,
             this._abiDecoder,
             this.token,
-            exchageContractAddressIfExists,
+            config.exchangeContractAddress,
         );
-        this.proxy = new TokenTransferProxyWrapper(
-            this._web3Wrapper,
-            this._getTokenTransferProxyAddressAsync.bind(this),
+        this.tokenRegistry = new TokenRegistryWrapper(this._web3Wrapper, config.tokenRegistryContractAddress);
+        this.etherToken = new EtherTokenWrapper(this._web3Wrapper, this.token, config.etherTokenContractAddress);
+        this.orderStateWatcher = new OrderStateWatcher(
+            this._web3Wrapper, this._abiDecoder, this.token, this.exchange, config.orderWatcherConfig,
         );
-        const tokenRegistryContractAddressIfExists = _.isUndefined(config) ?
-                                                     undefined :
-                                                     config.tokenRegistryContractAddress;
-        this.tokenRegistry = new TokenRegistryWrapper(this._web3Wrapper, tokenRegistryContractAddressIfExists);
-        const etherTokenContractAddressIfExists = _.isUndefined(config) ? undefined : config.etherTokenContractAddress;
-        this.etherToken = new EtherTokenWrapper(this._web3Wrapper, this.token, etherTokenContractAddressIfExists);
     }
     /**
      * Sets a new web3 provider for 0x.js. Updating the provider will stop all
      * subscriptions so you will need to re-subscribe to all events relevant to your app after this call.
      * @param   provider    The Web3Provider you would like the 0x.js library to use from now on.
+     * @param   networkId   The id of the network your provider is connected to
      */
-    public async setProviderAsync(provider: Web3Provider) {
-        this._web3Wrapper.setProvider(provider);
-        await (this.exchange as any)._invalidateContractInstancesAsync();
+    public setProvider(provider: Web3Provider, networkId: number): void {
+        this._web3Wrapper.setProvider(provider, networkId);
+        (this.exchange as any)._invalidateContractInstances();
         (this.tokenRegistry as any)._invalidateContractInstance();
-        await (this.token as any)._invalidateContractInstancesAsync();
+        (this.token as any)._invalidateContractInstances();
         (this.proxy as any)._invalidateContractInstance();
         (this.etherToken as any)._invalidateContractInstance();
     }
@@ -298,13 +277,24 @@ export class ZeroEx {
      * Waits for a transaction to be mined and returns the transaction receipt.
      * @param   txHash            Transaction hash
      * @param   pollingIntervalMs How often (in ms) should we check if the transaction is mined.
+     * @param   timeoutMs         How long (in ms) to poll for transaction mined until aborting.
      * @return  Transaction receipt with decoded log args.
      */
     public async awaitTransactionMinedAsync(
-        txHash: string, pollingIntervalMs: number = 1000): Promise<TransactionReceiptWithDecodedLogs> {
+        txHash: string, pollingIntervalMs = 1000, timeoutMs?: number): Promise<TransactionReceiptWithDecodedLogs> {
+        let timeoutExceeded = false;
+        if (timeoutMs) {
+            setTimeout(() => timeoutExceeded = true, timeoutMs);
+        }
+
         const txReceiptPromise = new Promise(
             (resolve: (receipt: TransactionReceiptWithDecodedLogs) => void, reject) => {
             const intervalId = intervalUtils.setAsyncExcludingInterval(async () => {
+                if (timeoutExceeded) {
+                    intervalUtils.clearAsyncExcludingInterval(intervalId);
+                    return reject(ZeroExError.TransactionMiningTimeout);
+                }
+
                 const transactionReceipt = await this._web3Wrapper.getTransactionReceiptAsync(txHash);
                 if (!_.isNull(transactionReceipt)) {
                     intervalUtils.clearAsyncExcludingInterval(intervalId);
@@ -320,6 +310,7 @@ export class ZeroEx {
                 }
             }, pollingIntervalMs);
         });
+
         return txReceiptPromise;
     }
     /*

packages/0x.js/src/artifacts.ts

@@ -1,11 +1,13 @@
-import {Artifact} from './types';
-import * as TokenArtifact from './artifacts/Token.json';
-import * as ExchangeArtifact from './artifacts/Exchange.json';
 import * as EtherTokenArtifact from './artifacts/EtherToken.json';
+import * as ExchangeArtifact from './artifacts/Exchange.json';
+import * as TokenArtifact from './artifacts/Token.json';
 import * as TokenRegistryArtifact from './artifacts/TokenRegistry.json';
 import * as TokenTransferProxyArtifact from './artifacts/TokenTransferProxy.json';
+import * as ZRXArtifact from './artifacts/ZRX.json';
+import {Artifact} from './types';
 
 export const artifacts = {
+    ZRXArtifact: ZRXArtifact as any as Artifact,
     TokenArtifact: TokenArtifact as any as Artifact,
     ExchangeArtifact: ExchangeArtifact as any as Artifact,
     EtherTokenArtifact: EtherTokenArtifact as any as Artifact,

packages/0x.js/src/artifacts/EtherToken.json

@@ -0,0 +1,250 @@
+{
+  "contract_name": "EtherToken",
+  "abi": [
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "name",
+      "outputs": [
+        {
+          "name": "",
+          "type": "string"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "_spender",
+          "type": "address"
+        },
+        {
+          "name": "_value",
+          "type": "uint256"
+        }
+      ],
+      "name": "approve",
+      "outputs": [
+        {
+          "name": "",
+          "type": "bool"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "totalSupply",
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint256"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "_from",
+          "type": "address"
+        },
+        {
+          "name": "_to",
+          "type": "address"
+        },
+        {
+          "name": "_value",
+          "type": "uint256"
+        }
+      ],
+      "name": "transferFrom",
+      "outputs": [
+        {
+          "name": "",
+          "type": "bool"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "amount",
+          "type": "uint256"
+        }
+      ],
+      "name": "withdraw",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "decimals",
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint8"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "_owner",
+          "type": "address"
+        }
+      ],
+      "name": "balanceOf",
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint256"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "symbol",
+      "outputs": [
+        {
+          "name": "",
+          "type": "string"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "_to",
+          "type": "address"
+        },
+        {
+          "name": "_value",
+          "type": "uint256"
+        }
+      ],
+      "name": "transfer",
+      "outputs": [
+        {
+          "name": "",
+          "type": "bool"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [],
+      "name": "deposit",
+      "outputs": [],
+      "payable": true,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "_owner",
+          "type": "address"
+        },
+        {
+          "name": "_spender",
+          "type": "address"
+        }
+      ],
+      "name": "allowance",
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint256"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "payable": true,
+      "type": "fallback"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "_from",
+          "type": "address"
+        },
+        {
+          "indexed": true,
+          "name": "_to",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "_value",
+          "type": "uint256"
+        }
+      ],
+      "name": "Transfer",
+      "type": "event"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "_owner",
+          "type": "address"
+        },
+        {
+          "indexed": true,
+          "name": "_spender",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "_value",
+          "type": "uint256"
+        }
+      ],
+      "name": "Approval",
+      "type": "event"
+    }
+  ],
+  "networks": {
+    "1": {
+      "address": "0x2956356cd2a2bf3202f771f50d3d14a367b48070"
+    },
+    "3": {
+      "address": "0xc00fd9820cd2898cc4c054b7bf142de637ad129a"
+    },
+    "42": {
+      "address": "0x05d090b51c40b020eab3bfcb6a2dff130df22e9c"
+    },
+    "50": {
+      "address": "0x48bacb9266a570d521063ef5dd96e61686dbe788"
+    }
+  }
+}

packages/0x.js/src/artifacts/Exchange.json

@@ -0,0 +1,607 @@
+{
+  "contract_name": "Exchange",
+  "abi": [
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "numerator",
+          "type": "uint256"
+        },
+        {
+          "name": "denominator",
+          "type": "uint256"
+        },
+        {
+          "name": "target",
+          "type": "uint256"
+        }
+      ],
+      "name": "isRoundingError",
+      "outputs": [
+        {
+          "name": "",
+          "type": "bool"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "",
+          "type": "bytes32"
+        }
+      ],
+      "name": "filled",
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint256"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "",
+          "type": "bytes32"
+        }
+      ],
+      "name": "cancelled",
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint256"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "orderAddresses",
+          "type": "address[5][]"
+        },
+        {
+          "name": "orderValues",
+          "type": "uint256[6][]"
+        },
+        {
+          "name": "fillTakerTokenAmount",
+          "type": "uint256"
+        },
+        {
+          "name": "shouldThrowOnInsufficientBalanceOrAllowance",
+          "type": "bool"
+        },
+        {
+          "name": "v",
+          "type": "uint8[]"
+        },
+        {
+          "name": "r",
+          "type": "bytes32[]"
+        },
+        {
+          "name": "s",
+          "type": "bytes32[]"
+        }
+      ],
+      "name": "fillOrdersUpTo",
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint256"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "orderAddresses",
+          "type": "address[5]"
+        },
+        {
+          "name": "orderValues",
+          "type": "uint256[6]"
+        },
+        {
+          "name": "cancelTakerTokenAmount",
+          "type": "uint256"
+        }
+      ],
+      "name": "cancelOrder",
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint256"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "ZRX_TOKEN_CONTRACT",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "orderAddresses",
+          "type": "address[5][]"
+        },
+        {
+          "name": "orderValues",
+          "type": "uint256[6][]"
+        },
+        {
+          "name": "fillTakerTokenAmounts",
+          "type": "uint256[]"
+        },
+        {
+          "name": "v",
+          "type": "uint8[]"
+        },
+        {
+          "name": "r",
+          "type": "bytes32[]"
+        },
+        {
+          "name": "s",
+          "type": "bytes32[]"
+        }
+      ],
+      "name": "batchFillOrKillOrders",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "orderAddresses",
+          "type": "address[5]"
+        },
+        {
+          "name": "orderValues",
+          "type": "uint256[6]"
+        },
+        {
+          "name": "fillTakerTokenAmount",
+          "type": "uint256"
+        },
+        {
+          "name": "v",
+          "type": "uint8"
+        },
+        {
+          "name": "r",
+          "type": "bytes32"
+        },
+        {
+          "name": "s",
+          "type": "bytes32"
+        }
+      ],
+      "name": "fillOrKillOrder",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "orderHash",
+          "type": "bytes32"
+        }
+      ],
+      "name": "getUnavailableTakerTokenAmount",
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint256"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "signer",
+          "type": "address"
+        },
+        {
+          "name": "hash",
+          "type": "bytes32"
+        },
+        {
+          "name": "v",
+          "type": "uint8"
+        },
+        {
+          "name": "r",
+          "type": "bytes32"
+        },
+        {
+          "name": "s",
+          "type": "bytes32"
+        }
+      ],
+      "name": "isValidSignature",
+      "outputs": [
+        {
+          "name": "",
+          "type": "bool"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "numerator",
+          "type": "uint256"
+        },
+        {
+          "name": "denominator",
+          "type": "uint256"
+        },
+        {
+          "name": "target",
+          "type": "uint256"
+        }
+      ],
+      "name": "getPartialAmount",
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint256"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "TOKEN_TRANSFER_PROXY_CONTRACT",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "orderAddresses",
+          "type": "address[5][]"
+        },
+        {
+          "name": "orderValues",
+          "type": "uint256[6][]"
+        },
+        {
+          "name": "fillTakerTokenAmounts",
+          "type": "uint256[]"
+        },
+        {
+          "name": "shouldThrowOnInsufficientBalanceOrAllowance",
+          "type": "bool"
+        },
+        {
+          "name": "v",
+          "type": "uint8[]"
+        },
+        {
+          "name": "r",
+          "type": "bytes32[]"
+        },
+        {
+          "name": "s",
+          "type": "bytes32[]"
+        }
+      ],
+      "name": "batchFillOrders",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "orderAddresses",
+          "type": "address[5][]"
+        },
+        {
+          "name": "orderValues",
+          "type": "uint256[6][]"
+        },
+        {
+          "name": "cancelTakerTokenAmounts",
+          "type": "uint256[]"
+        }
+      ],
+      "name": "batchCancelOrders",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "orderAddresses",
+          "type": "address[5]"
+        },
+        {
+          "name": "orderValues",
+          "type": "uint256[6]"
+        },
+        {
+          "name": "fillTakerTokenAmount",
+          "type": "uint256"
+        },
+        {
+          "name": "shouldThrowOnInsufficientBalanceOrAllowance",
+          "type": "bool"
+        },
+        {
+          "name": "v",
+          "type": "uint8"
+        },
+        {
+          "name": "r",
+          "type": "bytes32"
+        },
+        {
+          "name": "s",
+          "type": "bytes32"
+        }
+      ],
+      "name": "fillOrder",
+      "outputs": [
+        {
+          "name": "filledTakerTokenAmount",
+          "type": "uint256"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "orderAddresses",
+          "type": "address[5]"
+        },
+        {
+          "name": "orderValues",
+          "type": "uint256[6]"
+        }
+      ],
+      "name": "getOrderHash",
+      "outputs": [
+        {
+          "name": "",
+          "type": "bytes32"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "EXTERNAL_QUERY_GAS_LIMIT",
+      "outputs": [
+        {
+          "name": "",
+          "type": "uint16"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "VERSION",
+      "outputs": [
+        {
+          "name": "",
+          "type": "string"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "inputs": [
+        {
+          "name": "_zrxToken",
+          "type": "address"
+        },
+        {
+          "name": "_tokenTransferProxy",
+          "type": "address"
+        }
+      ],
+      "payable": false,
+      "type": "constructor"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "maker",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "taker",
+          "type": "address"
+        },
+        {
+          "indexed": true,
+          "name": "feeRecipient",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "makerToken",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "takerToken",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "filledMakerTokenAmount",
+          "type": "uint256"
+        },
+        {
+          "indexed": false,
+          "name": "filledTakerTokenAmount",
+          "type": "uint256"
+        },
+        {
+          "indexed": false,
+          "name": "paidMakerFee",
+          "type": "uint256"
+        },
+        {
+          "indexed": false,
+          "name": "paidTakerFee",
+          "type": "uint256"
+        },
+        {
+          "indexed": true,
+          "name": "tokens",
+          "type": "bytes32"
+        },
+        {
+          "indexed": false,
+          "name": "orderHash",
+          "type": "bytes32"
+        }
+      ],
+      "name": "LogFill",
+      "type": "event"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "maker",
+          "type": "address"
+        },
+        {
+          "indexed": true,
+          "name": "feeRecipient",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "makerToken",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "takerToken",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "cancelledMakerTokenAmount",
+          "type": "uint256"
+        },
+        {
+          "indexed": false,
+          "name": "cancelledTakerTokenAmount",
+          "type": "uint256"
+        },
+        {
+          "indexed": true,
+          "name": "tokens",
+          "type": "bytes32"
+        },
+        {
+          "indexed": false,
+          "name": "orderHash",
+          "type": "bytes32"
+        }
+      ],
+      "name": "LogCancel",
+      "type": "event"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "errorId",
+          "type": "uint8"
+        },
+        {
+          "indexed": true,
+          "name": "orderHash",
+          "type": "bytes32"
+        }
+      ],
+      "name": "LogError",
+      "type": "event"
+    }
+  ],
+  "networks": {
+    "1": {
+      "address": "0x12459c951127e0c374ff9105dda097662a027093"
+    },
+    "3": {
+      "address": "0x479cc461fecd078f766ecc58533d6f69580cf3ac"
+    },
+    "42": {
+      "address": "0x90fe2af704b34e0224bf2299c838e04d4dcf1364"
+    },
+    "50": {
+      "address": "0xb69e673309512a9d726f87304c6984054f87a93b"
+    }
+  }
+}

packages/0x.js/src/artifacts/Token.json

@@ -168,9 +168,5 @@
       "name": "Approval",
       "type": "event"
     }
-  ],
-  "unlinked_binary": "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",
-  "networks": {},
-  "schema_version": "0.0.5",
-  "updated_at": 1503317882695
-}
+  ]
+}

packages/0x.js/src/artifacts/TokenRegistry.json

@@ -0,0 +1,544 @@
+{
+  "contract_name": "TokenRegistry",
+  "abi": [
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "_token",
+          "type": "address"
+        },
+        {
+          "name": "_index",
+          "type": "uint256"
+        }
+      ],
+      "name": "removeToken",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "_name",
+          "type": "string"
+        }
+      ],
+      "name": "getTokenAddressByName",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "_symbol",
+          "type": "string"
+        }
+      ],
+      "name": "getTokenAddressBySymbol",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "_token",
+          "type": "address"
+        },
+        {
+          "name": "_swarmHash",
+          "type": "bytes"
+        }
+      ],
+      "name": "setTokenSwarmHash",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "_token",
+          "type": "address"
+        }
+      ],
+      "name": "getTokenMetaData",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address"
+        },
+        {
+          "name": "",
+          "type": "string"
+        },
+        {
+          "name": "",
+          "type": "string"
+        },
+        {
+          "name": "",
+          "type": "uint8"
+        },
+        {
+          "name": "",
+          "type": "bytes"
+        },
+        {
+          "name": "",
+          "type": "bytes"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "owner",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "_token",
+          "type": "address"
+        },
+        {
+          "name": "_name",
+          "type": "string"
+        },
+        {
+          "name": "_symbol",
+          "type": "string"
+        },
+        {
+          "name": "_decimals",
+          "type": "uint8"
+        },
+        {
+          "name": "_ipfsHash",
+          "type": "bytes"
+        },
+        {
+          "name": "_swarmHash",
+          "type": "bytes"
+        }
+      ],
+      "name": "addToken",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "_token",
+          "type": "address"
+        },
+        {
+          "name": "_name",
+          "type": "string"
+        }
+      ],
+      "name": "setTokenName",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "",
+          "type": "address"
+        }
+      ],
+      "name": "tokens",
+      "outputs": [
+        {
+          "name": "token",
+          "type": "address"
+        },
+        {
+          "name": "name",
+          "type": "string"
+        },
+        {
+          "name": "symbol",
+          "type": "string"
+        },
+        {
+          "name": "decimals",
+          "type": "uint8"
+        },
+        {
+          "name": "ipfsHash",
+          "type": "bytes"
+        },
+        {
+          "name": "swarmHash",
+          "type": "bytes"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "",
+          "type": "uint256"
+        }
+      ],
+      "name": "tokenAddresses",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "_name",
+          "type": "string"
+        }
+      ],
+      "name": "getTokenByName",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address"
+        },
+        {
+          "name": "",
+          "type": "string"
+        },
+        {
+          "name": "",
+          "type": "string"
+        },
+        {
+          "name": "",
+          "type": "uint8"
+        },
+        {
+          "name": "",
+          "type": "bytes"
+        },
+        {
+          "name": "",
+          "type": "bytes"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "getTokenAddresses",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address[]"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "_token",
+          "type": "address"
+        },
+        {
+          "name": "_ipfsHash",
+          "type": "bytes"
+        }
+      ],
+      "name": "setTokenIpfsHash",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "_symbol",
+          "type": "string"
+        }
+      ],
+      "name": "getTokenBySymbol",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address"
+        },
+        {
+          "name": "",
+          "type": "string"
+        },
+        {
+          "name": "",
+          "type": "string"
+        },
+        {
+          "name": "",
+          "type": "uint8"
+        },
+        {
+          "name": "",
+          "type": "bytes"
+        },
+        {
+          "name": "",
+          "type": "bytes"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "_token",
+          "type": "address"
+        },
+        {
+          "name": "_symbol",
+          "type": "string"
+        }
+      ],
+      "name": "setTokenSymbol",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "newOwner",
+          "type": "address"
+        }
+      ],
+      "name": "transferOwnership",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "token",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "name",
+          "type": "string"
+        },
+        {
+          "indexed": false,
+          "name": "symbol",
+          "type": "string"
+        },
+        {
+          "indexed": false,
+          "name": "decimals",
+          "type": "uint8"
+        },
+        {
+          "indexed": false,
+          "name": "ipfsHash",
+          "type": "bytes"
+        },
+        {
+          "indexed": false,
+          "name": "swarmHash",
+          "type": "bytes"
+        }
+      ],
+      "name": "LogAddToken",
+      "type": "event"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "token",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "name",
+          "type": "string"
+        },
+        {
+          "indexed": false,
+          "name": "symbol",
+          "type": "string"
+        },
+        {
+          "indexed": false,
+          "name": "decimals",
+          "type": "uint8"
+        },
+        {
+          "indexed": false,
+          "name": "ipfsHash",
+          "type": "bytes"
+        },
+        {
+          "indexed": false,
+          "name": "swarmHash",
+          "type": "bytes"
+        }
+      ],
+      "name": "LogRemoveToken",
+      "type": "event"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "token",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "oldName",
+          "type": "string"
+        },
+        {
+          "indexed": false,
+          "name": "newName",
+          "type": "string"
+        }
+      ],
+      "name": "LogTokenNameChange",
+      "type": "event"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "token",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "oldSymbol",
+          "type": "string"
+        },
+        {
+          "indexed": false,
+          "name": "newSymbol",
+          "type": "string"
+        }
+      ],
+      "name": "LogTokenSymbolChange",
+      "type": "event"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "token",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "oldIpfsHash",
+          "type": "bytes"
+        },
+        {
+          "indexed": false,
+          "name": "newIpfsHash",
+          "type": "bytes"
+        }
+      ],
+      "name": "LogTokenIpfsHashChange",
+      "type": "event"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "token",
+          "type": "address"
+        },
+        {
+          "indexed": false,
+          "name": "oldSwarmHash",
+          "type": "bytes"
+        },
+        {
+          "indexed": false,
+          "name": "newSwarmHash",
+          "type": "bytes"
+        }
+      ],
+      "name": "LogTokenSwarmHashChange",
+      "type": "event"
+    }
+  ],
+  "networks": {
+    "1": {
+      "address": "0x926a74c5c36adf004c87399e65f75628b0f98d2c"
+    },
+    "3": {
+      "address": "0x6b1a50f0bb5a7995444bd3877b22dc89c62843ed"
+    },
+    "42": {
+      "address": "0xf18e504561f4347bea557f3d4558f559dddbae7f"
+    },
+    "50": {
+      "address": "0x0b1ba0af832d7c05fd64161e0db78e85978e8082"
+    }
+  }
+}

packages/0x.js/src/artifacts/TokenTransferProxy.json

@@ -0,0 +1,184 @@
+{
+  "contract_name": "TokenTransferProxy",
+  "abi": [
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "token",
+          "type": "address"
+        },
+        {
+          "name": "from",
+          "type": "address"
+        },
+        {
+          "name": "to",
+          "type": "address"
+        },
+        {
+          "name": "value",
+          "type": "uint256"
+        }
+      ],
+      "name": "transferFrom",
+      "outputs": [
+        {
+          "name": "",
+          "type": "bool"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "target",
+          "type": "address"
+        }
+      ],
+      "name": "addAuthorizedAddress",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "",
+          "type": "uint256"
+        }
+      ],
+      "name": "authorities",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "target",
+          "type": "address"
+        }
+      ],
+      "name": "removeAuthorizedAddress",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "owner",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [
+        {
+          "name": "",
+          "type": "address"
+        }
+      ],
+      "name": "authorized",
+      "outputs": [
+        {
+          "name": "",
+          "type": "bool"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": true,
+      "inputs": [],
+      "name": "getAuthorizedAddresses",
+      "outputs": [
+        {
+          "name": "",
+          "type": "address[]"
+        }
+      ],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "constant": false,
+      "inputs": [
+        {
+          "name": "newOwner",
+          "type": "address"
+        }
+      ],
+      "name": "transferOwnership",
+      "outputs": [],
+      "payable": false,
+      "type": "function"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "target",
+          "type": "address"
+        },
+        {
+          "indexed": true,
+          "name": "caller",
+          "type": "address"
+        }
+      ],
+      "name": "LogAuthorizedAddressAdded",
+      "type": "event"
+    },
+    {
+      "anonymous": false,
+      "inputs": [
+        {
+          "indexed": true,
+          "name": "target",
+          "type": "address"
+        },
+        {
+          "indexed": true,
+          "name": "caller",
+          "type": "address"
+        }
+      ],
+      "name": "LogAuthorizedAddressRemoved",
+      "type": "event"
+    }
+  ],
+  "networks": {
+      "1": {
+        "address": "0x8da0d80f5007ef1e431dd2127178d224e32c2ef4"
+      },
+      "3": {
+        "address": "0x4e9aad8184de8833365fea970cd9149372fdf1e6"
+      },
+      "42": {
+        "address": "0x087eed4bc1ee3de49befbd66c662b434b15d49d4"
+      },
+      "50": {
+        "address": "0x871dd7c2b4b25e1aa18728e9d5f2af4c4e431f5c"
+      }
+  }
+}

packages/0x.js/src/artifacts/ZRX.json

@@ -0,0 +1,17 @@
+{
+  "contract_name": "ZRX",
+  "networks": {
+    "1": {
+      "address": "0xe41d2489571d322189246dafa5ebde1f4699f498"
+    },
+    "3": {
+      "address": "0xa8e9fa8f91e5ae138c74648c9c304f1c75003a8d"
+    },
+    "42": {
+      "address": "0x6ff6c0ff1d68b964901f986d4c9fa3ac68346570"
+    },
+    "50": {
+      "address": "0x25b8fe1de9daf8ba351890744ff28cf7dfa8f5e3"
+    }
+  }
+}

packages/0x.js/src/bignumber_config.ts

@@ -1,4 +1,4 @@
-import * as BigNumber from 'bignumber.js';
+import BigNumber from 'bignumber.js';
 
 export const bigNumberConfigs = {
     configure() {

packages/0x.js/src/contract.ts

@@ -1,9 +1,14 @@
-import * as Web3 from 'web3';
-import * as _ from 'lodash';
+import {schemas, SchemaValidator} from '@0xproject/json-schemas';
 import promisify = require('es6-promisify');
-import {SchemaValidator, schemas} from '0x-json-schemas';
+import * as _ from 'lodash';
+import * as Web3 from 'web3';
+
 import {AbiType} from './types';
 
+// HACK: Gas estimates on testrpc don't take into account gas refunds.
+// Our calls can trigger max 8 gas refunds for SSTORE per transaction for 15k gas each which gives 120k.
+const GAS_MARGIN = 120000;
+
 export class Contract implements Web3.ContractInstance {
     public address: string;
     public abi: Web3.ContractAbi;
@@ -33,9 +38,10 @@ export class Contract implements Web3.ContractInstance {
             } else {
                 const cbStyleFunction = this.contract[functionAbi.name];
                 const cbStyleEstimateGasFunction = this.contract[functionAbi.name].estimateGas;
+                const estimateGasAsync = promisify(cbStyleEstimateGasFunction, this.contract);
                 this[functionAbi.name] = {
-                    estimateGasAsync: promisify(cbStyleEstimateGasFunction, this.contract),
-                    sendTransactionAsync: this.promisifyWithDefaultParams(cbStyleFunction),
+                    estimateGasAsync,
+                    sendTransactionAsync: this.promisifyWithDefaultParams(cbStyleFunction, estimateGasAsync),
                 };
             }
         });
@@ -46,28 +52,40 @@ export class Contract implements Web3.ContractInstance {
             this[eventAbi.name] = this.contract[eventAbi.name];
         });
     }
-    private promisifyWithDefaultParams(fn: (...args: any[]) => void): (...args: any[]) => Promise<any> {
-        const promisifiedWithDefaultParams = (...args: any[]) => {
-            const promise = new Promise((resolve, reject) => {
+    private promisifyWithDefaultParams(
+        web3CbStyleFunction: (...args: any[]) => void,
+        estimateGasAsync: (...args: any[]) => Promise<number>,
+    ): (...args: any[]) => Promise<any> {
+        const promisifiedWithDefaultParams = async (...args: any[]) => {
+            const promise = new Promise(async (resolve, reject) => {
                 const lastArg = args[args.length - 1];
                 let txData: Partial<Web3.TxData> = {};
-                if (this.isTxData(lastArg)) {
+                if (!_.isUndefined(lastArg) && this.isTxData(lastArg)) {
                     txData = args.pop();
                 }
+                // Gas amount sourced with the following priorities:
+                // 1. Optional param passed in to public method call
+                // 2. Global config passed in at library instantiation
+                // 3. Gas estimate calculation + safety margin
+                const removeUndefinedProperties = _.pickBy;
                 txData = {
-                    ...this.defaults,
-                    ...txData,
+                    ...removeUndefinedProperties(this.defaults),
+                    ...removeUndefinedProperties(txData),
                 };
-                const callback = (err: Error, data: any) => {
-                    if (_.isNull(err)) {
-                        resolve(data);
-                    } else {
+                if (_.isUndefined(txData.gas)) {
+                    try {
+                        const estimatedGas = await estimateGasAsync.apply(this.contract, [...args, txData]);
+                        const gas = estimatedGas + GAS_MARGIN;
+                        txData.gas = gas;
+                    } catch (err) {
                         reject(err);
+                        return;
                     }
-                };
+                }
+                const callback = (err: Error, data: any) => _.isNull(err) ? resolve(data) : reject(err);
                 args.push(txData);
                 args.push(callback);
-                fn.apply(this.contract, args);
+                web3CbStyleFunction.apply(this.contract, args);
             });
             return promise;
         };

packages/0x.js/src/contract_wrappers/contract_wrapper.ts

@@ -0,0 +1,165 @@
+import {Block, BlockAndLogStreamer} from 'ethereumjs-blockstream';
+import * as _ from 'lodash';
+import * as Web3 from 'web3';
+
+import {
+    Artifact,
+    BlockParamLiteral,
+    ContractEventArgs,
+    ContractEvents,
+    EventCallback,
+    IndexedFilterValues,
+    InternalZeroExError,
+    LogWithDecodedArgs,
+    RawLog,
+    SubscriptionOpts,
+    ZeroExError,
+} from '../types';
+import {AbiDecoder} from '../utils/abi_decoder';
+import {constants} from '../utils/constants';
+import {filterUtils} from '../utils/filter_utils';
+import {intervalUtils} from '../utils/interval_utils';
+import {Web3Wrapper} from '../web3_wrapper';
+
+export class ContractWrapper {
+    protected _web3Wrapper: Web3Wrapper;
+    private _abiDecoder?: AbiDecoder;
+    private _blockAndLogStreamer: BlockAndLogStreamer|undefined;
+    private _blockAndLogStreamInterval: NodeJS.Timer;
+    private _filters: {[filterToken: string]: Web3.FilterObject};
+    private _filterCallbacks: {[filterToken: string]: EventCallback<ContractEventArgs>};
+    private _onLogAddedSubscriptionToken: string|undefined;
+    private _onLogRemovedSubscriptionToken: string|undefined;
+    constructor(web3Wrapper: Web3Wrapper, abiDecoder?: AbiDecoder) {
+        this._web3Wrapper = web3Wrapper;
+        this._abiDecoder = abiDecoder;
+        this._filters = {};
+        this._filterCallbacks = {};
+        this._blockAndLogStreamer = undefined;
+        this._onLogAddedSubscriptionToken = undefined;
+        this._onLogRemovedSubscriptionToken = undefined;
+    }
+    /**
+     * Cancels all existing subscriptions
+     */
+    public unsubscribeAll(): void {
+        const filterTokens = _.keys(this._filterCallbacks);
+        _.each(filterTokens, filterToken => {
+            this._unsubscribe(filterToken);
+        });
+    }
+    protected _unsubscribe(filterToken: string, err?: Error): void {
+        if (_.isUndefined(this._filters[filterToken])) {
+            throw new Error(ZeroExError.SubscriptionNotFound);
+        }
+        if (!_.isUndefined(err)) {
+            const callback = this._filterCallbacks[filterToken];
+            callback(err, undefined);
+        }
+        delete this._filters[filterToken];
+        delete this._filterCallbacks[filterToken];
+        if (_.isEmpty(this._filters)) {
+            this._stopBlockAndLogStream();
+        }
+    }
+    protected _subscribe<ArgsType extends ContractEventArgs>(
+        address: string, eventName: ContractEvents, indexFilterValues: IndexedFilterValues, abi: Web3.ContractAbi,
+        callback: EventCallback<ArgsType>): string {
+        const filter = filterUtils.getFilter(address, eventName, indexFilterValues, abi);
+        if (_.isUndefined(this._blockAndLogStreamer)) {
+            this._startBlockAndLogStream();
+        }
+        const filterToken = filterUtils.generateUUID();
+        this._filters[filterToken] = filter;
+        this._filterCallbacks[filterToken] = callback;
+        return filterToken;
+    }
+    protected async _getLogsAsync<ArgsType extends ContractEventArgs>(
+        address: string, eventName: ContractEvents, subscriptionOpts: SubscriptionOpts,
+        indexFilterValues: IndexedFilterValues, abi: Web3.ContractAbi): Promise<Array<LogWithDecodedArgs<ArgsType>>> {
+        const filter = filterUtils.getFilter(address, eventName, indexFilterValues, abi, subscriptionOpts);
+        const logs = await this._web3Wrapper.getLogsAsync(filter);
+        const logsWithDecodedArguments = _.map(logs, this._tryToDecodeLogOrNoop.bind(this));
+        return logsWithDecodedArguments;
+    }
+    protected _tryToDecodeLogOrNoop<ArgsType extends ContractEventArgs>(
+        log: Web3.LogEntry): LogWithDecodedArgs<ArgsType>|RawLog {
+        if (_.isUndefined(this._abiDecoder)) {
+            throw new Error(InternalZeroExError.NoAbiDecoder);
+        }
+        const logWithDecodedArgs = this._abiDecoder.tryToDecodeLogOrNoop(log);
+        return logWithDecodedArgs;
+    }
+    protected async _instantiateContractIfExistsAsync<ContractType extends Web3.ContractInstance>(
+        artifact: Artifact, addressIfExists?: string): Promise<ContractType> {
+        const contractInstance =
+            await this._web3Wrapper.getContractInstanceFromArtifactAsync<ContractType>(artifact, addressIfExists);
+        return contractInstance;
+    }
+    protected _getContractAddress(artifact: Artifact, addressIfExists?: string): string {
+        if (_.isUndefined(addressIfExists)) {
+            const networkId = this._web3Wrapper.getNetworkId();
+            const contractAddress = artifact.networks[networkId].address;
+            if (_.isUndefined(contractAddress)) {
+                throw new Error(ZeroExError.ExchangeContractDoesNotExist);
+            }
+            return contractAddress;
+        } else {
+            return addressIfExists;
+        }
+    }
+    private _onLogStateChanged<ArgsType extends ContractEventArgs>(isRemoved: boolean, log: Web3.LogEntry): void {
+        _.forEach(this._filters, (filter: Web3.FilterObject, filterToken: string) => {
+            if (filterUtils.matchesFilter(log, filter)) {
+                const decodedLog = this._tryToDecodeLogOrNoop(log) as LogWithDecodedArgs<ArgsType>;
+                const logEvent = {
+                    log: decodedLog,
+                    isRemoved,
+                };
+                this._filterCallbacks[filterToken](null, logEvent);
+            }
+        });
+    }
+    private _startBlockAndLogStream(): void {
+        this._blockAndLogStreamer = new BlockAndLogStreamer(
+            this._web3Wrapper.getBlockAsync.bind(this._web3Wrapper),
+            this._web3Wrapper.getLogsAsync.bind(this._web3Wrapper),
+        );
+        const catchAllLogFilter = {};
+        this._blockAndLogStreamer.addLogFilter(catchAllLogFilter);
+        this._blockAndLogStreamInterval = intervalUtils.setAsyncExcludingInterval(
+            this._reconcileBlockAsync.bind(this), constants.DEFAULT_BLOCK_POLLING_INTERVAL,
+        );
+        let isRemoved = false;
+        this._onLogAddedSubscriptionToken = this._blockAndLogStreamer.subscribeToOnLogAdded(
+            this._onLogStateChanged.bind(this, isRemoved),
+        );
+        isRemoved = true;
+        this._onLogRemovedSubscriptionToken = this._blockAndLogStreamer.subscribeToOnLogRemoved(
+            this._onLogStateChanged.bind(this, isRemoved),
+        );
+    }
+    private _stopBlockAndLogStream(): void {
+        (this._blockAndLogStreamer as BlockAndLogStreamer).unsubscribeFromOnLogAdded(
+            this._onLogAddedSubscriptionToken as string);
+        (this._blockAndLogStreamer as BlockAndLogStreamer).unsubscribeFromOnLogRemoved(
+            this._onLogRemovedSubscriptionToken as string);
+        intervalUtils.clearAsyncExcludingInterval(this._blockAndLogStreamInterval);
+        delete this._blockAndLogStreamer;
+    }
+    private async _reconcileBlockAsync(): Promise<void> {
+        try {
+            const latestBlock = await this._web3Wrapper.getBlockAsync(BlockParamLiteral.Latest);
+            // We need to coerce to Block type cause Web3.Block includes types for mempool blocks
+            if (!_.isUndefined(this._blockAndLogStreamer)) {
+                // If we clear the interval while fetching the block - this._blockAndLogStreamer will be undefined
+                await this._blockAndLogStreamer.reconcileNewBlock(latestBlock as any as Block);
+            }
+        } catch (err) {
+            const filterTokens = _.keys(this._filterCallbacks);
+            _.each(filterTokens, filterToken => {
+                this._unsubscribe(filterToken, err);
+            });
+        }
+    }
+}

packages/0x.js/src/contract_wrappers/ether_token_wrapper.ts

@@ -1,10 +1,13 @@
+import BigNumber from 'bignumber.js';
 import * as _ from 'lodash';
+
+import {artifacts} from '../artifacts';
+import {EtherTokenContract, TransactionOpts, ZeroExError} from '../types';
+import {assert} from '../utils/assert';
 import {Web3Wrapper} from '../web3_wrapper';
+
 import {ContractWrapper} from './contract_wrapper';
 import {TokenWrapper} from './token_wrapper';
-import {EtherTokenContract, ZeroExError} from '../types';
-import {assert} from '../utils/assert';
-import {artifacts} from '../artifacts';
 
 /**
  * This class includes all the functionality related to interacting with a wrapped Ether ERC20 token contract.
@@ -24,11 +27,14 @@ export class EtherTokenWrapper extends ContractWrapper {
      * to the depositor address. These wrapped ETH tokens can be used in 0x trades and are redeemable for 1-to-1
      * for ETH.
      * @param   amountInWei      Amount of ETH in Wei the caller wishes to deposit.
-     * @param   depositor   The hex encoded user Ethereum address that would like to make the deposit.
+     * @param   depositor        The hex encoded user Ethereum address that would like to make the deposit.
+     * @param   txOpts           Transaction parameters.
      * @return Transaction hash.
      */
-    public async depositAsync(amountInWei: BigNumber.BigNumber, depositor: string): Promise<string> {
-        assert.isBigNumber('amountInWei', amountInWei);
+    public async depositAsync(
+        amountInWei: BigNumber, depositor: string, txOpts: TransactionOpts = {},
+    ): Promise<string> {
+        assert.isValidBaseUnitAmount('amountInWei', amountInWei);
         await assert.isSenderAddressAsync('depositor', depositor, this._web3Wrapper);
 
         const ethBalanceInWei = await this._web3Wrapper.getBalanceInWeiAsync(depositor);
@@ -38,6 +44,8 @@ export class EtherTokenWrapper extends ContractWrapper {
         const txHash = await wethContract.deposit.sendTransactionAsync({
             from: depositor,
             value: amountInWei,
+            gas: txOpts.gasLimit,
+            gasPrice: txOpts.gasPrice,
         });
         return txHash;
     }
@@ -46,19 +54,24 @@ export class EtherTokenWrapper extends ContractWrapper {
      * equivalent number of wrapped ETH tokens.
      * @param   amountInWei  Amount of ETH in Wei the caller wishes to withdraw.
      * @param   withdrawer   The hex encoded user Ethereum address that would like to make the withdrawl.
+     * @param   txOpts       Transaction parameters.
      * @return Transaction hash.
      */
-    public async withdrawAsync(amountInWei: BigNumber.BigNumber, withdrawer: string): Promise<string> {
-        assert.isBigNumber('amountInWei', amountInWei);
+    public async withdrawAsync(
+        amountInWei: BigNumber, withdrawer: string, txOpts: TransactionOpts = {},
+    ): Promise<string> {
+        assert.isValidBaseUnitAmount('amountInWei', amountInWei);
         await assert.isSenderAddressAsync('withdrawer', withdrawer, this._web3Wrapper);
 
-        const wethContractAddress = await this.getContractAddressAsync();
+        const wethContractAddress = this.getContractAddress();
         const WETHBalanceInBaseUnits = await this._tokenWrapper.getBalanceAsync(wethContractAddress, withdrawer);
         assert.assert(WETHBalanceInBaseUnits.gte(amountInWei), ZeroExError.InsufficientWEthBalanceForWithdrawal);
 
         const wethContract = await this._getEtherTokenContractAsync();
         const txHash = await wethContract.withdraw.sendTransactionAsync(amountInWei, {
             from: withdrawer,
+            gas: txOpts.gasLimit,
+            gasPrice: txOpts.gasPrice,
         });
         return txHash;
     }
@@ -66,9 +79,11 @@ export class EtherTokenWrapper extends ContractWrapper {
      * Retrieves the Wrapped Ether token contract address
      * @return  The Wrapped Ether token contract address
      */
-    public async getContractAddressAsync(): Promise<string> {
-        const wethContract = await this._getEtherTokenContractAsync();
-        return wethContract.address;
+    public getContractAddress(): string {
+        const contractAddress = this._getContractAddress(
+            artifacts.EtherTokenArtifact, this._contractAddressIfExists,
+        );
+        return contractAddress;
     }
     private _invalidateContractInstance(): void {
         delete this._etherTokenContractIfExists;
@@ -80,7 +95,7 @@ export class EtherTokenWrapper extends ContractWrapper {
         const contractInstance = await this._instantiateContractIfExistsAsync<EtherTokenContract>(
             artifacts.EtherTokenArtifact, this._contractAddressIfExists,
         );
-        this._etherTokenContractIfExists = contractInstance as EtherTokenContract;
+        this._etherTokenContractIfExists = contractInstance;
         return this._etherTokenContractIfExists;
     }
 }

packages/0x.js/src/contract_wrappers/exchange_wrapper.ts

@@ -1,60 +1,62 @@
+import {schemas} from '@0xproject/json-schemas';
+import BigNumber from 'bignumber.js';
 import * as _ from 'lodash';
-import * as BigNumber from 'bignumber.js';
-import {SchemaValidator, schemas} from '0x-json-schemas';
-import promisify = require('es6-promisify');
-import {Web3Wrapper} from '../web3_wrapper';
+import * as Web3 from 'web3';
+
+import {artifacts} from '../artifacts';
 import {
+    BlockParamLiteral,
+    DecodedLogArgs,
     ECSignature,
+    EventCallback,
     ExchangeContract,
     ExchangeContractErrCodes,
     ExchangeContractErrs,
-    ZeroExError,
-    OrderValues,
-    OrderAddresses,
-    Order,
-    OrderFillOrKillRequest,
-    SignedOrder,
-    ContractEvent,
+    ExchangeContractEventArgs,
     ExchangeEvents,
-    ContractEventEmitter,
-    SubscriptionOpts,
     IndexedFilterValues,
-    CreateContractEvent,
-    ContractEventObj,
-    OrderCancellationRequest,
-    OrderFillRequest,
+    LogCancelContractEventArgs,
     LogErrorContractEventArgs,
     LogFillContractEventArgs,
-    LogCancelContractEventArgs,
     LogWithDecodedArgs,
     MethodOpts,
-    ValidateOrderFillableOpts,
+    Order,
+    OrderAddresses,
+    OrderCancellationRequest,
+    OrderFillRequest,
     OrderTransactionOpts,
+    OrderValues,
     RawLog,
+    SignedOrder,
+    SubscriptionOpts,
+    ValidateOrderFillableOpts,
 } from '../types';
-import {assert} from '../utils/assert';
-import {utils} from '../utils/utils';
-import {eventUtils} from '../utils/event_utils';
-import {OrderValidationUtils} from '../utils/order_validation_utils';
-import {ContractWrapper} from './contract_wrapper';
-import {constants} from '../utils/constants';
-import {TokenWrapper} from './token_wrapper';
-import {decorators} from '../utils/decorators';
 import {AbiDecoder} from '../utils/abi_decoder';
-import {artifacts} from '../artifacts';
+import {assert} from '../utils/assert';
+import {decorators} from '../utils/decorators';
+import {ExchangeTransferSimulator} from '../utils/exchange_transfer_simulator';
+import {OrderValidationUtils} from '../utils/order_validation_utils';
+import {utils} from '../utils/utils';
+import {Web3Wrapper} from '../web3_wrapper';
+
+import {ContractWrapper} from './contract_wrapper';
+import {TokenWrapper} from './token_wrapper';
 
 const SHOULD_VALIDATE_BY_DEFAULT = true;
 
+interface ExchangeContractErrCodesToMsgs {
+    [exchangeContractErrCodes: number]: string;
+}
+
 /**
  * This class includes all the functionality related to calling methods and subscribing to
  * events of the 0x Exchange smart contract.
  */
 export class ExchangeWrapper extends ContractWrapper {
     private _exchangeContractIfExists?: ExchangeContract;
-    private _exchangeLogEventEmitters: ContractEventEmitter[];
     private _orderValidationUtils: OrderValidationUtils;
     private _tokenWrapper: TokenWrapper;
-    private _exchangeContractErrCodesToMsg = {
+    private _exchangeContractErrCodesToMsg: ExchangeContractErrCodesToMsgs = {
         [ExchangeContractErrCodes.ERROR_FILL_EXPIRED]: ExchangeContractErrs.OrderFillExpired,
         [ExchangeContractErrCodes.ERROR_CANCEL_EXPIRED]: ExchangeContractErrs.OrderFillExpired,
         [ExchangeContractErrCodes.ERROR_FILL_NO_VALUE]: ExchangeContractErrs.OrderRemainingFillAmountZero,
@@ -63,6 +65,7 @@ export class ExchangeWrapper extends ContractWrapper {
         [ExchangeContractErrCodes.ERROR_FILL_BALANCE_ALLOWANCE]: ExchangeContractErrs.FillBalanceAllowanceError,
     };
     private _contractAddressIfExists?: string;
+    private _zrxContractAddressIfExists?: string;
     private static _getOrderAddressesAndValues(order: Order): [OrderAddresses, OrderValues] {
         const orderAddresses: OrderAddresses = [
             order.maker,
@@ -86,7 +89,6 @@ export class ExchangeWrapper extends ContractWrapper {
         super(web3Wrapper, abiDecoder);
         this._tokenWrapper = tokenWrapper;
         this._orderValidationUtils = new OrderValidationUtils(tokenWrapper, this);
-        this._exchangeLogEventEmitters = [];
         this._contractAddressIfExists = contractAddressIfExists;
     }
     /**
@@ -96,10 +98,10 @@ export class ExchangeWrapper extends ContractWrapper {
      * @param   orderHash               The hex encoded orderHash for which you would like to retrieve the
      *                                  unavailable takerAmount.
      * @param   methodOpts              Optional arguments this method accepts.
-     * @return  The amount of the order (in taker tokens) that has either been filled or canceled.
+     * @return  The amount of the order (in taker tokens) that has either been filled or cancelled.
      */
     public async getUnavailableTakerAmountAsync(orderHash: string,
-                                                methodOpts?: MethodOpts): Promise<BigNumber.BigNumber> {
+                                                methodOpts?: MethodOpts): Promise<BigNumber> {
         assert.doesConformToSchema('orderHash', orderHash, schemas.orderHashSchema);
 
         const exchangeContract = await this._getExchangeContractAsync();
@@ -117,7 +119,7 @@ export class ExchangeWrapper extends ContractWrapper {
      * @param   methodOpts   Optional arguments this method accepts.
      * @return  The amount of the order (in taker tokens) that has already been filled.
      */
-    public async getFilledTakerAmountAsync(orderHash: string, methodOpts?: MethodOpts): Promise<BigNumber.BigNumber> {
+    public async getFilledTakerAmountAsync(orderHash: string, methodOpts?: MethodOpts): Promise<BigNumber> {
         assert.doesConformToSchema('orderHash', orderHash, schemas.orderHashSchema);
 
         const exchangeContract = await this._getExchangeContractAsync();
@@ -134,7 +136,7 @@ export class ExchangeWrapper extends ContractWrapper {
      * @param   methodOpts   Optional arguments this method accepts.
      * @return  The amount of the order (in taker tokens) that has been cancelled.
      */
-    public async getCanceledTakerAmountAsync(orderHash: string, methodOpts?: MethodOpts): Promise<BigNumber.BigNumber> {
+    public async getCancelledTakerAmountAsync(orderHash: string, methodOpts?: MethodOpts): Promise<BigNumber> {
         assert.doesConformToSchema('orderHash', orderHash, schemas.orderHashSchema);
 
         const exchangeContract = await this._getExchangeContractAsync();
@@ -164,37 +166,28 @@ export class ExchangeWrapper extends ContractWrapper {
      * @return  Transaction hash.
      */
     @decorators.contractCallErrorHandler
-    public async fillOrderAsync(signedOrder: SignedOrder, fillTakerTokenAmount: BigNumber.BigNumber,
+    public async fillOrderAsync(signedOrder: SignedOrder, fillTakerTokenAmount: BigNumber,
                                 shouldThrowOnInsufficientBalanceOrAllowance: boolean,
                                 takerAddress: string,
-                                orderTransactionOpts?: OrderTransactionOpts): Promise<string> {
+                                orderTransactionOpts: OrderTransactionOpts = {}): Promise<string> {
         assert.doesConformToSchema('signedOrder', signedOrder, schemas.signedOrderSchema);
-        assert.isBigNumber('fillTakerTokenAmount', fillTakerTokenAmount);
+        assert.isValidBaseUnitAmount('fillTakerTokenAmount', fillTakerTokenAmount);
         assert.isBoolean('shouldThrowOnInsufficientBalanceOrAllowance', shouldThrowOnInsufficientBalanceOrAllowance);
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
 
         const exchangeInstance = await this._getExchangeContractAsync();
-        const shouldValidate = _.isUndefined(orderTransactionOpts) ?
-            SHOULD_VALIDATE_BY_DEFAULT :
-            orderTransactionOpts.shouldValidate;
+        const shouldValidate = _.isUndefined(orderTransactionOpts.shouldValidate) ?
+                               SHOULD_VALIDATE_BY_DEFAULT :
+                               orderTransactionOpts.shouldValidate;
         if (shouldValidate) {
-            await this.validateFillOrderThrowIfInvalidAsync(signedOrder, fillTakerTokenAmount, takerAddress);
+            const zrxTokenAddress = this.getZRXTokenAddress();
+            const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+            await this._orderValidationUtils.validateFillOrderThrowIfInvalidAsync(
+                exchangeTradeEmulator, signedOrder, fillTakerTokenAmount, takerAddress, zrxTokenAddress);
         }
 
         const [orderAddresses, orderValues] = ExchangeWrapper._getOrderAddressesAndValues(signedOrder);
 
-        const gas = await exchangeInstance.fillOrder.estimateGasAsync(
-            orderAddresses,
-            orderValues,
-            fillTakerTokenAmount,
-            shouldThrowOnInsufficientBalanceOrAllowance,
-            signedOrder.ecSignature.v,
-            signedOrder.ecSignature.r,
-            signedOrder.ecSignature.s,
-            {
-                from: takerAddress,
-            },
-        );
         const txHash: string = await exchangeInstance.fillOrder.sendTransactionAsync(
             orderAddresses,
             orderValues,
@@ -205,7 +198,8 @@ export class ExchangeWrapper extends ContractWrapper {
             signedOrder.ecSignature.s,
             {
                 from: takerAddress,
-                gas,
+                gas: orderTransactionOpts.gasLimit,
+                gasPrice: orderTransactionOpts.gasPrice,
             },
         );
         return txHash;
@@ -228,10 +222,10 @@ export class ExchangeWrapper extends ContractWrapper {
      * @return  Transaction hash.
      */
     @decorators.contractCallErrorHandler
-    public async fillOrdersUpToAsync(signedOrders: SignedOrder[], fillTakerTokenAmount: BigNumber.BigNumber,
+    public async fillOrdersUpToAsync(signedOrders: SignedOrder[], fillTakerTokenAmount: BigNumber,
                                      shouldThrowOnInsufficientBalanceOrAllowance: boolean,
                                      takerAddress: string,
-                                     orderTransactionOpts?: OrderTransactionOpts): Promise<string> {
+                                     orderTransactionOpts: OrderTransactionOpts = {}): Promise<string> {
         assert.doesConformToSchema('signedOrders', signedOrders, schemas.signedOrdersSchema);
         const takerTokenAddresses = _.map(signedOrders, signedOrder => signedOrder.takerTokenAddress);
         assert.hasAtMostOneUniqueValue(takerTokenAddresses,
@@ -239,16 +233,20 @@ export class ExchangeWrapper extends ContractWrapper {
         const exchangeContractAddresses = _.map(signedOrders, signedOrder => signedOrder.exchangeContractAddress);
         assert.hasAtMostOneUniqueValue(exchangeContractAddresses,
                                        ExchangeContractErrs.BatchOrdersMustHaveSameExchangeAddress);
-        assert.isBigNumber('fillTakerTokenAmount', fillTakerTokenAmount);
+        assert.isValidBaseUnitAmount('fillTakerTokenAmount', fillTakerTokenAmount);
         assert.isBoolean('shouldThrowOnInsufficientBalanceOrAllowance', shouldThrowOnInsufficientBalanceOrAllowance);
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
 
-        const shouldValidate = _.isUndefined(orderTransactionOpts) ?
-            SHOULD_VALIDATE_BY_DEFAULT :
-            orderTransactionOpts.shouldValidate;
+        const shouldValidate = _.isUndefined(orderTransactionOpts.shouldValidate) ?
+                               SHOULD_VALIDATE_BY_DEFAULT :
+                               orderTransactionOpts.shouldValidate;
         if (shouldValidate) {
-            await Promise.all(signedOrders.map(signedOrder => this.validateFillOrderThrowIfInvalidAsync(
-                signedOrder, fillTakerTokenAmount, takerAddress)));
+            const zrxTokenAddress = this.getZRXTokenAddress();
+            const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+            for (const signedOrder of signedOrders) {
+                await this._orderValidationUtils.validateFillOrderThrowIfInvalidAsync(
+                    exchangeTradeEmulator, signedOrder, fillTakerTokenAmount, takerAddress, zrxTokenAddress);
+            }
         }
 
         if (_.isEmpty(signedOrders)) {
@@ -269,18 +267,6 @@ export class ExchangeWrapper extends ContractWrapper {
         );
 
         const exchangeInstance = await this._getExchangeContractAsync();
-        const gas = await exchangeInstance.fillOrdersUpTo.estimateGasAsync(
-            orderAddressesArray,
-            orderValuesArray,
-            fillTakerTokenAmount,
-            shouldThrowOnInsufficientBalanceOrAllowance,
-            vArray,
-            rArray,
-            sArray,
-            {
-                from: takerAddress,
-            },
-        );
         const txHash = await exchangeInstance.fillOrdersUpTo.sendTransactionAsync(
             orderAddressesArray,
             orderValuesArray,
@@ -291,7 +277,8 @@ export class ExchangeWrapper extends ContractWrapper {
             sArray,
             {
                 from: takerAddress,
-                gas,
+                gas: orderTransactionOpts.gasLimit,
+                gasPrice: orderTransactionOpts.gasPrice,
             },
         );
         return txHash;
@@ -299,9 +286,9 @@ export class ExchangeWrapper extends ContractWrapper {
     /**
      * Batch version of fillOrderAsync.
      * Executes multiple fills atomically in a single transaction.
-     * If shouldThrowOnInsufficientBalanceOrAllowance is set to true, it will continue filling subsequent orders even
+     * If shouldThrowOnInsufficientBalanceOrAllowance is set to false, it will continue filling subsequent orders even
      * when earlier ones fail.
-     * When shouldThrowOnInsufficientBalanceOrAllowance is set to false, if any fill fails, the entire batch fails.
+     * When shouldThrowOnInsufficientBalanceOrAllowance is set to true, if any fill fails, the entire batch fails.
      * @param   orderFillRequests                               An array of objects that conform to the
      *                                                          OrderFillRequest interface.
      * @param   shouldThrowOnInsufficientBalanceOrAllowance     Whether or not you wish for the contract call to throw
@@ -319,7 +306,7 @@ export class ExchangeWrapper extends ContractWrapper {
     public async batchFillOrdersAsync(orderFillRequests: OrderFillRequest[],
                                       shouldThrowOnInsufficientBalanceOrAllowance: boolean,
                                       takerAddress: string,
-                                      orderTransactionOpts?: OrderTransactionOpts): Promise<string> {
+                                      orderTransactionOpts: OrderTransactionOpts = {}): Promise<string> {
         assert.doesConformToSchema('orderFillRequests', orderFillRequests, schemas.orderFillRequestsSchema);
         const exchangeContractAddresses = _.map(
             orderFillRequests,
@@ -329,13 +316,18 @@ export class ExchangeWrapper extends ContractWrapper {
                                        ExchangeContractErrs.BatchOrdersMustHaveSameExchangeAddress);
         assert.isBoolean('shouldThrowOnInsufficientBalanceOrAllowance', shouldThrowOnInsufficientBalanceOrAllowance);
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
-        const shouldValidate = _.isUndefined(orderTransactionOpts) ?
-            SHOULD_VALIDATE_BY_DEFAULT :
-            orderTransactionOpts.shouldValidate;
+        const shouldValidate = _.isUndefined(orderTransactionOpts.shouldValidate) ?
+                               SHOULD_VALIDATE_BY_DEFAULT :
+                               orderTransactionOpts.shouldValidate;
         if (shouldValidate) {
-            await Promise.all(orderFillRequests.map(orderFillRequest => this.validateFillOrderThrowIfInvalidAsync(
-                orderFillRequest.signedOrder, orderFillRequest.takerTokenFillAmount, takerAddress)),
-            );
+            const zrxTokenAddress = this.getZRXTokenAddress();
+            const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+            for (const orderFillRequest of orderFillRequests) {
+                await this._orderValidationUtils.validateFillOrderThrowIfInvalidAsync(
+                    exchangeTradeEmulator, orderFillRequest.signedOrder, orderFillRequest.takerTokenFillAmount,
+                    takerAddress, zrxTokenAddress,
+                );
+            }
         }
         if (_.isEmpty(orderFillRequests)) {
             throw new Error(ExchangeContractErrs.BatchOrdersMustHaveAtLeastOneItem);
@@ -356,18 +348,6 @@ export class ExchangeWrapper extends ContractWrapper {
         );
 
         const exchangeInstance = await this._getExchangeContractAsync();
-        const gas = await exchangeInstance.batchFillOrders.estimateGasAsync(
-            orderAddressesArray,
-            orderValuesArray,
-            fillTakerTokenAmounts,
-            shouldThrowOnInsufficientBalanceOrAllowance,
-            vArray,
-            rArray,
-            sArray,
-            {
-                from: takerAddress,
-            },
-        );
         const txHash = await exchangeInstance.batchFillOrders.sendTransactionAsync(
             orderAddressesArray,
             orderValuesArray,
@@ -378,7 +358,8 @@ export class ExchangeWrapper extends ContractWrapper {
             sArray,
             {
                 from: takerAddress,
-                gas,
+                gas: orderTransactionOpts.gasLimit,
+                gasPrice: orderTransactionOpts.gasPrice,
             },
         );
         return txHash;
@@ -395,35 +376,26 @@ export class ExchangeWrapper extends ContractWrapper {
      * @return  Transaction hash.
      */
     @decorators.contractCallErrorHandler
-    public async fillOrKillOrderAsync(signedOrder: SignedOrder, fillTakerTokenAmount: BigNumber.BigNumber,
+    public async fillOrKillOrderAsync(signedOrder: SignedOrder, fillTakerTokenAmount: BigNumber,
                                       takerAddress: string,
-                                      orderTransactionOpts?: OrderTransactionOpts): Promise<string> {
+                                      orderTransactionOpts: OrderTransactionOpts = {}): Promise<string> {
         assert.doesConformToSchema('signedOrder', signedOrder, schemas.signedOrderSchema);
-        assert.isBigNumber('fillTakerTokenAmount', fillTakerTokenAmount);
+        assert.isValidBaseUnitAmount('fillTakerTokenAmount', fillTakerTokenAmount);
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
 
         const exchangeInstance = await this._getExchangeContractAsync();
 
-        const shouldValidate = _.isUndefined(orderTransactionOpts) ?
-            SHOULD_VALIDATE_BY_DEFAULT :
-            orderTransactionOpts.shouldValidate;
+        const shouldValidate = _.isUndefined(orderTransactionOpts.shouldValidate) ?
+                               SHOULD_VALIDATE_BY_DEFAULT :
+                               orderTransactionOpts.shouldValidate;
         if (shouldValidate) {
-            await this.validateFillOrKillOrderThrowIfInvalidAsync(signedOrder, fillTakerTokenAmount, takerAddress);
+            const zrxTokenAddress = this.getZRXTokenAddress();
+            const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+            await this._orderValidationUtils.validateFillOrKillOrderThrowIfInvalidAsync(
+                exchangeTradeEmulator, signedOrder, fillTakerTokenAmount, takerAddress, zrxTokenAddress);
         }
 
         const [orderAddresses, orderValues] = ExchangeWrapper._getOrderAddressesAndValues(signedOrder);
-
-        const gas = await exchangeInstance.fillOrKillOrder.estimateGasAsync(
-            orderAddresses,
-            orderValues,
-            fillTakerTokenAmount,
-            signedOrder.ecSignature.v,
-            signedOrder.ecSignature.r,
-            signedOrder.ecSignature.s,
-            {
-                from: takerAddress,
-            },
-        );
         const txHash = await exchangeInstance.fillOrKillOrder.sendTransactionAsync(
             orderAddresses,
             orderValues,
@@ -433,7 +405,8 @@ export class ExchangeWrapper extends ContractWrapper {
             signedOrder.ecSignature.s,
             {
                 from: takerAddress,
-                gas,
+                gas: orderTransactionOpts.gasLimit,
+                gasPrice: orderTransactionOpts.gasPrice,
             },
         );
         return txHash;
@@ -441,43 +414,48 @@ export class ExchangeWrapper extends ContractWrapper {
     /**
      * Batch version of fillOrKill. Allows a taker to specify a batch of orders that will either be atomically
      * filled (each to the specified fillAmount) or aborted.
-     * @param   orderFillOrKillRequests     An array of objects that conform to the OrderFillOrKillRequest interface.
+     * @param   orderFillRequests           An array of objects that conform to the OrderFillRequest interface.
      * @param   takerAddress                The user Ethereum address who would like to fill there orders.
      *                                      Must be available via the supplied Web3.Provider passed to 0x.js.
      * @param   orderTransactionOpts        Optional arguments this method accepts.
      * @return  Transaction hash.
      */
     @decorators.contractCallErrorHandler
-    public async batchFillOrKillAsync(orderFillOrKillRequests: OrderFillOrKillRequest[],
+    public async batchFillOrKillAsync(orderFillRequests: OrderFillRequest[],
                                       takerAddress: string,
-                                      orderTransactionOpts?: OrderTransactionOpts): Promise<string> {
-        assert.doesConformToSchema('orderFillOrKillRequests', orderFillOrKillRequests,
-                                   schemas.orderFillOrKillRequestsSchema);
+                                      orderTransactionOpts: OrderTransactionOpts = {}): Promise<string> {
+        assert.doesConformToSchema('orderFillRequests', orderFillRequests,
+                                   schemas.orderFillRequestsSchema);
         const exchangeContractAddresses = _.map(
-            orderFillOrKillRequests,
-            orderFillOrKillRequest => orderFillOrKillRequest.signedOrder.exchangeContractAddress,
+            orderFillRequests,
+            orderFillRequest => orderFillRequest.signedOrder.exchangeContractAddress,
         );
         assert.hasAtMostOneUniqueValue(exchangeContractAddresses,
                                        ExchangeContractErrs.BatchOrdersMustHaveSameExchangeAddress);
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
-        if (_.isEmpty(orderFillOrKillRequests)) {
+        if (_.isEmpty(orderFillRequests)) {
             throw new Error(ExchangeContractErrs.BatchOrdersMustHaveAtLeastOneItem);
         }
         const exchangeInstance = await this._getExchangeContractAsync();
 
-        const shouldValidate = _.isUndefined(orderTransactionOpts) ?
-            SHOULD_VALIDATE_BY_DEFAULT :
-            orderTransactionOpts.shouldValidate;
+        const shouldValidate = _.isUndefined(orderTransactionOpts.shouldValidate) ?
+                               SHOULD_VALIDATE_BY_DEFAULT :
+                               orderTransactionOpts.shouldValidate;
         if (shouldValidate) {
-            await Promise.all(orderFillOrKillRequests.map(request => this.validateFillOrKillOrderThrowIfInvalidAsync(
-                request.signedOrder, request.fillTakerAmount, takerAddress)),
-            );
+            const zrxTokenAddress = this.getZRXTokenAddress();
+            const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
+            for (const orderFillRequest of orderFillRequests) {
+                await this._orderValidationUtils.validateFillOrKillOrderThrowIfInvalidAsync(
+                    exchangeTradeEmulator, orderFillRequest.signedOrder, orderFillRequest.takerTokenFillAmount,
+                    takerAddress, zrxTokenAddress,
+                );
+            }
         }
 
-        const orderAddressesValuesAndTakerTokenFillAmounts = _.map(orderFillOrKillRequests, request => {
+        const orderAddressesValuesAndTakerTokenFillAmounts = _.map(orderFillRequests, request => {
             return [
                 ...ExchangeWrapper._getOrderAddressesAndValues(request.signedOrder),
-                request.fillTakerAmount,
+                request.takerTokenFillAmount,
                 request.signedOrder.ecSignature.v,
                 request.signedOrder.ecSignature.r,
                 request.signedOrder.ecSignature.s,
@@ -487,18 +465,6 @@ export class ExchangeWrapper extends ContractWrapper {
         // We use _.unzip<any> because _.unzip doesn't type check if values have different types :'(
         const [orderAddresses, orderValues, fillTakerTokenAmounts, vParams, rParams, sParams] =
               _.unzip<any>(orderAddressesValuesAndTakerTokenFillAmounts);
-
-        const gas = await exchangeInstance.batchFillOrKillOrders.estimateGasAsync(
-            orderAddresses,
-            orderValues,
-            fillTakerTokenAmounts,
-            vParams,
-            rParams,
-            sParams,
-            {
-                from: takerAddress,
-            },
-        );
         const txHash = await exchangeInstance.batchFillOrKillOrders.sendTransactionAsync(
             orderAddresses,
             orderValues,
@@ -508,7 +474,8 @@ export class ExchangeWrapper extends ContractWrapper {
             sParams,
             {
                 from: takerAddress,
-                gas,
+                gas: orderTransactionOpts.gasLimit,
+                gasPrice: orderTransactionOpts.gasPrice,
             },
         );
         return txHash;
@@ -523,37 +490,33 @@ export class ExchangeWrapper extends ContractWrapper {
      */
     @decorators.contractCallErrorHandler
     public async cancelOrderAsync(order: Order|SignedOrder,
-                                  cancelTakerTokenAmount: BigNumber.BigNumber,
-                                  orderTransactionOpts?: OrderTransactionOpts): Promise<string> {
+                                  cancelTakerTokenAmount: BigNumber,
+                                  orderTransactionOpts: OrderTransactionOpts = {}): Promise<string> {
         assert.doesConformToSchema('order', order, schemas.orderSchema);
-        assert.isBigNumber('takerTokenCancelAmount', cancelTakerTokenAmount);
+        assert.isValidBaseUnitAmount('takerTokenCancelAmount', cancelTakerTokenAmount);
         await assert.isSenderAddressAsync('order.maker', order.maker, this._web3Wrapper);
 
         const exchangeInstance = await this._getExchangeContractAsync();
 
-        const shouldValidate = _.isUndefined(orderTransactionOpts) ?
-            SHOULD_VALIDATE_BY_DEFAULT :
-            orderTransactionOpts.shouldValidate;
+        const shouldValidate = _.isUndefined(orderTransactionOpts.shouldValidate) ?
+                               SHOULD_VALIDATE_BY_DEFAULT :
+                               orderTransactionOpts.shouldValidate;
         if (shouldValidate) {
-            await this.validateCancelOrderThrowIfInvalidAsync(order, cancelTakerTokenAmount);
+            const orderHash = utils.getOrderHashHex(order);
+            const unavailableTakerTokenAmount = await this.getUnavailableTakerAmountAsync(orderHash);
+            OrderValidationUtils.validateCancelOrderThrowIfInvalid(
+                order, cancelTakerTokenAmount, unavailableTakerTokenAmount);
         }
 
         const [orderAddresses, orderValues] = ExchangeWrapper._getOrderAddressesAndValues(order);
-        const gas = await exchangeInstance.cancelOrder.estimateGasAsync(
-            orderAddresses,
-            orderValues,
-            cancelTakerTokenAmount,
-            {
-                from: order.maker,
-            },
-        );
         const txHash = await exchangeInstance.cancelOrder.sendTransactionAsync(
             orderAddresses,
             orderValues,
             cancelTakerTokenAmount,
             {
                 from: order.maker,
-                gas,
+                gas: orderTransactionOpts.gasLimit,
+                gasPrice: orderTransactionOpts.gasPrice,
             },
         );
         return txHash;
@@ -568,7 +531,7 @@ export class ExchangeWrapper extends ContractWrapper {
      */
     @decorators.contractCallErrorHandler
     public async batchCancelOrdersAsync(orderCancellationRequests: OrderCancellationRequest[],
-                                        orderTransactionOpts?: OrderTransactionOpts): Promise<string> {
+                                        orderTransactionOpts: OrderTransactionOpts = {}): Promise<string> {
         assert.doesConformToSchema('orderCancellationRequests', orderCancellationRequests,
                                    schemas.orderCancellationRequestsSchema);
         const exchangeContractAddresses = _.map(
@@ -581,13 +544,19 @@ export class ExchangeWrapper extends ContractWrapper {
         assert.hasAtMostOneUniqueValue(makers, ExchangeContractErrs.MultipleMakersInSingleCancelBatchDisallowed);
         const maker = makers[0];
         await assert.isSenderAddressAsync('maker', maker, this._web3Wrapper);
-        const shouldValidate = _.isUndefined(orderTransactionOpts) ?
-            SHOULD_VALIDATE_BY_DEFAULT :
-            orderTransactionOpts.shouldValidate;
+        const shouldValidate = _.isUndefined(orderTransactionOpts.shouldValidate) ?
+                               SHOULD_VALIDATE_BY_DEFAULT :
+                               orderTransactionOpts.shouldValidate;
         if (shouldValidate) {
-            await Promise.all(orderCancellationRequests.map(cancellationRequest =>
-                this.validateCancelOrderThrowIfInvalidAsync(
-                    cancellationRequest.order, cancellationRequest.takerTokenCancelAmount)));
+            for (const orderCancellationRequest of orderCancellationRequests) {
+                const orderHash = utils.getOrderHashHex(orderCancellationRequest.order);
+                const unavailableTakerTokenAmount = await this.getUnavailableTakerAmountAsync(orderHash);
+                OrderValidationUtils.validateCancelOrderThrowIfInvalid(
+                    orderCancellationRequest.order, orderCancellationRequest.takerTokenCancelAmount,
+                    unavailableTakerTokenAmount,
+                );
+            }
+
         }
         if (_.isEmpty(orderCancellationRequests)) {
             throw new Error(ExchangeContractErrs.BatchOrdersMustHaveAtLeastOneItem);
@@ -602,61 +571,44 @@ export class ExchangeWrapper extends ContractWrapper {
         // We use _.unzip<any> because _.unzip doesn't type check if values have different types :'(
         const [orderAddresses, orderValues, cancelTakerTokenAmounts] =
             _.unzip<any>(orderAddressesValuesAndTakerTokenCancelAmounts);
-        const gas = await exchangeInstance.batchCancelOrders.estimateGasAsync(
-            orderAddresses,
-            orderValues,
-            cancelTakerTokenAmounts,
-            {
-                from: maker,
-            },
-        );
         const txHash = await exchangeInstance.batchCancelOrders.sendTransactionAsync(
             orderAddresses,
             orderValues,
             cancelTakerTokenAmounts,
             {
                 from: maker,
-                gas,
+                gas: orderTransactionOpts.gasLimit,
+                gasPrice: orderTransactionOpts.gasPrice,
             },
         );
         return txHash;
     }
     /**
-     * Subscribe to an event type emitted by the Exchange smart contract
-     * @param   eventName               The exchange contract event you would like to subscribe to.
-     * @param   subscriptionOpts        Subscriptions options that let you configure the subscription.
-     * @param   indexFilterValues       An object where the keys are indexed args returned by the event and
-     *                                  the value is the value you are interested in. E.g `{maker: aUserAddressHex}`
-     * @param   exchangeContractAddress The hex encoded address of the Exchange contract to call.
-     * @return                      ContractEventEmitter object
+     * Subscribe to an event type emitted by the Exchange contract.
+     * @param   eventName           The exchange contract event you would like to subscribe to.
+     * @param   indexFilterValues   An object where the keys are indexed args returned by the event and
+     *                              the value is the value you are interested in. E.g `{maker: aUserAddressHex}`
+     * @param   callback            Callback that gets called when a log is added/removed
+     * @return Subscription token used later to unsubscribe
      */
-    public async subscribeAsync(eventName: ExchangeEvents, subscriptionOpts: SubscriptionOpts,
-                                indexFilterValues: IndexedFilterValues, exchangeContractAddress: string):
-                                Promise<ContractEventEmitter> {
-        assert.isETHAddressHex('exchangeContractAddress', exchangeContractAddress);
+    public subscribe<ArgsType extends ExchangeContractEventArgs>(
+        eventName: ExchangeEvents, indexFilterValues: IndexedFilterValues,
+        callback: EventCallback<ArgsType>): string {
         assert.doesBelongToStringEnum('eventName', eventName, ExchangeEvents);
-        assert.doesConformToSchema('subscriptionOpts', subscriptionOpts, schemas.subscriptionOptsSchema);
         assert.doesConformToSchema('indexFilterValues', indexFilterValues, schemas.indexFilterValuesSchema);
-        const exchangeContract = await this._getExchangeContractAsync();
-        let createLogEvent: CreateContractEvent;
-        switch (eventName) {
-            case ExchangeEvents.LogFill:
-                createLogEvent = exchangeContract.LogFill;
-                break;
-            case ExchangeEvents.LogError:
-                createLogEvent = exchangeContract.LogError;
-                break;
-            case ExchangeEvents.LogCancel:
-                createLogEvent = exchangeContract.LogCancel;
-                break;
-            default:
-                throw utils.spawnSwitchErr('ExchangeEvents', eventName);
-        }
-
-        const logEventObj: ContractEventObj = createLogEvent(indexFilterValues, subscriptionOpts);
-        const eventEmitter = eventUtils.wrapEventEmitter(logEventObj);
-        this._exchangeLogEventEmitters.push(eventEmitter);
-        return eventEmitter;
+        assert.isFunction('callback', callback);
+        const exchangeContractAddress = this.getContractAddress();
+        const subscriptionToken = this._subscribe<ArgsType>(
+            exchangeContractAddress, eventName, indexFilterValues, artifacts.ExchangeArtifact.abi, callback,
+        );
+        return subscriptionToken;
+    }
+    /**
+     * Cancel a subscription
+     * @param   subscriptionToken Subscription token returned by `subscribe()`
+     */
+    public unsubscribe(subscriptionToken: string): void {
+        this._unsubscribe(subscriptionToken);
     }
     /**
      * Gets historical logs without creating a subscription
@@ -666,35 +618,26 @@ export class ExchangeWrapper extends ContractWrapper {
      *                              the value is the value you are interested in. E.g `{_from: aUserAddressHex}`
      * @return  Array of logs that match the parameters
      */
-    public async getLogsAsync(eventName: ExchangeEvents, subscriptionOpts: SubscriptionOpts,
-                              indexFilterValues: IndexedFilterValues): Promise<LogWithDecodedArgs[]> {
+    public async getLogsAsync<ArgsType extends ExchangeContractEventArgs>(
+        eventName: ExchangeEvents, subscriptionOpts: SubscriptionOpts, indexFilterValues: IndexedFilterValues,
+    ): Promise<Array<LogWithDecodedArgs<ArgsType>>> {
         assert.doesBelongToStringEnum('eventName', eventName, ExchangeEvents);
         assert.doesConformToSchema('subscriptionOpts', subscriptionOpts, schemas.subscriptionOptsSchema);
         assert.doesConformToSchema('indexFilterValues', indexFilterValues, schemas.indexFilterValuesSchema);
-        const exchangeContractAddress = await this.getContractAddressAsync();
-        const logs = await this._getLogsAsync(
+        const exchangeContractAddress = this.getContractAddress();
+        const logs = await this._getLogsAsync<ArgsType>(
             exchangeContractAddress, eventName, subscriptionOpts, indexFilterValues, artifacts.ExchangeArtifact.abi,
         );
         return logs;
     }
-    /**
-     * Stops watching for all exchange events
-     */
-    public async stopWatchingAllEventsAsync(): Promise<void> {
-        const stopWatchingPromises = _.map(this._exchangeLogEventEmitters,
-                                           logEventObj => logEventObj.stopWatchingAsync());
-        await Promise.all(stopWatchingPromises);
-        this._exchangeLogEventEmitters = [];
-    }
     /**
      * Retrieves the Ethereum address of the Exchange contract deployed on the network
      * that the user-passed web3 provider is connected to.
      * @returns The Ethereum address of the Exchange contract being used.
      */
-    public async getContractAddressAsync(): Promise<string> {
-        const exchangeInstance = await this._getExchangeContractAsync();
-        const exchangeAddress = exchangeInstance.address;
-        return exchangeAddress;
+    public getContractAddress(): string {
+        const contractAddress = this._getContractAddress(artifacts.ExchangeArtifact, this._contractAddressIfExists);
+        return contractAddress;
     }
     /**
      * Checks if order is still fillable and throws an error otherwise. Useful for orderbook
@@ -709,10 +652,11 @@ export class ExchangeWrapper extends ContractWrapper {
         signedOrder: SignedOrder, opts?: ValidateOrderFillableOpts,
     ): Promise<void> {
         assert.doesConformToSchema('signedOrder', signedOrder, schemas.signedOrderSchema);
-        const zrxTokenAddress = await this.getZRXTokenAddressAsync();
+        const zrxTokenAddress = this.getZRXTokenAddress();
         const expectedFillTakerTokenAmount = !_.isUndefined(opts) ? opts.expectedFillTakerTokenAmount : undefined;
+        const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
         await this._orderValidationUtils.validateOrderFillableOrThrowAsync(
-            signedOrder, zrxTokenAddress, expectedFillTakerTokenAmount,
+            exchangeTradeEmulator, signedOrder, zrxTokenAddress, expectedFillTakerTokenAmount,
         );
     }
     /**
@@ -724,14 +668,15 @@ export class ExchangeWrapper extends ContractWrapper {
      *                                  Must be available via the supplied Web3.Provider passed to 0x.js.
      */
     public async validateFillOrderThrowIfInvalidAsync(signedOrder: SignedOrder,
-                                                      fillTakerTokenAmount: BigNumber.BigNumber,
+                                                      fillTakerTokenAmount: BigNumber,
                                                       takerAddress: string): Promise<void> {
         assert.doesConformToSchema('signedOrder', signedOrder, schemas.signedOrderSchema);
-        assert.isBigNumber('fillTakerTokenAmount', fillTakerTokenAmount);
+        assert.isValidBaseUnitAmount('fillTakerTokenAmount', fillTakerTokenAmount);
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
-        const zrxTokenAddress = await this.getZRXTokenAddressAsync();
+        const zrxTokenAddress = this.getZRXTokenAddress();
+        const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
         await this._orderValidationUtils.validateFillOrderThrowIfInvalidAsync(
-            signedOrder, fillTakerTokenAmount, takerAddress, zrxTokenAddress);
+            exchangeTradeEmulator, signedOrder, fillTakerTokenAmount, takerAddress, zrxTokenAddress);
     }
     /**
      * Checks if cancelling a given order will succeed and throws an informative error if it won't.
@@ -740,12 +685,12 @@ export class ExchangeWrapper extends ContractWrapper {
      * @param   cancelTakerTokenAmount  The amount (specified in taker tokens) that you would like to cancel.
      */
     public async validateCancelOrderThrowIfInvalidAsync(
-        order: Order, cancelTakerTokenAmount: BigNumber.BigNumber): Promise<void> {
+        order: Order, cancelTakerTokenAmount: BigNumber): Promise<void> {
         assert.doesConformToSchema('order', order, schemas.orderSchema);
-        assert.isBigNumber('cancelTakerTokenAmount', cancelTakerTokenAmount);
+        assert.isValidBaseUnitAmount('cancelTakerTokenAmount', cancelTakerTokenAmount);
         const orderHash = utils.getOrderHashHex(order);
         const unavailableTakerTokenAmount = await this.getUnavailableTakerAmountAsync(orderHash);
-        await this._orderValidationUtils.validateCancelOrderThrowIfInvalidAsync(
+        OrderValidationUtils.validateCancelOrderThrowIfInvalid(
             order, cancelTakerTokenAmount, unavailableTakerTokenAmount);
     }
     /**
@@ -757,14 +702,15 @@ export class ExchangeWrapper extends ContractWrapper {
      *                                  Must be available via the supplied Web3.Provider passed to 0x.js.
      */
     public async validateFillOrKillOrderThrowIfInvalidAsync(signedOrder: SignedOrder,
-                                                            fillTakerTokenAmount: BigNumber.BigNumber,
+                                                            fillTakerTokenAmount: BigNumber,
                                                             takerAddress: string): Promise<void> {
         assert.doesConformToSchema('signedOrder', signedOrder, schemas.signedOrderSchema);
-        assert.isBigNumber('fillTakerTokenAmount', fillTakerTokenAmount);
+        assert.isValidBaseUnitAmount('fillTakerTokenAmount', fillTakerTokenAmount);
         await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
-        const zrxTokenAddress = await this.getZRXTokenAddressAsync();
+        const zrxTokenAddress = this.getZRXTokenAddress();
+        const exchangeTradeEmulator = new ExchangeTransferSimulator(this._tokenWrapper, BlockParamLiteral.Latest);
         await this._orderValidationUtils.validateFillOrKillOrderThrowIfInvalidAsync(
-            signedOrder, fillTakerTokenAmount, takerAddress, zrxTokenAddress);
+            exchangeTradeEmulator, signedOrder, fillTakerTokenAmount, takerAddress, zrxTokenAddress);
     }
     /**
      * Checks if rounding error will be > 0.1% when computing makerTokenAmount by doing:
@@ -775,12 +721,12 @@ export class ExchangeWrapper extends ContractWrapper {
      * @param   takerTokenAmount       The order size on the taker side
      * @param   makerTokenAmount       The order size on the maker side
      */
-    public async isRoundingErrorAsync(fillTakerTokenAmount: BigNumber.BigNumber,
-                                      takerTokenAmount: BigNumber.BigNumber,
-                                      makerTokenAmount: BigNumber.BigNumber): Promise<boolean> {
-        assert.isBigNumber('fillTakerTokenAmount', fillTakerTokenAmount);
-        assert.isBigNumber('takerTokenAmount', takerTokenAmount);
-        assert.isBigNumber('makerTokenAmount', makerTokenAmount);
+    public async isRoundingErrorAsync(fillTakerTokenAmount: BigNumber,
+                                      takerTokenAmount: BigNumber,
+                                      makerTokenAmount: BigNumber): Promise<boolean> {
+        assert.isValidBaseUnitAmount('fillTakerTokenAmount', fillTakerTokenAmount);
+        assert.isValidBaseUnitAmount('takerTokenAmount', takerTokenAmount);
+        assert.isValidBaseUnitAmount('makerTokenAmount', makerTokenAmount);
         const exchangeInstance = await this._getExchangeContractAsync();
         const isRoundingError = await exchangeInstance.isRoundingError.callAsync(
             fillTakerTokenAmount, takerTokenAmount, makerTokenAmount,
@@ -789,12 +735,14 @@ export class ExchangeWrapper extends ContractWrapper {
     }
     /**
      * Checks if logs contain LogError, which is emmited by Exchange contract on transaction failure.
-     * @param   logsWithDecodedArgs   Transaction logs as returned by `zeroEx.awaitTransactionMinedAsync`
+     * @param   logs   Transaction logs as returned by `zeroEx.awaitTransactionMinedAsync`
      */
-    public throwLogErrorsAsErrors(logsWithDecodedArgs: LogWithDecodedArgs[]): void {
-        const errLog = _.find(logsWithDecodedArgs, {event: ExchangeEvents.LogError});
+    public throwLogErrorsAsErrors(logs: Array<LogWithDecodedArgs<DecodedLogArgs>|Web3.LogEntry>): void {
+        const errLog = _.find(logs, {
+            event: ExchangeEvents.LogError,
+        }) as LogWithDecodedArgs<LogErrorContractEventArgs>|undefined;
         if (!_.isUndefined(errLog)) {
-            const logArgs: LogErrorContractEventArgs = errLog.args as any;
+            const logArgs = errLog.args;
             const errCode = logArgs.errorId.toNumber();
             const errMessage = this._exchangeContractErrCodesToMsg[errCode];
             throw new Error(errMessage);
@@ -804,13 +752,14 @@ export class ExchangeWrapper extends ContractWrapper {
      * Returns the ZRX token address used by the exchange contract.
      * @return Address of ZRX token
      */
-    public async getZRXTokenAddressAsync(): Promise<string> {
-        const exchangeInstance = await this._getExchangeContractAsync();
-        const ZRXtokenAddress = await exchangeInstance.ZRX_TOKEN_CONTRACT.callAsync();
-        return ZRXtokenAddress;
+    public getZRXTokenAddress(): string {
+        const contractAddress = this._getContractAddress(
+            artifacts.ZRXArtifact, this._zrxContractAddressIfExists,
+        );
+        return contractAddress;
     }
-    private async _invalidateContractInstancesAsync(): Promise<void> {
-        await this.stopWatchingAllEventsAsync();
+    private _invalidateContractInstances(): void {
+        this.unsubscribeAll();
         delete this._exchangeContractIfExists;
     }
     private async _isValidSignatureUsingContractCallAsync(dataHex: string, ecSignature: ECSignature,
@@ -843,7 +792,7 @@ export class ExchangeWrapper extends ContractWrapper {
         const contractInstance = await this._instantiateContractIfExistsAsync<ExchangeContract>(
             artifacts.ExchangeArtifact, this._contractAddressIfExists,
         );
-        this._exchangeContractIfExists = contractInstance as ExchangeContract;
+        this._exchangeContractIfExists = contractInstance;
         return this._exchangeContractIfExists;
     }
     private async _getTokenTransferProxyAddressAsync(): Promise<string> {
@@ -852,4 +801,4 @@ export class ExchangeWrapper extends ContractWrapper {
         const tokenTransferProxyAddressLowerCase = tokenTransferProxyAddress.toLowerCase();
         return tokenTransferProxyAddressLowerCase;
     }
-}
+} // tslint:disable:max-file-line-count

packages/0x.js/src/contract_wrappers/token_registry_wrapper.ts

@@ -1,10 +1,12 @@
 import * as _ from 'lodash';
-import {Web3Wrapper} from '../web3_wrapper';
-import {assert} from '../utils/assert';
-import {Token, TokenRegistryContract, TokenMetadata} from '../types';
-import {constants} from '../utils/constants';
-import {ContractWrapper} from './contract_wrapper';
+
 import {artifacts} from '../artifacts';
+import {Token, TokenMetadata, TokenRegistryContract, ZeroExError} from '../types';
+import {assert} from '../utils/assert';
+import {constants} from '../utils/constants';
+import {Web3Wrapper} from '../web3_wrapper';
+
+import {ContractWrapper} from './contract_wrapper';
 
 /**
  * This class includes all the functionality related to interacting with the 0x Token Registry smart contract.
@@ -12,6 +14,18 @@ import {artifacts} from '../artifacts';
 export class TokenRegistryWrapper extends ContractWrapper {
     private _tokenRegistryContractIfExists?: TokenRegistryContract;
     private _contractAddressIfExists?: string;
+    private static _createTokenFromMetadata(metadata: TokenMetadata): Token|undefined {
+        if (metadata[0] === constants.NULL_ADDRESS) {
+            return undefined;
+        }
+        const token = {
+            address: metadata[0],
+            name: metadata[1],
+            symbol: metadata[2],
+            decimals: metadata[3].toNumber(),
+        };
+        return token;
+    }
     constructor(web3Wrapper: Web3Wrapper, contractAddressIfExists?: string) {
         super(web3Wrapper);
         this._contractAddressIfExists = contractAddressIfExists;
@@ -26,7 +40,7 @@ export class TokenRegistryWrapper extends ContractWrapper {
         const addresses = await this.getTokenAddressesAsync();
         const tokenPromises: Array<Promise<Token|undefined>> = _.map(
             addresses,
-            (address: string) => (this.getTokenIfExistsAsync(address)),
+            async (address: string) => this.getTokenIfExistsAsync(address),
         );
         const tokens = await Promise.all(tokenPromises);
         return tokens as Token[];
@@ -49,7 +63,7 @@ export class TokenRegistryWrapper extends ContractWrapper {
 
         const tokenRegistryContract = await this._getTokenRegistryContractAsync();
         const metadata = await tokenRegistryContract.getTokenMetaData.callAsync(address);
-        const token = this._createTokenFromMetadata(metadata);
+        const token = TokenRegistryWrapper._createTokenFromMetadata(metadata);
         return token;
     }
     public async getTokenAddressBySymbolIfExistsAsync(symbol: string): Promise<string|undefined> {
@@ -74,14 +88,14 @@ export class TokenRegistryWrapper extends ContractWrapper {
         assert.isString('symbol', symbol);
         const tokenRegistryContract = await this._getTokenRegistryContractAsync();
         const metadata = await tokenRegistryContract.getTokenBySymbol.callAsync(symbol);
-        const token = this._createTokenFromMetadata(metadata);
+        const token = TokenRegistryWrapper._createTokenFromMetadata(metadata);
         return token;
     }
     public async getTokenByNameIfExistsAsync(name: string): Promise<Token|undefined> {
         assert.isString('name', name);
         const tokenRegistryContract = await this._getTokenRegistryContractAsync();
         const metadata = await tokenRegistryContract.getTokenByName.callAsync(name);
-        const token = this._createTokenFromMetadata(metadata);
+        const token = TokenRegistryWrapper._createTokenFromMetadata(metadata);
         return token;
     }
     /**
@@ -89,22 +103,11 @@ export class TokenRegistryWrapper extends ContractWrapper {
      * that the user-passed web3 provider is connected to.
      * @returns The Ethereum address of the TokenRegistry contract being used.
      */
-    public async getContractAddressAsync(): Promise<string> {
-        const tokenRegistryInstance = await this._getTokenRegistryContractAsync();
-        const tokenRegistryAddress = tokenRegistryInstance.address;
-        return tokenRegistryAddress;
-    }
-    private _createTokenFromMetadata(metadata: TokenMetadata): Token|undefined {
-        if (metadata[0] === constants.NULL_ADDRESS) {
-            return undefined;
-        }
-        const token = {
-            address: metadata[0],
-            name: metadata[1],
-            symbol: metadata[2],
-            decimals: metadata[3].toNumber(),
-        };
-        return token;
+    public getContractAddress(): string {
+        const contractAddress = this._getContractAddress(
+            artifacts.TokenRegistryArtifact, this._contractAddressIfExists,
+        );
+        return contractAddress;
     }
     private _invalidateContractInstance(): void {
         delete this._tokenRegistryContractIfExists;
@@ -116,7 +119,7 @@ export class TokenRegistryWrapper extends ContractWrapper {
         const contractInstance = await this._instantiateContractIfExistsAsync<TokenRegistryContract>(
             artifacts.TokenRegistryArtifact, this._contractAddressIfExists,
         );
-        this._tokenRegistryContractIfExists = contractInstance as TokenRegistryContract;
+        this._tokenRegistryContractIfExists = contractInstance;
         return this._tokenRegistryContractIfExists;
     }
 }

packages/0x.js/src/contract_wrappers/token_transfer_proxy_wrapper.ts

@@ -1,18 +1,20 @@
 import * as _ from 'lodash';
-import {Web3Wrapper} from '../web3_wrapper';
-import {ContractWrapper} from './contract_wrapper';
+
 import {artifacts} from '../artifacts';
-import {TokenTransferProxyContract} from '../types';
+import {TokenTransferProxyContract, ZeroExError} from '../types';
+import {Web3Wrapper} from '../web3_wrapper';
+
+import {ContractWrapper} from './contract_wrapper';
 
 /**
  * This class includes the functionality related to interacting with the TokenTransferProxy contract.
  */
 export class TokenTransferProxyWrapper extends ContractWrapper {
     private _tokenTransferProxyContractIfExists?: TokenTransferProxyContract;
-    private _tokenTransferProxyContractAddressFetcher: () => Promise<string>;
-    constructor(web3Wrapper: Web3Wrapper, tokenTransferProxyContractAddressFetcher: () => Promise<string>) {
+    private _contractAddressIfExists?: string;
+    constructor(web3Wrapper: Web3Wrapper, contractAddressIfExists?: string) {
         super(web3Wrapper);
-        this._tokenTransferProxyContractAddressFetcher = tokenTransferProxyContractAddressFetcher;
+        this._contractAddressIfExists = contractAddressIfExists;
     }
     /**
      * Check if the Exchange contract address is authorized by the TokenTransferProxy contract.
@@ -38,10 +40,11 @@ export class TokenTransferProxyWrapper extends ContractWrapper {
      * that the user-passed web3 provider is connected to.
      * @returns The Ethereum address of the TokenTransferProxy contract being used.
      */
-    public async getContractAddressAsync(): Promise<string> {
-        const proxyInstance = await this._getTokenTransferProxyContractAsync();
-        const proxyAddress = proxyInstance.address;
-        return proxyAddress;
+    public getContractAddress(): string {
+        const contractAddress = this._getContractAddress(
+            artifacts.TokenTransferProxyArtifact, this._contractAddressIfExists,
+        );
+        return contractAddress;
     }
     private _invalidateContractInstance(): void {
         delete this._tokenTransferProxyContractIfExists;
@@ -50,11 +53,10 @@ export class TokenTransferProxyWrapper extends ContractWrapper {
         if (!_.isUndefined(this._tokenTransferProxyContractIfExists)) {
             return this._tokenTransferProxyContractIfExists;
         }
-        const contractAddress = await this._tokenTransferProxyContractAddressFetcher();
         const contractInstance = await this._instantiateContractIfExistsAsync<TokenTransferProxyContract>(
-            artifacts.TokenTransferProxyArtifact, contractAddress,
+            artifacts.TokenTransferProxyArtifact, this._contractAddressIfExists,
         );
-        this._tokenTransferProxyContractIfExists = contractInstance as TokenTransferProxyContract;
+        this._tokenTransferProxyContractIfExists = contractInstance;
         return this._tokenTransferProxyContractIfExists;
     }
 }

packages/0x.js/src/contract_wrappers/token_wrapper.ts

@@ -1,29 +1,29 @@
+import {schemas} from '@0xproject/json-schemas';
+import BigNumber from 'bignumber.js';
 import * as _ from 'lodash';
-import * as BigNumber from 'bignumber.js';
-import {SchemaValidator, schemas} from '0x-json-schemas';
-import {Web3Wrapper} from '../web3_wrapper';
-import {assert} from '../utils/assert';
-import {utils} from '../utils/utils';
-import {eventUtils} from '../utils/event_utils';
-import {constants} from '../utils/constants';
-import {ContractWrapper} from './contract_wrapper';
-import {AbiDecoder} from '../utils/abi_decoder';
+
 import {artifacts} from '../artifacts';
 import {
-    TokenContract,
-    ZeroExError,
-    TokenEvents,
+    EventCallback,
     IndexedFilterValues,
-    SubscriptionOpts,
-    CreateContractEvent,
-    ContractEventEmitter,
-    ContractEventObj,
-    MethodOpts,
     LogWithDecodedArgs,
-    RawLog,
+    MethodOpts,
+    SubscriptionOpts,
+    TokenContract,
+    TokenContractEventArgs,
+    TokenEvents,
+    TransactionOpts,
+    ZeroExError,
 } from '../types';
+import {AbiDecoder} from '../utils/abi_decoder';
+import {assert} from '../utils/assert';
+import {constants} from '../utils/constants';
+import {Web3Wrapper} from '../web3_wrapper';
 
-const ALLOWANCE_TO_ZERO_GAS_AMOUNT = 47155;
+import {ContractWrapper} from './contract_wrapper';
+import {TokenTransferProxyWrapper} from './token_transfer_proxy_wrapper';
+
+const ALLOWANCE_TO_ZERO_GAS_AMOUNT = 47275;
 
 /**
  * This class includes all the functionality related to interacting with ERC20 token contracts.
@@ -33,14 +33,12 @@ const ALLOWANCE_TO_ZERO_GAS_AMOUNT = 47155;
 export class TokenWrapper extends ContractWrapper {
     public UNLIMITED_ALLOWANCE_IN_BASE_UNITS = constants.UNLIMITED_ALLOWANCE_IN_BASE_UNITS;
     private _tokenContractsByAddress: {[address: string]: TokenContract};
-    private _tokenLogEventEmitters: ContractEventEmitter[];
-    private _tokenTransferProxyContractAddressFetcher: () => Promise<string>;
+    private _tokenTransferProxyWrapper: TokenTransferProxyWrapper;
     constructor(web3Wrapper: Web3Wrapper, abiDecoder: AbiDecoder,
-                tokenTransferProxyContractAddressFetcher: () => Promise<string>) {
+                tokenTransferProxyWrapper: TokenTransferProxyWrapper) {
         super(web3Wrapper, abiDecoder);
         this._tokenContractsByAddress = {};
-        this._tokenLogEventEmitters = [];
-        this._tokenTransferProxyContractAddressFetcher = tokenTransferProxyContractAddressFetcher;
+        this._tokenTransferProxyWrapper = tokenTransferProxyWrapper;
     }
     /**
      * Retrieves an owner's ERC20 token balance.
@@ -50,7 +48,7 @@ export class TokenWrapper extends ContractWrapper {
      * @return  The owner's ERC20 token balance in base units.
      */
     public async getBalanceAsync(tokenAddress: string, ownerAddress: string,
-                                 methodOpts?: MethodOpts): Promise<BigNumber.BigNumber> {
+                                 methodOpts?: MethodOpts): Promise<BigNumber> {
         assert.isETHAddressHex('ownerAddress', ownerAddress);
         assert.isETHAddressHex('tokenAddress', tokenAddress);
 
@@ -69,24 +67,21 @@ export class TokenWrapper extends ContractWrapper {
      *                              for spenderAddress.
      * @param   spenderAddress      The hex encoded user Ethereum address who will be able to spend the set allowance.
      * @param   amountInBaseUnits   The allowance amount you would like to set.
+     * @param   txOpts              Transaction parameters.
      * @return Transaction hash.
      */
     public async setAllowanceAsync(tokenAddress: string, ownerAddress: string, spenderAddress: string,
-                                   amountInBaseUnits: BigNumber.BigNumber): Promise<string> {
+                                   amountInBaseUnits: BigNumber, txOpts: TransactionOpts = {}): Promise<string> {
         await assert.isSenderAddressAsync('ownerAddress', ownerAddress, this._web3Wrapper);
         assert.isETHAddressHex('spenderAddress', spenderAddress);
         assert.isETHAddressHex('tokenAddress', tokenAddress);
-        assert.isBigNumber('amountInBaseUnits', amountInBaseUnits);
+        assert.isValidBaseUnitAmount('amountInBaseUnits', amountInBaseUnits);
 
         const tokenContract = await this._getTokenContractAsync(tokenAddress);
-        // Hack: for some reason default estimated gas amount causes `base fee exceeds gas limit` exception
-        // on testrpc. Probably related to https://github.com/ethereumjs/testrpc/issues/294
-        // TODO: Debug issue in testrpc and submit a PR, then remove this hack
-        const networkIdIfExists = await this._web3Wrapper.getNetworkIdIfExistsAsync();
-        const gas = networkIdIfExists === constants.TESTRPC_NETWORK_ID ? ALLOWANCE_TO_ZERO_GAS_AMOUNT : undefined;
         const txHash = await tokenContract.approve.sendTransactionAsync(spenderAddress, amountInBaseUnits, {
             from: ownerAddress,
-            gas,
+            gas: txOpts.gasLimit,
+            gasPrice: txOpts.gasPrice,
         });
         return txHash;
     }
@@ -99,12 +94,13 @@ export class TokenWrapper extends ContractWrapper {
      * @param   ownerAddress        The hex encoded user Ethereum address who would like to set an allowance
      *                              for spenderAddress.
      * @param   spenderAddress      The hex encoded user Ethereum address who will be able to spend the set allowance.
+     * @param   txOpts              Transaction parameters.
      * @return Transaction hash.
      */
     public async setUnlimitedAllowanceAsync(tokenAddress: string, ownerAddress: string,
-                                            spenderAddress: string): Promise<string> {
+                                            spenderAddress: string, txOpts: TransactionOpts = {}): Promise<string> {
         const txHash = await this.setAllowanceAsync(
-            tokenAddress, ownerAddress, spenderAddress, this.UNLIMITED_ALLOWANCE_IN_BASE_UNITS,
+            tokenAddress, ownerAddress, spenderAddress, this.UNLIMITED_ALLOWANCE_IN_BASE_UNITS, txOpts,
         );
         return txHash;
     }
@@ -117,7 +113,7 @@ export class TokenWrapper extends ContractWrapper {
      * @param   methodOpts      Optional arguments this method accepts.
      */
     public async getAllowanceAsync(tokenAddress: string, ownerAddress: string,
-                                   spenderAddress: string, methodOpts?: MethodOpts): Promise<BigNumber.BigNumber> {
+                                   spenderAddress: string, methodOpts?: MethodOpts): Promise<BigNumber> {
         assert.isETHAddressHex('ownerAddress', ownerAddress);
         assert.isETHAddressHex('tokenAddress', tokenAddress);
 
@@ -135,11 +131,11 @@ export class TokenWrapper extends ContractWrapper {
      * @param   methodOpts      Optional arguments this method accepts.
      */
     public async getProxyAllowanceAsync(tokenAddress: string, ownerAddress: string,
-                                        methodOpts?: MethodOpts): Promise<BigNumber.BigNumber> {
+                                        methodOpts?: MethodOpts): Promise<BigNumber> {
         assert.isETHAddressHex('ownerAddress', ownerAddress);
         assert.isETHAddressHex('tokenAddress', tokenAddress);
 
-        const proxyAddress = await this._getTokenTransferProxyAddressAsync();
+        const proxyAddress = this._tokenTransferProxyWrapper.getContractAddress();
         const allowanceInBaseUnits = await this.getAllowanceAsync(tokenAddress, ownerAddress, proxyAddress, methodOpts);
         return allowanceInBaseUnits;
     }
@@ -150,16 +146,19 @@ export class TokenWrapper extends ContractWrapper {
      * @param   ownerAddress        The hex encoded user Ethereum address who is setting an allowance
      *                              for the Proxy contract.
      * @param   amountInBaseUnits   The allowance amount specified in baseUnits.
+     * @param   txOpts              Transaction parameters.
      * @return Transaction hash.
      */
     public async setProxyAllowanceAsync(tokenAddress: string, ownerAddress: string,
-                                        amountInBaseUnits: BigNumber.BigNumber): Promise<string> {
+                                        amountInBaseUnits: BigNumber, txOpts: TransactionOpts = {}): Promise<string> {
         assert.isETHAddressHex('ownerAddress', ownerAddress);
         assert.isETHAddressHex('tokenAddress', tokenAddress);
-        assert.isBigNumber('amountInBaseUnits', amountInBaseUnits);
+        assert.isValidBaseUnitAmount('amountInBaseUnits', amountInBaseUnits);
 
-        const proxyAddress = await this._getTokenTransferProxyAddressAsync();
-        const txHash = await this.setAllowanceAsync(tokenAddress, ownerAddress, proxyAddress, amountInBaseUnits);
+        const proxyAddress = this._tokenTransferProxyWrapper.getContractAddress();
+        const txHash = await this.setAllowanceAsync(
+            tokenAddress, ownerAddress, proxyAddress, amountInBaseUnits, txOpts,
+        );
         return txHash;
     }
     /**
@@ -170,11 +169,14 @@ export class TokenWrapper extends ContractWrapper {
      * @param   tokenAddress        The hex encoded contract Ethereum address where the ERC20 token is deployed.
      * @param   ownerAddress        The hex encoded user Ethereum address who is setting an allowance
      *                              for the Proxy contract.
+     * @param   txOpts              Transaction parameters.
      * @return Transaction hash.
      */
-    public async setUnlimitedProxyAllowanceAsync(tokenAddress: string, ownerAddress: string): Promise<string> {
+    public async setUnlimitedProxyAllowanceAsync(
+        tokenAddress: string, ownerAddress: string, txOpts: TransactionOpts = {},
+    ): Promise<string> {
         const txHash = await this.setProxyAllowanceAsync(
-            tokenAddress, ownerAddress, this.UNLIMITED_ALLOWANCE_IN_BASE_UNITS,
+            tokenAddress, ownerAddress, this.UNLIMITED_ALLOWANCE_IN_BASE_UNITS, txOpts,
         );
         return txHash;
     }
@@ -184,14 +186,15 @@ export class TokenWrapper extends ContractWrapper {
      * @param   fromAddress         The hex encoded user Ethereum address that will send the funds.
      * @param   toAddress           The hex encoded user Ethereum address that will receive the funds.
      * @param   amountInBaseUnits   The amount (specified in baseUnits) of the token to transfer.
+     * @param   txOpts              Transaction parameters.
      * @return Transaction hash.
      */
     public async transferAsync(tokenAddress: string, fromAddress: string, toAddress: string,
-                               amountInBaseUnits: BigNumber.BigNumber): Promise<string> {
+                               amountInBaseUnits: BigNumber, txOpts: TransactionOpts = {}): Promise<string> {
         assert.isETHAddressHex('tokenAddress', tokenAddress);
         await assert.isSenderAddressAsync('fromAddress', fromAddress, this._web3Wrapper);
         assert.isETHAddressHex('toAddress', toAddress);
-        assert.isBigNumber('amountInBaseUnits', amountInBaseUnits);
+        assert.isValidBaseUnitAmount('amountInBaseUnits', amountInBaseUnits);
 
         const tokenContract = await this._getTokenContractAsync(tokenAddress);
 
@@ -202,6 +205,8 @@ export class TokenWrapper extends ContractWrapper {
 
         const txHash = await tokenContract.transfer.sendTransactionAsync(toAddress, amountInBaseUnits, {
             from: fromAddress,
+            gas: txOpts.gasLimit,
+            gasPrice: txOpts.gasPrice,
         });
         return txHash;
     }
@@ -216,16 +221,17 @@ export class TokenWrapper extends ContractWrapper {
      *                              `fromAddress` must have set an allowance to the `senderAddress`
      *                              before this call.
      * @param   amountInBaseUnits   The amount (specified in baseUnits) of the token to transfer.
+     * @param   txOpts              Transaction parameters.
      * @return Transaction hash.
      */
     public async transferFromAsync(tokenAddress: string, fromAddress: string, toAddress: string,
-                                   senderAddress: string, amountInBaseUnits: BigNumber.BigNumber):
+                                   senderAddress: string, amountInBaseUnits: BigNumber, txOpts: TransactionOpts = {}):
                                    Promise<string> {
         assert.isETHAddressHex('tokenAddress', tokenAddress);
         assert.isETHAddressHex('fromAddress', fromAddress);
         assert.isETHAddressHex('toAddress', toAddress);
         await assert.isSenderAddressAsync('senderAddress', senderAddress, this._web3Wrapper);
-        assert.isBigNumber('amountInBaseUnits', amountInBaseUnits);
+        assert.isValidBaseUnitAmount('amountInBaseUnits', amountInBaseUnits);
 
         const tokenContract = await this._getTokenContractAsync(tokenAddress);
 
@@ -243,6 +249,8 @@ export class TokenWrapper extends ContractWrapper {
             fromAddress, toAddress, amountInBaseUnits,
             {
                 from: senderAddress,
+                gas: txOpts.gasLimit,
+                gasPrice: txOpts.gasPrice,
             },
         );
         return txHash;
@@ -251,34 +259,29 @@ export class TokenWrapper extends ContractWrapper {
      * Subscribe to an event type emitted by the Token contract.
      * @param   tokenAddress        The hex encoded address where the ERC20 token is deployed.
      * @param   eventName           The token contract event you would like to subscribe to.
-     * @param   subscriptionOpts    Subscriptions options that let you configure the subscription.
      * @param   indexFilterValues   An object where the keys are indexed args returned by the event and
      *                              the value is the value you are interested in. E.g `{maker: aUserAddressHex}`
-     * @return ContractEventEmitter object
+     * @param   callback            Callback that gets called when a log is added/removed
+     * @return Subscription token used later to unsubscribe
      */
-    public async subscribeAsync(tokenAddress: string, eventName: TokenEvents, subscriptionOpts: SubscriptionOpts,
-                                indexFilterValues: IndexedFilterValues): Promise<ContractEventEmitter> {
+    public subscribe<ArgsType extends TokenContractEventArgs>(
+        tokenAddress: string, eventName: TokenEvents, indexFilterValues: IndexedFilterValues,
+        callback: EventCallback<ArgsType>): string {
         assert.isETHAddressHex('tokenAddress', tokenAddress);
         assert.doesBelongToStringEnum('eventName', eventName, TokenEvents);
-        assert.doesConformToSchema('subscriptionOpts', subscriptionOpts, schemas.subscriptionOptsSchema);
         assert.doesConformToSchema('indexFilterValues', indexFilterValues, schemas.indexFilterValuesSchema);
-        const tokenContract = await this._getTokenContractAsync(tokenAddress);
-        let createLogEvent: CreateContractEvent;
-        switch (eventName) {
-            case TokenEvents.Approval:
-                createLogEvent = tokenContract.Approval;
-                break;
-            case TokenEvents.Transfer:
-                createLogEvent = tokenContract.Transfer;
-                break;
-            default:
-                throw utils.spawnSwitchErr('TokenEvents', eventName);
-        }
-
-        const logEventObj: ContractEventObj = createLogEvent(indexFilterValues, subscriptionOpts);
-        const eventEmitter = eventUtils.wrapEventEmitter(logEventObj);
-        this._tokenLogEventEmitters.push(eventEmitter);
-        return eventEmitter;
+        assert.isFunction('callback', callback);
+        const subscriptionToken = this._subscribe<ArgsType>(
+            tokenAddress, eventName, indexFilterValues, artifacts.TokenArtifact.abi, callback,
+        );
+        return subscriptionToken;
+    }
+    /**
+     * Cancel a subscription
+     * @param   subscriptionToken Subscription token returned by `subscribe()`
+     */
+    public unsubscribe(subscriptionToken: string): void {
+        this._unsubscribe(subscriptionToken);
     }
     /**
      * Gets historical logs without creating a subscription
@@ -289,28 +292,20 @@ export class TokenWrapper extends ContractWrapper {
      *                              the value is the value you are interested in. E.g `{_from: aUserAddressHex}`
      * @return  Array of logs that match the parameters
      */
-    public async getLogsAsync(tokenAddress: string, eventName: TokenEvents, subscriptionOpts: SubscriptionOpts,
-                              indexFilterValues: IndexedFilterValues): Promise<LogWithDecodedArgs[]> {
+    public async getLogsAsync<ArgsType extends TokenContractEventArgs>(
+        tokenAddress: string, eventName: TokenEvents, subscriptionOpts: SubscriptionOpts,
+        indexFilterValues: IndexedFilterValues): Promise<Array<LogWithDecodedArgs<ArgsType>>> {
         assert.isETHAddressHex('tokenAddress', tokenAddress);
         assert.doesBelongToStringEnum('eventName', eventName, TokenEvents);
         assert.doesConformToSchema('subscriptionOpts', subscriptionOpts, schemas.subscriptionOptsSchema);
         assert.doesConformToSchema('indexFilterValues', indexFilterValues, schemas.indexFilterValuesSchema);
-        const logs = await this._getLogsAsync(
+        const logs = await this._getLogsAsync<ArgsType>(
             tokenAddress, eventName, subscriptionOpts, indexFilterValues, artifacts.TokenArtifact.abi,
         );
         return logs;
     }
-    /**
-     * Stops watching for all token events
-     */
-    public async stopWatchingAllEventsAsync(): Promise<void> {
-        const stopWatchingPromises = _.map(this._tokenLogEventEmitters,
-                                           logEventObj => logEventObj.stopWatchingAsync());
-        await Promise.all(stopWatchingPromises);
-        this._tokenLogEventEmitters = [];
-    }
-    private async _invalidateContractInstancesAsync(): Promise<void> {
-        await this.stopWatchingAllEventsAsync();
+    private _invalidateContractInstances(): void {
+        this.unsubscribeAll();
         this._tokenContractsByAddress = {};
     }
     private async _getTokenContractAsync(tokenAddress: string): Promise<TokenContract> {
@@ -321,12 +316,8 @@ export class TokenWrapper extends ContractWrapper {
         const contractInstance = await this._instantiateContractIfExistsAsync<TokenContract>(
             artifacts.TokenArtifact, tokenAddress,
         );
-        tokenContract = contractInstance as TokenContract;
+        tokenContract = contractInstance;
         this._tokenContractsByAddress[tokenAddress] = tokenContract;
         return tokenContract;
     }
-    private async _getTokenTransferProxyAddressAsync(): Promise<string> {
-        const tokenTransferProxyContractAddress = await this._tokenTransferProxyContractAddressFetcher();
-        return tokenTransferProxyContractAddress;
-    }
 }

packages/0x.js/src/globals.d.ts

@@ -12,12 +12,6 @@ declare module 'web3-provider-engine/subproviders/rpc';
 // disallow `namespace`, we disable tslint for the following.
 /* tslint:disable */
 declare namespace Chai {
-    interface NumberComparer {
-        (value: number|BigNumber.BigNumber, message?: string): Assertion;
-    }
-    interface NumericComparison {
-        greaterThan: NumberComparer;
-    }
     interface Assertion {
         bignumber: Assertion;
         // HACK: In order to comply with chai-as-promised we make eventually a `PromisedAssertion` not an `Assertion`
@@ -70,8 +64,6 @@ declare module 'truffle-hdwallet-provider' {
 
 // abi-decoder declarations
 interface DecodedLogArg {
-    name: string;
-    value: string|BigNumber.BigNumber;
 }
 interface DecodedLog {
     name: string;

packages/0x.js/src/globalsAugment.d.ts

@@ -0,0 +1,23 @@
+import BigNumber from 'bignumber.js';
+
+// HACK: This module overrides the Chai namespace so that we can use BigNumber types inside.
+// Source: https://github.com/Microsoft/TypeScript/issues/7352#issuecomment-191547232
+declare global {
+    // HACK: In order to merge the bignumber declaration added by chai-bignumber to the chai Assertion
+    // interface we must use `namespace` as the Chai definitelyTyped definition does. Since we otherwise
+    // disallow `namespace`, we disable tslint for the following.
+    /* tslint:disable */
+    namespace Chai {
+        interface NumberComparer {
+            (value: number|BigNumber, message?: string): Assertion;
+        }
+        interface NumericComparison {
+            greaterThan: NumberComparer;
+        }
+    }
+    /* tslint:enable */
+    interface DecodedLogArg {
+        name: string;
+        value: string|BigNumber;
+    }
+}

packages/0x.js/src/index.ts

@@ -6,8 +6,6 @@ export {
     ECSignature,
     ZeroExError,
     EventCallback,
-    EventCallbackAsync,
-    EventCallbackSync,
     ExchangeContractErrs,
     ContractEvent,
     Token,
@@ -16,10 +14,8 @@ export {
     IndexedFilterValues,
     SubscriptionOpts,
     BlockParam,
-    OrderFillOrKillRequest,
     OrderCancellationRequest,
     OrderFillRequest,
-    ContractEventEmitter,
     LogErrorContractEventArgs,
     LogCancelContractEventArgs,
     LogFillContractEventArgs,
@@ -28,12 +24,20 @@ export {
     ApprovalContractEventArgs,
     TokenContractEventArgs,
     ContractEventArgs,
+    ContractEventArg,
     Web3Provider,
     ZeroExConfig,
+    TransactionReceipt,
     TransactionReceiptWithDecodedLogs,
     LogWithDecodedArgs,
-    DecodedLogArgs,
     MethodOpts,
     OrderTransactionOpts,
     FilterObject,
+    LogEvent,
+    DecodedLogEvent,
+    EventWatcherCallback,
+    OnOrderStateChangeCallback,
+    OrderStateValid,
+    OrderStateInvalid,
+    OrderState,
 } from './types';

packages/0x.js/src/order_watcher/event_watcher.ts

@@ -0,0 +1,89 @@
+import * as _ from 'lodash';
+import * as Web3 from 'web3';
+
+import {
+    BlockParamLiteral,
+    EventCallback,
+    EventWatcherCallback,
+    ZeroExError,
+} from '../types';
+import {AbiDecoder} from '../utils/abi_decoder';
+import {assert} from '../utils/assert';
+import {intervalUtils} from '../utils/interval_utils';
+import {utils} from '../utils/utils';
+import {Web3Wrapper} from '../web3_wrapper';
+
+const DEFAULT_EVENT_POLLING_INTERVAL_MS = 200;
+
+enum LogEventState {
+    Removed,
+    Added,
+}
+
+/*
+ * The EventWatcher watches for blockchain events at the specified block confirmation
+ * depth.
+ */
+export class EventWatcher {
+    private _web3Wrapper: Web3Wrapper;
+    private _pollingIntervalMs: number;
+    private _intervalIdIfExists?: NodeJS.Timer;
+    private _lastEvents: Web3.LogEntry[] = [];
+    constructor(web3Wrapper: Web3Wrapper, pollingIntervalIfExistsMs: undefined|number) {
+        this._web3Wrapper = web3Wrapper;
+        this._pollingIntervalMs = _.isUndefined(pollingIntervalIfExistsMs) ?
+                                    DEFAULT_EVENT_POLLING_INTERVAL_MS :
+                                    pollingIntervalIfExistsMs;
+    }
+    public subscribe(callback: EventWatcherCallback): void {
+        assert.isFunction('callback', callback);
+        if (!_.isUndefined(this._intervalIdIfExists)) {
+            throw new Error(ZeroExError.SubscriptionAlreadyPresent);
+        }
+        this._intervalIdIfExists = intervalUtils.setAsyncExcludingInterval(
+            this._pollForBlockchainEventsAsync.bind(this, callback), this._pollingIntervalMs,
+        );
+    }
+    public unsubscribe(): void {
+        this._lastEvents = [];
+        if (!_.isUndefined(this._intervalIdIfExists)) {
+            intervalUtils.clearAsyncExcludingInterval(this._intervalIdIfExists);
+            delete this._intervalIdIfExists;
+        }
+    }
+    private async _pollForBlockchainEventsAsync(callback: EventWatcherCallback): Promise<void> {
+        const pendingEvents = await this._getEventsAsync();
+        if (pendingEvents.length === 0) {
+            // HACK: Sometimes when node rebuilds the pending block we get back the empty result.
+            // We don't want to emit a lot of removal events and bring them back after a couple of miliseconds,
+            // that's why we just ignore those cases.
+            return;
+        }
+        const removedEvents = _.differenceBy(this._lastEvents, pendingEvents, JSON.stringify);
+        const newEvents = _.differenceBy(pendingEvents, this._lastEvents, JSON.stringify);
+        await this._emitDifferencesAsync(removedEvents, LogEventState.Removed, callback);
+        await this._emitDifferencesAsync(newEvents, LogEventState.Added, callback);
+        this._lastEvents = pendingEvents;
+    }
+    private async _getEventsAsync(): Promise<Web3.LogEntry[]> {
+        const eventFilter = {
+            fromBlock: BlockParamLiteral.Pending,
+            toBlock: BlockParamLiteral.Pending,
+        };
+        const events = await this._web3Wrapper.getLogsAsync(eventFilter);
+        return events;
+    }
+    private async _emitDifferencesAsync(
+        logs: Web3.LogEntry[], logEventState: LogEventState, callback: EventWatcherCallback,
+    ): Promise<void> {
+        for (const log of logs) {
+            const logEvent = {
+                removed: logEventState === LogEventState.Removed,
+                ...log,
+            };
+            if (!_.isUndefined(this._intervalIdIfExists)) {
+                callback(logEvent);
+            }
+        }
+    }
+}

packages/0x.js/src/order_watcher/expiration_watcher.ts

@@ -0,0 +1,77 @@
+import {BigNumber} from 'bignumber.js';
+import {RBTree} from 'bintrees';
+import * as _ from 'lodash';
+
+import {ZeroEx} from '../0x';
+import {SignedOrder, ZeroExError} from '../types';
+import {intervalUtils} from '../utils/interval_utils';
+import {utils} from '../utils/utils';
+
+const DEFAULT_EXPIRATION_MARGIN_MS = 0;
+const DEFAULT_ORDER_EXPIRATION_CHECKING_INTERVAL_MS = 50;
+
+/**
+ * This class includes the functionality to detect expired orders.
+ * It stores them in a min heap by expiration time and checks for expired ones every `orderExpirationCheckingIntervalMs`
+ */
+export class ExpirationWatcher {
+    private orderHashByExpirationRBTree: RBTree<string>;
+    private expiration: {[orderHash: string]: BigNumber} = {};
+    private orderExpirationCheckingIntervalMs: number;
+    private expirationMarginMs: number;
+    private orderExpirationCheckingIntervalIdIfExists?: NodeJS.Timer;
+    constructor(expirationMarginIfExistsMs?: number,
+                orderExpirationCheckingIntervalIfExistsMs?: number) {
+        this.expirationMarginMs = expirationMarginIfExistsMs ||
+                                  DEFAULT_EXPIRATION_MARGIN_MS;
+        this.orderExpirationCheckingIntervalMs = expirationMarginIfExistsMs ||
+                                                 DEFAULT_ORDER_EXPIRATION_CHECKING_INTERVAL_MS;
+        const scoreFunction = (orderHash: string) => this.expiration[orderHash].toNumber();
+        const comparator = (lhs: string, rhs: string) => scoreFunction(lhs) - scoreFunction(rhs);
+        this.orderHashByExpirationRBTree = new RBTree(comparator);
+    }
+    public subscribe(callback: (orderHash: string) => void): void {
+        if (!_.isUndefined(this.orderExpirationCheckingIntervalIdIfExists)) {
+            throw new Error(ZeroExError.SubscriptionAlreadyPresent);
+        }
+        this.orderExpirationCheckingIntervalIdIfExists = intervalUtils.setAsyncExcludingInterval(
+            this.pruneExpiredOrders.bind(this, callback), this.orderExpirationCheckingIntervalMs,
+        );
+    }
+    public unsubscribe(): void {
+        if (_.isUndefined(this.orderExpirationCheckingIntervalIdIfExists)) {
+            throw new Error(ZeroExError.SubscriptionNotFound);
+        }
+        intervalUtils.clearAsyncExcludingInterval(this.orderExpirationCheckingIntervalIdIfExists);
+        delete this.orderExpirationCheckingIntervalIdIfExists;
+    }
+    public addOrder(orderHash: string, expirationUnixTimestampMs: BigNumber): void {
+        this.expiration[orderHash] = expirationUnixTimestampMs;
+        this.orderHashByExpirationRBTree.insert(orderHash);
+    }
+    public removeOrder(orderHash: string): void {
+        this.orderHashByExpirationRBTree.remove(orderHash);
+        delete this.expiration[orderHash];
+    }
+    private pruneExpiredOrders(callback: (orderHash: string) => void): void {
+        const currentUnixTimestampMs = utils.getCurrentUnixTimestampMs();
+        while (true) {
+            const hasTrakedOrders = this.orderHashByExpirationRBTree.size === 0;
+            if (hasTrakedOrders) {
+                break;
+            }
+            const nextOrderHashToExpire = this.orderHashByExpirationRBTree.min();
+            const hasNoExpiredOrders = this.expiration[nextOrderHashToExpire].greaterThan(
+                currentUnixTimestampMs.plus(this.expirationMarginMs),
+            );
+            const isSubscriptionActive = _.isUndefined(this.orderExpirationCheckingIntervalIdIfExists);
+            if (hasNoExpiredOrders || isSubscriptionActive) {
+                break;
+            }
+            const orderHash = this.orderHashByExpirationRBTree.min();
+            this.orderHashByExpirationRBTree.remove(orderHash);
+            delete this.expiration[orderHash];
+            callback(orderHash);
+        }
+    }
+}

packages/0x.js/src/order_watcher/order_state_watcher.ts

@@ -0,0 +1,327 @@
+import {schemas} from '@0xproject/json-schemas';
+import * as _ from 'lodash';
+
+import {ZeroEx} from '../0x';
+import {artifacts} from '../artifacts';
+import {ExchangeWrapper} from '../contract_wrappers/exchange_wrapper';
+import {TokenWrapper} from '../contract_wrappers/token_wrapper';
+import {BalanceAndProxyAllowanceLazyStore} from '../stores/balance_proxy_allowance_lazy_store';
+import {OrderFilledCancelledLazyStore} from '../stores/order_filled_cancelled_lazy_store';
+import {
+    ApprovalContractEventArgs,
+    BlockParamLiteral,
+    ContractEventArgs,
+    ExchangeContractErrs,
+    ExchangeEvents,
+    LogCancelContractEventArgs,
+    LogEvent,
+    LogFillContractEventArgs,
+    LogWithDecodedArgs,
+    OnOrderStateChangeCallback,
+    OrderState,
+    OrderStateWatcherConfig,
+    SignedOrder,
+    TokenEvents,
+    TransferContractEventArgs,
+    Web3Provider,
+    ZeroExError,
+} from '../types';
+import {AbiDecoder} from '../utils/abi_decoder';
+import {assert} from '../utils/assert';
+import {intervalUtils} from '../utils/interval_utils';
+import {OrderStateUtils} from '../utils/order_state_utils';
+import {utils} from '../utils/utils';
+import {Web3Wrapper} from '../web3_wrapper';
+
+import {EventWatcher} from './event_watcher';
+import {ExpirationWatcher} from './expiration_watcher';
+
+interface DependentOrderHashes {
+    [makerAddress: string]: {
+        [makerToken: string]: Set<string>;
+    };
+}
+
+interface OrderByOrderHash {
+    [orderHash: string]: SignedOrder;
+}
+
+interface OrderStateByOrderHash {
+    [orderHash: string]: OrderState;
+}
+
+const DEFAULT_CLEANUP_JOB_INTERVAL_MS = 1000 * 60 * 60; // 1h
+
+/**
+ * This class includes all the functionality related to watching a set of orders
+ * for potential changes in order validity/fillability. The orderWatcher notifies
+ * the subscriber of these changes so that a final decison can be made on whether
+ * the order should be deemed invalid.
+ */
+export class OrderStateWatcher {
+    private _orderStateByOrderHashCache: OrderStateByOrderHash = {};
+    private _orderByOrderHash: OrderByOrderHash = {};
+    private _dependentOrderHashes: DependentOrderHashes = {};
+    private _callbackIfExists?: OnOrderStateChangeCallback;
+    private _eventWatcher: EventWatcher;
+    private _web3Wrapper: Web3Wrapper;
+    private _abiDecoder: AbiDecoder;
+    private _expirationWatcher: ExpirationWatcher;
+    private _orderStateUtils: OrderStateUtils;
+    private _orderFilledCancelledLazyStore: OrderFilledCancelledLazyStore;
+    private _balanceAndProxyAllowanceLazyStore: BalanceAndProxyAllowanceLazyStore;
+    private _cleanupJobInterval: number;
+    private _cleanupJobIntervalIdIfExists?: NodeJS.Timer;
+    constructor(
+        web3Wrapper: Web3Wrapper, abiDecoder: AbiDecoder, token: TokenWrapper, exchange: ExchangeWrapper,
+        config?: OrderStateWatcherConfig,
+    ) {
+        this._abiDecoder = abiDecoder;
+        this._web3Wrapper = web3Wrapper;
+        const pollingIntervalIfExistsMs = _.isUndefined(config) ? undefined : config.eventPollingIntervalMs;
+        this._eventWatcher = new EventWatcher(web3Wrapper, pollingIntervalIfExistsMs);
+        this._balanceAndProxyAllowanceLazyStore = new BalanceAndProxyAllowanceLazyStore(
+            token, BlockParamLiteral.Pending,
+        );
+        this._orderFilledCancelledLazyStore = new OrderFilledCancelledLazyStore(exchange);
+        this._orderStateUtils = new OrderStateUtils(
+            this._balanceAndProxyAllowanceLazyStore, this._orderFilledCancelledLazyStore,
+        );
+        const orderExpirationCheckingIntervalMsIfExists = _.isUndefined(config) ?
+                                                          undefined :
+                                                          config.orderExpirationCheckingIntervalMs;
+        const expirationMarginIfExistsMs = _.isUndefined(config) ?
+                                           undefined :
+                                           config.expirationMarginMs;
+        this._expirationWatcher = new ExpirationWatcher(
+            expirationMarginIfExistsMs, orderExpirationCheckingIntervalMsIfExists,
+        );
+        this._cleanupJobInterval = _.isUndefined(config) || _.isUndefined(config.cleanupJobIntervalMs) ?
+                                   DEFAULT_CLEANUP_JOB_INTERVAL_MS :
+                                   config.cleanupJobIntervalMs;
+    }
+    /**
+     * Add an order to the orderStateWatcher. Before the order is added, it's
+     * signature is verified.
+     * @param   signedOrder     The order you wish to start watching.
+     */
+    public addOrder(signedOrder: SignedOrder): void {
+        assert.doesConformToSchema('signedOrder', signedOrder, schemas.signedOrderSchema);
+        const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+        assert.isValidSignature(orderHash, signedOrder.ecSignature, signedOrder.maker);
+        this._orderByOrderHash[orderHash] = signedOrder;
+        this.addToDependentOrderHashes(signedOrder, orderHash);
+        const expirationUnixTimestampMs = signedOrder.expirationUnixTimestampSec.times(1000);
+        this._expirationWatcher.addOrder(orderHash, expirationUnixTimestampMs);
+    }
+    /**
+     * Removes an order from the orderStateWatcher
+     * @param   orderHash     The orderHash of the order you wish to stop watching.
+     */
+    public removeOrder(orderHash: string): void {
+        assert.doesConformToSchema('orderHash', orderHash, schemas.orderHashSchema);
+        const signedOrder = this._orderByOrderHash[orderHash];
+        if (_.isUndefined(signedOrder)) {
+            return; // noop
+        }
+        delete this._orderByOrderHash[orderHash];
+        delete this._orderStateByOrderHashCache[orderHash];
+        const exchange = (this._orderFilledCancelledLazyStore as any).exchange as ExchangeWrapper;
+        const zrxTokenAddress = exchange.getZRXTokenAddress();
+        this.removeFromDependentOrderHashes(signedOrder.maker, zrxTokenAddress, orderHash);
+        this.removeFromDependentOrderHashes(signedOrder.maker, signedOrder.makerTokenAddress, orderHash);
+        this._expirationWatcher.removeOrder(orderHash);
+    }
+    /**
+     * Starts an orderStateWatcher subscription. The callback will be called every time a watched order's
+     * backing blockchain state has changed. This is a call-to-action for the caller to re-validate the order.
+     * @param   callback            Receives the orderHash of the order that should be re-validated, together
+     *                              with all the order-relevant blockchain state needed to re-validate the order.
+     */
+    public subscribe(callback: OnOrderStateChangeCallback): void {
+        assert.isFunction('callback', callback);
+        if (!_.isUndefined(this._callbackIfExists)) {
+            throw new Error(ZeroExError.SubscriptionAlreadyPresent);
+        }
+        this._callbackIfExists = callback;
+        this._eventWatcher.subscribe(this._onEventWatcherCallbackAsync.bind(this));
+        this._expirationWatcher.subscribe(this._onOrderExpired.bind(this));
+        this._cleanupJobIntervalIdIfExists = intervalUtils.setAsyncExcludingInterval(
+            this._cleanupAsync.bind(this), this._cleanupJobInterval,
+        );
+    }
+    /**
+     * Ends an orderStateWatcher subscription.
+     */
+    public unsubscribe(): void {
+        if (_.isUndefined(this._callbackIfExists) || _.isUndefined(this._cleanupJobIntervalIdIfExists)) {
+            throw new Error(ZeroExError.SubscriptionNotFound);
+        }
+        this._balanceAndProxyAllowanceLazyStore.deleteAll();
+        this._orderFilledCancelledLazyStore.deleteAll();
+        delete this._callbackIfExists;
+        this._eventWatcher.unsubscribe();
+        this._expirationWatcher.unsubscribe();
+        intervalUtils.clearAsyncExcludingInterval(this._cleanupJobIntervalIdIfExists);
+    }
+    private async _cleanupAsync(): Promise<void> {
+        for (const orderHash of _.keys(this._orderByOrderHash)) {
+            this._cleanupOrderRelatedState(orderHash);
+            await this._emitRevalidateOrdersAsync([orderHash]);
+        }
+    }
+    private _cleanupOrderRelatedState(orderHash: string): void {
+        const signedOrder = this._orderByOrderHash[orderHash];
+
+        this._orderFilledCancelledLazyStore.deleteFilledTakerAmount(orderHash);
+        this._orderFilledCancelledLazyStore.deleteCancelledTakerAmount(orderHash);
+
+        this._balanceAndProxyAllowanceLazyStore.deleteBalance(signedOrder.makerTokenAddress, signedOrder.maker);
+        this._balanceAndProxyAllowanceLazyStore.deleteProxyAllowance(signedOrder.makerTokenAddress, signedOrder.maker);
+        this._balanceAndProxyAllowanceLazyStore.deleteBalance(signedOrder.takerTokenAddress, signedOrder.taker);
+        this._balanceAndProxyAllowanceLazyStore.deleteProxyAllowance(signedOrder.takerTokenAddress, signedOrder.taker);
+
+        const zrxTokenAddress = this._getZRXTokenAddress();
+        if (!signedOrder.makerFee.isZero()) {
+            this._balanceAndProxyAllowanceLazyStore.deleteBalance(zrxTokenAddress, signedOrder.maker);
+            this._balanceAndProxyAllowanceLazyStore.deleteProxyAllowance(zrxTokenAddress, signedOrder.maker);
+        }
+        if (!signedOrder.takerFee.isZero()) {
+            this._balanceAndProxyAllowanceLazyStore.deleteBalance(zrxTokenAddress, signedOrder.taker);
+            this._balanceAndProxyAllowanceLazyStore.deleteProxyAllowance(zrxTokenAddress, signedOrder.taker);
+        }
+    }
+    private _onOrderExpired(orderHash: string): void {
+        const orderState: OrderState = {
+            isValid: false,
+            orderHash,
+            error: ExchangeContractErrs.OrderFillExpired,
+        };
+        if (!_.isUndefined(this._orderByOrderHash[orderHash])) {
+            this.removeOrder(orderHash);
+            if (!_.isUndefined(this._callbackIfExists)) {
+                this._callbackIfExists(orderState);
+            }
+        }
+    }
+    private async _onEventWatcherCallbackAsync(log: LogEvent): Promise<void> {
+        const maybeDecodedLog = this._abiDecoder.tryToDecodeLogOrNoop(log);
+        const isLogDecoded = !_.isUndefined((maybeDecodedLog as LogWithDecodedArgs<any>).event);
+        if (!isLogDecoded) {
+            return; // noop
+        }
+        const decodedLog = maybeDecodedLog as LogWithDecodedArgs<ContractEventArgs>;
+        let makerToken: string;
+        let makerAddress: string;
+        switch (decodedLog.event) {
+            case TokenEvents.Approval:
+            {
+                // Invalidate cache
+                const args = decodedLog.args as ApprovalContractEventArgs;
+                this._balanceAndProxyAllowanceLazyStore.deleteProxyAllowance(decodedLog.address, args._owner);
+                // Revalidate orders
+                makerToken = decodedLog.address;
+                makerAddress = args._owner;
+                if (!_.isUndefined(this._dependentOrderHashes[makerAddress]) &&
+                    !_.isUndefined(this._dependentOrderHashes[makerAddress][makerToken])) {
+                    const orderHashes = Array.from(this._dependentOrderHashes[makerAddress][makerToken]);
+                    await this._emitRevalidateOrdersAsync(orderHashes);
+                }
+                break;
+            }
+            case TokenEvents.Transfer:
+            {
+                // Invalidate cache
+                const args = decodedLog.args as TransferContractEventArgs;
+                this._balanceAndProxyAllowanceLazyStore.deleteBalance(decodedLog.address, args._from);
+                this._balanceAndProxyAllowanceLazyStore.deleteBalance(decodedLog.address, args._to);
+                // Revalidate orders
+                makerToken = decodedLog.address;
+                makerAddress = args._from;
+                if (!_.isUndefined(this._dependentOrderHashes[makerAddress]) &&
+                    !_.isUndefined(this._dependentOrderHashes[makerAddress][makerToken])) {
+                    const orderHashes = Array.from(this._dependentOrderHashes[makerAddress][makerToken]);
+                    await this._emitRevalidateOrdersAsync(orderHashes);
+                }
+                break;
+            }
+            case ExchangeEvents.LogFill:
+            {
+                // Invalidate cache
+                const args = decodedLog.args as LogFillContractEventArgs;
+                this._orderFilledCancelledLazyStore.deleteFilledTakerAmount(args.orderHash);
+                // Revalidate orders
+                const orderHash = args.orderHash;
+                const isOrderWatched = !_.isUndefined(this._orderByOrderHash[orderHash]);
+                if (isOrderWatched) {
+                    await this._emitRevalidateOrdersAsync([orderHash]);
+                }
+                break;
+            }
+            case ExchangeEvents.LogCancel:
+            {
+                // Invalidate cache
+                const args = decodedLog.args as LogCancelContractEventArgs;
+                this._orderFilledCancelledLazyStore.deleteCancelledTakerAmount(args.orderHash);
+                // Revalidate orders
+                const orderHash = args.orderHash;
+                const isOrderWatched = !_.isUndefined(this._orderByOrderHash[orderHash]);
+                if (isOrderWatched) {
+                    await this._emitRevalidateOrdersAsync([orderHash]);
+                }
+                break;
+            }
+            case ExchangeEvents.LogError:
+                return; // noop
+
+            default:
+                throw utils.spawnSwitchErr('decodedLog.event', decodedLog.event);
+        }
+    }
+    private async _emitRevalidateOrdersAsync(orderHashes: string[]): Promise<void> {
+        for (const orderHash of orderHashes) {
+            const signedOrder = this._orderByOrderHash[orderHash];
+            // Most of these calls will never reach the network because the data is fetched from stores
+            // and only updated when cache is invalidated
+            const orderState = await this._orderStateUtils.getOrderStateAsync(signedOrder);
+            if (_.isUndefined(this._callbackIfExists)) {
+                break; // Unsubscribe was called
+            }
+            if (_.isEqual(orderState, this._orderStateByOrderHashCache[orderHash])) {
+                // Actual order state didn't change
+                continue;
+            } else {
+                this._orderStateByOrderHashCache[orderHash] = orderState;
+            }
+            this._callbackIfExists(orderState);
+        }
+    }
+    private addToDependentOrderHashes(signedOrder: SignedOrder, orderHash: string): void {
+        if (_.isUndefined(this._dependentOrderHashes[signedOrder.maker])) {
+            this._dependentOrderHashes[signedOrder.maker] = {};
+        }
+        if (_.isUndefined(this._dependentOrderHashes[signedOrder.maker][signedOrder.makerTokenAddress])) {
+            this._dependentOrderHashes[signedOrder.maker][signedOrder.makerTokenAddress] = new Set();
+        }
+        this._dependentOrderHashes[signedOrder.maker][signedOrder.makerTokenAddress].add(orderHash);
+        const zrxTokenAddress = this._getZRXTokenAddress();
+        if (_.isUndefined(this._dependentOrderHashes[signedOrder.maker][zrxTokenAddress])) {
+            this._dependentOrderHashes[signedOrder.maker][zrxTokenAddress] = new Set();
+        }
+        this._dependentOrderHashes[signedOrder.maker][zrxTokenAddress].add(orderHash);
+    }
+    private removeFromDependentOrderHashes(makerAddress: string, tokenAddress: string, orderHash: string) {
+        this._dependentOrderHashes[makerAddress][tokenAddress].delete(orderHash);
+        if (this._dependentOrderHashes[makerAddress][tokenAddress].size === 0) {
+            delete this._dependentOrderHashes[makerAddress][tokenAddress];
+        }
+        if (_.isEmpty(this._dependentOrderHashes[makerAddress])) {
+            delete this._dependentOrderHashes[makerAddress];
+        }
+    }
+    private _getZRXTokenAddress(): string {
+        const exchange = (this._orderFilledCancelledLazyStore as any).exchange as ExchangeWrapper;
+        const zrxTokenAddress = exchange.getZRXTokenAddress();
+        return zrxTokenAddress;
+    }
+}

packages/0x.js/src/order_watcher/remaining_fillable_calculator.ts

@@ -0,0 +1,87 @@
+import {BigNumber} from 'bignumber.js';
+
+import {SignedOrder} from '../types';
+
+export class RemainingFillableCalculator {
+    private signedOrder: SignedOrder;
+    private isMakerTokenZRX: boolean;
+    // Transferrable Amount is the minimum of Approval and Balance
+    private transferrableMakerTokenAmount: BigNumber;
+    private transferrableMakerFeeTokenAmount: BigNumber;
+    private remainingMakerTokenAmount: BigNumber;
+    private remainingMakerFeeAmount: BigNumber;
+    constructor(signedOrder: SignedOrder,
+                isMakerTokenZRX: boolean,
+                transferrableMakerTokenAmount: BigNumber,
+                transferrableMakerFeeTokenAmount: BigNumber,
+                remainingMakerTokenAmount: BigNumber) {
+        this.signedOrder = signedOrder;
+        this.isMakerTokenZRX = isMakerTokenZRX;
+        this.transferrableMakerTokenAmount = transferrableMakerTokenAmount;
+        this.transferrableMakerFeeTokenAmount = transferrableMakerFeeTokenAmount;
+        this.remainingMakerTokenAmount = remainingMakerTokenAmount;
+        this.remainingMakerFeeAmount = remainingMakerTokenAmount.times(signedOrder.makerFee)
+                                                                .dividedToIntegerBy(signedOrder.makerTokenAmount);
+    }
+    public computeRemainingMakerFillable(): BigNumber {
+        if (this.hasSufficientFundsForFeeAndTransferAmount()) {
+            return this.remainingMakerTokenAmount;
+        }
+        if (this.signedOrder.makerFee.isZero()) {
+            return BigNumber.min(this.remainingMakerTokenAmount, this.transferrableMakerTokenAmount);
+        }
+        return this.calculatePartiallyFillableMakerTokenAmount();
+    }
+    public computeRemainingTakerFillable(): BigNumber {
+        return this.computeRemainingMakerFillable().times(this.signedOrder.takerTokenAmount)
+                                                   .dividedToIntegerBy(this.signedOrder.makerTokenAmount);
+    }
+    private hasSufficientFundsForFeeAndTransferAmount(): boolean {
+        if (this.isMakerTokenZRX) {
+            const totalZRXTransferAmountRequired = this.remainingMakerTokenAmount.plus(this.remainingMakerFeeAmount);
+            const hasSufficientFunds = this.transferrableMakerTokenAmount.greaterThanOrEqualTo(
+                                                                            totalZRXTransferAmountRequired);
+            return hasSufficientFunds;
+        } else {
+            const hasSufficientFundsForTransferAmount = this.transferrableMakerTokenAmount.greaterThanOrEqualTo(
+                                                            this.remainingMakerTokenAmount);
+            const hasSufficientFundsForFeeAmount = this.transferrableMakerFeeTokenAmount.greaterThanOrEqualTo(
+                                                       this.remainingMakerFeeAmount);
+            const hasSufficientFunds = hasSufficientFundsForTransferAmount && hasSufficientFundsForFeeAmount;
+            return hasSufficientFunds;
+        }
+    }
+    private calculatePartiallyFillableMakerTokenAmount(): BigNumber {
+        // Given an order for 200 wei for 2 ZRXwei fee, find 100 wei for 1 ZRXwei. Order ratio is then 100:1
+        const orderToFeeRatio = this.signedOrder.makerTokenAmount.dividedBy(this.signedOrder.makerFee);
+        // The number of times the maker can fill the order, if each fill only required the transfer of a single
+        // baseUnit of fee tokens.
+        // Given 2 ZRXwei, the maximum amount of times Maker can fill this order, in terms of fees, is 2
+        const fillableTimesInFeeTokenBaseUnits = BigNumber.min(this.transferrableMakerFeeTokenAmount,
+                                                               this.remainingMakerFeeAmount);
+        // The number of times the Maker can fill the order, given the Maker Token Balance
+        // Assuming a balance of 150 wei, and an orderToFeeRatio of 100:1, maker can fill this order 1 time.
+        let fillableTimesInMakerTokenUnits = this.transferrableMakerTokenAmount.dividedBy(orderToFeeRatio);
+        if (this.isMakerTokenZRX) {
+            // If ZRX is the maker token, the Fee and the Maker amount need to be removed from the same pool;
+            // 200 ZRXwei for 2ZRXwei fee can only be filled once (need 202 ZRXwei)
+            const totalZRXTokenPooled = this.transferrableMakerTokenAmount;
+            // The purchasing power here is less as the tokens are taken from the same Pool
+            // For every one number of fills, we have to take an extra ZRX out of the pool
+            fillableTimesInMakerTokenUnits = totalZRXTokenPooled.dividedBy(
+                                                                     orderToFeeRatio.plus(new BigNumber(1)));
+
+        }
+        // When Ratio is not fully divisible there can be remainders which cannot be represented, so they are floored.
+        // This can result in a RoundingError being thrown by the Exchange Contract.
+        const partiallyFillableMakerTokenAmount = fillableTimesInMakerTokenUnits
+                                                     .times(this.signedOrder.makerTokenAmount)
+                                                     .dividedToIntegerBy(this.signedOrder.makerFee);
+        const partiallyFillableFeeTokenAmount = fillableTimesInFeeTokenBaseUnits
+                                                     .times(this.signedOrder.makerTokenAmount)
+                                                     .dividedToIntegerBy(this.signedOrder.makerFee);
+        const partiallyFillableAmount = BigNumber.min(partiallyFillableMakerTokenAmount,
+                                                      partiallyFillableFeeTokenAmount);
+        return partiallyFillableAmount;
+    }
+}

packages/0x.js/src/schemas/zero_ex_config_schema.ts

@@ -0,0 +1,28 @@
+export const zeroExConfigSchema = {
+    id: '/ZeroExConfig',
+    properties: {
+        networkId: {
+            type: 'number',
+            minimum: 0,
+        },
+        gasPrice: {$ref: '/Number'},
+        exchangeContractAddress: {$ref: '/Address'},
+        tokenRegistryContractAddress: {$ref: '/Address'},
+        etherTokenContractAddress: {$ref: '/Address'},
+        orderWatcherConfig: {
+            type: 'object',
+            properties: {
+                pollingIntervalMs: {
+                    type: 'number',
+                    minimum: 0,
+                },
+                numConfirmations: {
+                    type: 'number',
+                    minimum: 0,
+                },
+            },
+        },
+    },
+    type: 'object',
+    required: ['networkId'],
+};

packages/0x.js/src/stores/balance_proxy_allowance_lazy_store.ts

@@ -0,0 +1,85 @@
+import {BigNumber} from 'bignumber.js';
+import * as _ from 'lodash';
+import * as Web3 from 'web3';
+
+import {TokenWrapper} from '../contract_wrappers/token_wrapper';
+import {BlockParamLiteral} from '../types';
+
+/**
+ * Copy on read store for balances/proxyAllowances of tokens/accounts
+ */
+export class BalanceAndProxyAllowanceLazyStore {
+    private token: TokenWrapper;
+    private defaultBlock: BlockParamLiteral;
+    private balance: {
+        [tokenAddress: string]: {
+            [userAddress: string]: BigNumber;
+        };
+    };
+    private proxyAllowance: {
+        [tokenAddress: string]: {
+            [userAddress: string]: BigNumber;
+        };
+    };
+    constructor(token: TokenWrapper, defaultBlock: BlockParamLiteral) {
+        this.token = token;
+        this.defaultBlock = defaultBlock;
+        this.balance = {};
+        this.proxyAllowance = {};
+    }
+    public async getBalanceAsync(tokenAddress: string, userAddress: string): Promise<BigNumber> {
+        if (_.isUndefined(this.balance[tokenAddress]) || _.isUndefined(this.balance[tokenAddress][userAddress])) {
+            const methodOpts = {
+                defaultBlock: this.defaultBlock,
+            };
+            const balance = await this.token.getBalanceAsync(tokenAddress, userAddress, methodOpts);
+            this.setBalance(tokenAddress, userAddress, balance);
+        }
+        const cachedBalance = this.balance[tokenAddress][userAddress];
+        return cachedBalance;
+    }
+    public setBalance(tokenAddress: string, userAddress: string, balance: BigNumber): void {
+        if (_.isUndefined(this.balance[tokenAddress])) {
+            this.balance[tokenAddress] = {};
+        }
+        this.balance[tokenAddress][userAddress] = balance;
+    }
+    public deleteBalance(tokenAddress: string, userAddress: string): void {
+        if (!_.isUndefined(this.balance[tokenAddress])) {
+            delete this.balance[tokenAddress][userAddress];
+            if (_.isEmpty(this.balance[tokenAddress])) {
+                delete this.balance[tokenAddress];
+            }
+        }
+    }
+    public async getProxyAllowanceAsync(tokenAddress: string, userAddress: string): Promise<BigNumber> {
+        if (_.isUndefined(this.proxyAllowance[tokenAddress]) ||
+            _.isUndefined(this.proxyAllowance[tokenAddress][userAddress])) {
+            const methodOpts = {
+                defaultBlock: this.defaultBlock,
+            };
+            const proxyAllowance = await this.token.getProxyAllowanceAsync(tokenAddress, userAddress, methodOpts);
+            this.setProxyAllowance(tokenAddress, userAddress, proxyAllowance);
+        }
+        const cachedProxyAllowance = this.proxyAllowance[tokenAddress][userAddress];
+        return cachedProxyAllowance;
+    }
+    public setProxyAllowance(tokenAddress: string, userAddress: string, proxyAllowance: BigNumber): void {
+        if (_.isUndefined(this.proxyAllowance[tokenAddress])) {
+            this.proxyAllowance[tokenAddress] = {};
+        }
+        this.proxyAllowance[tokenAddress][userAddress] = proxyAllowance;
+    }
+    public deleteProxyAllowance(tokenAddress: string, userAddress: string): void {
+        if (!_.isUndefined(this.proxyAllowance[tokenAddress])) {
+            delete this.proxyAllowance[tokenAddress][userAddress];
+            if (_.isEmpty(this.proxyAllowance[tokenAddress])) {
+                delete this.proxyAllowance[tokenAddress];
+            }
+        }
+    }
+    public deleteAll(): void {
+        this.balance = {};
+        this.proxyAllowance = {};
+    }
+}

packages/0x.js/src/stores/order_filled_cancelled_lazy_store.ts

@@ -0,0 +1,62 @@
+import {BigNumber} from 'bignumber.js';
+import * as _ from 'lodash';
+import * as Web3 from 'web3';
+
+import {ExchangeWrapper} from '../contract_wrappers/exchange_wrapper';
+import {BlockParamLiteral} from '../types';
+
+/**
+ * Copy on read store for filled/cancelled taker amounts
+ */
+export class OrderFilledCancelledLazyStore {
+    private exchange: ExchangeWrapper;
+    private filledTakerAmount: {
+        [orderHash: string]: BigNumber;
+    };
+    private cancelledTakerAmount: {
+        [orderHash: string]: BigNumber;
+    };
+    constructor(exchange: ExchangeWrapper) {
+        this.exchange = exchange;
+        this.filledTakerAmount = {};
+        this.cancelledTakerAmount = {};
+    }
+    public async getFilledTakerAmountAsync(orderHash: string): Promise<BigNumber> {
+        if (_.isUndefined(this.filledTakerAmount[orderHash])) {
+            const methodOpts = {
+                defaultBlock: BlockParamLiteral.Pending,
+            };
+            const filledTakerAmount = await this.exchange.getFilledTakerAmountAsync(orderHash, methodOpts);
+            this.setFilledTakerAmount(orderHash, filledTakerAmount);
+        }
+        const cachedFilled = this.filledTakerAmount[orderHash];
+        return cachedFilled;
+    }
+    public setFilledTakerAmount(orderHash: string, filledTakerAmount: BigNumber): void {
+        this.filledTakerAmount[orderHash] = filledTakerAmount;
+    }
+    public deleteFilledTakerAmount(orderHash: string): void {
+        delete this.filledTakerAmount[orderHash];
+    }
+    public async getCancelledTakerAmountAsync(orderHash: string): Promise<BigNumber> {
+        if (_.isUndefined(this.cancelledTakerAmount[orderHash])) {
+            const methodOpts = {
+                defaultBlock: BlockParamLiteral.Pending,
+            };
+            const cancelledTakerAmount = await this.exchange.getCancelledTakerAmountAsync(orderHash, methodOpts);
+            this.setCancelledTakerAmount(orderHash, cancelledTakerAmount);
+        }
+        const cachedCancelled = this.cancelledTakerAmount[orderHash];
+        return cachedCancelled;
+    }
+    public setCancelledTakerAmount(orderHash: string, cancelledTakerAmount: BigNumber): void {
+        this.cancelledTakerAmount[orderHash] = cancelledTakerAmount;
+    }
+    public deleteCancelledTakerAmount(orderHash: string): void {
+        delete this.cancelledTakerAmount[orderHash];
+    }
+    public deleteAll(): void {
+        this.filledTakerAmount = {};
+        this.cancelledTakerAmount = {};
+    }
+}

packages/0x.js/src/types.ts

@@ -1,8 +1,13 @@
+import BigNumber from 'bignumber.js';
 import * as Web3 from 'web3';
 
 export enum ZeroExError {
-    ContractDoesNotExist = 'CONTRACT_DOES_NOT_EXIST',
     ExchangeContractDoesNotExist = 'EXCHANGE_CONTRACT_DOES_NOT_EXIST',
+    ZRXContractDoesNotExist = 'ZRX_CONTRACT_DOES_NOT_EXIST',
+    EtherTokenContractDoesNotExist = 'ETHER_TOKEN_CONTRACT_DOES_NOT_EXIST',
+    TokenTransferProxyContractDoesNotExist = 'TOKEN_TRANSFER_PROXY_CONTRACT_DOES_NOT_EXIST',
+    TokenRegistryContractDoesNotExist = 'TOKEN_REGISTRY_CONTRACT_DOES_NOT_EXIST',
+    TokenContractDoesNotExist = 'TOKEN_CONTRACT_DOES_NOT_EXIST',
     UnhandledError = 'UNHANDLED_ERROR',
     UserHasNoAssociatedAddress = 'USER_HAS_NO_ASSOCIATED_ADDRESSES',
     InvalidSignature = 'INVALID_SIGNATURE',
@@ -14,6 +19,9 @@ export enum ZeroExError {
     InvalidJump = 'INVALID_JUMP',
     OutOfGas = 'OUT_OF_GAS',
     NoNetworkId = 'NO_NETWORK_ID',
+    SubscriptionNotFound = 'SUBSCRIPTION_NOT_FOUND',
+    SubscriptionAlreadyPresent = 'SUBSCRIPTION_ALREADY_PRESENT',
+    TransactionMiningTimeout = 'TRANSACTION_MINING_TIMEOUT',
 }
 
 export enum InternalZeroExError {
@@ -32,26 +40,23 @@ export interface ECSignature {
 
 export type OrderAddresses = [string, string, string, string, string];
 
-export type OrderValues = [BigNumber.BigNumber, BigNumber.BigNumber, BigNumber.BigNumber,
-                           BigNumber.BigNumber, BigNumber.BigNumber, BigNumber.BigNumber];
+export type OrderValues = [BigNumber, BigNumber, BigNumber,
+                           BigNumber, BigNumber, BigNumber];
 
-export type EventCallbackAsync = (err: Error, event: ContractEvent) => Promise<void>;
-export type EventCallbackSync = (err: Error, event: ContractEvent) => void;
-export type EventCallback = EventCallbackSync|EventCallbackAsync;
-export interface ContractEventObj {
-    watch: (eventWatch: EventCallback) => void;
-    stopWatching: () => void;
+export type LogEvent = Web3.LogEntryEvent;
+export interface DecodedLogEvent<ArgsType> {
+    isRemoved: boolean;
+    log: LogWithDecodedArgs<ArgsType>;
 }
-export type CreateContractEvent = (indexFilterValues: IndexedFilterValues,
-                                   subscriptionOpts: SubscriptionOpts) => ContractEventObj;
+
+export type EventCallback<ArgsType> = (err: null|Error, log?: DecodedLogEvent<ArgsType>) => void;
+export type EventWatcherCallback = (log: LogEvent) => void;
+
 export interface ExchangeContract extends Web3.ContractInstance {
     isValidSignature: {
         callAsync: (signerAddressHex: string, dataHex: string, v: number, r: string, s: string,
                     txOpts?: TxOpts) => Promise<boolean>;
     };
-    LogFill: CreateContractEvent;
-    LogCancel: CreateContractEvent;
-    LogError: CreateContractEvent;
     ZRX_TOKEN_CONTRACT: {
         callAsync: () => Promise<string>;
     };
@@ -59,77 +64,77 @@ export interface ExchangeContract extends Web3.ContractInstance {
         callAsync: () => Promise<string>;
     };
     getUnavailableTakerTokenAmount: {
-        callAsync: (orderHash: string, defaultBlock?: Web3.BlockParam) => Promise<BigNumber.BigNumber>;
+        callAsync: (orderHash: string, defaultBlock?: Web3.BlockParam) => Promise<BigNumber>;
     };
     isRoundingError: {
-        callAsync: (fillTakerAmount: BigNumber.BigNumber, takerTokenAmount: BigNumber.BigNumber,
-                    makerTokenAmount: BigNumber.BigNumber, txOpts?: TxOpts) => Promise<boolean>;
+        callAsync: (takerTokenFillAmount: BigNumber, takerTokenAmount: BigNumber,
+                    makerTokenAmount: BigNumber, txOpts?: TxOpts) => Promise<boolean>;
     };
     fillOrder: {
         sendTransactionAsync: (orderAddresses: OrderAddresses, orderValues: OrderValues,
-                               fillTakerTokenAmount: BigNumber.BigNumber,
+                               fillTakerTokenAmount: BigNumber,
                                shouldThrowOnInsufficientBalanceOrAllowance: boolean,
                                v: number, r: string, s: string, txOpts?: TxOpts) => Promise<string>;
         estimateGasAsync: (orderAddresses: OrderAddresses, orderValues: OrderValues,
-                           fillTakerTokenAmount: BigNumber.BigNumber,
+                           fillTakerTokenAmount: BigNumber,
                            shouldThrowOnInsufficientBalanceOrAllowance: boolean,
                            v: number, r: string, s: string, txOpts?: TxOpts) => Promise<number>;
     };
     batchFillOrders: {
         sendTransactionAsync: (orderAddresses: OrderAddresses[], orderValues: OrderValues[],
-                               fillTakerTokenAmounts: BigNumber.BigNumber[],
+                               fillTakerTokenAmounts: BigNumber[],
                                shouldThrowOnInsufficientBalanceOrAllowance: boolean,
                                v: number[], r: string[], s: string[], txOpts?: TxOpts) => Promise<string>;
         estimateGasAsync: (orderAddresses: OrderAddresses[], orderValues: OrderValues[],
-                           fillTakerTokenAmounts: BigNumber.BigNumber[],
+                           fillTakerTokenAmounts: BigNumber[],
                            shouldThrowOnInsufficientBalanceOrAllowance: boolean,
                            v: number[], r: string[], s: string[], txOpts?: TxOpts) => Promise<number>;
     };
     fillOrdersUpTo: {
         sendTransactionAsync: (orderAddresses: OrderAddresses[], orderValues: OrderValues[],
-                               fillTakerTokenAmount: BigNumber.BigNumber,
+                               fillTakerTokenAmount: BigNumber,
                                shouldThrowOnInsufficientBalanceOrAllowance: boolean,
                                v: number[], r: string[], s: string[], txOpts?: TxOpts) => Promise<string>;
         estimateGasAsync: (orderAddresses: OrderAddresses[], orderValues: OrderValues[],
-                           fillTakerTokenAmount: BigNumber.BigNumber,
+                           fillTakerTokenAmount: BigNumber,
                            shouldThrowOnInsufficientBalanceOrAllowance: boolean,
                            v: number[], r: string[], s: string[], txOpts?: TxOpts) => Promise<number>;
     };
     cancelOrder: {
         sendTransactionAsync: (orderAddresses: OrderAddresses, orderValues: OrderValues,
-                               cancelTakerTokenAmount: BigNumber.BigNumber, txOpts?: TxOpts) => Promise<string>;
+                               cancelTakerTokenAmount: BigNumber, txOpts?: TxOpts) => Promise<string>;
         estimateGasAsync: (orderAddresses: OrderAddresses, orderValues: OrderValues,
-                           cancelTakerTokenAmount: BigNumber.BigNumber,
+                           cancelTakerTokenAmount: BigNumber,
                            txOpts?: TxOpts) => Promise<number>;
     };
     batchCancelOrders: {
         sendTransactionAsync: (orderAddresses: OrderAddresses[], orderValues: OrderValues[],
-                               cancelTakerTokenAmounts: BigNumber.BigNumber[], txOpts?: TxOpts) => Promise<string>;
+                               cancelTakerTokenAmounts: BigNumber[], txOpts?: TxOpts) => Promise<string>;
         estimateGasAsync: (orderAddresses: OrderAddresses[], orderValues: OrderValues[],
-                           cancelTakerTokenAmounts: BigNumber.BigNumber[],
+                           cancelTakerTokenAmounts: BigNumber[],
                            txOpts?: TxOpts) => Promise<number>;
     };
     fillOrKillOrder: {
         sendTransactionAsync: (orderAddresses: OrderAddresses, orderValues: OrderValues,
-                               fillTakerTokenAmount: BigNumber.BigNumber,
+                               fillTakerTokenAmount: BigNumber,
                                v: number, r: string, s: string, txOpts?: TxOpts) => Promise<string>;
         estimateGasAsync: (orderAddresses: OrderAddresses, orderValues: OrderValues,
-                           fillTakerTokenAmount: BigNumber.BigNumber,
+                           fillTakerTokenAmount: BigNumber,
                            v: number, r: string, s: string, txOpts?: TxOpts) => Promise<number>;
     };
     batchFillOrKillOrders: {
         sendTransactionAsync: (orderAddresses: OrderAddresses[], orderValues: OrderValues[],
-                               fillTakerTokenAmounts: BigNumber.BigNumber[],
+                               fillTakerTokenAmounts: BigNumber[],
                                v: number[], r: string[], s: string[], txOpts: TxOpts) => Promise<string>;
         estimateGasAsync: (orderAddresses: OrderAddresses[], orderValues: OrderValues[],
-                           fillTakerTokenAmounts: BigNumber.BigNumber[],
+                           fillTakerTokenAmounts: BigNumber[],
                            v: number[], r: string[], s: string[], txOpts?: TxOpts) => Promise<number>;
     };
     filled: {
-        callAsync: (orderHash: string, defaultBlock?: Web3.BlockParam) => Promise<BigNumber.BigNumber>;
+        callAsync: (orderHash: string, defaultBlock?: Web3.BlockParam) => Promise<BigNumber>;
     };
     cancelled: {
-        callAsync: (orderHash: string, defaultBlock?: Web3.BlockParam) => Promise<BigNumber.BigNumber>;
+        callAsync: (orderHash: string, defaultBlock?: Web3.BlockParam) => Promise<BigNumber>;
     };
     getOrderHash: {
         callAsync: (orderAddresses: OrderAddresses, orderValues: OrderValues) => Promise<string>;
@@ -137,25 +142,23 @@ export interface ExchangeContract extends Web3.ContractInstance {
 }
 
 export interface TokenContract extends Web3.ContractInstance {
-    Transfer: CreateContractEvent;
-    Approval: CreateContractEvent;
     balanceOf: {
-        callAsync: (address: string, defaultBlock?: Web3.BlockParam) => Promise<BigNumber.BigNumber>;
+        callAsync: (address: string, defaultBlock?: Web3.BlockParam) => Promise<BigNumber>;
     };
     allowance: {
         callAsync: (ownerAddress: string, allowedAddress: string,
-                    defaultBlock?: Web3.BlockParam) => Promise<BigNumber.BigNumber>;
+                    defaultBlock?: Web3.BlockParam) => Promise<BigNumber>;
     };
     transfer: {
-        sendTransactionAsync: (toAddress: string, amountInBaseUnits: BigNumber.BigNumber,
+        sendTransactionAsync: (toAddress: string, amountInBaseUnits: BigNumber,
                                txOpts?: TxOpts) => Promise<string>;
     };
     transferFrom: {
-        sendTransactionAsync: (fromAddress: string, toAddress: string, amountInBaseUnits: BigNumber.BigNumber,
+        sendTransactionAsync: (fromAddress: string, toAddress: string, amountInBaseUnits: BigNumber,
                                txOpts?: TxOpts) => Promise<string>;
     };
     approve: {
-        sendTransactionAsync: (proxyAddress: string, amountInBaseUnits: BigNumber.BigNumber,
+        sendTransactionAsync: (proxyAddress: string, amountInBaseUnits: BigNumber,
                                txOpts?: TxOpts) => Promise<string>;
     };
 }
@@ -186,7 +189,7 @@ export interface EtherTokenContract extends Web3.ContractInstance {
         sendTransactionAsync: (txOpts: TxOpts) => Promise<string>;
     };
     withdraw: {
-        sendTransactionAsync: (amount: BigNumber.BigNumber, txOpts: TxOpts) => Promise<string>;
+        sendTransactionAsync: (amount: BigNumber, txOpts: TxOpts) => Promise<string>;
     };
 }
 
@@ -260,10 +263,10 @@ export interface LogFillContractEventArgs {
     feeRecipient: string;
     makerToken: string;
     takerToken: string;
-    filledMakerTokenAmount: BigNumber.BigNumber;
-    filledTakerTokenAmount: BigNumber.BigNumber;
-    paidMakerFee: BigNumber.BigNumber;
-    paidTakerFee: BigNumber.BigNumber;
+    filledMakerTokenAmount: BigNumber;
+    filledTakerTokenAmount: BigNumber;
+    paidMakerFee: BigNumber;
+    paidTakerFee: BigNumber;
     tokens: string;
     orderHash: string;
 }
@@ -272,43 +275,43 @@ export interface LogCancelContractEventArgs {
     feeRecipient: string;
     makerToken: string;
     takerToken: string;
-    cancelledMakerTokenAmount: BigNumber.BigNumber;
-    cancelledTakerTokenAmount: BigNumber.BigNumber;
+    cancelledMakerTokenAmount: BigNumber;
+    cancelledTakerTokenAmount: BigNumber;
     tokens: string;
     orderHash: string;
 }
 export interface LogErrorContractEventArgs {
-    errorId: BigNumber.BigNumber;
+    errorId: BigNumber;
     orderHash: string;
 }
 export type ExchangeContractEventArgs = LogFillContractEventArgs|LogCancelContractEventArgs|LogErrorContractEventArgs;
 export interface TransferContractEventArgs {
     _from: string;
     _to: string;
-    _value: BigNumber.BigNumber;
+    _value: BigNumber;
 }
 export interface ApprovalContractEventArgs {
     _owner: string;
     _spender: string;
-    _value: BigNumber.BigNumber;
+    _value: BigNumber;
 }
 export type TokenContractEventArgs = TransferContractEventArgs|ApprovalContractEventArgs;
 export type ContractEventArgs = ExchangeContractEventArgs|TokenContractEventArgs;
-export type ContractEventArg = string|BigNumber.BigNumber;
+export type ContractEventArg = string|BigNumber;
 
 export interface Order {
     maker: string;
     taker: string;
-    makerFee: BigNumber.BigNumber;
-    takerFee: BigNumber.BigNumber;
-    makerTokenAmount: BigNumber.BigNumber;
-    takerTokenAmount: BigNumber.BigNumber;
+    makerFee: BigNumber;
+    takerFee: BigNumber;
+    makerTokenAmount: BigNumber;
+    takerTokenAmount: BigNumber;
     makerTokenAddress: string;
     takerTokenAddress: string;
-    salt: BigNumber.BigNumber;
+    salt: BigNumber;
     exchangeContractAddress: string;
     feeRecipient: string;
-    expirationUnixTimestampSec: BigNumber.BigNumber;
+    expirationUnixTimestampSec: BigNumber;
 }
 
 export interface SignedOrder extends Order {
@@ -316,7 +319,7 @@ export interface SignedOrder extends Order {
 }
 
 //                          [address, name, symbol, decimals, ipfsHash, swarmHash]
-export type TokenMetadata = [string, string, string, BigNumber.BigNumber, string, string];
+export type TokenMetadata = [string, string, string, BigNumber, string, string];
 
 export interface Token {
     name: string;
@@ -328,7 +331,8 @@ export interface Token {
 export interface TxOpts {
     from: string;
     gas?: number;
-    value?: BigNumber.BigNumber;
+    value?: BigNumber;
+    gasPrice?: BigNumber;
 }
 
 export interface TokenAddressBySymbol {
@@ -352,7 +356,15 @@ export interface IndexedFilterValues {
     [index: string]: ContractEventArg;
 }
 
-export type BlockParam = 'latest'|'earliest'|'pending'|number;
+// Earliest is omitted by design. It is simply an alias for the `0` constant and
+// is thus not very helpful. Moreover, this type is used in places that only accept
+// `latest` or `pending`.
+export enum BlockParamLiteral {
+    Latest = 'latest',
+    Pending = 'pending',
+}
+
+export type BlockParam = BlockParamLiteral|number;
 
 export interface SubscriptionOpts {
     fromBlock: BlockParam;
@@ -361,32 +373,23 @@ export interface SubscriptionOpts {
 
 export type DoneCallback = (err?: Error) => void;
 
-export interface OrderFillOrKillRequest {
-    signedOrder: SignedOrder;
-    fillTakerAmount: BigNumber.BigNumber;
-}
-
 export interface OrderCancellationRequest {
     order: Order|SignedOrder;
-    takerTokenCancelAmount: BigNumber.BigNumber;
+    takerTokenCancelAmount: BigNumber;
 }
 
 export interface OrderFillRequest {
     signedOrder: SignedOrder;
-    takerTokenFillAmount: BigNumber.BigNumber;
+    takerTokenFillAmount: BigNumber;
 }
 
 export type AsyncMethod = (...args: any[]) => Promise<any>;
 
-export interface ContractEventEmitter {
-    watch: (eventCallback: EventCallback) => void;
-    stopWatchingAsync: () => Promise<void>;
-}
-
 /**
  * We re-export the `Web3.Provider` type specified in the Web3 Typescript typings
  * since it is the type of the `provider` argument to the `ZeroEx` constructor.
- * It is however a `Web3` library type, not a native `0x.js` type.
+ * It is however a `Web3` library type, not a native `0x.js` type. To learn more
+ * about providers, visit https://0xproject.com/wiki#Web3-Provider-Explained
  */
 export type Web3Provider = Web3.Provider;
 
@@ -400,20 +403,38 @@ export interface JSONRPCPayload {
 }
 
 /*
+ * orderExpirationCheckingIntervalMs: How often to check for expired orders. Default: 50
+ * eventPollingIntervalMs: How often to poll the Ethereum node for new events. Defaults: 200
+ * expirationMarginMs: Amount of time before order expiry that you'd like to be notified
+ * of an orders expiration. Defaults: 0
+ * cleanupJobIntervalMs: How often to run a cleanup job which revalidates all the orders. Defaults: 1h
+ */
+export interface OrderStateWatcherConfig {
+    orderExpirationCheckingIntervalMs?: number;
+    eventPollingIntervalMs?: number;
+    expirationMarginMs?: number;
+    cleanupJobIntervalMs?: number;
+}
+
+/*
+ * networkId: The id of the underlying ethereum network your provider is connected to. (1-mainnet, 42-kovan, 50-testrpc)
  * gasPrice: Gas price to use with every transaction
  * exchangeContractAddress: The address of an exchange contract to use
  * tokenRegistryContractAddress: The address of a token registry contract to use
  * etherTokenContractAddress: The address of an ether token contract to use
+ * tokenTransferProxyContractAddress: The address of the token transfer proxy contract to use
+ * orderWatcherConfig: All the configs related to the orderWatcher
  */
 export interface ZeroExConfig {
-    gasPrice?: BigNumber.BigNumber; // Gas price to use with every transaction
+    networkId: number;
+    gasPrice?: BigNumber;
     exchangeContractAddress?: string;
     tokenRegistryContractAddress?: string;
     etherTokenContractAddress?: string;
+    tokenTransferProxyContractAddress?: string;
+    orderWatcherConfig?: OrderStateWatcherConfig;
 }
 
-export type TransactionReceipt = Web3.TransactionReceipt;
-
 export enum AbiType {
     Function = 'function',
     Constructor = 'constructor',
@@ -425,22 +446,22 @@ export interface DecodedLogArgs {
     [argName: string]: ContractEventArg;
 }
 
-export interface DecodedArgs {
-    args: DecodedLogArgs;
-    event: string;
+export interface LogWithDecodedArgs<ArgsType> extends Web3.DecodedLogEntry<ArgsType> {}
+
+export interface TransactionReceiptWithDecodedLogs extends TransactionReceipt {
+    logs: Array<LogWithDecodedArgs<DecodedLogArgs>|Web3.LogEntry>;
 }
 
-export interface LogWithDecodedArgs extends Web3.LogEntry, DecodedArgs {}
-
-export interface TransactionReceiptWithDecodedLogs extends Web3.TransactionReceipt {
-    logs: Array<LogWithDecodedArgs|Web3.LogEntry>;
-}
+export type ArtifactContractName = 'ZRX'|'TokenTransferProxy'|'TokenRegistry'|'Token'|'Exchange'|'EtherToken';
 
 export interface Artifact {
-    abi: any;
-    networks: {[networkId: number]: {
-        address: string;
-    }};
+    contract_name: ArtifactContractName;
+    abi: Web3.ContractAbi;
+    networks: {
+        [networkId: number]: {
+            address: string;
+        };
+    };
 }
 
 /*
@@ -450,7 +471,7 @@ export interface Artifact {
  * allowance/balance to fill the entire remaining order amount.
  */
 export interface ValidateOrderFillableOpts {
-    expectedFillTakerTokenAmount?: BigNumber.BigNumber;
+    expectedFillTakerTokenAmount?: BigNumber;
 }
 
 /*
@@ -464,11 +485,71 @@ export interface MethodOpts {
 }
 
 /*
- * shouldValidate: Flag indicating whether the library should make attempts to validate a transaction before
- * broadcasting it. For example, order has a valid signature, maker has sufficient funds, etc.
+ * gasPrice: Gas price in Wei to use for a transaction
+ * gasLimit: The amount of gas to send with a transaction
  */
-export interface OrderTransactionOpts {
-    shouldValidate: boolean;
+export interface TransactionOpts {
+    gasPrice?: BigNumber;
+    gasLimit?: number;
+}
+
+/*
+ * shouldValidate: Flag indicating whether the library should make attempts to validate a transaction before
+ * broadcasting it. For example, order has a valid signature, maker has sufficient funds, etc. Default: true
+ */
+export interface OrderTransactionOpts extends TransactionOpts {
+    shouldValidate?: boolean;
 }
 
 export type FilterObject = Web3.FilterObject;
+
+export enum TradeSide {
+    Maker = 'maker',
+    Taker = 'taker',
+}
+
+export enum TransferType {
+    Trade = 'trade',
+    Fee = 'fee',
+}
+
+export interface OrderRelevantState {
+    makerBalance: BigNumber;
+    makerProxyAllowance: BigNumber;
+    makerFeeBalance: BigNumber;
+    makerFeeProxyAllowance: BigNumber;
+    filledTakerTokenAmount: BigNumber;
+    cancelledTakerTokenAmount: BigNumber;
+    remainingFillableMakerTokenAmount: BigNumber;
+    remainingFillableTakerTokenAmount: BigNumber;
+}
+
+export interface OrderStateValid {
+    isValid: true;
+    orderHash: string;
+    orderRelevantState: OrderRelevantState;
+}
+
+export interface OrderStateInvalid {
+    isValid: false;
+    orderHash: string;
+    error: ExchangeContractErrs;
+}
+
+export type OrderState = OrderStateValid|OrderStateInvalid;
+
+export type OnOrderStateChangeCallback = (orderState: OrderState) => void;
+
+export interface TransactionReceipt {
+    blockHash: string;
+    blockNumber: number;
+    transactionHash: string;
+    transactionIndex: number;
+    from: string;
+    to: string;
+    status: null|0|1;
+    cumulativeGasUsed: number;
+    gasUsed: number;
+    contractAddress: string|null;
+    logs: Web3.LogEntry[];
+} // tslint:disable:max-file-line-count

packages/0x.js/src/utils/abi_decoder.ts

@@ -1,17 +1,28 @@
-import * as Web3 from 'web3';
+import BigNumber from 'bignumber.js';
 import * as _ from 'lodash';
-import * as BigNumber from 'bignumber.js';
-import {AbiType, DecodedLogArgs, DecodedArgs, LogWithDecodedArgs, RawLog, SolidityTypes} from '../types';
+import * as Web3 from 'web3';
 import * as SolidityCoder from 'web3/lib/solidity/coder';
 
+import {AbiType, ContractEventArgs, DecodedLogArgs, LogWithDecodedArgs, RawLog, SolidityTypes} from '../types';
+
 export class AbiDecoder {
     private savedABIs: Web3.AbiDefinition[] = [];
     private methodIds: {[signatureHash: string]: Web3.EventAbi} = {};
+    private static padZeros(address: string) {
+        let formatted = address;
+        if (_.startsWith(formatted, '0x')) {
+            formatted = formatted.slice(2);
+        }
+
+        formatted = _.padStart(formatted, 40, '0');
+        return `0x${formatted}`;
+    }
     constructor(abiArrays: Web3.AbiDefinition[][]) {
         _.map(abiArrays, this.addABI.bind(this));
     }
-    // This method can only decode logs from the 0x smart contracts
-    public tryToDecodeLogOrNoop(log: Web3.LogEntry): LogWithDecodedArgs|RawLog {
+    // This method can only decode logs from the 0x & ERC20 smart contracts
+    public tryToDecodeLogOrNoop<ArgsType extends ContractEventArgs>(
+        log: Web3.LogEntry): LogWithDecodedArgs<ArgsType>|RawLog {
         const methodId = log.topics[0];
         const event = this.methodIds[methodId];
         if (_.isUndefined(event)) {
@@ -30,10 +41,10 @@ export class AbiDecoder {
             // Indexed parameters are stored in topics. Non-indexed ones in decodedData
             let value = param.indexed ? log.topics[topicsIndex++] : decodedData[dataIndex++];
             if (param.type === SolidityTypes.Address) {
-                value = this.padZeros(new BigNumber(value).toString(16));
+                value = AbiDecoder.padZeros(new BigNumber(value).toString(16));
             } else if (param.type === SolidityTypes.Uint256 ||
                        param.type === SolidityTypes.Uint8 ||
-                       param.type === SolidityTypes.Uint ) {
+                       param.type === SolidityTypes.Uint) {
                 value = new BigNumber(value);
             }
             decodedParams[param.name] = value;
@@ -55,13 +66,4 @@ export class AbiDecoder {
         });
         this.savedABIs = this.savedABIs.concat(abiArray);
     }
-    private padZeros(address: string) {
-        let formatted = address;
-        if (_.startsWith(formatted, '0x')) {
-            formatted = formatted.slice(2);
-        }
-
-        formatted = _.padStart(formatted, 40, '0');
-        return `0x${formatted}`;
-    }
 }

packages/0x.js/src/utils/assert.ts

@@ -0,0 +1,31 @@
+import {assert as sharedAssert} from '@0xproject/assert';
+import {Schema, SchemaValidator} from '@0xproject/json-schemas';
+import BigNumber from 'bignumber.js';
+import * as _ from 'lodash';
+import * as Web3 from 'web3';
+
+import {ECSignature} from '../types';
+import {signatureUtils} from '../utils/signature_utils';
+import {Web3Wrapper} from '../web3_wrapper';
+
+const HEX_REGEX = /^0x[0-9A-F]*$/i;
+
+export const assert = {
+    ...sharedAssert,
+    isValidSignature(orderHash: string, ecSignature: ECSignature, signerAddress: string) {
+        const isValidSignature = signatureUtils.isValidSignature(orderHash, ecSignature, signerAddress);
+        this.assert(isValidSignature, `Expected order with hash '${orderHash}' to have a valid signature`);
+    },
+    async isSenderAddressAsync(variableName: string, senderAddressHex: string,
+                               web3Wrapper: Web3Wrapper): Promise<void> {
+        sharedAssert.isETHAddressHex(variableName, senderAddressHex);
+        const isSenderAddressAvailable = await web3Wrapper.isSenderAddressAvailableAsync(senderAddressHex);
+        sharedAssert.assert(isSenderAddressAvailable,
+            `Specified ${variableName} ${senderAddressHex} isn't available through the supplied web3 provider`,
+        );
+    },
+    async isUserAddressAvailableAsync(web3Wrapper: Web3Wrapper): Promise<void> {
+        const availableAddresses = await web3Wrapper.getAvailableAddressesAsync();
+        this.assert(!_.isEmpty(availableAddresses), 'No addresses were available on the provided web3 provider');
+    },
+};

packages/0x.js/src/utils/constants.ts

@@ -1,4 +1,4 @@
-import * as BigNumber from 'bignumber.js';
+import BigNumber from 'bignumber.js';
 
 export const constants = {
     NULL_ADDRESS: '0x0000000000000000000000000000000000000000',
@@ -7,4 +7,5 @@ export const constants = {
     INVALID_JUMP_PATTERN: 'invalid JUMP at',
     OUT_OF_GAS_PATTERN: 'out of gas',
     UNLIMITED_ALLOWANCE_IN_BASE_UNITS: new BigNumber(2).pow(256).minus(1),
+    DEFAULT_BLOCK_POLLING_INTERVAL: 1000,
 };

packages/0x.js/src/utils/decorators.ts

@@ -1,7 +1,9 @@
 import * as _ from 'lodash';
-import {constants} from './constants';
+
 import {AsyncMethod, ZeroExError} from '../types';
 
+import {constants} from './constants';
+
 export const decorators = {
     /**
      * Source: https://stackoverflow.com/a/29837695/3546986

packages/0x.js/src/utils/exchange_transfer_simulator.ts

@@ -0,0 +1,89 @@
+import BigNumber from 'bignumber.js';
+import * as _ from 'lodash';
+
+import {TokenWrapper} from '../contract_wrappers/token_wrapper';
+import {BalanceAndProxyAllowanceLazyStore} from '../stores/balance_proxy_allowance_lazy_store';
+import {BlockParamLiteral, ExchangeContractErrs, TradeSide, TransferType} from '../types';
+
+enum FailureReason {
+    Balance = 'balance',
+    ProxyAllowance = 'proxyAllowance',
+}
+
+const ERR_MSG_MAPPING = {
+    [FailureReason.Balance]: {
+        [TradeSide.Maker]: {
+            [TransferType.Trade]: ExchangeContractErrs.InsufficientMakerBalance,
+            [TransferType.Fee]: ExchangeContractErrs.InsufficientMakerFeeBalance,
+        },
+        [TradeSide.Taker]: {
+            [TransferType.Trade]: ExchangeContractErrs.InsufficientTakerBalance,
+            [TransferType.Fee]: ExchangeContractErrs.InsufficientTakerFeeBalance,
+        },
+    },
+    [FailureReason.ProxyAllowance]: {
+        [TradeSide.Maker]: {
+            [TransferType.Trade]: ExchangeContractErrs.InsufficientMakerAllowance,
+            [TransferType.Fee]: ExchangeContractErrs.InsufficientMakerFeeAllowance,
+        },
+        [TradeSide.Taker]: {
+            [TransferType.Trade]: ExchangeContractErrs.InsufficientTakerAllowance,
+            [TransferType.Fee]: ExchangeContractErrs.InsufficientTakerFeeAllowance,
+        },
+    },
+};
+
+export class ExchangeTransferSimulator {
+    private store: BalanceAndProxyAllowanceLazyStore;
+    private UNLIMITED_ALLOWANCE_IN_BASE_UNITS: BigNumber;
+    private static throwValidationError(failureReason: FailureReason, tradeSide: TradeSide,
+                                        transferType: TransferType): never {
+        const errMsg = ERR_MSG_MAPPING[failureReason][tradeSide][transferType];
+        throw new Error(errMsg);
+    }
+    constructor(token: TokenWrapper, defaultBlock: BlockParamLiteral) {
+        this.store = new BalanceAndProxyAllowanceLazyStore(token, defaultBlock);
+        this.UNLIMITED_ALLOWANCE_IN_BASE_UNITS = token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS;
+    }
+    /**
+     * Simulates transferFrom call performed by a proxy
+     * @param  tokenAddress      Address of the token to be transferred
+     * @param  from              Owner of the transferred tokens
+     * @param  to                Recipient of the transferred tokens
+     * @param  amountInBaseUnits The amount of tokens being transferred
+     * @param  tradeSide         Is Maker/Taker transferring
+     * @param  transferType      Is it a fee payment or a value transfer
+     */
+    public async transferFromAsync(tokenAddress: string, from: string, to: string,
+                                   amountInBaseUnits: BigNumber, tradeSide: TradeSide,
+                                   transferType: TransferType): Promise<void> {
+        const balance = await this.store.getBalanceAsync(tokenAddress, from);
+        const proxyAllowance = await this.store.getProxyAllowanceAsync(tokenAddress, from);
+        if (proxyAllowance.lessThan(amountInBaseUnits)) {
+            ExchangeTransferSimulator.throwValidationError(FailureReason.ProxyAllowance, tradeSide, transferType);
+        }
+        if (balance.lessThan(amountInBaseUnits)) {
+            ExchangeTransferSimulator.throwValidationError(FailureReason.Balance, tradeSide, transferType);
+        }
+        await this.decreaseProxyAllowanceAsync(tokenAddress, from, amountInBaseUnits);
+        await this.decreaseBalanceAsync(tokenAddress, from, amountInBaseUnits);
+        await this.increaseBalanceAsync(tokenAddress, to, amountInBaseUnits);
+    }
+    private async decreaseProxyAllowanceAsync(tokenAddress: string, userAddress: string,
+                                              amountInBaseUnits: BigNumber): Promise<void> {
+        const proxyAllowance = await this.store.getProxyAllowanceAsync(tokenAddress, userAddress);
+        if (!proxyAllowance.eq(this.UNLIMITED_ALLOWANCE_IN_BASE_UNITS)) {
+            this.store.setProxyAllowance(tokenAddress, userAddress, proxyAllowance.minus(amountInBaseUnits));
+        }
+    }
+    private async increaseBalanceAsync(tokenAddress: string, userAddress: string,
+                                       amountInBaseUnits: BigNumber): Promise<void> {
+        const balance = await this.store.getBalanceAsync(tokenAddress, userAddress);
+        this.store.setBalance(tokenAddress, userAddress, balance.plus(amountInBaseUnits));
+    }
+    private async decreaseBalanceAsync(tokenAddress: string, userAddress: string,
+                                       amountInBaseUnits: BigNumber): Promise<void> {
+        const balance = await this.store.getBalanceAsync(tokenAddress, userAddress);
+        this.store.setBalance(tokenAddress, userAddress, balance.minus(amountInBaseUnits));
+    }
+}

packages/0x.js/src/utils/filter_utils.ts

@@ -0,0 +1,83 @@
+import * as ethUtil from 'ethereumjs-util';
+import * as jsSHA3 from 'js-sha3';
+import * as _ from 'lodash';
+import * as uuid from 'uuid/v4';
+import * as Web3 from 'web3';
+
+import {ContractEvents, IndexedFilterValues, SubscriptionOpts} from '../types';
+
+const TOPIC_LENGTH = 32;
+
+export const filterUtils = {
+    generateUUID(): string {
+        return uuid();
+    },
+    getFilter(address: string, eventName: ContractEvents,
+              indexFilterValues: IndexedFilterValues, abi: Web3.ContractAbi,
+              subscriptionOpts?: SubscriptionOpts): Web3.FilterObject {
+        const eventAbi = _.find(abi, {name: eventName}) as Web3.EventAbi;
+        const eventSignature = filterUtils.getEventSignatureFromAbiByName(eventAbi, eventName);
+        const topicForEventSignature = ethUtil.addHexPrefix(jsSHA3.keccak256(eventSignature));
+        const topicsForIndexedArgs = filterUtils.getTopicsForIndexedArgs(eventAbi, indexFilterValues);
+        const topics = [topicForEventSignature, ...topicsForIndexedArgs];
+        let filter: Web3.FilterObject = {
+            address,
+            topics,
+        };
+        if (!_.isUndefined(subscriptionOpts)) {
+            filter = {
+                ...subscriptionOpts,
+                ...filter,
+            };
+        }
+        return filter;
+    },
+    getEventSignatureFromAbiByName(eventAbi: Web3.EventAbi, eventName: ContractEvents): string {
+        const types = _.map(eventAbi.inputs, 'type');
+        const signature = `${eventAbi.name}(${types.join(',')})`;
+        return signature;
+    },
+    getTopicsForIndexedArgs(abi: Web3.EventAbi, indexFilterValues: IndexedFilterValues): Array<string|null> {
+        const topics: Array<string|null> = [];
+        for (const eventInput of abi.inputs) {
+            if (!eventInput.indexed) {
+                continue;
+            }
+            if (_.isUndefined(indexFilterValues[eventInput.name])) {
+                // Null is a wildcard topic in a JSON-RPC call
+                topics.push(null);
+            } else {
+                const value = indexFilterValues[eventInput.name] as string;
+                const buffer = ethUtil.toBuffer(value);
+                const paddedBuffer = ethUtil.setLengthLeft(buffer, TOPIC_LENGTH);
+                const topic = ethUtil.bufferToHex(paddedBuffer);
+                topics.push(topic);
+            }
+        }
+        return topics;
+    },
+    matchesFilter(log: Web3.LogEntry, filter: Web3.FilterObject): boolean {
+        if (!_.isUndefined(filter.address) && log.address !== filter.address) {
+            return false;
+        }
+        if (!_.isUndefined(filter.topics)) {
+            return filterUtils.matchesTopics(log.topics, filter.topics);
+        }
+        return true;
+    },
+    matchesTopics(logTopics: string[], filterTopics: Array<string[]|string|null>): boolean {
+        const matchesTopic = _.zipWith(logTopics, filterTopics, filterUtils.matchesTopic.bind(filterUtils));
+        const matchesTopics = _.every(matchesTopic);
+        return matchesTopics;
+    },
+    matchesTopic(logTopic: string, filterTopic: string[]|string|null): boolean {
+        if (_.isArray(filterTopic)) {
+            return _.includes(filterTopic, logTopic);
+        }
+        if (_.isString(filterTopic)) {
+            return filterTopic === logTopic;
+        }
+        // null topic is a wildcard
+        return true;
+    },
+};

packages/0x.js/src/utils/order_state_utils.ts

@@ -0,0 +1,137 @@
+import BigNumber from 'bignumber.js';
+import * as _ from 'lodash';
+import * as Web3 from 'web3';
+
+import {ZeroEx} from '../0x';
+import {ExchangeWrapper} from '../contract_wrappers/exchange_wrapper';
+import {TokenWrapper} from '../contract_wrappers/token_wrapper';
+import {RemainingFillableCalculator} from '../order_watcher/remaining_fillable_calculator';
+import {BalanceAndProxyAllowanceLazyStore} from '../stores/balance_proxy_allowance_lazy_store';
+import {OrderFilledCancelledLazyStore} from '../stores/order_filled_cancelled_lazy_store';
+import {
+    ExchangeContractErrs,
+    MethodOpts,
+    OrderRelevantState,
+    OrderState,
+    OrderStateInvalid,
+    OrderStateValid,
+    SignedOrder,
+} from '../types';
+import {constants} from '../utils/constants';
+import {utils} from '../utils/utils';
+
+const ACCEPTABLE_RELATIVE_ROUNDING_ERROR = 0.0001;
+
+export class OrderStateUtils {
+    private balanceAndProxyAllowanceLazyStore: BalanceAndProxyAllowanceLazyStore;
+    private orderFilledCancelledLazyStore: OrderFilledCancelledLazyStore;
+    private static validateIfOrderIsValid(signedOrder: SignedOrder, orderRelevantState: OrderRelevantState): void {
+        const unavailableTakerTokenAmount = orderRelevantState.cancelledTakerTokenAmount.add(
+            orderRelevantState.filledTakerTokenAmount,
+        );
+        const availableTakerTokenAmount = signedOrder.takerTokenAmount.minus(unavailableTakerTokenAmount);
+        if (availableTakerTokenAmount.eq(0)) {
+            throw new Error(ExchangeContractErrs.OrderRemainingFillAmountZero);
+        }
+
+        if (orderRelevantState.makerBalance.eq(0)) {
+            throw new Error(ExchangeContractErrs.InsufficientMakerBalance);
+        }
+        if (orderRelevantState.makerProxyAllowance.eq(0)) {
+            throw new Error(ExchangeContractErrs.InsufficientMakerAllowance);
+        }
+        if (!signedOrder.makerFee.eq(0)) {
+            if (orderRelevantState.makerFeeBalance.eq(0)) {
+                throw new Error(ExchangeContractErrs.InsufficientMakerFeeBalance);
+            }
+            if (orderRelevantState.makerFeeProxyAllowance.eq(0)) {
+                throw new Error(ExchangeContractErrs.InsufficientMakerFeeAllowance);
+            }
+        }
+        const minFillableTakerTokenAmountWithinNoRoundingErrorRange = signedOrder.takerTokenAmount
+                                                                      .dividedBy(ACCEPTABLE_RELATIVE_ROUNDING_ERROR)
+                                                                      .dividedBy(signedOrder.makerTokenAmount);
+        if (orderRelevantState.remainingFillableTakerTokenAmount
+            .lessThan(minFillableTakerTokenAmountWithinNoRoundingErrorRange)) {
+            throw new Error(ExchangeContractErrs.OrderFillRoundingError);
+        }
+    }
+    constructor(balanceAndProxyAllowanceLazyStore: BalanceAndProxyAllowanceLazyStore,
+                orderFilledCancelledLazyStore: OrderFilledCancelledLazyStore) {
+        this.balanceAndProxyAllowanceLazyStore = balanceAndProxyAllowanceLazyStore;
+        this.orderFilledCancelledLazyStore = orderFilledCancelledLazyStore;
+    }
+    public async getOrderStateAsync(signedOrder: SignedOrder): Promise<OrderState> {
+        const orderRelevantState = await this.getOrderRelevantStateAsync(signedOrder);
+        const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+        try {
+            OrderStateUtils.validateIfOrderIsValid(signedOrder, orderRelevantState);
+            const orderState: OrderStateValid = {
+                isValid: true,
+                orderHash,
+                orderRelevantState,
+            };
+            return orderState;
+        } catch (err) {
+            const orderState: OrderStateInvalid = {
+                isValid: false,
+                orderHash,
+                error: err.message,
+            };
+            return orderState;
+        }
+    }
+    public async getOrderRelevantStateAsync(signedOrder: SignedOrder): Promise<OrderRelevantState> {
+        // HACK: We access the private property here but otherwise the interface will be less nice.
+        // If we pass it from the instantiator - there is no opportunity to get it there
+        // because JS doesn't support async constructors.
+        // Moreover - it's cached under the hood so it's equivalent to an async constructor.
+        const exchange = (this.orderFilledCancelledLazyStore as any).exchange as ExchangeWrapper;
+        const zrxTokenAddress = exchange.getZRXTokenAddress();
+        const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+        const makerBalance = await this.balanceAndProxyAllowanceLazyStore.getBalanceAsync(
+            signedOrder.makerTokenAddress, signedOrder.maker,
+        );
+        const makerProxyAllowance = await this.balanceAndProxyAllowanceLazyStore.getProxyAllowanceAsync(
+            signedOrder.makerTokenAddress, signedOrder.maker,
+        );
+        const makerFeeBalance = await this.balanceAndProxyAllowanceLazyStore.getBalanceAsync(
+            zrxTokenAddress, signedOrder.maker,
+        );
+        const makerFeeProxyAllowance = await this.balanceAndProxyAllowanceLazyStore.getProxyAllowanceAsync(
+            zrxTokenAddress, signedOrder.maker,
+        );
+        const filledTakerTokenAmount = await this.orderFilledCancelledLazyStore.getFilledTakerAmountAsync(orderHash);
+        const cancelledTakerTokenAmount = await this.orderFilledCancelledLazyStore.getCancelledTakerAmountAsync(
+            orderHash,
+        );
+        const unavailableTakerTokenAmount = await exchange.getUnavailableTakerAmountAsync(orderHash);
+        const totalMakerTokenAmount = signedOrder.makerTokenAmount;
+        const totalTakerTokenAmount = signedOrder.takerTokenAmount;
+        const remainingTakerTokenAmount = totalTakerTokenAmount.minus(unavailableTakerTokenAmount);
+        const remainingMakerTokenAmount = remainingTakerTokenAmount.times(totalMakerTokenAmount)
+                                                                   .dividedToIntegerBy(totalTakerTokenAmount);
+        const transferrableMakerTokenAmount = BigNumber.min([makerProxyAllowance, makerBalance]);
+        const transferrableFeeTokenAmount = BigNumber.min([makerFeeProxyAllowance, makerFeeBalance]);
+
+        const isMakerTokenZRX = signedOrder.makerTokenAddress === zrxTokenAddress;
+        const remainingFillableCalculator = new RemainingFillableCalculator(signedOrder,
+                                                isMakerTokenZRX,
+                                                transferrableMakerTokenAmount,
+                                                transferrableFeeTokenAmount,
+                                                remainingMakerTokenAmount);
+        const remainingFillableMakerTokenAmount = remainingFillableCalculator.computeRemainingMakerFillable();
+        const remainingFillableTakerTokenAmount = remainingFillableCalculator.computeRemainingTakerFillable();
+        const orderRelevantState = {
+            makerBalance,
+            makerProxyAllowance,
+            makerFeeBalance,
+            makerFeeProxyAllowance,
+            filledTakerTokenAmount,
+            cancelledTakerTokenAmount,
+            remainingFillableMakerTokenAmount,
+            remainingFillableTakerTokenAmount,
+        };
+        return orderRelevantState;
+    }
+}

packages/0x.js/src/utils/order_validation_utils.ts

@@ -0,0 +1,168 @@
+import BigNumber from 'bignumber.js';
+import * as _ from 'lodash';
+
+import {ZeroEx} from '../0x';
+import {ExchangeWrapper} from '../contract_wrappers/exchange_wrapper';
+import {TokenWrapper} from '../contract_wrappers/token_wrapper';
+import {ExchangeContractErrs, Order, SignedOrder, TradeSide, TransferType, ZeroExError} from '../types';
+import {constants} from '../utils/constants';
+import {utils} from '../utils/utils';
+
+import {ExchangeTransferSimulator} from './exchange_transfer_simulator';
+
+export class OrderValidationUtils {
+    private tokenWrapper: TokenWrapper;
+    private exchangeWrapper: ExchangeWrapper;
+    public static validateCancelOrderThrowIfInvalid(
+        order: Order, cancelTakerTokenAmount: BigNumber, unavailableTakerTokenAmount: BigNumber,
+    ): void {
+        if (cancelTakerTokenAmount.eq(0)) {
+            throw new Error(ExchangeContractErrs.OrderCancelAmountZero);
+        }
+        if (order.takerTokenAmount.eq(unavailableTakerTokenAmount)) {
+            throw new Error(ExchangeContractErrs.OrderAlreadyCancelledOrFilled);
+        }
+        const currentUnixTimestampSec = utils.getCurrentUnixTimestampSec();
+        if (order.expirationUnixTimestampSec.lessThan(currentUnixTimestampSec)) {
+            throw new Error(ExchangeContractErrs.OrderCancelExpired);
+        }
+    }
+    public static async validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+        exchangeTradeEmulator: ExchangeTransferSimulator, signedOrder: SignedOrder,
+        fillTakerTokenAmount: BigNumber, senderAddress: string, zrxTokenAddress: string,
+    ): Promise<void> {
+        const fillMakerTokenAmount = OrderValidationUtils.getPartialAmount(
+            fillTakerTokenAmount,
+            signedOrder.takerTokenAmount,
+            signedOrder.makerTokenAmount,
+        );
+        await exchangeTradeEmulator.transferFromAsync(
+            signedOrder.makerTokenAddress, signedOrder.maker, senderAddress, fillMakerTokenAmount,
+            TradeSide.Maker, TransferType.Trade,
+        );
+        await exchangeTradeEmulator.transferFromAsync(
+            signedOrder.takerTokenAddress, senderAddress, signedOrder.maker, fillTakerTokenAmount,
+            TradeSide.Taker, TransferType.Trade,
+        );
+        const makerFeeAmount = OrderValidationUtils.getPartialAmount(
+            fillTakerTokenAmount,
+            signedOrder.takerTokenAmount,
+            signedOrder.makerFee,
+        );
+        await exchangeTradeEmulator.transferFromAsync(
+            zrxTokenAddress, signedOrder.maker, signedOrder.feeRecipient, makerFeeAmount, TradeSide.Maker,
+            TransferType.Fee,
+        );
+        const takerFeeAmount = OrderValidationUtils.getPartialAmount(
+            fillTakerTokenAmount,
+            signedOrder.takerTokenAmount,
+            signedOrder.takerFee,
+        );
+        await exchangeTradeEmulator.transferFromAsync(
+            zrxTokenAddress, senderAddress, signedOrder.feeRecipient, takerFeeAmount, TradeSide.Taker,
+            TransferType.Fee,
+        );
+    }
+    private static validateRemainingFillAmountNotZeroOrThrow(
+        takerTokenAmount: BigNumber, unavailableTakerTokenAmount: BigNumber,
+    ) {
+        if (takerTokenAmount.eq(unavailableTakerTokenAmount)) {
+            throw new Error(ExchangeContractErrs.OrderRemainingFillAmountZero);
+        }
+    }
+    private static validateOrderNotExpiredOrThrow(expirationUnixTimestampSec: BigNumber) {
+        const currentUnixTimestampSec = utils.getCurrentUnixTimestampSec();
+        if (expirationUnixTimestampSec.lessThan(currentUnixTimestampSec)) {
+            throw new Error(ExchangeContractErrs.OrderFillExpired);
+        }
+    }
+    private static getPartialAmount(numerator: BigNumber, denominator: BigNumber,
+                                    target: BigNumber): BigNumber {
+        const fillMakerTokenAmount = numerator
+                                     .mul(target)
+                                     .div(denominator)
+                                     .round(0);
+        return fillMakerTokenAmount;
+    }
+    constructor(tokenWrapper: TokenWrapper, exchangeWrapper: ExchangeWrapper) {
+        this.tokenWrapper = tokenWrapper;
+        this.exchangeWrapper = exchangeWrapper;
+    }
+    public async validateOrderFillableOrThrowAsync(
+        exchangeTradeEmulator: ExchangeTransferSimulator, signedOrder: SignedOrder, zrxTokenAddress: string,
+        expectedFillTakerTokenAmount?: BigNumber): Promise<void> {
+        const orderHash = utils.getOrderHashHex(signedOrder);
+        const unavailableTakerTokenAmount = await this.exchangeWrapper.getUnavailableTakerAmountAsync(orderHash);
+        OrderValidationUtils.validateRemainingFillAmountNotZeroOrThrow(
+            signedOrder.takerTokenAmount, unavailableTakerTokenAmount,
+        );
+        OrderValidationUtils.validateOrderNotExpiredOrThrow(signedOrder.expirationUnixTimestampSec);
+        let fillTakerTokenAmount = signedOrder.takerTokenAmount.minus(unavailableTakerTokenAmount);
+        if (!_.isUndefined(expectedFillTakerTokenAmount)) {
+            fillTakerTokenAmount = expectedFillTakerTokenAmount;
+        }
+        const fillMakerTokenAmount = OrderValidationUtils.getPartialAmount(
+            fillTakerTokenAmount,
+            signedOrder.takerTokenAmount,
+            signedOrder.makerTokenAmount,
+        );
+        await exchangeTradeEmulator.transferFromAsync(
+            signedOrder.makerTokenAddress, signedOrder.maker, signedOrder.taker, fillMakerTokenAmount,
+            TradeSide.Maker, TransferType.Trade,
+        );
+        const makerFeeAmount = OrderValidationUtils.getPartialAmount(
+            fillTakerTokenAmount,
+            signedOrder.takerTokenAmount,
+            signedOrder.makerFee,
+        );
+        await exchangeTradeEmulator.transferFromAsync(
+            zrxTokenAddress, signedOrder.maker, signedOrder.feeRecipient, makerFeeAmount,
+            TradeSide.Maker, TransferType.Fee,
+        );
+    }
+    public async validateFillOrderThrowIfInvalidAsync(
+        exchangeTradeEmulator: ExchangeTransferSimulator, signedOrder: SignedOrder,
+        fillTakerTokenAmount: BigNumber, takerAddress: string,
+        zrxTokenAddress: string): Promise<BigNumber> {
+        if (fillTakerTokenAmount.eq(0)) {
+            throw new Error(ExchangeContractErrs.OrderFillAmountZero);
+        }
+        const orderHash = utils.getOrderHashHex(signedOrder);
+        if (!ZeroEx.isValidSignature(orderHash, signedOrder.ecSignature, signedOrder.maker)) {
+            throw new Error(ZeroExError.InvalidSignature);
+        }
+        const unavailableTakerTokenAmount = await this.exchangeWrapper.getUnavailableTakerAmountAsync(orderHash);
+        OrderValidationUtils.validateRemainingFillAmountNotZeroOrThrow(
+            signedOrder.takerTokenAmount, unavailableTakerTokenAmount,
+        );
+        if (signedOrder.taker !== constants.NULL_ADDRESS && signedOrder.taker !== takerAddress) {
+            throw new Error(ExchangeContractErrs.TransactionSenderIsNotFillOrderTaker);
+        }
+        OrderValidationUtils.validateOrderNotExpiredOrThrow(signedOrder.expirationUnixTimestampSec);
+        const remainingTakerTokenAmount = signedOrder.takerTokenAmount.minus(unavailableTakerTokenAmount);
+        const filledTakerTokenAmount = remainingTakerTokenAmount.lessThan(fillTakerTokenAmount) ?
+                                       remainingTakerTokenAmount :
+                                       fillTakerTokenAmount;
+        await OrderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+            exchangeTradeEmulator, signedOrder, filledTakerTokenAmount, takerAddress, zrxTokenAddress,
+        );
+
+        const wouldRoundingErrorOccur = await this.exchangeWrapper.isRoundingErrorAsync(
+            filledTakerTokenAmount, signedOrder.takerTokenAmount, signedOrder.makerTokenAmount,
+        );
+        if (wouldRoundingErrorOccur) {
+            throw new Error(ExchangeContractErrs.OrderFillRoundingError);
+        }
+        return filledTakerTokenAmount;
+    }
+    public async validateFillOrKillOrderThrowIfInvalidAsync(
+        exchangeTradeEmulator: ExchangeTransferSimulator, signedOrder: SignedOrder,
+        fillTakerTokenAmount: BigNumber, takerAddress: string, zrxTokenAddress: string): Promise<void> {
+        const filledTakerTokenAmount = await this.validateFillOrderThrowIfInvalidAsync(
+            exchangeTradeEmulator, signedOrder, fillTakerTokenAmount, takerAddress, zrxTokenAddress,
+        );
+        if (filledTakerTokenAmount !== fillTakerTokenAmount) {
+            throw new Error(ExchangeContractErrs.InsufficientRemainingFillAmount);
+        }
+    }
+}

packages/0x.js/src/utils/signature_utils.ts

@@ -1,7 +1,23 @@
 import * as ethUtil from 'ethereumjs-util';
+
 import {ECSignature} from '../types';
 
 export const signatureUtils = {
+    isValidSignature(data: string, signature: ECSignature, signerAddress: string): boolean {
+        const dataBuff = ethUtil.toBuffer(data);
+        const msgHashBuff = ethUtil.hashPersonalMessage(dataBuff);
+        try {
+            const pubKey = ethUtil.ecrecover(
+                msgHashBuff,
+                signature.v,
+                ethUtil.toBuffer(signature.r),
+                ethUtil.toBuffer(signature.s));
+            const retrievedAddress = ethUtil.bufferToHex(ethUtil.pubToAddress(pubKey));
+            return retrievedAddress === signerAddress;
+        } catch (err) {
+            return false;
+        }
+    },
     parseSignatureHexAsVRS(signatureHex: string): ECSignature {
         const signatureBuffer = ethUtil.toBuffer(signatureHex);
         let v = signatureBuffer[0];

packages/0x.js/src/utils/utils.ts

@@ -1,9 +1,10 @@
-import * as _ from 'lodash';
+import BigNumber from 'bignumber.js';
+import BN = require('bn.js');
 import * as ethABI from 'ethereumjs-abi';
 import * as ethUtil from 'ethereumjs-util';
+import * as _ from 'lodash';
+
 import {Order, SignedOrder, SolidityTypes} from '../types';
-import * as BigNumber from 'bignumber.js';
-import BN = require('bn.js');
 
 export const utils = {
     /**
@@ -12,7 +13,7 @@ export const utils = {
      * expects values of Solidity type `uint` to be passed as type `BN`.
      * We do not use BN anywhere else in the codebase.
      */
-    bigNumberToBN(value: BigNumber.BigNumber) {
+    bigNumberToBN(value: BigNumber) {
         return new BN(value.toString(), 10);
     },
     consoleLog(message: string): void {
@@ -49,7 +50,10 @@ export const utils = {
         const hashHex = ethUtil.bufferToHex(hashBuff);
         return hashHex;
     },
-    getCurrentUnixTimestamp(): BigNumber.BigNumber {
-        return new BigNumber(Date.now() / 1000);
+    getCurrentUnixTimestampSec(): BigNumber {
+        return new BigNumber(Date.now() / 1000).round();
+    },
+    getCurrentUnixTimestampMs(): BigNumber {
+        return new BigNumber(Date.now());
     },
 };

packages/0x.js/src/web3_wrapper.ts

@@ -0,0 +1,200 @@
+import BigNumber from 'bignumber.js';
+import promisify = require('es6-promisify');
+import * as _ from 'lodash';
+import * as Web3 from 'web3';
+
+import {Contract} from './contract';
+import {Artifact, ArtifactContractName, TransactionReceipt, ZeroExError} from './types';
+
+interface RawLogEntry {
+    logIndex: string|null;
+    transactionIndex: string|null;
+    transactionHash: string;
+    blockHash: string|null;
+    blockNumber: string|null;
+    address: string;
+    data: string;
+    topics: string[];
+}
+
+const CONTRACT_NAME_TO_NOT_FOUND_ERROR: {[contractName: string]: ZeroExError} = {
+    ZRX: ZeroExError.ZRXContractDoesNotExist,
+    EtherToken: ZeroExError.EtherTokenContractDoesNotExist,
+    Token: ZeroExError.TokenContractDoesNotExist,
+    TokenRegistry: ZeroExError.TokenRegistryContractDoesNotExist,
+    TokenTransferProxy: ZeroExError.TokenTransferProxyContractDoesNotExist,
+    Exchange: ZeroExError.ExchangeContractDoesNotExist,
+};
+
+export class Web3Wrapper {
+    private web3: Web3;
+    private networkId: number;
+    private defaults: Partial<Web3.TxData>;
+    private jsonRpcRequestId: number;
+    constructor(provider: Web3.Provider, networkId: number, defaults?: Partial<Web3.TxData>) {
+        if (_.isUndefined((provider as any).sendAsync)) {
+            // Web3@1.0 provider doesn't support synchronous http requests,
+            // so it only has an async `send` method, instead of a `send` and `sendAsync` in web3@0.x.x`
+            // We re-assign the send method so that Web3@1.0 providers work with 0x.js
+            (provider as any).sendAsync = (provider as any).send;
+        }
+        this.web3 = new Web3();
+        this.networkId = networkId;
+        this.web3.setProvider(provider);
+        this.defaults = defaults || {};
+        this.jsonRpcRequestId = 0;
+    }
+    public setProvider(provider: Web3.Provider, networkId: number) {
+        this.networkId = networkId;
+        this.web3.setProvider(provider);
+    }
+    public isAddress(address: string): boolean {
+        return this.web3.isAddress(address);
+    }
+    public async isSenderAddressAvailableAsync(senderAddress: string): Promise<boolean> {
+        const addresses = await this.getAvailableAddressesAsync();
+        return _.includes(addresses, senderAddress);
+    }
+    public async getNodeVersionAsync(): Promise<string> {
+        const nodeVersion = await promisify(this.web3.version.getNode)();
+        return nodeVersion;
+    }
+    public async getTransactionReceiptAsync(txHash: string): Promise<TransactionReceipt> {
+        const transactionReceipt = await promisify(this.web3.eth.getTransactionReceipt)(txHash);
+        if (!_.isNull(transactionReceipt)) {
+            transactionReceipt.status = this.normalizeTxReceiptStatus(transactionReceipt.status);
+        }
+        return transactionReceipt;
+    }
+    public getCurrentProvider(): Web3.Provider {
+        return this.web3.currentProvider;
+    }
+    public getNetworkId(): number {
+        return this.networkId;
+    }
+    public async getContractInstanceFromArtifactAsync<A extends Web3.ContractInstance>(artifact: Artifact,
+                                                                                       address?: string): Promise<A> {
+        let contractAddress: string;
+        if (_.isUndefined(address)) {
+            const networkId = this.getNetworkId();
+            if (_.isUndefined(artifact.networks[networkId])) {
+                throw new Error(ZeroExError.ContractNotDeployedOnNetwork);
+            }
+            contractAddress = artifact.networks[networkId].address.toLowerCase();
+        } else {
+            contractAddress = address;
+        }
+        const doesContractExist = await this.doesContractExistAtAddressAsync(contractAddress);
+        if (!doesContractExist) {
+            throw new Error(CONTRACT_NAME_TO_NOT_FOUND_ERROR[artifact.contract_name]);
+        }
+        const contractInstance = this.getContractInstance<A>(
+            artifact.abi, contractAddress,
+        );
+        return contractInstance;
+    }
+    public toWei(ethAmount: BigNumber): BigNumber {
+        const balanceWei = this.web3.toWei(ethAmount, 'ether');
+        return balanceWei;
+    }
+    public async getBalanceInWeiAsync(owner: string): Promise<BigNumber> {
+        let balanceInWei = await promisify(this.web3.eth.getBalance)(owner);
+        balanceInWei = new BigNumber(balanceInWei);
+        return balanceInWei;
+    }
+    public async doesContractExistAtAddressAsync(address: string): Promise<boolean> {
+        const code = await promisify(this.web3.eth.getCode)(address);
+        // Regex matches 0x0, 0x00, 0x in order to accommodate poorly implemented clients
+        const codeIsEmpty = /^0x0{0,40}$/i.test(code);
+        return !codeIsEmpty;
+    }
+    public async signTransactionAsync(address: string, message: string): Promise<string> {
+        const signData = await promisify(this.web3.eth.sign)(address, message);
+        return signData;
+    }
+    public async getBlockNumberAsync(): Promise<number> {
+        const blockNumber = await promisify(this.web3.eth.getBlockNumber)();
+        return blockNumber;
+    }
+    public async getBlockAsync(blockParam: string|Web3.BlockParam): Promise<Web3.BlockWithoutTransactionData> {
+        const block = await promisify(this.web3.eth.getBlock)(blockParam);
+        return block;
+    }
+    public async getBlockTimestampAsync(blockParam: string|Web3.BlockParam): Promise<number> {
+        const {timestamp} = await this.getBlockAsync(blockParam);
+        return timestamp;
+    }
+    public async getAvailableAddressesAsync(): Promise<string[]> {
+        const addresses: string[] = await promisify(this.web3.eth.getAccounts)();
+        return addresses;
+    }
+    public async getLogsAsync(filter: Web3.FilterObject): Promise<Web3.LogEntry[]> {
+        let fromBlock = filter.fromBlock;
+        if (_.isNumber(fromBlock)) {
+            fromBlock = this.web3.toHex(fromBlock);
+        }
+        let toBlock = filter.toBlock;
+        if (_.isNumber(toBlock)) {
+            toBlock = this.web3.toHex(toBlock);
+        }
+        const serializedFilter = {
+            ...filter,
+            fromBlock,
+            toBlock,
+        };
+        const payload = {
+            jsonrpc: '2.0',
+            id: this.jsonRpcRequestId++,
+            method: 'eth_getLogs',
+            params: [serializedFilter],
+        };
+        const rawLogs = await this.sendRawPayloadAsync<RawLogEntry[]>(payload);
+        const formattedLogs = _.map(rawLogs, this.formatLog.bind(this));
+        return formattedLogs;
+    }
+    private getContractInstance<A extends Web3.ContractInstance>(abi: Web3.ContractAbi, address: string): A {
+        const web3ContractInstance = this.web3.eth.contract(abi).at(address);
+        const contractInstance = new Contract(web3ContractInstance, this.defaults) as any as A;
+        return contractInstance;
+    }
+    private async getNetworkAsync(): Promise<number> {
+        const networkId = await promisify(this.web3.version.getNetwork)();
+        return networkId;
+    }
+    private async sendRawPayloadAsync<A>(payload: Web3.JSONRPCRequestPayload): Promise<A> {
+        const sendAsync = this.web3.currentProvider.sendAsync.bind(this.web3.currentProvider);
+        const response = await promisify(sendAsync)(payload);
+        const result = response.result;
+        return result;
+    }
+    private normalizeTxReceiptStatus(status: undefined|null|string|0|1): null|0|1 {
+        // Transaction status might have four values
+        // undefined - Testrpc and other old clients
+        // null - New clients on old transactions
+        // number - Parity
+        // hex - Geth
+        if (_.isString(status)) {
+            return this.web3.toDecimal(status) as 0|1;
+        } else if (_.isUndefined(status)) {
+            return null;
+        } else {
+            return status;
+        }
+    }
+    private formatLog(rawLog: RawLogEntry): Web3.LogEntry {
+        const formattedLog = {
+            ...rawLog,
+            logIndex: this.hexToDecimal(rawLog.logIndex),
+            blockNumber: this.hexToDecimal(rawLog.blockNumber),
+            transactionIndex: this.hexToDecimal(rawLog.transactionIndex),
+        };
+        return formattedLog;
+    }
+    private hexToDecimal(hex: string|null): number|null {
+        if (_.isNull(hex)) {
+            return null;
+        }
+        const decimal = this.web3.toDecimal(hex);
+        return decimal;
+    }
+}

packages/0x.js/test/0x.js_test.ts

@@ -1,14 +1,16 @@
-import * as _ from 'lodash';
+import BigNumber from 'bignumber.js';
 import * as chai from 'chai';
-import {chaiSetup} from './utils/chai_setup';
+import * as _ from 'lodash';
 import 'mocha';
-import * as BigNumber from 'bignumber.js';
 import * as Sinon from 'sinon';
-import {ZeroEx, Order, ZeroExError, LogWithDecodedArgs} from '../src';
+
+import {ApprovalContractEventArgs, LogWithDecodedArgs, Order, TokenEvents, ZeroEx, ZeroExError} from '../src';
+
+import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+import {chaiSetup} from './utils/chai_setup';
 import {constants} from './utils/constants';
 import {TokenUtils} from './utils/token_utils';
 import {web3Factory} from './utils/web3_factory';
-import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
 
 const blockchainLifecycle = new BlockchainLifecycle();
 chaiSetup.configure();
@@ -16,7 +18,10 @@ const expect = chai.expect;
 
 describe('ZeroEx library', () => {
     const web3 = web3Factory.create();
-    const zeroEx = new ZeroEx(web3.currentProvider);
+    const config = {
+        networkId: constants.TESTRPC_NETWORK_ID,
+    };
+    const zeroEx = new ZeroEx(web3.currentProvider, config);
     describe('#setProvider', () => {
         it('overrides provider in nested web3s and invalidates contractInstances', async () => {
             // Instantiate the contract instances with the current provider
@@ -28,7 +33,7 @@ describe('ZeroEx library', () => {
             const newProvider = web3Factory.getRpcProvider();
             // Add property to newProvider so that we can differentiate it from old provider
             (newProvider as any).zeroExTestId = 1;
-            await zeroEx.setProviderAsync(newProvider);
+            zeroEx.setProvider(newProvider, constants.TESTRPC_NETWORK_ID);
 
             // Check that contractInstances with old provider are removed after provider update
             expect((zeroEx.exchange as any)._exchangeContractIfExists).to.be.undefined();
@@ -36,11 +41,11 @@ describe('ZeroEx library', () => {
 
             // Check that all nested web3 wrapper instances return the updated provider
             const nestedWeb3WrapperProvider = (zeroEx as any)._web3Wrapper.getCurrentProvider();
-            expect((nestedWeb3WrapperProvider as any).zeroExTestId).to.be.a('number');
+            expect((nestedWeb3WrapperProvider).zeroExTestId).to.be.a('number');
             const exchangeWeb3WrapperProvider = (zeroEx.exchange as any)._web3Wrapper.getCurrentProvider();
-            expect((exchangeWeb3WrapperProvider as any).zeroExTestId).to.be.a('number');
+            expect((exchangeWeb3WrapperProvider).zeroExTestId).to.be.a('number');
             const tokenRegistryWeb3WrapperProvider = (zeroEx.tokenRegistry as any)._web3Wrapper.getCurrentProvider();
-            expect((tokenRegistryWeb3WrapperProvider as any).zeroExTestId).to.be.a('number');
+            expect((tokenRegistryWeb3WrapperProvider).zeroExTestId).to.be.a('number');
         });
     });
     describe('#isValidSignature', () => {
@@ -220,11 +225,11 @@ describe('ZeroEx library', () => {
             const tokens = await zeroEx.tokenRegistry.getTokensAsync();
             const tokenUtils = new TokenUtils(tokens);
             const zrxTokenAddress = tokenUtils.getProtocolTokenOrThrow().address;
-            const proxyAddress = await zeroEx.proxy.getContractAddressAsync();
+            const proxyAddress = zeroEx.proxy.getContractAddress();
             const txHash = await zeroEx.token.setUnlimitedProxyAllowanceAsync(zrxTokenAddress, coinbase);
             const txReceiptWithDecodedLogs = await zeroEx.awaitTransactionMinedAsync(txHash);
-            const log = txReceiptWithDecodedLogs.logs[0] as LogWithDecodedArgs;
-            expect(log.event).to.be.equal('Approval');
+            const log = txReceiptWithDecodedLogs.logs[0] as LogWithDecodedArgs<ApprovalContractEventArgs>;
+            expect(log.event).to.be.equal(TokenEvents.Approval);
             expect(log.args._owner).to.be.equal(coinbase);
             expect(log.args._spender).to.be.equal(proxyAddress);
             expect(log.args._value).to.be.bignumber.equal(zeroEx.token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS);
@@ -232,28 +237,29 @@ describe('ZeroEx library', () => {
     });
     describe('#config', () => {
         it('allows to specify exchange contract address', async () => {
-            const config = {
+            const zeroExConfig = {
                 exchangeContractAddress: ZeroEx.NULL_ADDRESS,
+                networkId: constants.TESTRPC_NETWORK_ID,
             };
-            const zeroExWithWrongExchangeAddress = new ZeroEx(web3.currentProvider, config);
-            return expect(zeroExWithWrongExchangeAddress.exchange.getContractAddressAsync())
-                .to.be.rejectedWith(ZeroExError.ContractDoesNotExist);
+            const zeroExWithWrongExchangeAddress = new ZeroEx(web3.currentProvider, zeroExConfig);
+            expect(zeroExWithWrongExchangeAddress.exchange.getContractAddress()).to.be.equal(ZeroEx.NULL_ADDRESS);
         });
         it('allows to specify ether token contract address', async () => {
-            const config = {
+            const zeroExConfig = {
                 etherTokenContractAddress: ZeroEx.NULL_ADDRESS,
+                networkId: constants.TESTRPC_NETWORK_ID,
             };
-            const zeroExWithWrongEtherTokenAddress = new ZeroEx(web3.currentProvider, config);
-            return expect(zeroExWithWrongEtherTokenAddress.etherToken.getContractAddressAsync())
-                .to.be.rejectedWith(ZeroExError.ContractDoesNotExist);
+            const zeroExWithWrongEtherTokenAddress = new ZeroEx(web3.currentProvider, zeroExConfig);
+            expect(zeroExWithWrongEtherTokenAddress.etherToken.getContractAddress()).to.be.equal(ZeroEx.NULL_ADDRESS);
         });
         it('allows to specify token registry token contract address', async () => {
-            const config = {
+            const zeroExConfig = {
                 tokenRegistryContractAddress: ZeroEx.NULL_ADDRESS,
+                networkId: constants.TESTRPC_NETWORK_ID,
             };
-            const zeroExWithWrongTokenRegistryAddress = new ZeroEx(web3.currentProvider, config);
-            return expect(zeroExWithWrongTokenRegistryAddress.tokenRegistry.getContractAddressAsync())
-                .to.be.rejectedWith(ZeroExError.ContractDoesNotExist);
+            const zeroExWithWrongTokenRegistryAddress = new ZeroEx(web3.currentProvider, zeroExConfig);
+            expect(zeroExWithWrongTokenRegistryAddress.tokenRegistry.getContractAddress())
+                .to.be.equal(ZeroEx.NULL_ADDRESS);
         });
     });
 });

packages/0x.js/test/artifacts_test.ts

@@ -1,8 +1,10 @@
-import * as fs from 'fs';
 import * as chai from 'chai';
-import {chaiSetup} from './utils/chai_setup';
+import * as fs from 'fs';
 import HDWalletProvider = require('truffle-hdwallet-provider');
+
 import {ZeroEx} from '../src';
+
+import {chaiSetup} from './utils/chai_setup';
 import {constants} from './utils/constants';
 
 chaiSetup.configure();
@@ -18,15 +20,18 @@ describe('Artifacts', () => {
         const packageJSON = JSON.parse(packageJSONContent);
         const mnemonic = packageJSON.config.mnemonic;
         const web3Provider = new HDWalletProvider(mnemonic, kovanRpcUrl);
-        const zeroEx = new ZeroEx(web3Provider);
+        const config = {
+            networkId: constants.KOVAN_NETWORK_ID,
+        };
+        const zeroEx = new ZeroEx(web3Provider, config);
         it('token registry contract is deployed', async () => {
             await (zeroEx.tokenRegistry as any)._getTokenRegistryContractAsync();
         }).timeout(TIMEOUT);
         it('proxy contract is deployed', async () => {
-            await (zeroEx.token as any)._getTokenTransferProxyAddressAsync();
+            await (zeroEx.proxy as any)._getTokenTransferProxyContractAsync();
         }).timeout(TIMEOUT);
         it('exchange contract is deployed', async () => {
-            await zeroEx.exchange.getContractAddressAsync();
+            await (zeroEx.exchange as any)._getExchangeContractAsync();
         }).timeout(TIMEOUT);
     });
     describe('contracts are deployed on ropsten', () => {
@@ -35,15 +40,18 @@ describe('Artifacts', () => {
         const packageJSON = JSON.parse(packageJSONContent);
         const mnemonic = packageJSON.config.mnemonic;
         const web3Provider = new HDWalletProvider(mnemonic, ropstenRpcUrl);
-        const zeroEx = new ZeroEx(web3Provider);
+        const config = {
+            networkId: constants.ROPSTEN_NETWORK_ID,
+        };
+        const zeroEx = new ZeroEx(web3Provider, config);
         it('token registry contract is deployed', async () => {
             await (zeroEx.tokenRegistry as any)._getTokenRegistryContractAsync();
         }).timeout(TIMEOUT);
         it('proxy contract is deployed', async () => {
-            await (zeroEx.token as any)._getTokenTransferProxyAddressAsync();
+            await (zeroEx.proxy as any)._getTokenTransferProxyContractAsync();
         }).timeout(TIMEOUT);
         it('exchange contract is deployed', async () => {
-            await zeroEx.exchange.getContractAddressAsync();
+            await (zeroEx.exchange as any)._getExchangeContractAsync();
         }).timeout(TIMEOUT);
     });
 });

packages/0x.js/test/assert_test.ts

@@ -1,14 +1,20 @@
 import * as chai from 'chai';
 import 'mocha';
+
 import {ZeroEx} from '../src';
 import {assert} from '../src/utils/assert';
+
+import {constants} from './utils/constants';
 import {web3Factory} from './utils/web3_factory';
 
 const expect = chai.expect;
 
 describe('Assertion library', () => {
     const web3 = web3Factory.create();
-    const zeroEx = new ZeroEx(web3.currentProvider);
+    const config = {
+        networkId: constants.TESTRPC_NETWORK_ID,
+    };
+    const zeroEx = new ZeroEx(web3.currentProvider, config);
     describe('#isSenderAddressHexAsync', () => {
         it('throws when address is invalid', async () => {
             const address = '0xdeadbeef';

packages/0x.js/test/ether_token_wrapper_test.ts

@@ -1,12 +1,14 @@
-import 'mocha';
+import BigNumber from 'bignumber.js';
 import * as chai from 'chai';
-import {chaiSetup} from './utils/chai_setup';
+import 'mocha';
 import * as Web3 from 'web3';
-import * as BigNumber from 'bignumber.js';
-import promisify = require('es6-promisify');
-import {web3Factory} from './utils/web3_factory';
+
 import {ZeroEx, ZeroExError} from '../src';
+
 import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+import {chaiSetup} from './utils/chai_setup';
+import {constants} from './utils/constants';
+import {web3Factory} from './utils/web3_factory';
 
 chaiSetup.configure();
 const expect = chai.expect;
@@ -16,7 +18,7 @@ const blockchainLifecycle = new BlockchainLifecycle();
 // a small amount of ETH will be used to pay this gas cost. We therefore check that the difference between
 // the expected balance and actual balance (given the amount of ETH deposited), only deviates by the amount
 // required to pay gas costs.
-const MAX_REASONABLE_GAS_COST_IN_WEI = 62237;
+const MAX_REASONABLE_GAS_COST_IN_WEI = 62517;
 
 describe('EtherTokenWrapper', () => {
     let web3: Web3;
@@ -24,18 +26,19 @@ describe('EtherTokenWrapper', () => {
     let userAddresses: string[];
     let addressWithETH: string;
     let wethContractAddress: string;
-    let depositWeiAmount: BigNumber.BigNumber;
+    let depositWeiAmount: BigNumber;
     let decimalPlaces: number;
     const gasPrice = new BigNumber(1);
     const zeroExConfig = {
         gasPrice,
+        networkId: constants.TESTRPC_NETWORK_ID,
     };
     before(async () => {
         web3 = web3Factory.create();
         zeroEx = new ZeroEx(web3.currentProvider, zeroExConfig);
         userAddresses = await zeroEx.getAvailableAddressesAsync();
         addressWithETH = userAddresses[0];
-        wethContractAddress = await zeroEx.etherToken.getContractAddressAsync();
+        wethContractAddress = zeroEx.etherToken.getContractAddress();
         depositWeiAmount = (zeroEx as any)._web3Wrapper.toWei(new BigNumber(5));
         decimalPlaces = 7;
     });

packages/0x.js/test/event_watcher_test.ts

@@ -0,0 +1,130 @@
+import BigNumber from 'bignumber.js';
+import * as chai from 'chai';
+import * as _ from 'lodash';
+import 'mocha';
+import * as Sinon from 'sinon';
+import * as Web3 from 'web3';
+
+import {
+    DecodedLogEvent,
+    LogEvent,
+    ZeroEx,
+} from '../src';
+import {EventWatcher} from '../src/order_watcher/event_watcher';
+import {DoneCallback} from '../src/types';
+import {Web3Wrapper} from '../src/web3_wrapper';
+
+import {chaiSetup} from './utils/chai_setup';
+import {constants} from './utils/constants';
+import {web3Factory} from './utils/web3_factory';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+describe('EventWatcher', () => {
+    let web3: Web3;
+    let stubs: Sinon.SinonStub[] = [];
+    let eventWatcher: EventWatcher;
+    let web3Wrapper: Web3Wrapper;
+    const numConfirmations = 0;
+    const logA: Web3.LogEntry = {
+        address: '0x71d271f8b14adef568f8f28f1587ce7271ac4ca5',
+        blockHash: null,
+        blockNumber: null,
+        data: '',
+        logIndex: null,
+        topics: [],
+        transactionHash: '0x004881d38cd4a8f72f1a0d68c8b9b8124504706041ff37019c1d1ed6bfda8e17',
+        transactionIndex: 0,
+    };
+    const logB: Web3.LogEntry = {
+        address: '0x8d12a197cb00d4747a1fe03395095ce2a5cc6819',
+        blockHash: null,
+        blockNumber: null,
+        data: '',
+        logIndex: null,
+        topics: [ '0xf341246adaac6f497bc2a656f546ab9e182111d630394f0c57c710a59a2cb567' ],
+        transactionHash: '0x01ef3c048b18d9b09ea195b4ed94cf8dd5f3d857a1905ff886b152cfb1166f25',
+        transactionIndex: 0,
+    };
+    const logC: Web3.LogEntry = {
+        address: '0x1d271f8b174adef58f1587ce68f8f27271ac4ca5',
+        blockHash: null,
+        blockNumber: null,
+        data: '',
+        logIndex: null,
+        topics: [ '0xf341246adaac6f497bc2a656f546ab9e182111d630394f0c57c710a59a2cb567' ],
+        transactionHash: '0x01ef3c048b18d9b09ea195b4ed94cf8dd5f3d857a1905ff886b152cfb1166f25',
+        transactionIndex: 0,
+    };
+    before(async () => {
+        web3 = web3Factory.create();
+        const pollingIntervalMs = 10;
+        web3Wrapper = new Web3Wrapper(web3.currentProvider, constants.TESTRPC_NETWORK_ID);
+        eventWatcher = new EventWatcher(web3Wrapper, pollingIntervalMs);
+    });
+    afterEach(() => {
+        // clean up any stubs after the test has completed
+        _.each(stubs, s => s.restore());
+        stubs = [];
+        eventWatcher.unsubscribe();
+    });
+    it('correctly emits initial log events', (done: DoneCallback) => {
+        const logs: Web3.LogEntry[] = [logA, logB];
+        const expectedLogEvents = [
+            {
+                removed: false,
+                ...logA,
+            },
+            {
+                removed: false,
+                ...logB,
+            },
+        ];
+        const getLogsStub = Sinon.stub(web3Wrapper, 'getLogsAsync');
+        getLogsStub.onCall(0).returns(logs);
+        stubs.push(getLogsStub);
+        const callback = (event: LogEvent) => {
+            const expectedLogEvent = expectedLogEvents.shift();
+            expect(event).to.be.deep.equal(expectedLogEvent);
+            if (_.isEmpty(expectedLogEvents)) {
+                done();
+            }
+        };
+        eventWatcher.subscribe(callback);
+    });
+    it('correctly computes the difference and emits only changes', (done: DoneCallback) => {
+        const initialLogs: Web3.LogEntry[] = [logA, logB];
+        const changedLogs: Web3.LogEntry[] = [logA, logC];
+        const expectedLogEvents = [
+            {
+                removed: false,
+                ...logA,
+            },
+            {
+                removed: false,
+                ...logB,
+            },
+            {
+                removed: true,
+                ...logB,
+            },
+            {
+                removed: false,
+                ...logC,
+            },
+        ];
+        const getLogsStub = Sinon.stub(web3Wrapper, 'getLogsAsync');
+        getLogsStub.onCall(0).returns(initialLogs);
+        getLogsStub.onCall(1).returns(changedLogs);
+        stubs.push(getLogsStub);
+        const callback = (event: LogEvent) => {
+            const expectedLogEvent = expectedLogEvents.shift();
+            expect(event).to.be.deep.equal(expectedLogEvent);
+            if (_.isEmpty(expectedLogEvents)) {
+                done();
+            }
+        };
+        eventWatcher.subscribe(callback);
+    });
+});

packages/0x.js/test/exchange_transfer_simulator_test.ts

@@ -0,0 +1,93 @@
+import BigNumber from 'bignumber.js';
+import * as chai from 'chai';
+
+import {ExchangeContractErrs, Token, ZeroEx} from '../src';
+import {BlockParamLiteral, TradeSide, TransferType} from '../src/types';
+import {ExchangeTransferSimulator} from '../src/utils/exchange_transfer_simulator';
+
+import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+import {chaiSetup} from './utils/chai_setup';
+import {constants} from './utils/constants';
+import {web3Factory} from './utils/web3_factory';
+
+chaiSetup.configure();
+const expect = chai.expect;
+const blockchainLifecycle = new BlockchainLifecycle();
+
+describe('ExchangeTransferSimulator', () => {
+    const web3 = web3Factory.create();
+    const config = {
+        networkId: constants.TESTRPC_NETWORK_ID,
+    };
+    const zeroEx = new ZeroEx(web3.currentProvider, config);
+    const transferAmount = new BigNumber(5);
+    let userAddresses: string[];
+    let tokens: Token[];
+    let coinbase: string;
+    let sender: string;
+    let recipient: string;
+    let exampleTokenAddress: string;
+    let exchangeTransferSimulator: ExchangeTransferSimulator;
+    let txHash: string;
+    before(async () => {
+        userAddresses = await zeroEx.getAvailableAddressesAsync();
+        [coinbase, sender, recipient] = userAddresses;
+        tokens = await zeroEx.tokenRegistry.getTokensAsync();
+        exampleTokenAddress = tokens[0].address;
+    });
+    beforeEach(async () => {
+        await blockchainLifecycle.startAsync();
+    });
+    afterEach(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    describe('#transferFromAsync', () => {
+        beforeEach(() => {
+            exchangeTransferSimulator = new ExchangeTransferSimulator(zeroEx.token, BlockParamLiteral.Latest);
+        });
+        it('throws if the user doesn\'t have enough allowance', async () => {
+            return expect(exchangeTransferSimulator.transferFromAsync(
+                exampleTokenAddress, sender, recipient, transferAmount, TradeSide.Taker, TransferType.Trade,
+            )).to.be.rejectedWith(ExchangeContractErrs.InsufficientTakerAllowance);
+        });
+        it('throws if the user doesn\'t have enough balance', async () => {
+            txHash = await zeroEx.token.setProxyAllowanceAsync(exampleTokenAddress, sender, transferAmount);
+            await zeroEx.awaitTransactionMinedAsync(txHash);
+            return expect(exchangeTransferSimulator.transferFromAsync(
+                exampleTokenAddress, sender, recipient, transferAmount, TradeSide.Maker, TransferType.Trade,
+            )).to.be.rejectedWith(ExchangeContractErrs.InsufficientMakerBalance);
+        });
+        it('updates balances and proxyAllowance after transfer', async () => {
+            txHash = await zeroEx.token.transferAsync(exampleTokenAddress, coinbase, sender, transferAmount);
+            await zeroEx.awaitTransactionMinedAsync(txHash);
+            txHash = await zeroEx.token.setProxyAllowanceAsync(exampleTokenAddress, sender, transferAmount);
+            await zeroEx.awaitTransactionMinedAsync(txHash);
+            await exchangeTransferSimulator.transferFromAsync(
+                exampleTokenAddress, sender, recipient, transferAmount, TradeSide.Taker, TransferType.Trade,
+            );
+            const store = (exchangeTransferSimulator as any).store;
+            const senderBalance = await store.getBalanceAsync(exampleTokenAddress, sender);
+            const recipientBalance = await store.getBalanceAsync(exampleTokenAddress, recipient);
+            const senderProxyAllowance = await store.getProxyAllowanceAsync(exampleTokenAddress, sender);
+            expect(senderBalance).to.be.bignumber.equal(0);
+            expect(recipientBalance).to.be.bignumber.equal(transferAmount);
+            expect(senderProxyAllowance).to.be.bignumber.equal(0);
+        });
+        it('doesn\'t update proxyAllowance after transfer if unlimited', async () => {
+            txHash = await zeroEx.token.transferAsync(exampleTokenAddress, coinbase, sender, transferAmount);
+            await zeroEx.awaitTransactionMinedAsync(txHash);
+            txHash = await zeroEx.token.setUnlimitedProxyAllowanceAsync(exampleTokenAddress, sender);
+            await zeroEx.awaitTransactionMinedAsync(txHash);
+            await exchangeTransferSimulator.transferFromAsync(
+                exampleTokenAddress, sender, recipient, transferAmount, TradeSide.Taker, TransferType.Trade,
+            );
+            const store = (exchangeTransferSimulator as any).store;
+            const senderBalance = await store.getBalanceAsync(exampleTokenAddress, sender);
+            const recipientBalance = await store.getBalanceAsync(exampleTokenAddress, recipient);
+            const senderProxyAllowance = await store.getProxyAllowanceAsync(exampleTokenAddress, sender);
+            expect(senderBalance).to.be.bignumber.equal(0);
+            expect(recipientBalance).to.be.bignumber.equal(transferAmount);
+            expect(senderProxyAllowance).to.be.bignumber.equal(zeroEx.token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS);
+        });
+    });
+});

packages/0x.js/test/exchange_wrapper_test.ts

@@ -1,30 +1,30 @@
-import 'mocha';
+import BigNumber from 'bignumber.js';
 import * as chai from 'chai';
+import 'mocha';
 import * as Web3 from 'web3';
-import * as BigNumber from 'bignumber.js';
-import {chaiSetup} from './utils/chai_setup';
-import ChaiBigNumber = require('chai-bignumber');
-import promisify = require('es6-promisify');
-import {web3Factory} from './utils/web3_factory';
-import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+
 import {
-    ZeroEx,
-    Token,
-    SignedOrder,
-    SubscriptionOpts,
-    ExchangeEvents,
-    ContractEvent,
+    DecodedLogEvent,
     ExchangeContractErrs,
+    ExchangeEvents,
+    LogCancelContractEventArgs,
+    LogEvent,
+    LogFillContractEventArgs,
     OrderCancellationRequest,
     OrderFillRequest,
-    LogFillContractEventArgs,
-    OrderFillOrKillRequest,
+    SignedOrder,
+    SubscriptionOpts,
+    Token,
+    ZeroEx,
 } from '../src';
-import {DoneCallback} from '../src/types';
+import {BlockParamLiteral, DoneCallback} from '../src/types';
+
+import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+import {chaiSetup} from './utils/chai_setup';
+import {constants} from './utils/constants';
 import {FillScenarios} from './utils/fill_scenarios';
 import {TokenUtils} from './utils/token_utils';
-import {assert} from '../src/utils/assert';
-import {TokenTransferProxyWrapper} from '../src/contract_wrappers/token_transfer_proxy_wrapper';
+import {web3Factory} from './utils/web3_factory';
 
 chaiSetup.configure();
 const expect = chai.expect;
@@ -41,10 +41,13 @@ describe('ExchangeWrapper', () => {
     let zrxTokenAddress: string;
     let fillScenarios: FillScenarios;
     let exchangeContractAddress: string;
+    const config = {
+        networkId: constants.TESTRPC_NETWORK_ID,
+    };
     before(async () => {
         web3 = web3Factory.create();
-        zeroEx = new ZeroEx(web3.currentProvider);
-        exchangeContractAddress = await zeroEx.exchange.getContractAddressAsync();
+        zeroEx = new ZeroEx(web3.currentProvider, config);
+        exchangeContractAddress = zeroEx.exchange.getContractAddress();
         userAddresses = await zeroEx.getAvailableAddressesAsync();
         tokens = await zeroEx.tokenRegistry.getTokensAsync();
         tokenUtils = new TokenUtils(tokens);
@@ -64,7 +67,7 @@ describe('ExchangeWrapper', () => {
         let makerAddress: string;
         let takerAddress: string;
         let feeRecipient: string;
-        const fillTakerAmount = new BigNumber(5);
+        const takerTokenFillAmount = new BigNumber(5);
         before(async () => {
             [coinbase, makerAddress, takerAddress, feeRecipient] = userAddresses;
             tokens = await zeroEx.tokenRegistry.getTokensAsync();
@@ -73,7 +76,7 @@ describe('ExchangeWrapper', () => {
             takerTokenAddress = takerToken.address;
         });
         describe('#batchFillOrKillAsync', () => {
-            it('successfuly batch fillOrKill', async () => {
+            it('successfully batch fillOrKill', async () => {
                 const fillableAmount = new BigNumber(5);
                 const partialFillTakerAmount = new BigNumber(2);
                 const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
@@ -82,44 +85,44 @@ describe('ExchangeWrapper', () => {
                 const anotherSignedOrder = await fillScenarios.createFillableSignedOrderAsync(
                     makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
                 );
-                const orderFillOrKillRequests = [
+                const orderFillRequests = [
                     {
                         signedOrder,
-                        fillTakerAmount: partialFillTakerAmount,
+                        takerTokenFillAmount: partialFillTakerAmount,
                     },
                     {
                         signedOrder: anotherSignedOrder,
-                        fillTakerAmount: partialFillTakerAmount,
+                        takerTokenFillAmount: partialFillTakerAmount,
                     },
                 ];
-                await zeroEx.exchange.batchFillOrKillAsync(orderFillOrKillRequests, takerAddress);
+                await zeroEx.exchange.batchFillOrKillAsync(orderFillRequests, takerAddress);
             });
             describe('order transaction options', () => {
                 let signedOrder: SignedOrder;
-                let orderFillOrKillRequests: OrderFillOrKillRequest[];
+                let orderFillRequests: OrderFillRequest[];
                 const fillableAmount = new BigNumber(5);
                 beforeEach(async () => {
                     signedOrder = await fillScenarios.createFillableSignedOrderAsync(
                         makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
                     );
-                    orderFillOrKillRequests = [
+                    orderFillRequests = [
                         {
                             signedOrder,
-                            fillTakerAmount: new BigNumber(0),
+                            takerTokenFillAmount: new BigNumber(0),
                         },
                     ];
                 });
                 it('should validate when orderTransactionOptions are not present', async () => {
-                    return expect(zeroEx.exchange.batchFillOrKillAsync(orderFillOrKillRequests, takerAddress))
+                    return expect(zeroEx.exchange.batchFillOrKillAsync(orderFillRequests, takerAddress))
                         .to.be.rejectedWith(ExchangeContractErrs.OrderFillAmountZero);
                 });
                 it('should validate when orderTransactionOptions specify to validate', async () => {
-                    return expect(zeroEx.exchange.batchFillOrKillAsync(orderFillOrKillRequests, takerAddress, {
+                    return expect(zeroEx.exchange.batchFillOrKillAsync(orderFillRequests, takerAddress, {
                         shouldValidate: true,
                     })).to.be.rejectedWith(ExchangeContractErrs.OrderFillAmountZero);
                 });
                 it('should not validate when orderTransactionOptions specify not to validate', async () => {
-                    return expect(zeroEx.exchange.batchFillOrKillAsync(orderFillOrKillRequests, takerAddress, {
+                    return expect(zeroEx.exchange.batchFillOrKillAsync(orderFillRequests, takerAddress, {
                         shouldValidate: false,
                     })).to.not.be.rejectedWith(ExchangeContractErrs.OrderFillAmountZero);
                 });
@@ -143,15 +146,15 @@ describe('ExchangeWrapper', () => {
                         .to.be.bignumber.equal(0);
                     expect(await zeroEx.token.getBalanceAsync(takerTokenAddress, takerAddress))
                         .to.be.bignumber.equal(fillableAmount);
-                    await zeroEx.exchange.fillOrKillOrderAsync(signedOrder, fillTakerAmount, takerAddress);
+                    await zeroEx.exchange.fillOrKillOrderAsync(signedOrder, takerTokenFillAmount, takerAddress);
                     expect(await zeroEx.token.getBalanceAsync(makerTokenAddress, makerAddress))
-                        .to.be.bignumber.equal(fillableAmount.minus(fillTakerAmount));
+                        .to.be.bignumber.equal(fillableAmount.minus(takerTokenFillAmount));
                     expect(await zeroEx.token.getBalanceAsync(takerTokenAddress, makerAddress))
-                        .to.be.bignumber.equal(fillTakerAmount);
+                        .to.be.bignumber.equal(takerTokenFillAmount);
                     expect(await zeroEx.token.getBalanceAsync(makerTokenAddress, takerAddress))
-                        .to.be.bignumber.equal(fillTakerAmount);
+                        .to.be.bignumber.equal(takerTokenFillAmount);
                     expect(await zeroEx.token.getBalanceAsync(takerTokenAddress, takerAddress))
-                        .to.be.bignumber.equal(fillableAmount.minus(fillTakerAmount));
+                        .to.be.bignumber.equal(fillableAmount.minus(takerTokenFillAmount));
                 });
                 it('should partially fill a valid order', async () => {
                     const partialFillAmount = new BigNumber(3);
@@ -193,7 +196,7 @@ describe('ExchangeWrapper', () => {
         let takerAddress: string;
         let feeRecipient: string;
         const fillableAmount = new BigNumber(5);
-        const fillTakerAmount = new BigNumber(5);
+        const takerTokenFillAmount = new BigNumber(5);
         const shouldThrowOnInsufficientBalanceOrAllowance = true;
         before(async () => {
             [coinbase, makerAddress, takerAddress, feeRecipient] = userAddresses;
@@ -217,16 +220,16 @@ describe('ExchangeWrapper', () => {
                     expect(await zeroEx.token.getBalanceAsync(takerTokenAddress, takerAddress))
                         .to.be.bignumber.equal(fillableAmount);
                     const txHash = await zeroEx.exchange.fillOrderAsync(
-                        signedOrder, fillTakerAmount, shouldThrowOnInsufficientBalanceOrAllowance, takerAddress);
+                        signedOrder, takerTokenFillAmount, shouldThrowOnInsufficientBalanceOrAllowance, takerAddress);
                     await zeroEx.awaitTransactionMinedAsync(txHash);
                     expect(await zeroEx.token.getBalanceAsync(makerTokenAddress, makerAddress))
-                        .to.be.bignumber.equal(fillableAmount.minus(fillTakerAmount));
+                        .to.be.bignumber.equal(fillableAmount.minus(takerTokenFillAmount));
                     expect(await zeroEx.token.getBalanceAsync(takerTokenAddress, makerAddress))
-                        .to.be.bignumber.equal(fillTakerAmount);
+                        .to.be.bignumber.equal(takerTokenFillAmount);
                     expect(await zeroEx.token.getBalanceAsync(makerTokenAddress, takerAddress))
-                        .to.be.bignumber.equal(fillTakerAmount);
+                        .to.be.bignumber.equal(takerTokenFillAmount);
                     expect(await zeroEx.token.getBalanceAsync(takerTokenAddress, takerAddress))
-                        .to.be.bignumber.equal(fillableAmount.minus(fillTakerAmount));
+                        .to.be.bignumber.equal(fillableAmount.minus(takerTokenFillAmount));
                 });
                 it('should partially fill the valid order', async () => {
                     const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
@@ -253,7 +256,7 @@ describe('ExchangeWrapper', () => {
                         makerAddress, takerAddress, fillableAmount, feeRecipient,
                     );
                     const txHash = await zeroEx.exchange.fillOrderAsync(
-                        signedOrder, fillTakerAmount, shouldThrowOnInsufficientBalanceOrAllowance, takerAddress);
+                        signedOrder, takerTokenFillAmount, shouldThrowOnInsufficientBalanceOrAllowance, takerAddress);
                     await zeroEx.awaitTransactionMinedAsync(txHash);
                     expect(await zeroEx.token.getBalanceAsync(zrxTokenAddress, feeRecipient))
                         .to.be.bignumber.equal(makerFee.plus(takerFee));
@@ -307,11 +310,11 @@ describe('ExchangeWrapper', () => {
                     orderFillBatch = [
                         {
                             signedOrder,
-                            takerTokenFillAmount: fillTakerAmount,
+                            takerTokenFillAmount,
                         },
                         {
                             signedOrder: anotherSignedOrder,
-                            takerTokenFillAmount: fillTakerAmount,
+                            takerTokenFillAmount,
                         },
                     ];
                 });
@@ -326,8 +329,8 @@ describe('ExchangeWrapper', () => {
                     await zeroEx.awaitTransactionMinedAsync(txHash);
                     const filledAmount = await zeroEx.exchange.getFilledTakerAmountAsync(signedOrderHashHex);
                     const anotherFilledAmount = await zeroEx.exchange.getFilledTakerAmountAsync(anotherOrderHashHex);
-                    expect(filledAmount).to.be.bignumber.equal(fillTakerAmount);
-                    expect(anotherFilledAmount).to.be.bignumber.equal(fillTakerAmount);
+                    expect(filledAmount).to.be.bignumber.equal(takerTokenFillAmount);
+                    expect(anotherFilledAmount).to.be.bignumber.equal(takerTokenFillAmount);
                 });
             });
             describe('order transaction options', () => {
@@ -446,7 +449,7 @@ describe('ExchangeWrapper', () => {
                 it('should cancel an order', async () => {
                     const txHash = await zeroEx.exchange.cancelOrderAsync(signedOrder, cancelAmount);
                     await zeroEx.awaitTransactionMinedAsync(txHash);
-                    const cancelledAmount = await zeroEx.exchange.getCanceledTakerAmountAsync(orderHashHex);
+                    const cancelledAmount = await zeroEx.exchange.getCancelledTakerAmountAsync(orderHashHex);
                     expect(cancelledAmount).to.be.bignumber.equal(cancelAmount);
                 });
             });
@@ -505,8 +508,8 @@ describe('ExchangeWrapper', () => {
             describe('successful batch cancels', () => {
                 it('should cancel a batch of orders', async () => {
                     await zeroEx.exchange.batchCancelOrdersAsync(cancelBatch);
-                    const cancelledAmount = await zeroEx.exchange.getCanceledTakerAmountAsync(orderHashHex);
-                    const anotherCancelledAmount = await zeroEx.exchange.getCanceledTakerAmountAsync(
+                    const cancelledAmount = await zeroEx.exchange.getCancelledTakerAmountAsync(orderHashHex);
+                    const anotherCancelledAmount = await zeroEx.exchange.getCancelledTakerAmountAsync(
                         anotherOrderHashHex,
                     );
                     expect(cancelledAmount).to.be.bignumber.equal(cancelAmount);
@@ -548,8 +551,8 @@ describe('ExchangeWrapper', () => {
         let makerTokenAddress: string;
         let takerTokenAddress: string;
         let takerAddress: string;
-        let fillableAmount: BigNumber.BigNumber;
-        let partialFillAmount: BigNumber.BigNumber;
+        let fillableAmount: BigNumber;
+        let partialFillAmount: BigNumber;
         let signedOrder: SignedOrder;
         let orderHash: string;
         before(() => {
@@ -595,28 +598,28 @@ describe('ExchangeWrapper', () => {
                 expect(filledValueT).to.be.bignumber.equal(partialFillAmount);
             });
         });
-        describe('#getCanceledTakerAmountAsync', () => {
+        describe('#getCancelledTakerAmountAsync', () => {
             it('should throw if passed an invalid orderHash', async () => {
                 const invalidOrderHashHex = '0x123';
-                return expect(zeroEx.exchange.getCanceledTakerAmountAsync(invalidOrderHashHex)).to.be.rejected();
+                return expect(zeroEx.exchange.getCancelledTakerAmountAsync(invalidOrderHashHex)).to.be.rejected();
             });
             it('should return zero if passed a valid but non-existent orderHash', async () => {
-                const cancelledValueT = await zeroEx.exchange.getCanceledTakerAmountAsync(NON_EXISTENT_ORDER_HASH);
+                const cancelledValueT = await zeroEx.exchange.getCancelledTakerAmountAsync(NON_EXISTENT_ORDER_HASH);
                 expect(cancelledValueT).to.be.bignumber.equal(0);
             });
             it('should return the cancelledValueT for a valid and partially filled orderHash', async () => {
-                const cancelledValueT = await zeroEx.exchange.getCanceledTakerAmountAsync(orderHash);
+                const cancelledValueT = await zeroEx.exchange.getCancelledTakerAmountAsync(orderHash);
                 expect(cancelledValueT).to.be.bignumber.equal(0);
             });
             it('should return the cancelledValueT for a valid and cancelled orderHash', async () => {
                 const cancelAmount = fillableAmount.minus(partialFillAmount);
                 await zeroEx.exchange.cancelOrderAsync(signedOrder, cancelAmount);
-                const cancelledValueT = await zeroEx.exchange.getCanceledTakerAmountAsync(orderHash);
+                const cancelledValueT = await zeroEx.exchange.getCancelledTakerAmountAsync(orderHash);
                 expect(cancelledValueT).to.be.bignumber.equal(cancelAmount);
             });
         });
     });
-    describe('#subscribeAsync', () => {
+    describe('#subscribe', () => {
         const indexFilterValues = {};
         const shouldThrowOnInsufficientBalanceOrAllowance = true;
         let makerTokenAddress: string;
@@ -624,13 +627,9 @@ describe('ExchangeWrapper', () => {
         let coinbase: string;
         let takerAddress: string;
         let makerAddress: string;
-        let fillableAmount: BigNumber.BigNumber;
+        let fillableAmount: BigNumber;
         let signedOrder: SignedOrder;
-        const subscriptionOpts: SubscriptionOpts = {
-            fromBlock: 0,
-            toBlock: 'latest',
-        };
-        const fillTakerAmountInBaseUnits = new BigNumber(1);
+        const takerTokenFillAmountInBaseUnits = new BigNumber(1);
         const cancelTakerAmountInBaseUnits = new BigNumber(1);
         before(() => {
             [coinbase, makerAddress, takerAddress] = userAddresses;
@@ -645,102 +644,84 @@ describe('ExchangeWrapper', () => {
             );
         });
         afterEach(async () => {
-            await zeroEx.exchange.stopWatchingAllEventsAsync();
+            zeroEx.exchange.unsubscribeAll();
         });
         // Hack: Mocha does not allow a test to be both async and have a `done` callback
-        // Since we need to await the receipt of the event in the `subscribeAsync` callback,
+        // Since we need to await the receipt of the event in the `subscribe` callback,
         // we do need both. A hack is to make the top-level a sync fn w/ a done callback and then
         // wrap the rest of the test in an async block
         // Source: https://github.com/mochajs/mocha/issues/2407
         it('Should receive the LogFill event when an order is filled', (done: DoneCallback) => {
             (async () => {
-                const zeroExEvent = await zeroEx.exchange.subscribeAsync(
-                    ExchangeEvents.LogFill, subscriptionOpts, indexFilterValues, exchangeContractAddress,
-                );
-                zeroExEvent.watch((err: Error, event: ContractEvent) => {
-                    expect(err).to.be.null();
-                    expect(event).to.not.be.undefined();
-                    expect(event.event).to.be.equal('LogFill');
+
+                const callback = (err: Error, logEvent: DecodedLogEvent<LogFillContractEventArgs>) => {
+                    expect(logEvent.log.event).to.be.equal(ExchangeEvents.LogFill);
                     done();
-                });
+                };
+                zeroEx.exchange.subscribe(
+                    ExchangeEvents.LogFill, indexFilterValues, callback,
+                );
                 await zeroEx.exchange.fillOrderAsync(
-                    signedOrder, fillTakerAmountInBaseUnits, shouldThrowOnInsufficientBalanceOrAllowance, takerAddress,
+                    signedOrder, takerTokenFillAmountInBaseUnits, shouldThrowOnInsufficientBalanceOrAllowance,
+                    takerAddress,
                 );
             })().catch(done);
         });
         it('Should receive the LogCancel event when an order is cancelled', (done: DoneCallback) => {
             (async () => {
-                const zeroExEvent = await zeroEx.exchange.subscribeAsync(
-                    ExchangeEvents.LogCancel, subscriptionOpts, indexFilterValues, exchangeContractAddress,
+
+                const callback = (err: Error, logEvent: DecodedLogEvent<LogCancelContractEventArgs>) => {
+                    expect(logEvent.log.event).to.be.equal(ExchangeEvents.LogCancel);
+                    done();
+                };
+                zeroEx.exchange.subscribe(
+                    ExchangeEvents.LogCancel, indexFilterValues, callback,
                 );
-                zeroExEvent.watch((err: Error, event: ContractEvent) => {
-                        expect(err).to.be.null();
-                        expect(event).to.not.be.undefined();
-                        expect(event.event).to.be.equal('LogCancel');
-                        done();
-                });
                 await zeroEx.exchange.cancelOrderAsync(signedOrder, cancelTakerAmountInBaseUnits);
             })().catch(done);
         });
-        it('Outstanding subscriptions are cancelled when zeroEx.setProviderAsync called', (done: DoneCallback) => {
+        it('Outstanding subscriptions are cancelled when zeroEx.setProvider called', (done: DoneCallback) => {
             (async () => {
-                const eventSubscriptionToBeCancelled = await zeroEx.exchange.subscribeAsync(
-                    ExchangeEvents.LogFill, subscriptionOpts, indexFilterValues, exchangeContractAddress,
-                );
-                eventSubscriptionToBeCancelled.watch((err: Error, event: ContractEvent) => {
+
+                const callbackNeverToBeCalled = (err: Error, logEvent: DecodedLogEvent<LogFillContractEventArgs>) => {
                     done(new Error('Expected this subscription to have been cancelled'));
-                });
+                };
+                zeroEx.exchange.subscribe(
+                    ExchangeEvents.LogFill, indexFilterValues, callbackNeverToBeCalled,
+                );
 
                 const newProvider = web3Factory.getRpcProvider();
-                await zeroEx.setProviderAsync(newProvider);
+                zeroEx.setProvider(newProvider, constants.TESTRPC_NETWORK_ID);
 
-                const eventSubscriptionToStay = await zeroEx.exchange.subscribeAsync(
-                    ExchangeEvents.LogFill, subscriptionOpts, indexFilterValues, exchangeContractAddress,
-                );
-                eventSubscriptionToStay.watch((err: Error, event: ContractEvent) => {
-                    expect(err).to.be.null();
-                    expect(event).to.not.be.undefined();
-                    expect(event.event).to.be.equal('LogFill');
+                const callback = (err: Error, logEvent: DecodedLogEvent<LogFillContractEventArgs>) => {
+                    expect(logEvent.log.event).to.be.equal(ExchangeEvents.LogFill);
                     done();
-                });
+                };
+                zeroEx.exchange.subscribe(
+                    ExchangeEvents.LogFill, indexFilterValues, callback,
+                );
                 await zeroEx.exchange.fillOrderAsync(
-                    signedOrder, fillTakerAmountInBaseUnits, shouldThrowOnInsufficientBalanceOrAllowance, takerAddress,
+                    signedOrder, takerTokenFillAmountInBaseUnits, shouldThrowOnInsufficientBalanceOrAllowance,
+                    takerAddress,
                 );
             })().catch(done);
         });
-        it('Should stop watch for events when stopWatchingAsync called on the eventEmitter', (done: DoneCallback) => {
+        it('Should cancel subscription when unsubscribe called', (done: DoneCallback) => {
             (async () => {
-                const eventSubscriptionToBeStopped = await zeroEx.exchange.subscribeAsync(
-                    ExchangeEvents.LogFill, subscriptionOpts, indexFilterValues, exchangeContractAddress,
+                const callbackNeverToBeCalled = (err: Error, logEvent: DecodedLogEvent<LogFillContractEventArgs>) => {
+                    done(new Error('Expected this subscription to have been cancelled'));
+                };
+                const subscriptionToken = zeroEx.exchange.subscribe(
+                    ExchangeEvents.LogFill, indexFilterValues, callbackNeverToBeCalled,
                 );
-                eventSubscriptionToBeStopped.watch((err: Error, event: ContractEvent) => {
-                    done(new Error('Expected this subscription to have been stopped'));
-                });
-                await eventSubscriptionToBeStopped.stopWatchingAsync();
+                zeroEx.exchange.unsubscribe(subscriptionToken);
                 await zeroEx.exchange.fillOrderAsync(
-                    signedOrder, fillTakerAmountInBaseUnits, shouldThrowOnInsufficientBalanceOrAllowance, takerAddress,
+                    signedOrder, takerTokenFillAmountInBaseUnits, shouldThrowOnInsufficientBalanceOrAllowance,
+                    takerAddress,
                 );
                 done();
             })().catch(done);
         });
-        it('Should wrap all event args BigNumber instances in a newer version of BigNumber', (done: DoneCallback) => {
-            (async () => {
-                const zeroExEvent = await zeroEx.exchange.subscribeAsync(
-                    ExchangeEvents.LogFill, subscriptionOpts, indexFilterValues, exchangeContractAddress,
-                );
-                zeroExEvent.watch((err: Error, event: ContractEvent) => {
-                    const args = event.args as LogFillContractEventArgs;
-                    expect(args.filledMakerTokenAmount.isBigNumber).to.be.true();
-                    expect(args.filledTakerTokenAmount.isBigNumber).to.be.true();
-                    expect(args.paidMakerFee.isBigNumber).to.be.true();
-                    expect(args.paidTakerFee.isBigNumber).to.be.true();
-                    done();
-                });
-                await zeroEx.exchange.fillOrderAsync(
-                    signedOrder, fillTakerAmountInBaseUnits, shouldThrowOnInsufficientBalanceOrAllowance, takerAddress,
-                );
-            })().catch(done);
-        });
     });
     describe('#getOrderHashHexUsingContractCallAsync', () => {
         let makerTokenAddress: string;
@@ -765,8 +746,8 @@ describe('ExchangeWrapper', () => {
         });
     });
     describe('#getZRXTokenAddressAsync', () => {
-        it('gets the same token as is in token registry', async () => {
-            const zrxAddress = await zeroEx.exchange.getZRXTokenAddressAsync();
+        it('gets the same token as is in token registry', () => {
+            const zrxAddress = zeroEx.exchange.getZRXTokenAddress();
             const zrxToken = tokenUtils.getProtocolTokenOrThrow();
             expect(zrxAddress).to.equal(zrxToken.address);
         });
@@ -779,8 +760,8 @@ describe('ExchangeWrapper', () => {
         const fillableAmount = new BigNumber(5);
         const shouldThrowOnInsufficientBalanceOrAllowance = true;
         const subscriptionOpts: SubscriptionOpts = {
-            fromBlock: 'earliest',
-            toBlock: 'latest',
+            fromBlock: 0,
+            toBlock: BlockParamLiteral.Latest,
         };
         let txHash: string;
         before(async () => {
@@ -838,11 +819,12 @@ describe('ExchangeWrapper', () => {
             const indexFilterValues = {
                 maker: differentMakerAddress,
             };
-            const logs = await zeroEx.exchange.getLogsAsync(
+            const logs = await zeroEx.exchange.getLogsAsync<LogFillContractEventArgs>(
                 eventName, subscriptionOpts, indexFilterValues,
             );
             expect(logs).to.have.length(1);
-            expect(logs[0].args.maker).to.be.equal(differentMakerAddress);
+            const args = logs[0].args;
+            expect(args.maker).to.be.equal(differentMakerAddress);
         });
     });
-});
+}); // tslint:disable:max-file-line-count

packages/0x.js/test/expiration_watcher_test.ts

@@ -0,0 +1,144 @@
+import BigNumber from 'bignumber.js';
+import * as chai from 'chai';
+import * as _ from 'lodash';
+import 'mocha';
+import * as Sinon from 'sinon';
+import * as Web3 from 'web3';
+
+import {ZeroEx} from '../src/0x';
+import {ExpirationWatcher} from '../src/order_watcher/expiration_watcher';
+import {DoneCallback, Token} from '../src/types';
+import {constants} from '../src/utils/constants';
+import {utils} from '../src/utils/utils';
+import {Web3Wrapper} from '../src/web3_wrapper';
+
+import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+import {chaiSetup} from './utils/chai_setup';
+import {FillScenarios} from './utils/fill_scenarios';
+import {reportCallbackErrors} from './utils/report_callback_errors';
+import {TokenUtils} from './utils/token_utils';
+import {web3Factory} from './utils/web3_factory';
+
+chaiSetup.configure();
+const expect = chai.expect;
+const blockchainLifecycle = new BlockchainLifecycle();
+
+describe('ExpirationWatcher', () => {
+    let web3: Web3;
+    let zeroEx: ZeroEx;
+    let tokenUtils: TokenUtils;
+    let tokens: Token[];
+    let userAddresses: string[];
+    let zrxTokenAddress: string;
+    let fillScenarios: FillScenarios;
+    let exchangeContractAddress: string;
+    let makerTokenAddress: string;
+    let takerTokenAddress: string;
+    let coinbase: string;
+    let makerAddress: string;
+    let takerAddress: string;
+    let feeRecipient: string;
+    const fillableAmount = new BigNumber(5);
+    let currentUnixTimestampSec: BigNumber;
+    let timer: Sinon.SinonFakeTimers;
+    let expirationWatcher: ExpirationWatcher;
+    before(async () => {
+        web3 = web3Factory.create();
+        const config = {
+            networkId: constants.TESTRPC_NETWORK_ID,
+        };
+        zeroEx = new ZeroEx(web3.currentProvider, config);
+        exchangeContractAddress = zeroEx.exchange.getContractAddress();
+        userAddresses = await zeroEx.getAvailableAddressesAsync();
+        tokens = await zeroEx.tokenRegistry.getTokensAsync();
+        tokenUtils = new TokenUtils(tokens);
+        zrxTokenAddress = tokenUtils.getProtocolTokenOrThrow().address;
+        fillScenarios = new FillScenarios(zeroEx, userAddresses, tokens, zrxTokenAddress, exchangeContractAddress);
+        [coinbase, makerAddress, takerAddress, feeRecipient] = userAddresses;
+        tokens = await zeroEx.tokenRegistry.getTokensAsync();
+        const [makerToken, takerToken] = tokenUtils.getNonProtocolTokens();
+        makerTokenAddress = makerToken.address;
+        takerTokenAddress = takerToken.address;
+    });
+    beforeEach(async () => {
+        await blockchainLifecycle.startAsync();
+        const sinonTimerConfig = {shouldAdvanceTime: true} as any;
+        // This constructor has incorrect types
+        timer = Sinon.useFakeTimers(sinonTimerConfig);
+        currentUnixTimestampSec = utils.getCurrentUnixTimestampSec();
+        expirationWatcher = new ExpirationWatcher();
+    });
+    afterEach(async () => {
+        await blockchainLifecycle.revertAsync();
+        timer.restore();
+        expirationWatcher.unsubscribe();
+    });
+    it('correctly emits events when order expires', (done: DoneCallback) => {
+        (async () => {
+            const orderLifetimeSec = 60;
+            const expirationUnixTimestampSec = currentUnixTimestampSec.plus(orderLifetimeSec);
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+                expirationUnixTimestampSec,
+            );
+            const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+            expirationWatcher.addOrder(orderHash, signedOrder.expirationUnixTimestampSec.times(1000));
+            const callbackAsync = reportCallbackErrors(done)(async (hash: string) => {
+                expect(hash).to.be.equal(orderHash);
+                expect(utils.getCurrentUnixTimestampSec()).to.be.bignumber.gte(expirationUnixTimestampSec);
+                done();
+            });
+            expirationWatcher.subscribe(callbackAsync);
+            timer.tick(orderLifetimeSec * 1000);
+        })().catch(done);
+    });
+    it('doesn\'t emit events before order expires', (done: DoneCallback) => {
+        (async () => {
+            const orderLifetimeSec = 60;
+            const expirationUnixTimestampSec = currentUnixTimestampSec.plus(orderLifetimeSec);
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+                expirationUnixTimestampSec,
+            );
+            const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+            expirationWatcher.addOrder(orderHash, signedOrder.expirationUnixTimestampSec.times(1000));
+            const callbackAsync = reportCallbackErrors(done)(async (hash: string) => {
+                done(new Error('Emitted expiration went before the order actually expired'));
+            });
+            expirationWatcher.subscribe(callbackAsync);
+            const notEnoughTime = orderLifetimeSec - 1;
+            timer.tick(notEnoughTime * 1000);
+            done();
+        })().catch(done);
+    });
+    it('emits events in correct order', (done: DoneCallback) => {
+        (async () => {
+            const order1Lifetime = 60;
+            const order2Lifetime = 120;
+            const order1ExpirationUnixTimestampSec = currentUnixTimestampSec.plus(order1Lifetime);
+            const order2ExpirationUnixTimestampSec = currentUnixTimestampSec.plus(order2Lifetime);
+            const signedOrder1 = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+                order1ExpirationUnixTimestampSec,
+            );
+            const signedOrder2 = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+                order2ExpirationUnixTimestampSec,
+            );
+            const orderHash1 = ZeroEx.getOrderHashHex(signedOrder1);
+            const orderHash2 = ZeroEx.getOrderHashHex(signedOrder2);
+            expirationWatcher.addOrder(orderHash2, signedOrder2.expirationUnixTimestampSec.times(1000));
+            expirationWatcher.addOrder(orderHash1, signedOrder1.expirationUnixTimestampSec.times(1000));
+            const expirationOrder = [orderHash1, orderHash2];
+            const callbackAsync = reportCallbackErrors(done)(async (hash: string) => {
+                const orderHash = expirationOrder.shift();
+                expect(hash).to.be.equal(orderHash);
+                if (_.isEmpty(expirationOrder)) {
+                    done();
+                }
+            });
+            expirationWatcher.subscribe(callbackAsync);
+            timer.tick(order2Lifetime * 1000);
+        })().catch(done);
+    });
+});

packages/0x.js/test/order_state_watcher_test.ts

@@ -0,0 +1,488 @@
+import BigNumber from 'bignumber.js';
+import * as chai from 'chai';
+import * as _ from 'lodash';
+import 'mocha';
+import * as Web3 from 'web3';
+
+import {
+    DecodedLogEvent,
+    ExchangeContractErrs,
+    LogEvent,
+    OrderState,
+    OrderStateInvalid,
+    OrderStateValid,
+    SignedOrder,
+    Token,
+    ZeroEx,
+    ZeroExConfig,
+    ZeroExError,
+} from '../src';
+import {OrderStateWatcher} from '../src/order_watcher/order_state_watcher';
+import {DoneCallback} from '../src/types';
+import {Web3Wrapper} from '../src/web3_wrapper';
+
+import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+import {chaiSetup} from './utils/chai_setup';
+import {constants} from './utils/constants';
+import {FillScenarios} from './utils/fill_scenarios';
+import {reportCallbackErrors} from './utils/report_callback_errors';
+import {TokenUtils} from './utils/token_utils';
+import {web3Factory} from './utils/web3_factory';
+
+const TIMEOUT_MS = 150;
+
+chaiSetup.configure();
+const expect = chai.expect;
+const blockchainLifecycle = new BlockchainLifecycle();
+
+describe('OrderStateWatcher', () => {
+    let web3: Web3;
+    let zeroEx: ZeroEx;
+    let tokens: Token[];
+    let tokenUtils: TokenUtils;
+    let fillScenarios: FillScenarios;
+    let userAddresses: string[];
+    let zrxTokenAddress: string;
+    let exchangeContractAddress: string;
+    let makerToken: Token;
+    let takerToken: Token;
+    let maker: string;
+    let taker: string;
+    let web3Wrapper: Web3Wrapper;
+    let signedOrder: SignedOrder;
+    const config = {
+        networkId: constants.TESTRPC_NETWORK_ID,
+    };
+    const decimals = constants.ZRX_DECIMALS;
+    const fillableAmount = ZeroEx.toBaseUnitAmount(new BigNumber(5), decimals);
+    before(async () => {
+        web3 = web3Factory.create();
+        zeroEx = new ZeroEx(web3.currentProvider, config);
+        exchangeContractAddress = zeroEx.exchange.getContractAddress();
+        userAddresses = await zeroEx.getAvailableAddressesAsync();
+        [, maker, taker] = userAddresses;
+        tokens = await zeroEx.tokenRegistry.getTokensAsync();
+        tokenUtils = new TokenUtils(tokens);
+        zrxTokenAddress = tokenUtils.getProtocolTokenOrThrow().address;
+        fillScenarios = new FillScenarios(zeroEx, userAddresses, tokens, zrxTokenAddress, exchangeContractAddress);
+        [makerToken, takerToken] = tokenUtils.getNonProtocolTokens();
+        web3Wrapper = (zeroEx as any)._web3Wrapper;
+    });
+    beforeEach(async () => {
+        await blockchainLifecycle.startAsync();
+    });
+    afterEach(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    describe('#removeOrder', async () => {
+        it('should successfully remove existing order', async () => {
+            signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerToken.address, takerToken.address, maker, taker, fillableAmount,
+            );
+            const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+            zeroEx.orderStateWatcher.addOrder(signedOrder);
+            expect((zeroEx.orderStateWatcher as any)._orderByOrderHash).to.include({
+                [orderHash]: signedOrder,
+            });
+            let dependentOrderHashes = (zeroEx.orderStateWatcher as any)._dependentOrderHashes;
+            expect(dependentOrderHashes[signedOrder.maker][signedOrder.makerTokenAddress]).to.have.keys(orderHash);
+            zeroEx.orderStateWatcher.removeOrder(orderHash);
+            expect((zeroEx.orderStateWatcher as any)._orderByOrderHash).to.not.include({
+                [orderHash]: signedOrder,
+            });
+            dependentOrderHashes = (zeroEx.orderStateWatcher as any)._dependentOrderHashes;
+            expect(dependentOrderHashes[signedOrder.maker]).to.be.undefined();
+        });
+        it('should no-op when removing a non-existing order', async () => {
+            signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerToken.address, takerToken.address, maker, taker, fillableAmount,
+            );
+            const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+            const nonExistentOrderHash = `0x${orderHash.substr(2).split('').reverse().join('')}`;
+            zeroEx.orderStateWatcher.removeOrder(nonExistentOrderHash);
+        });
+    });
+    describe('#subscribe', async () => {
+        afterEach(async () => {
+            zeroEx.orderStateWatcher.unsubscribe();
+        });
+        it('should fail when trying to subscribe twice', async () => {
+            zeroEx.orderStateWatcher.subscribe(_.noop);
+            expect(() => zeroEx.orderStateWatcher.subscribe(_.noop))
+                .to.throw(ZeroExError.SubscriptionAlreadyPresent);
+        });
+    });
+    describe('tests with cleanup', async () => {
+        afterEach(async () => {
+            zeroEx.orderStateWatcher.unsubscribe();
+            const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+            zeroEx.orderStateWatcher.removeOrder(orderHash);
+        });
+        it('should emit orderStateInvalid when maker allowance set to 0 for watched order', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    expect(orderState.isValid).to.be.false();
+                    const invalidOrderState = orderState as OrderStateInvalid;
+                    expect(invalidOrderState.orderHash).to.be.equal(orderHash);
+                    expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.InsufficientMakerAllowance);
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                await zeroEx.token.setProxyAllowanceAsync(makerToken.address, maker, new BigNumber(0));
+            })().catch(done);
+        });
+        it('should not emit an orderState event when irrelevant Transfer event received', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    throw new Error('OrderState callback fired for irrelevant order');
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                const notTheMaker = userAddresses[0];
+                const anyRecipient = taker;
+                const transferAmount = new BigNumber(2);
+                const notTheMakerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, notTheMaker);
+                await zeroEx.token.transferAsync(makerToken.address, notTheMaker, anyRecipient, transferAmount);
+                setTimeout(() => {
+                    done();
+                }, TIMEOUT_MS);
+            })().catch(done);
+        });
+        it('should emit orderStateInvalid when maker moves balance backing watched order', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    expect(orderState.isValid).to.be.false();
+                    const invalidOrderState = orderState as OrderStateInvalid;
+                    expect(invalidOrderState.orderHash).to.be.equal(orderHash);
+                    expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.InsufficientMakerBalance);
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                const anyRecipient = taker;
+                const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+                await zeroEx.token.transferAsync(makerToken.address, maker, anyRecipient, makerBalance);
+            })().catch(done);
+        });
+        it('should emit orderStateInvalid when watched order fully filled', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    expect(orderState.isValid).to.be.false();
+                    const invalidOrderState = orderState as OrderStateInvalid;
+                    expect(invalidOrderState.orderHash).to.be.equal(orderHash);
+                    expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.OrderRemainingFillAmountZero);
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+
+                const shouldThrowOnInsufficientBalanceOrAllowance = true;
+                await zeroEx.exchange.fillOrderAsync(
+                    signedOrder, fillableAmount, shouldThrowOnInsufficientBalanceOrAllowance, taker,
+                );
+            })().catch(done);
+        });
+        it('should emit orderStateValid when watched order partially filled', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+
+                const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+                const takerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, taker);
+
+                const fillAmountInBaseUnits = new BigNumber(2);
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    expect(orderState.isValid).to.be.true();
+                    const validOrderState = orderState as OrderStateValid;
+                    expect(validOrderState.orderHash).to.be.equal(orderHash);
+                    const orderRelevantState = validOrderState.orderRelevantState;
+                    const remainingMakerBalance = makerBalance.sub(fillAmountInBaseUnits);
+                    const remainingFillable = fillableAmount.minus(fillAmountInBaseUnits);
+                    expect(orderRelevantState.remainingFillableMakerTokenAmount).to.be.bignumber.equal(
+                        remainingFillable);
+                    expect(orderRelevantState.remainingFillableTakerTokenAmount).to.be.bignumber.equal(
+                        remainingFillable);
+                    expect(orderRelevantState.makerBalance).to.be.bignumber.equal(remainingMakerBalance);
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                const shouldThrowOnInsufficientBalanceOrAllowance = true;
+                await zeroEx.exchange.fillOrderAsync(
+                    signedOrder, fillAmountInBaseUnits, shouldThrowOnInsufficientBalanceOrAllowance, taker,
+                );
+            })().catch(done);
+        });
+        it('should trigger the callback when orders backing ZRX allowance changes', (done: DoneCallback) => {
+            (async () => {
+                const makerFee = ZeroEx.toBaseUnitAmount(new BigNumber(2), 18);
+                const takerFee = ZeroEx.toBaseUnitAmount(new BigNumber(0), 18);
+                signedOrder = await fillScenarios.createFillableSignedOrderWithFeesAsync(
+                    makerToken.address, takerToken.address, makerFee, takerFee, maker, taker, fillableAmount,
+                    taker);
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                await zeroEx.token.setProxyAllowanceAsync(zrxTokenAddress, maker, new BigNumber(0));
+            })().catch(done);
+        });
+        describe('remainingFillable(M|T)akerTokenAmount', () => {
+            it('should calculate correct remaining fillable', (done: DoneCallback) => {
+                (async () => {
+                    const takerFillableAmount = ZeroEx.toBaseUnitAmount(new BigNumber(10), decimals);
+                    const makerFillableAmount = ZeroEx.toBaseUnitAmount(new BigNumber(20), decimals);
+                    signedOrder = await fillScenarios.createAsymmetricFillableSignedOrderAsync(
+                        makerToken.address, takerToken.address, maker, taker, makerFillableAmount,
+                        takerFillableAmount,
+                    );
+                    const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+                    const takerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, taker);
+                    const fillAmountInBaseUnits = ZeroEx.toBaseUnitAmount(new BigNumber(2), decimals);
+                    const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+                    const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                        expect(orderState.isValid).to.be.true();
+                        const validOrderState = orderState as OrderStateValid;
+                        expect(validOrderState.orderHash).to.be.equal(orderHash);
+                        const orderRelevantState = validOrderState.orderRelevantState;
+                        expect(orderRelevantState.remainingFillableMakerTokenAmount).to.be.bignumber.equal(
+                            ZeroEx.toBaseUnitAmount(new BigNumber(16), decimals));
+                        expect(orderRelevantState.remainingFillableTakerTokenAmount).to.be.bignumber.equal(
+                            ZeroEx.toBaseUnitAmount(new BigNumber(8), decimals));
+                        done();
+                    });
+                    zeroEx.orderStateWatcher.subscribe(callback);
+                    const shouldThrowOnInsufficientBalanceOrAllowance = true;
+                    await zeroEx.exchange.fillOrderAsync(
+                        signedOrder, fillAmountInBaseUnits, shouldThrowOnInsufficientBalanceOrAllowance, taker,
+                    );
+                })().catch(done);
+            });
+            it('should equal approved amount when approved amount is lowest', (done: DoneCallback) => {
+                (async () => {
+                    signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                        makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                    );
+
+                    const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+
+                    const changedMakerApprovalAmount = ZeroEx.toBaseUnitAmount(new BigNumber(3), decimals);
+                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                    const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                        const validOrderState = orderState as OrderStateValid;
+                        const orderRelevantState = validOrderState.orderRelevantState;
+                        expect(orderRelevantState.remainingFillableMakerTokenAmount).to.be.bignumber.equal(
+                            changedMakerApprovalAmount);
+                        expect(orderRelevantState.remainingFillableTakerTokenAmount).to.be.bignumber.equal(
+                            changedMakerApprovalAmount);
+                        done();
+                    });
+                    zeroEx.orderStateWatcher.subscribe(callback);
+                    await zeroEx.token.setProxyAllowanceAsync(makerToken.address, maker, changedMakerApprovalAmount);
+                })().catch(done);
+            });
+            it('should equal balance amount when balance amount is lowest', (done: DoneCallback) => {
+                (async () => {
+                    signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                        makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                    );
+
+                    const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+
+                    const remainingAmount = ZeroEx.toBaseUnitAmount(new BigNumber(1), decimals);
+                    const transferAmount = makerBalance.sub(remainingAmount);
+                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                    const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                        expect(orderState.isValid).to.be.true();
+                        const validOrderState = orderState as OrderStateValid;
+                        const orderRelevantState = validOrderState.orderRelevantState;
+                        expect(orderRelevantState.remainingFillableMakerTokenAmount).to.be.bignumber.equal(
+                            remainingAmount);
+                        expect(orderRelevantState.remainingFillableTakerTokenAmount).to.be.bignumber.equal(
+                            remainingAmount);
+                        done();
+                    });
+                    zeroEx.orderStateWatcher.subscribe(callback);
+                    await zeroEx.token.transferAsync(
+                        makerToken.address, maker, ZeroEx.NULL_ADDRESS, transferAmount);
+                })().catch(done);
+            });
+            it('should equal remaining amount when partially cancelled and order has fees', (done: DoneCallback) => {
+                (async () => {
+                    const takerFee = ZeroEx.toBaseUnitAmount(new BigNumber(0), decimals);
+                    const makerFee = ZeroEx.toBaseUnitAmount(new BigNumber(5), decimals);
+                    const feeRecipient = taker;
+                    signedOrder = await fillScenarios.createFillableSignedOrderWithFeesAsync(
+                        makerToken.address, takerToken.address, makerFee, takerFee, maker,
+                        taker, fillableAmount, feeRecipient);
+
+                    const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+
+                    const remainingTokenAmount = ZeroEx.toBaseUnitAmount(new BigNumber(4), decimals);
+                    const transferTokenAmount = makerFee.sub(remainingTokenAmount);
+                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                    const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                        expect(orderState.isValid).to.be.true();
+                        const validOrderState = orderState as OrderStateValid;
+                        const orderRelevantState = validOrderState.orderRelevantState;
+                        expect(orderRelevantState.remainingFillableMakerTokenAmount).to.be.bignumber.equal(
+                            remainingTokenAmount);
+                        done();
+                    });
+                    zeroEx.orderStateWatcher.subscribe(callback);
+                    await zeroEx.exchange.cancelOrderAsync(signedOrder, transferTokenAmount);
+                })().catch(done);
+            });
+            it('should equal ratio amount when fee balance is lowered', (done: DoneCallback) => {
+                (async () => {
+                    const takerFee = ZeroEx.toBaseUnitAmount(new BigNumber(0), decimals);
+                    const makerFee = ZeroEx.toBaseUnitAmount(new BigNumber(5), decimals);
+                    const feeRecipient = taker;
+                    signedOrder = await fillScenarios.createFillableSignedOrderWithFeesAsync(
+                        makerToken.address, takerToken.address, makerFee, takerFee, maker,
+                        taker, fillableAmount, feeRecipient);
+
+                    const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+
+                    const remainingFeeAmount = ZeroEx.toBaseUnitAmount(new BigNumber(3), decimals);
+                    const transferFeeAmount = makerFee.sub(remainingFeeAmount);
+
+                    const remainingTokenAmount = ZeroEx.toBaseUnitAmount(new BigNumber(4), decimals);
+                    const transferTokenAmount = makerFee.sub(remainingTokenAmount);
+                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                    const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                        const validOrderState = orderState as OrderStateValid;
+                        const orderRelevantState = validOrderState.orderRelevantState;
+                        expect(orderRelevantState.remainingFillableMakerTokenAmount).to.be.bignumber.equal(
+                            remainingFeeAmount);
+                        done();
+                    });
+                    zeroEx.orderStateWatcher.subscribe(callback);
+                    await zeroEx.token.setProxyAllowanceAsync(zrxTokenAddress, maker, remainingFeeAmount);
+                    await zeroEx.token.transferAsync(
+                        makerToken.address, maker, ZeroEx.NULL_ADDRESS, transferTokenAmount);
+                })().catch(done);
+            });
+            it('should calculate full amount when all available and non-divisible', (done: DoneCallback) => {
+                (async () => {
+                    const takerFee = ZeroEx.toBaseUnitAmount(new BigNumber(0), decimals);
+                    const makerFee = ZeroEx.toBaseUnitAmount(new BigNumber(2), decimals);
+                    const feeRecipient = taker;
+                    signedOrder = await fillScenarios.createFillableSignedOrderWithFeesAsync(
+                        makerToken.address, takerToken.address, makerFee, takerFee, maker,
+                        taker, fillableAmount, feeRecipient);
+
+                    const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+                    zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                    const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                        const validOrderState = orderState as OrderStateValid;
+                        const orderRelevantState = validOrderState.orderRelevantState;
+                        expect(orderRelevantState.remainingFillableMakerTokenAmount).to.be.bignumber.equal(
+                            fillableAmount);
+                        done();
+                    });
+                    zeroEx.orderStateWatcher.subscribe(callback);
+                    await zeroEx.token.setProxyAllowanceAsync(
+                        makerToken.address, maker, ZeroEx.toBaseUnitAmount(new BigNumber(100), decimals));
+                })().catch(done);
+            });
+        });
+        it('should emit orderStateInvalid when watched order cancelled', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    expect(orderState.isValid).to.be.false();
+                    const invalidOrderState = orderState as OrderStateInvalid;
+                    expect(invalidOrderState.orderHash).to.be.equal(orderHash);
+                    expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.OrderRemainingFillAmountZero);
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+
+                const shouldThrowOnInsufficientBalanceOrAllowance = true;
+                await zeroEx.exchange.cancelOrderAsync(signedOrder, fillableAmount);
+            })().catch(done);
+        });
+        it('should emit orderStateInvalid when within rounding error range', (done: DoneCallback) => {
+            (async () => {
+                const remainingFillableAmountInBaseUnits = new BigNumber(100);
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    expect(orderState.isValid).to.be.false();
+                    const invalidOrderState = orderState as OrderStateInvalid;
+                    expect(invalidOrderState.orderHash).to.be.equal(orderHash);
+                    expect(invalidOrderState.error).to.be.equal(ExchangeContractErrs.OrderFillRoundingError);
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                await zeroEx.exchange.cancelOrderAsync(
+                    signedOrder, fillableAmount.minus(remainingFillableAmountInBaseUnits),
+                );
+            })().catch(done);
+        });
+        it('should emit orderStateValid when watched order partially cancelled', (done: DoneCallback) => {
+            (async () => {
+                signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                    makerToken.address, takerToken.address, maker, taker, fillableAmount,
+                );
+
+                const makerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, maker);
+                const takerBalance = await zeroEx.token.getBalanceAsync(makerToken.address, taker);
+
+                const cancelAmountInBaseUnits = new BigNumber(2);
+                const orderHash = ZeroEx.getOrderHashHex(signedOrder);
+                zeroEx.orderStateWatcher.addOrder(signedOrder);
+
+                const callback = reportCallbackErrors(done)((orderState: OrderState) => {
+                    expect(orderState.isValid).to.be.true();
+                    const validOrderState = orderState as OrderStateValid;
+                    expect(validOrderState.orderHash).to.be.equal(orderHash);
+                    const orderRelevantState = validOrderState.orderRelevantState;
+                    expect(orderRelevantState.cancelledTakerTokenAmount).to.be.bignumber.equal(cancelAmountInBaseUnits);
+                    done();
+                });
+                zeroEx.orderStateWatcher.subscribe(callback);
+                await zeroEx.exchange.cancelOrderAsync(signedOrder, cancelAmountInBaseUnits);
+            })().catch(done);
+        });
+    });
+}); // tslint:disable:max-file-line-count

packages/0x.js/test/order_validation_test.ts

@@ -0,0 +1,333 @@
+import BigNumber from 'bignumber.js';
+import * as chai from 'chai';
+import * as Sinon from 'sinon';
+import * as Web3 from 'web3';
+
+import {ExchangeContractErrs, SignedOrder, Token, ZeroEx, ZeroExError} from '../src';
+import {BlockParamLiteral, TradeSide, TransferType} from '../src/types';
+import {ExchangeTransferSimulator} from '../src/utils/exchange_transfer_simulator';
+import {OrderValidationUtils} from '../src/utils/order_validation_utils';
+
+import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+import {chaiSetup} from './utils/chai_setup';
+import {constants} from './utils/constants';
+import {FillScenarios} from './utils/fill_scenarios';
+import {TokenUtils} from './utils/token_utils';
+import {web3Factory} from './utils/web3_factory';
+
+chaiSetup.configure();
+const expect = chai.expect;
+const blockchainLifecycle = new BlockchainLifecycle();
+
+describe('OrderValidation', () => {
+    let web3: Web3;
+    let zeroEx: ZeroEx;
+    let userAddresses: string[];
+    let tokens: Token[];
+    let tokenUtils: TokenUtils;
+    let exchangeContractAddress: string;
+    let zrxTokenAddress: string;
+    let fillScenarios: FillScenarios;
+    let makerTokenAddress: string;
+    let takerTokenAddress: string;
+    let coinbase: string;
+    let makerAddress: string;
+    let takerAddress: string;
+    let feeRecipient: string;
+    let orderValidationUtils: OrderValidationUtils;
+    const fillableAmount = new BigNumber(5);
+    const fillTakerAmount = new BigNumber(5);
+    const config = {
+        networkId: constants.TESTRPC_NETWORK_ID,
+    };
+    before(async () => {
+        web3 = web3Factory.create();
+        zeroEx = new ZeroEx(web3.currentProvider, config);
+        exchangeContractAddress = zeroEx.exchange.getContractAddress();
+        userAddresses = await zeroEx.getAvailableAddressesAsync();
+        [coinbase, makerAddress, takerAddress, feeRecipient] = userAddresses;
+        tokens = await zeroEx.tokenRegistry.getTokensAsync();
+        tokenUtils = new TokenUtils(tokens);
+        zrxTokenAddress = tokenUtils.getProtocolTokenOrThrow().address;
+        fillScenarios = new FillScenarios(zeroEx, userAddresses, tokens, zrxTokenAddress, exchangeContractAddress);
+        const [makerToken, takerToken] = tokenUtils.getNonProtocolTokens();
+        makerTokenAddress = makerToken.address;
+        takerTokenAddress = takerToken.address;
+        orderValidationUtils = new OrderValidationUtils(zeroEx.token, zeroEx.exchange);
+    });
+    beforeEach(async () => {
+        await blockchainLifecycle.startAsync();
+    });
+    afterEach(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    describe('validateOrderFillableOrThrowAsync', () => {
+        it('should succeed if the order is fillable', async () => {
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+            );
+            await zeroEx.exchange.validateOrderFillableOrThrowAsync(
+                signedOrder,
+            );
+        });
+        it('should succeed if the order is asymmetric and fillable', async () => {
+            const makerFillableAmount = fillableAmount;
+            const takerFillableAmount = fillableAmount.minus(4);
+            const signedOrder = await fillScenarios.createAsymmetricFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress,
+                makerFillableAmount, takerFillableAmount,
+            );
+            await zeroEx.exchange.validateOrderFillableOrThrowAsync(
+                signedOrder,
+            );
+        });
+        it('should throw when the order is fully filled or cancelled', async () => {
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+            );
+            await zeroEx.exchange.cancelOrderAsync(signedOrder, fillableAmount);
+            return expect(zeroEx.exchange.validateOrderFillableOrThrowAsync(
+                signedOrder,
+            )).to.be.rejectedWith(ExchangeContractErrs.OrderRemainingFillAmountZero);
+        });
+        it('should throw when order is expired', async () => {
+            const expirationInPast = new BigNumber(1496826058); // 7th Jun 2017
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress,
+                fillableAmount, expirationInPast,
+            );
+            return expect(zeroEx.exchange.validateOrderFillableOrThrowAsync(
+                signedOrder,
+            )).to.be.rejectedWith(ExchangeContractErrs.OrderFillExpired);
+        });
+    });
+    describe('validateFillOrderAndThrowIfInvalidAsync', () => {
+        it('should throw when the fill amount is zero', async () => {
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+            );
+            const zeroFillAmount = new BigNumber(0);
+            return expect(zeroEx.exchange.validateFillOrderThrowIfInvalidAsync(
+                signedOrder, zeroFillAmount, takerAddress,
+            )).to.be.rejectedWith(ExchangeContractErrs.OrderFillAmountZero);
+        });
+        it('should throw when the signature is invalid', async () => {
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+            );
+            // 27 <--> 28
+            signedOrder.ecSignature.v = (28 - signedOrder.ecSignature.v) + 27;
+            return expect(zeroEx.exchange.validateFillOrderThrowIfInvalidAsync(
+                signedOrder, fillableAmount, takerAddress,
+            )).to.be.rejectedWith(ZeroExError.InvalidSignature);
+        });
+        it('should throw when the order is fully filled or cancelled', async () => {
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+            );
+            await zeroEx.exchange.cancelOrderAsync(signedOrder, fillableAmount);
+            return expect(zeroEx.exchange.validateFillOrderThrowIfInvalidAsync(
+                signedOrder, fillableAmount, takerAddress,
+            )).to.be.rejectedWith(ExchangeContractErrs.OrderRemainingFillAmountZero);
+        });
+        it('should throw when sender is not a taker', async () => {
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+            );
+            const nonTakerAddress = userAddresses[6];
+            return expect(zeroEx.exchange.validateFillOrderThrowIfInvalidAsync(
+                signedOrder, fillTakerAmount, nonTakerAddress,
+            )).to.be.rejectedWith(ExchangeContractErrs.TransactionSenderIsNotFillOrderTaker);
+        });
+        it('should throw when order is expired', async () => {
+            const expirationInPast = new BigNumber(1496826058); // 7th Jun 2017
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress,
+                fillableAmount, expirationInPast,
+            );
+            return expect(zeroEx.exchange.validateFillOrderThrowIfInvalidAsync(
+                signedOrder, fillTakerAmount, takerAddress,
+            )).to.be.rejectedWith(ExchangeContractErrs.OrderFillExpired);
+        });
+        it('should throw when there a rounding error would have occurred', async () => {
+            const makerAmount = new BigNumber(3);
+            const takerAmount = new BigNumber(5);
+            const signedOrder = await fillScenarios.createAsymmetricFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress,
+                makerAmount, takerAmount,
+            );
+            const fillTakerAmountThatCausesRoundingError = new BigNumber(3);
+            return expect(zeroEx.exchange.validateFillOrderThrowIfInvalidAsync(
+                signedOrder, fillTakerAmountThatCausesRoundingError, takerAddress,
+            )).to.be.rejectedWith(ExchangeContractErrs.OrderFillRoundingError);
+        });
+    });
+    describe('#validateFillOrKillOrderAndThrowIfInvalidAsync', () => {
+        it('should throw if remaining fillAmount is less then the desired fillAmount', async () => {
+            const signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+            );
+            const tooLargeFillAmount = new BigNumber(7);
+            const fillAmountDifference = tooLargeFillAmount.minus(fillableAmount);
+            await zeroEx.token.transferAsync(takerTokenAddress, coinbase, takerAddress, fillAmountDifference);
+            await zeroEx.token.setProxyAllowanceAsync(takerTokenAddress, takerAddress, tooLargeFillAmount);
+            await zeroEx.token.transferAsync(makerTokenAddress, coinbase, makerAddress, fillAmountDifference);
+            await zeroEx.token.setProxyAllowanceAsync(makerTokenAddress, makerAddress, tooLargeFillAmount);
+
+            return expect(zeroEx.exchange.validateFillOrKillOrderThrowIfInvalidAsync(
+                signedOrder, tooLargeFillAmount, takerAddress,
+            )).to.be.rejectedWith(ExchangeContractErrs.InsufficientRemainingFillAmount);
+        });
+    });
+    describe('validateCancelOrderAndThrowIfInvalidAsync', () => {
+        let signedOrder: SignedOrder;
+        let orderHashHex: string;
+        const cancelAmount = new BigNumber(3);
+        beforeEach(async () => {
+            [coinbase, makerAddress, takerAddress] = userAddresses;
+            const [makerToken, takerToken] = tokenUtils.getNonProtocolTokens();
+            makerTokenAddress = makerToken.address;
+            takerTokenAddress = takerToken.address;
+            signedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, fillableAmount,
+            );
+            orderHashHex = ZeroEx.getOrderHashHex(signedOrder);
+        });
+        it('should throw when cancel amount is zero', async () => {
+            const zeroCancelAmount = new BigNumber(0);
+            return expect(zeroEx.exchange.validateCancelOrderThrowIfInvalidAsync(signedOrder, zeroCancelAmount))
+                .to.be.rejectedWith(ExchangeContractErrs.OrderCancelAmountZero);
+        });
+        it('should throw when order is expired', async () => {
+            const expirationInPast = new BigNumber(1496826058); // 7th Jun 2017
+            const expiredSignedOrder = await fillScenarios.createFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress,
+                fillableAmount, expirationInPast,
+            );
+            orderHashHex = ZeroEx.getOrderHashHex(expiredSignedOrder);
+            return expect(zeroEx.exchange.validateCancelOrderThrowIfInvalidAsync(expiredSignedOrder, cancelAmount))
+                .to.be.rejectedWith(ExchangeContractErrs.OrderCancelExpired);
+        });
+        it('should throw when order is already cancelled or filled', async () => {
+            await zeroEx.exchange.cancelOrderAsync(signedOrder, fillableAmount);
+            return expect(zeroEx.exchange.validateCancelOrderThrowIfInvalidAsync(signedOrder, fillableAmount))
+                .to.be.rejectedWith(ExchangeContractErrs.OrderAlreadyCancelledOrFilled);
+        });
+    });
+    describe('#validateFillOrderBalancesAllowancesThrowIfInvalidAsync', () => {
+        let exchangeTransferSimulator: ExchangeTransferSimulator;
+        let transferFromAsync: Sinon.SinonSpy;
+        const bigNumberMatch = (expected: BigNumber) => {
+            return Sinon.match((value: BigNumber) => value.eq(expected));
+        };
+        beforeEach('create exchangeTransferSimulator', async () => {
+            exchangeTransferSimulator = new ExchangeTransferSimulator(zeroEx.token, BlockParamLiteral.Latest);
+            transferFromAsync = Sinon.spy();
+            exchangeTransferSimulator.transferFromAsync = transferFromAsync as any;
+        });
+        it('should call exchangeTransferSimulator.transferFrom in a correct order', async () => {
+            const makerFee = new BigNumber(2);
+            const takerFee = new BigNumber(2);
+            const signedOrder = await fillScenarios.createFillableSignedOrderWithFeesAsync(
+                makerTokenAddress, takerTokenAddress, makerFee, takerFee,
+                makerAddress, takerAddress, fillableAmount, feeRecipient,
+            );
+            await OrderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+                exchangeTransferSimulator, signedOrder, fillableAmount, takerAddress, zrxTokenAddress,
+            );
+            expect(transferFromAsync.callCount).to.be.equal(4);
+            expect(
+                transferFromAsync.getCall(0).calledWith(
+                    makerTokenAddress, makerAddress, takerAddress, bigNumberMatch(fillableAmount),
+                    TradeSide.Maker, TransferType.Trade,
+                ),
+            ).to.be.true();
+            expect(
+                transferFromAsync.getCall(1).calledWith(
+                    takerTokenAddress, takerAddress, makerAddress, bigNumberMatch(fillableAmount),
+                    TradeSide.Taker, TransferType.Trade,
+                ),
+            ).to.be.true();
+            expect(
+                transferFromAsync.getCall(2).calledWith(
+                    zrxTokenAddress, makerAddress, feeRecipient, bigNumberMatch(makerFee),
+                    TradeSide.Maker, TransferType.Fee,
+                ),
+            ).to.be.true();
+            expect(
+                transferFromAsync.getCall(3).calledWith(
+                    zrxTokenAddress, takerAddress, feeRecipient, bigNumberMatch(takerFee),
+                    TradeSide.Taker, TransferType.Fee,
+                ),
+            ).to.be.true();
+        });
+        it('should call exchangeTransferSimulator.transferFrom with correct values for an open order', async () => {
+            const makerFee = new BigNumber(2);
+            const takerFee = new BigNumber(2);
+            const signedOrder = await fillScenarios.createFillableSignedOrderWithFeesAsync(
+                makerTokenAddress, takerTokenAddress, makerFee, takerFee,
+                makerAddress, ZeroEx.NULL_ADDRESS, fillableAmount, feeRecipient,
+            );
+            await OrderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+                exchangeTransferSimulator, signedOrder, fillableAmount, takerAddress, zrxTokenAddress,
+            );
+            expect(transferFromAsync.callCount).to.be.equal(4);
+            expect(
+                transferFromAsync.getCall(0).calledWith(
+                    makerTokenAddress, makerAddress, takerAddress, bigNumberMatch(fillableAmount),
+                    TradeSide.Maker, TransferType.Trade,
+                ),
+            ).to.be.true();
+            expect(
+                transferFromAsync.getCall(1).calledWith(
+                    takerTokenAddress, takerAddress, makerAddress, bigNumberMatch(fillableAmount),
+                    TradeSide.Taker, TransferType.Trade,
+                ),
+            ).to.be.true();
+            expect(
+                transferFromAsync.getCall(2).calledWith(
+                    zrxTokenAddress, makerAddress, feeRecipient, bigNumberMatch(makerFee),
+                    TradeSide.Maker, TransferType.Fee,
+                ),
+            ).to.be.true();
+            expect(
+                transferFromAsync.getCall(3).calledWith(
+                    zrxTokenAddress, takerAddress, feeRecipient, bigNumberMatch(takerFee),
+                    TradeSide.Taker, TransferType.Fee,
+                ),
+            ).to.be.true();
+        });
+        it('should correctly round the fillMakerTokenAmount', async () => {
+            const makerTokenAmount = new BigNumber(3);
+            const takerTokenAmount = new BigNumber(1);
+            const signedOrder = await fillScenarios.createAsymmetricFillableSignedOrderAsync(
+                makerTokenAddress, takerTokenAddress, makerAddress, takerAddress, makerTokenAmount, takerTokenAmount,
+            );
+            await OrderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+                exchangeTransferSimulator, signedOrder, takerTokenAmount, takerAddress, zrxTokenAddress,
+            );
+            expect(transferFromAsync.callCount).to.be.equal(4);
+            const makerFillAmount = transferFromAsync.getCall(0).args[3];
+            expect(makerFillAmount).to.be.bignumber.equal(makerTokenAmount);
+        });
+        it('should correctly round the makerFeeAmount', async () => {
+            const makerFee = new BigNumber(2);
+            const takerFee = new BigNumber(4);
+            const signedOrder = await fillScenarios.createFillableSignedOrderWithFeesAsync(
+                makerTokenAddress, takerTokenAddress, makerFee, takerFee, makerAddress, takerAddress,
+                fillableAmount, ZeroEx.NULL_ADDRESS,
+            );
+            const fillTakerTokenAmount = fillableAmount.div(2).round(0);
+            await OrderValidationUtils.validateFillOrderBalancesAllowancesThrowIfInvalidAsync(
+                exchangeTransferSimulator, signedOrder, fillTakerTokenAmount, takerAddress, zrxTokenAddress,
+            );
+            const makerPartialFee = makerFee.div(2);
+            const takerPartialFee = takerFee.div(2);
+            expect(transferFromAsync.callCount).to.be.equal(4);
+            const partialMakerFee = transferFromAsync.getCall(2).args[3];
+            expect(partialMakerFee).to.be.bignumber.equal(makerPartialFee);
+            const partialTakerFee = transferFromAsync.getCall(3).args[3];
+            expect(partialTakerFee).to.be.bignumber.equal(takerPartialFee);
+        });
+    });
+});

packages/0x.js/test/remaining_fillable_calculator_test.ts

@@ -0,0 +1,178 @@
+import BigNumber from 'bignumber.js';
+import * as chai from 'chai';
+import 'mocha';
+
+import { ZeroEx } from '../src/0x';
+import { RemainingFillableCalculator } from '../src/order_watcher/remaining_fillable_calculator';
+import { ECSignature, SignedOrder } from '../src/types';
+
+import { chaiSetup } from './utils/chai_setup';
+import { TokenUtils } from './utils/token_utils';
+
+chaiSetup.configure();
+const expect = chai.expect;
+
+describe('RemainingFillableCalculator', () => {
+    let calculator: RemainingFillableCalculator;
+    let signedOrder: SignedOrder;
+    let transferrableMakerTokenAmount: BigNumber;
+    let transferrableMakerFeeTokenAmount: BigNumber;
+    let remainingMakerTokenAmount: BigNumber;
+    let makerAmount: BigNumber;
+    let takerAmount: BigNumber;
+    let makerFeeAmount: BigNumber;
+    let isMakerTokenZRX: boolean;
+    const makerToken: string = '0x1';
+    const takerToken: string = '0x2';
+    const decimals: number = 4;
+    const zero: BigNumber = new BigNumber(0);
+    const zeroAddress = '0x0';
+    const signature: ECSignature = { v: 27, r: '', s: ''};
+    beforeEach(async () => {
+        [makerAmount, takerAmount, makerFeeAmount] = [ZeroEx.toBaseUnitAmount(new BigNumber(50), decimals),
+                                                      ZeroEx.toBaseUnitAmount(new BigNumber(5), decimals),
+                                                      ZeroEx.toBaseUnitAmount(new BigNumber(1), decimals)];
+        [transferrableMakerTokenAmount, transferrableMakerFeeTokenAmount] = [
+                                                ZeroEx.toBaseUnitAmount(new BigNumber(50), decimals),
+                                                ZeroEx.toBaseUnitAmount(new BigNumber(5), decimals)];
+    });
+    function buildSignedOrder(): SignedOrder {
+        return { ecSignature: signature,
+                 exchangeContractAddress: zeroAddress,
+                 feeRecipient: zeroAddress,
+                 maker: zeroAddress,
+                 taker: zeroAddress,
+                 makerFee: makerFeeAmount,
+                 takerFee: zero,
+                 makerTokenAmount: makerAmount,
+                 takerTokenAmount: takerAmount,
+                 makerTokenAddress: makerToken,
+                 takerTokenAddress: takerToken,
+                 salt: zero,
+                 expirationUnixTimestampSec: zero };
+    }
+    describe('Maker token is NOT ZRX', () => {
+        before(async () => {
+            isMakerTokenZRX = false;
+        });
+        it('calculates the correct amount when unfilled and funds available', () => {
+            signedOrder = buildSignedOrder();
+            remainingMakerTokenAmount = signedOrder.makerTokenAmount;
+            calculator = new RemainingFillableCalculator(signedOrder, isMakerTokenZRX,
+                           transferrableMakerTokenAmount, transferrableMakerFeeTokenAmount, remainingMakerTokenAmount);
+            expect(calculator.computeRemainingMakerFillable()).to.be.bignumber.equal(remainingMakerTokenAmount);
+        });
+        it('calculates the correct amount when partially filled and funds available', () => {
+            signedOrder = buildSignedOrder();
+            remainingMakerTokenAmount = ZeroEx.toBaseUnitAmount(new BigNumber(1), decimals);
+            calculator = new RemainingFillableCalculator(signedOrder, isMakerTokenZRX,
+                           transferrableMakerTokenAmount, transferrableMakerFeeTokenAmount, remainingMakerTokenAmount);
+            expect(calculator.computeRemainingMakerFillable()).to.be.bignumber.equal(remainingMakerTokenAmount);
+        });
+        it('calculates the amount to be 0 when all fee funds are transferred', () => {
+            signedOrder = buildSignedOrder();
+            transferrableMakerFeeTokenAmount = zero;
+            remainingMakerTokenAmount = signedOrder.makerTokenAmount;
+            calculator = new RemainingFillableCalculator(signedOrder, isMakerTokenZRX,
+                           transferrableMakerTokenAmount, transferrableMakerFeeTokenAmount, remainingMakerTokenAmount);
+            expect(calculator.computeRemainingMakerFillable()).to.be.bignumber.equal(zero);
+        });
+        it('calculates the correct amount when balance is less than remaining fillable', () => {
+            signedOrder = buildSignedOrder();
+            const partiallyFilledAmount = ZeroEx.toBaseUnitAmount(new BigNumber(2), decimals);
+            remainingMakerTokenAmount = signedOrder.makerTokenAmount.minus(partiallyFilledAmount);
+            transferrableMakerTokenAmount = remainingMakerTokenAmount.minus(partiallyFilledAmount);
+            calculator = new RemainingFillableCalculator(signedOrder, isMakerTokenZRX,
+                           transferrableMakerTokenAmount, transferrableMakerFeeTokenAmount, remainingMakerTokenAmount);
+            expect(calculator.computeRemainingMakerFillable()).to.be.bignumber.equal(transferrableMakerTokenAmount);
+        });
+        describe('Order to Fee Ratio is < 1', () => {
+            beforeEach(async () => {
+                [makerAmount, takerAmount, makerFeeAmount] = [ZeroEx.toBaseUnitAmount(new BigNumber(3), decimals),
+                                                              ZeroEx.toBaseUnitAmount(new BigNumber(6), decimals),
+                                                              ZeroEx.toBaseUnitAmount(new BigNumber(6), decimals)];
+            });
+            it('calculates the correct amount when funds unavailable', () => {
+                signedOrder = buildSignedOrder();
+                remainingMakerTokenAmount = signedOrder.makerTokenAmount;
+                const transferredAmount = ZeroEx.toBaseUnitAmount(new BigNumber(2), decimals);
+                transferrableMakerTokenAmount = remainingMakerTokenAmount.minus(transferredAmount);
+                calculator = new RemainingFillableCalculator(signedOrder, isMakerTokenZRX,
+                                 transferrableMakerTokenAmount, transferrableMakerFeeTokenAmount,
+                                 remainingMakerTokenAmount);
+                expect(calculator.computeRemainingMakerFillable()).to.be.bignumber.equal(transferrableMakerTokenAmount);
+            });
+        });
+        describe('Ratio is not evenly divisble', () => {
+            beforeEach(async () => {
+                [makerAmount, takerAmount, makerFeeAmount] = [ZeroEx.toBaseUnitAmount(new BigNumber(3), decimals),
+                                                              ZeroEx.toBaseUnitAmount(new BigNumber(7), decimals),
+                                                              ZeroEx.toBaseUnitAmount(new BigNumber(7), decimals)];
+            });
+            it('calculates the correct amount when funds unavailable', () => {
+                signedOrder = buildSignedOrder();
+                remainingMakerTokenAmount = signedOrder.makerTokenAmount;
+                const transferredAmount = ZeroEx.toBaseUnitAmount(new BigNumber(2), decimals);
+                transferrableMakerTokenAmount = remainingMakerTokenAmount.minus(transferredAmount);
+                calculator = new RemainingFillableCalculator(signedOrder, isMakerTokenZRX,
+                                 transferrableMakerTokenAmount, transferrableMakerFeeTokenAmount,
+                                 remainingMakerTokenAmount);
+                const calculatedFillableAmount = calculator.computeRemainingMakerFillable();
+                expect(calculatedFillableAmount.lessThanOrEqualTo(transferrableMakerTokenAmount)).to.be.true();
+                expect(calculatedFillableAmount).to.be.bignumber.greaterThan(new BigNumber(0));
+                const orderToFeeRatio = signedOrder.makerTokenAmount.dividedBy(signedOrder.makerFee);
+                const calculatedFeeAmount = calculatedFillableAmount.dividedBy(orderToFeeRatio);
+                expect(calculatedFeeAmount).to.be.bignumber.lessThan(transferrableMakerFeeTokenAmount);
+            });
+        });
+    });
+    describe('Maker Token is ZRX', () => {
+        before(async () => {
+            isMakerTokenZRX = true;
+        });
+        it('calculates the correct amount when unfilled and funds available', () => {
+            signedOrder = buildSignedOrder();
+            transferrableMakerTokenAmount = makerAmount.plus(makerFeeAmount);
+            transferrableMakerFeeTokenAmount = transferrableMakerTokenAmount;
+            remainingMakerTokenAmount = signedOrder.makerTokenAmount;
+            calculator = new RemainingFillableCalculator(signedOrder, isMakerTokenZRX,
+                           transferrableMakerTokenAmount, transferrableMakerFeeTokenAmount, remainingMakerTokenAmount);
+            expect(calculator.computeRemainingMakerFillable()).to.be.bignumber.equal(remainingMakerTokenAmount);
+        });
+        it('calculates the correct amount when partially filled and funds available', () => {
+            signedOrder = buildSignedOrder();
+            remainingMakerTokenAmount = ZeroEx.toBaseUnitAmount(new BigNumber(1), decimals);
+            calculator = new RemainingFillableCalculator(signedOrder, isMakerTokenZRX,
+                           transferrableMakerTokenAmount, transferrableMakerFeeTokenAmount, remainingMakerTokenAmount);
+            expect(calculator.computeRemainingMakerFillable()).to.be.bignumber.equal(remainingMakerTokenAmount);
+        });
+        it('calculates the amount to be 0 when all fee funds are transferred', () => {
+            signedOrder = buildSignedOrder();
+            transferrableMakerTokenAmount = zero;
+            transferrableMakerFeeTokenAmount = zero;
+            remainingMakerTokenAmount = signedOrder.makerTokenAmount;
+            calculator = new RemainingFillableCalculator(signedOrder, isMakerTokenZRX,
+                           transferrableMakerTokenAmount, transferrableMakerFeeTokenAmount, remainingMakerTokenAmount);
+            expect(calculator.computeRemainingMakerFillable()).to.be.bignumber.equal(zero);
+        });
+        it('calculates the correct amount when balance is less than remaining fillable', () => {
+            signedOrder = buildSignedOrder();
+            const partiallyFilledAmount = ZeroEx.toBaseUnitAmount(new BigNumber(2), decimals);
+            remainingMakerTokenAmount = signedOrder.makerTokenAmount.minus(partiallyFilledAmount);
+            transferrableMakerTokenAmount = remainingMakerTokenAmount.minus(partiallyFilledAmount);
+            transferrableMakerFeeTokenAmount = transferrableMakerTokenAmount;
+
+            const orderToFeeRatio = signedOrder.makerTokenAmount.dividedToIntegerBy(signedOrder.makerFee);
+            const expectedFillableAmount = new BigNumber(450980);
+            calculator = new RemainingFillableCalculator(signedOrder, isMakerTokenZRX,
+                           transferrableMakerTokenAmount, transferrableMakerFeeTokenAmount, remainingMakerTokenAmount);
+            const calculatedFillableAmount = calculator.computeRemainingMakerFillable();
+            const numberOfFillsInRatio = calculatedFillableAmount.dividedToIntegerBy(orderToFeeRatio);
+            const calculatedFillableAmountPlusFees = calculatedFillableAmount.plus(numberOfFillsInRatio);
+            expect(calculatedFillableAmountPlusFees).to.be.bignumber.lessThan(transferrableMakerTokenAmount);
+            expect(calculatedFillableAmountPlusFees).to.be.bignumber.lessThan(remainingMakerTokenAmount);
+            expect(calculatedFillableAmount).to.be.bignumber.equal(expectedFillableAmount);
+            expect(numberOfFillsInRatio.decimalPlaces()).to.be.equal(0);
+        });
+    });
+});

packages/0x.js/test/subscription_test.ts

@@ -0,0 +1,124 @@
+import BigNumber from 'bignumber.js';
+import * as chai from 'chai';
+import promisify = require('es6-promisify');
+import * as _ from 'lodash';
+import 'mocha';
+import * as Sinon from 'sinon';
+import * as Web3 from 'web3';
+
+import {
+    ApprovalContractEventArgs,
+    DecodedLogEvent,
+    Token,
+    TokenEvents,
+    ZeroEx,
+    ZeroExError,
+} from '../src';
+import {BlockParamLiteral, DoneCallback} from '../src/types';
+
+import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+import {chaiSetup} from './utils/chai_setup';
+import {constants} from './utils/constants';
+import {reportCallbackErrors} from './utils/report_callback_errors';
+import {TokenUtils} from './utils/token_utils';
+import {web3Factory} from './utils/web3_factory';
+
+chaiSetup.configure();
+const expect = chai.expect;
+const blockchainLifecycle = new BlockchainLifecycle();
+
+describe('SubscriptionTest', () => {
+    let web3: Web3;
+    let zeroEx: ZeroEx;
+    let userAddresses: string[];
+    let tokens: Token[];
+    let tokenUtils: TokenUtils;
+    let coinbase: string;
+    let addressWithoutFunds: string;
+    const config = {
+        networkId: constants.TESTRPC_NETWORK_ID,
+    };
+    before(async () => {
+        web3 = web3Factory.create();
+        zeroEx = new ZeroEx(web3.currentProvider, config);
+        userAddresses = await zeroEx.getAvailableAddressesAsync();
+        tokens = await zeroEx.tokenRegistry.getTokensAsync();
+        tokenUtils = new TokenUtils(tokens);
+        coinbase = userAddresses[0];
+        addressWithoutFunds = userAddresses[1];
+    });
+    beforeEach(async () => {
+        await blockchainLifecycle.startAsync();
+    });
+    afterEach(async () => {
+        await blockchainLifecycle.revertAsync();
+    });
+    describe('#subscribe', () => {
+        const indexFilterValues = {};
+        const shouldThrowOnInsufficientBalanceOrAllowance = true;
+        let tokenAddress: string;
+        const transferAmount = new BigNumber(42);
+        const allowanceAmount = new BigNumber(42);
+        let stubs: Sinon.SinonStub[] = [];
+        before(() => {
+            const token = tokens[0];
+            tokenAddress = token.address;
+        });
+        afterEach(() => {
+            zeroEx.token.unsubscribeAll();
+            _.each(stubs, s => s.restore());
+            stubs = [];
+        });
+        it('Should receive the Error when an error occurs while fetching the block', (done: DoneCallback) => {
+            (async () => {
+                const errMsg = 'Error fetching block';
+                const callback = reportCallbackErrors(done)(
+                    (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
+                        expect(err.message).to.be.equal(errMsg);
+                        expect(logEvent).to.be.undefined();
+                        done();
+                    },
+                );
+                stubs = [
+                  Sinon.stub((zeroEx as any)._web3Wrapper, 'getBlockAsync')
+                   .throws(new Error(errMsg)),
+                ];
+                zeroEx.token.subscribe(
+                    tokenAddress, TokenEvents.Approval, indexFilterValues, callback);
+                await zeroEx.token.setAllowanceAsync(tokenAddress, coinbase, addressWithoutFunds, allowanceAmount);
+            })().catch(done);
+        });
+        it('Should receive the Error when an error occurs while reconciling the new block', (done: DoneCallback) => {
+            (async () => {
+                const errMsg = 'Error fetching logs';
+                const callback = reportCallbackErrors(done)(
+                    (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
+                        expect(err.message).to.be.equal(errMsg);
+                        expect(logEvent).to.be.undefined();
+                        done();
+                    },
+                );
+                stubs = [
+                  Sinon.stub((zeroEx as any)._web3Wrapper, 'getLogsAsync')
+                   .throws(new Error(errMsg)),
+                ];
+                zeroEx.token.subscribe(
+                    tokenAddress, TokenEvents.Approval, indexFilterValues, callback);
+                await zeroEx.token.setAllowanceAsync(tokenAddress, coinbase, addressWithoutFunds, allowanceAmount);
+            })().catch(done);
+        });
+        it('Should allow unsubscribeAll to be called successfully after an error', (done: DoneCallback) => {
+            (async () => {
+                const callback = (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => _.noop;
+                zeroEx.token.subscribe(
+                    tokenAddress, TokenEvents.Approval, indexFilterValues, callback);
+                stubs = [
+                  Sinon.stub((zeroEx as any)._web3Wrapper, 'getBlockAsync')
+                   .throws(new Error('JSON RPC error')),
+                ];
+                zeroEx.token.unsubscribeAll();
+                done();
+            })().catch(done);
+        });
+    });
+});

packages/0x.js/test/token_registry_wrapper_test.ts

@@ -1,11 +1,14 @@
+import {schemas, SchemaValidator} from '@0xproject/json-schemas';
+import * as chai from 'chai';
 import * as _ from 'lodash';
 import 'mocha';
-import * as chai from 'chai';
-import {SchemaValidator, schemas} from '0x-json-schemas';
-import {chaiSetup} from './utils/chai_setup';
-import {web3Factory} from './utils/web3_factory';
-import {ZeroEx, Token} from '../src';
+
+import {Token, ZeroEx} from '../src';
+
 import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+import {chaiSetup} from './utils/chai_setup';
+import {constants} from './utils/constants';
+import {web3Factory} from './utils/web3_factory';
 
 chaiSetup.configure();
 const expect = chai.expect;
@@ -24,9 +27,12 @@ describe('TokenRegistryWrapper', () => {
     const registeredName = '0x Protocol Token';
     const unregisteredSymbol = 'MAL';
     const unregisteredName = 'Malicious Token';
+    const config = {
+        networkId: constants.TESTRPC_NETWORK_ID,
+    };
     before(async () => {
         const web3 = web3Factory.create();
-        zeroEx = new ZeroEx(web3.currentProvider);
+        zeroEx = new ZeroEx(web3.currentProvider, config);
         tokens = await zeroEx.tokenRegistry.getTokensAsync();
         _.map(tokens, token => {
             tokenAddressBySymbol[token.symbol] = token.address;

packages/0x.js/test/token_transfer_proxy_wrapper_test.ts

@@ -1,17 +1,23 @@
 import * as chai from 'chai';
-import {chaiSetup} from './utils/chai_setup';
-import {web3Factory} from './utils/web3_factory';
+
 import {ZeroEx} from '../src';
 import {TokenTransferProxyWrapper} from '../src/contract_wrappers/token_transfer_proxy_wrapper';
 
+import {chaiSetup} from './utils/chai_setup';
+import {constants} from './utils/constants';
+import {web3Factory} from './utils/web3_factory';
+
 chaiSetup.configure();
 const expect = chai.expect;
 
 describe('TokenTransferProxyWrapper', () => {
     let zeroEx: ZeroEx;
+    const config = {
+        networkId: constants.TESTRPC_NETWORK_ID,
+    };
     before(async () => {
         const web3 = web3Factory.create();
-        zeroEx = new ZeroEx(web3.currentProvider);
+        zeroEx = new ZeroEx(web3.currentProvider, config);
     });
     describe('#isAuthorizedAsync', () => {
         it('should return false if the address is not authorized', async () => {

packages/0x.js/test/token_wrapper_test.ts

@@ -1,24 +1,30 @@
-import 'mocha';
+import BigNumber from 'bignumber.js';
 import * as chai from 'chai';
-import {chaiSetup} from './utils/chai_setup';
-import * as Web3 from 'web3';
-import * as BigNumber from 'bignumber.js';
 import promisify = require('es6-promisify');
-import {web3Factory} from './utils/web3_factory';
+import 'mocha';
+import * as Web3 from 'web3';
+
 import {
+    ApprovalContractEventArgs,
+    ContractEvent,
+    DecodedLogEvent,
+    LogEvent,
+    LogWithDecodedArgs,
+    SubscriptionOpts,
+    Token,
+    TokenContractEventArgs,
+    TokenEvents,
+    TransferContractEventArgs,
     ZeroEx,
     ZeroExError,
-    Token,
-    SubscriptionOpts,
-    TokenEvents,
-    ContractEvent,
-    TransferContractEventArgs,
-    ApprovalContractEventArgs,
-    LogWithDecodedArgs,
 } from '../src';
+import {BlockParamLiteral, DoneCallback} from '../src/types';
+
 import {BlockchainLifecycle} from './utils/blockchain_lifecycle';
+import {chaiSetup} from './utils/chai_setup';
+import {constants} from './utils/constants';
 import {TokenUtils} from './utils/token_utils';
-import {DoneCallback} from '../src/types';
+import {web3Factory} from './utils/web3_factory';
 
 chaiSetup.configure();
 const expect = chai.expect;
@@ -32,9 +38,12 @@ describe('TokenWrapper', () => {
     let tokenUtils: TokenUtils;
     let coinbase: string;
     let addressWithoutFunds: string;
+    const config = {
+        networkId: constants.TESTRPC_NETWORK_ID,
+    };
     before(async () => {
         web3 = web3Factory.create();
-        zeroEx = new ZeroEx(web3.currentProvider);
+        zeroEx = new ZeroEx(web3.currentProvider, config);
         userAddresses = await zeroEx.getAvailableAddressesAsync();
         tokens = await zeroEx.tokenRegistry.getTokensAsync();
         tokenUtils = new TokenUtils(tokens);
@@ -49,7 +58,7 @@ describe('TokenWrapper', () => {
     });
     describe('#transferAsync', () => {
         let token: Token;
-        let transferAmount: BigNumber.BigNumber;
+        let transferAmount: BigNumber;
         before(() => {
             token = tokens[0];
             transferAmount = new BigNumber(42);
@@ -60,7 +69,7 @@ describe('TokenWrapper', () => {
             const preBalance = await zeroEx.token.getBalanceAsync(token.address, toAddress);
             expect(preBalance).to.be.bignumber.equal(0);
             const txHash = await zeroEx.token.transferAsync(token.address, fromAddress, toAddress, transferAmount);
-            await zeroEx.awaitTransactionMinedAsync(txHash);
+            const receipt = await zeroEx.awaitTransactionMinedAsync(txHash);
             const postBalance = await zeroEx.token.getBalanceAsync(token.address, toAddress);
             return expect(postBalance).to.be.bignumber.equal(transferAmount);
         });
@@ -77,7 +86,7 @@ describe('TokenWrapper', () => {
             const toAddress = coinbase;
             return expect(zeroEx.token.transferAsync(
                 nonExistentTokenAddress, fromAddress, toAddress, transferAmount,
-            )).to.be.rejectedWith(ZeroExError.ContractDoesNotExist);
+            )).to.be.rejectedWith(ZeroExError.TokenContractDoesNotExist);
         });
     });
     describe('#transferFromAsync', () => {
@@ -150,7 +159,7 @@ describe('TokenWrapper', () => {
             const nonExistentTokenAddress = '0x9dd402f14d67e001d8efbe6583e51bf9706aa065';
             return expect(zeroEx.token.transferFromAsync(
                 nonExistentTokenAddress, fromAddress, toAddress, senderAddress, new BigNumber(42),
-            )).to.be.rejectedWith(ZeroExError.ContractDoesNotExist);
+            )).to.be.rejectedWith(ZeroExError.TokenContractDoesNotExist);
         });
     });
     describe('#getBalanceAsync', () => {
@@ -159,14 +168,14 @@ describe('TokenWrapper', () => {
                 const token = tokens[0];
                 const ownerAddress = coinbase;
                 const balance = await zeroEx.token.getBalanceAsync(token.address, ownerAddress);
-                const expectedBalance = new BigNumber('100000000000000000000000000');
+                const expectedBalance = new BigNumber('1000000000000000000000000000');
                 return expect(balance).to.be.bignumber.equal(expectedBalance);
             });
             it('should throw a CONTRACT_DOES_NOT_EXIST error for a non-existent token contract', async () => {
                 const nonExistentTokenAddress = '0x9dd402f14d67e001d8efbe6583e51bf9706aa065';
                 const ownerAddress = coinbase;
                 return expect(zeroEx.token.getBalanceAsync(nonExistentTokenAddress, ownerAddress))
-                    .to.be.rejectedWith(ZeroExError.ContractDoesNotExist);
+                    .to.be.rejectedWith(ZeroExError.TokenContractDoesNotExist);
             });
             it('should return a balance of 0 for a non-existent owner address', async () => {
                 const token = tokens[0];
@@ -181,13 +190,13 @@ describe('TokenWrapper', () => {
             before(async () => {
                 const hasAddresses = false;
                 const web3WithoutAccounts = web3Factory.create(hasAddresses);
-                zeroExWithoutAccounts = new ZeroEx(web3WithoutAccounts.currentProvider);
+                zeroExWithoutAccounts = new ZeroEx(web3WithoutAccounts.currentProvider, config);
             });
             it('should return balance even when called with Web3 provider instance without addresses', async () => {
                     const token = tokens[0];
                     const ownerAddress = coinbase;
                     const balance = await zeroExWithoutAccounts.token.getBalanceAsync(token.address, ownerAddress);
-                    const expectedBalance = new BigNumber('100000000000000000000000000');
+                    const expectedBalance = new BigNumber('1000000000000000000000000000');
                     return expect(balance).to.be.bignumber.equal(expectedBalance);
             });
         });
@@ -278,7 +287,7 @@ describe('TokenWrapper', () => {
             before(async () => {
                 const hasAddresses = false;
                 const web3WithoutAccounts = web3Factory.create(hasAddresses);
-                zeroExWithoutAccounts = new ZeroEx(web3WithoutAccounts.currentProvider);
+                zeroExWithoutAccounts = new ZeroEx(web3WithoutAccounts.currentProvider, config);
             });
             it('should get the proxy allowance', async () => {
                 const token = tokens[0];
@@ -336,132 +345,118 @@ describe('TokenWrapper', () => {
             return expect(allowance).to.be.bignumber.equal(zeroEx.token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS);
         });
     });
-    describe('#subscribeAsync', () => {
+    describe('#subscribe', () => {
         const indexFilterValues = {};
         const shouldThrowOnInsufficientBalanceOrAllowance = true;
         let tokenAddress: string;
-        const subscriptionOpts: SubscriptionOpts = {
-            fromBlock: 0,
-            toBlock: 'latest',
-        };
         const transferAmount = new BigNumber(42);
         const allowanceAmount = new BigNumber(42);
         before(() => {
             const token = tokens[0];
             tokenAddress = token.address;
         });
-        afterEach(async () => {
-            await zeroEx.token.stopWatchingAllEventsAsync();
+        afterEach(() => {
+            zeroEx.token.unsubscribeAll();
         });
         // Hack: Mocha does not allow a test to be both async and have a `done` callback
-        // Since we need to await the receipt of the event in the `subscribeAsync` callback,
+        // Since we need to await the receipt of the event in the `subscribe` callback,
         // we do need both. A hack is to make the top-level a sync fn w/ a done callback and then
         // wrap the rest of the test in an async block
         // Source: https://github.com/mochajs/mocha/issues/2407
         it('Should receive the Transfer event when tokens are transfered', (done: DoneCallback) => {
             (async () => {
-                const zeroExEvent = await zeroEx.token.subscribeAsync(
-                    tokenAddress, TokenEvents.Transfer, subscriptionOpts, indexFilterValues);
-                zeroExEvent.watch((err: Error, event: ContractEvent) => {
-                    expect(err).to.be.null();
-                    expect(event).to.not.be.undefined();
-                    const args = event.args as TransferContractEventArgs;
+                const callback = (err: Error, logEvent: DecodedLogEvent<TransferContractEventArgs>) => {
+                    expect(logEvent).to.not.be.undefined();
+                    expect(logEvent.isRemoved).to.be.false();
+                    expect(logEvent.log.logIndex).to.be.equal(0);
+                    expect(logEvent.log.transactionIndex).to.be.equal(0);
+                    expect(logEvent.log.blockNumber).to.be.a('number');
+                    const args = logEvent.log.args;
                     expect(args._from).to.be.equal(coinbase);
                     expect(args._to).to.be.equal(addressWithoutFunds);
                     expect(args._value).to.be.bignumber.equal(transferAmount);
                     done();
-                });
+                };
+                zeroEx.token.subscribe(
+                    tokenAddress, TokenEvents.Transfer, indexFilterValues, callback);
                 await zeroEx.token.transferAsync(tokenAddress, coinbase, addressWithoutFunds, transferAmount);
             })().catch(done);
         });
         it('Should receive the Approval event when allowance is being set', (done: DoneCallback) => {
             (async () => {
-                const zeroExEvent = await zeroEx.token.subscribeAsync(
-                    tokenAddress, TokenEvents.Approval, subscriptionOpts, indexFilterValues);
-                zeroExEvent.watch((err: Error, event: ContractEvent) => {
-                    expect(err).to.be.null();
-                    expect(event).to.not.be.undefined();
-                    const args = event.args as ApprovalContractEventArgs;
+                const callback = (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
+                    expect(logEvent).to.not.be.undefined();
+                    expect(logEvent.isRemoved).to.be.false();
+                    const args = logEvent.log.args;
                     expect(args._owner).to.be.equal(coinbase);
                     expect(args._spender).to.be.equal(addressWithoutFunds);
                     expect(args._value).to.be.bignumber.equal(allowanceAmount);
                     done();
-                });
+                };
+                zeroEx.token.subscribe(
+                    tokenAddress, TokenEvents.Approval, indexFilterValues, callback);
                 await zeroEx.token.setAllowanceAsync(tokenAddress, coinbase, addressWithoutFunds, allowanceAmount);
             })().catch(done);
         });
-        it('Outstanding subscriptions are cancelled when zeroEx.setProviderAsync called', (done: DoneCallback) => {
+        it('Outstanding subscriptions are cancelled when zeroEx.setProvider called', (done: DoneCallback) => {
             (async () => {
-                const eventSubscriptionToBeCancelled = await zeroEx.token.subscribeAsync(
-                    tokenAddress, TokenEvents.Transfer, subscriptionOpts, indexFilterValues);
-                eventSubscriptionToBeCancelled.watch((err: Error, event: ContractEvent) => {
+                const callbackNeverToBeCalled = (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
                     done(new Error('Expected this subscription to have been cancelled'));
-                });
-
-                const newProvider = web3Factory.getRpcProvider();
-                await zeroEx.setProviderAsync(newProvider);
-
-                const eventSubscriptionToStay = await zeroEx.token.subscribeAsync(
-                    tokenAddress, TokenEvents.Transfer, subscriptionOpts, indexFilterValues);
-                eventSubscriptionToStay.watch((err: Error, event: ContractEvent) => {
-                    expect(err).to.be.null();
-                    expect(event).to.not.be.undefined();
+                };
+                zeroEx.token.subscribe(
+                    tokenAddress, TokenEvents.Transfer, indexFilterValues, callbackNeverToBeCalled,
+                );
+                const callbackToBeCalled = (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
                     done();
-                });
+                };
+                const newProvider = web3Factory.getRpcProvider();
+                zeroEx.setProvider(newProvider, constants.TESTRPC_NETWORK_ID);
+                zeroEx.token.subscribe(
+                    tokenAddress, TokenEvents.Transfer, indexFilterValues, callbackToBeCalled,
+                );
                 await zeroEx.token.transferAsync(tokenAddress, coinbase, addressWithoutFunds, transferAmount);
             })().catch(done);
         });
-        it('Should stop watch for events when stopWatchingAsync called on the eventEmitter', (done: DoneCallback) => {
+        it('Should cancel subscription when unsubscribe called', (done: DoneCallback) => {
             (async () => {
-                const eventSubscriptionToBeStopped = await zeroEx.token.subscribeAsync(
-                    tokenAddress, TokenEvents.Transfer, subscriptionOpts, indexFilterValues);
-                eventSubscriptionToBeStopped.watch((err: Error, event: ContractEvent) => {
-                    done(new Error('Expected this subscription to have been stopped'));
-                });
-                await eventSubscriptionToBeStopped.stopWatchingAsync();
+                const callbackNeverToBeCalled = (err: Error, logEvent: DecodedLogEvent<ApprovalContractEventArgs>) => {
+                    done(new Error('Expected this subscription to have been cancelled'));
+                };
+                const subscriptionToken = zeroEx.token.subscribe(
+                    tokenAddress, TokenEvents.Transfer, indexFilterValues, callbackNeverToBeCalled);
+                zeroEx.token.unsubscribe(subscriptionToken);
                 await zeroEx.token.transferAsync(tokenAddress, coinbase, addressWithoutFunds, transferAmount);
                 done();
             })().catch(done);
         });
-        it('Should wrap all event args BigNumber instances in a newer version of BigNumber', (done: DoneCallback) => {
-            (async () => {
-                const zeroExEvent = await zeroEx.token.subscribeAsync(
-                    tokenAddress, TokenEvents.Transfer, subscriptionOpts, indexFilterValues);
-                zeroExEvent.watch((err: Error, event: ContractEvent) => {
-                    const args = event.args as TransferContractEventArgs;
-                    expect(args._value.isBigNumber).to.be.true();
-                    done();
-                });
-                await zeroEx.token.transferAsync(tokenAddress, coinbase, addressWithoutFunds, transferAmount);
-            })().catch(done);
-        });
     });
     describe('#getLogsAsync', () => {
         let tokenAddress: string;
         let tokenTransferProxyAddress: string;
         const subscriptionOpts: SubscriptionOpts = {
-            fromBlock: 'earliest',
-            toBlock: 'latest',
+            fromBlock: 0,
+            toBlock: BlockParamLiteral.Latest,
         };
         let txHash: string;
-        before(async () => {
+        before(() => {
             const token = tokens[0];
             tokenAddress = token.address;
-            tokenTransferProxyAddress = await zeroEx.proxy.getContractAddressAsync();
+            tokenTransferProxyAddress = zeroEx.proxy.getContractAddress();
         });
         it('should get logs with decoded args emitted by Approval', async () => {
             txHash = await zeroEx.token.setUnlimitedProxyAllowanceAsync(tokenAddress, coinbase);
             await zeroEx.awaitTransactionMinedAsync(txHash);
             const eventName = TokenEvents.Approval;
             const indexFilterValues = {};
-            const logs = await zeroEx.token.getLogsAsync(
+            const logs = await zeroEx.token.getLogsAsync<ApprovalContractEventArgs>(
                 tokenAddress, eventName, subscriptionOpts, indexFilterValues,
             );
             expect(logs).to.have.length(1);
+            const args = logs[0].args;
             expect(logs[0].event).to.be.equal(eventName);
-            expect(logs[0].args._owner).to.be.equal(coinbase);
-            expect(logs[0].args._spender).to.be.equal(tokenTransferProxyAddress);
-            expect(logs[0].args._value).to.be.bignumber.equal(zeroEx.token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS);
+            expect(args._owner).to.be.equal(coinbase);
+            expect(args._spender).to.be.equal(tokenTransferProxyAddress);
+            expect(args._value).to.be.bignumber.equal(zeroEx.token.UNLIMITED_ALLOWANCE_IN_BASE_UNITS);
         });
         it('should only get the logs with the correct event name', async () => {
             txHash = await zeroEx.token.setUnlimitedProxyAllowanceAsync(tokenAddress, coinbase);
@@ -482,11 +477,12 @@ describe('TokenWrapper', () => {
             const indexFilterValues = {
                 _owner: coinbase,
             };
-            const logs = await zeroEx.token.getLogsAsync(
+            const logs = await zeroEx.token.getLogsAsync<ApprovalContractEventArgs>(
                 tokenAddress, eventName, subscriptionOpts, indexFilterValues,
             );
             expect(logs).to.have.length(1);
-            expect(logs[0].args._owner).to.be.equal(coinbase);
+            const args = logs[0].args;
+            expect(args._owner).to.be.equal(coinbase);
         });
     });
 });

packages/0x.js/test/utils/blockchain_lifecycle.ts

@@ -0,0 +1,26 @@
+import {RPC} from './rpc';
+
+export class BlockchainLifecycle {
+    private rpc: RPC;
+    private snapshotIdsStack: number[];
+    constructor() {
+        this.rpc = new RPC();
+        this.snapshotIdsStack = [];
+    }
+    // TODO: In order to run these tests on an actual node, we should check if we are running against
+    // TestRPC, if so, use snapshots, otherwise re-deploy contracts before every test
+    public async startAsync(): Promise<void> {
+        const snapshotId = await this.rpc.takeSnapshotAsync();
+        this.snapshotIdsStack.push(snapshotId);
+    }
+    public async revertAsync(): Promise<void> {
+        const snapshotId = this.snapshotIdsStack.pop() as number;
+        const didRevert = await this.rpc.revertSnapshotAsync(snapshotId);
+        if (!didRevert) {
+            throw new Error(`Snapshot with id #${snapshotId} failed to revert`);
+        }
+    }
+    public async mineABlock(): Promise<void> {
+        await this.rpc.mineBlockAsync();
+    }
+}

packages/0x.js/test/utils/chai_setup.ts

@@ -1,7 +1,7 @@
 import * as chai from 'chai';
-import * as dirtyChai from 'dirty-chai';
-import ChaiBigNumber = require('chai-bignumber');
 import chaiAsPromised = require('chai-as-promised');
+import ChaiBigNumber = require('chai-bignumber');
+import * as dirtyChai from 'dirty-chai';
 
 export const chaiSetup = {
     configure() {

packages/0x.js/test/utils/constants.ts

@@ -2,7 +2,11 @@ export const constants = {
     NULL_ADDRESS: '0x0000000000000000000000000000000000000000',
     RPC_HOST: 'localhost',
     RPC_PORT: 8545,
+    ROPSTEN_NETWORK_ID: 3,
+    KOVAN_NETWORK_ID: 42,
     TESTRPC_NETWORK_ID: 50,
     KOVAN_RPC_URL: 'https://kovan.infura.io',
     ROPSTEN_RPC_URL: 'https://ropsten.infura.io',
+    ZRX_DECIMALS: 18,
+    GAS_ESTIMATE: 500000,
 };

packages/0x.js/test/utils/fill_scenarios.ts

@@ -1,6 +1,8 @@
-import * as BigNumber from 'bignumber.js';
-import {ZeroEx, Token, SignedOrder} from '../../src';
+import BigNumber from 'bignumber.js';
+
+import {SignedOrder, Token, ZeroEx} from '../../src';
 import {orderFactory} from '../utils/order_factory';
+
 import {constants} from './constants';
 
 export class FillScenarios {
@@ -21,8 +23,8 @@ export class FillScenarios {
     }
     public async createFillableSignedOrderAsync(makerTokenAddress: string, takerTokenAddress: string,
                                                 makerAddress: string, takerAddress: string,
-                                                fillableAmount: BigNumber.BigNumber,
-                                                expirationUnixTimestampSec?: BigNumber.BigNumber):
+                                                fillableAmount: BigNumber,
+                                                expirationUnixTimestampSec?: BigNumber):
                                            Promise<SignedOrder> {
         return this.createAsymmetricFillableSignedOrderAsync(
             makerTokenAddress, takerTokenAddress, makerAddress, takerAddress,
@@ -31,10 +33,10 @@ export class FillScenarios {
     }
     public async createFillableSignedOrderWithFeesAsync(
         makerTokenAddress: string, takerTokenAddress: string,
-        makerFee: BigNumber.BigNumber, takerFee: BigNumber.BigNumber,
+        makerFee: BigNumber, takerFee: BigNumber,
         makerAddress: string, takerAddress: string,
-        fillableAmount: BigNumber.BigNumber,
-        feeRecepient: string, expirationUnixTimestampSec?: BigNumber.BigNumber,
+        fillableAmount: BigNumber,
+        feeRecepient: string, expirationUnixTimestampSec?: BigNumber,
     ): Promise<SignedOrder> {
         return this.createAsymmetricFillableSignedOrderWithFeesAsync(
             makerTokenAddress, takerTokenAddress, makerFee, takerFee, makerAddress, takerAddress,
@@ -43,8 +45,8 @@ export class FillScenarios {
     }
     public async createAsymmetricFillableSignedOrderAsync(
         makerTokenAddress: string, takerTokenAddress: string, makerAddress: string, takerAddress: string,
-        makerFillableAmount: BigNumber.BigNumber, takerFillableAmount: BigNumber.BigNumber,
-        expirationUnixTimestampSec?: BigNumber.BigNumber): Promise<SignedOrder> {
+        makerFillableAmount: BigNumber, takerFillableAmount: BigNumber,
+        expirationUnixTimestampSec?: BigNumber): Promise<SignedOrder> {
         const makerFee = new BigNumber(0);
         const takerFee = new BigNumber(0);
         const feeRecepient = constants.NULL_ADDRESS;
@@ -54,8 +56,8 @@ export class FillScenarios {
         );
     }
     public async createPartiallyFilledSignedOrderAsync(makerTokenAddress: string, takerTokenAddress: string,
-                                                       takerAddress: string, fillableAmount: BigNumber.BigNumber,
-                                                       partialFillAmount: BigNumber.BigNumber) {
+                                                       takerAddress: string, fillableAmount: BigNumber,
+                                                       partialFillAmount: BigNumber) {
         const [makerAddress] = this.userAddresses;
         const signedOrder = await this.createAsymmetricFillableSignedOrderAsync(
             makerTokenAddress, takerTokenAddress, makerAddress, takerAddress,
@@ -69,10 +71,10 @@ export class FillScenarios {
     }
     private async createAsymmetricFillableSignedOrderWithFeesAsync(
         makerTokenAddress: string, takerTokenAddress: string,
-        makerFee: BigNumber.BigNumber, takerFee: BigNumber.BigNumber,
+        makerFee: BigNumber, takerFee: BigNumber,
         makerAddress: string, takerAddress: string,
-        makerFillableAmount: BigNumber.BigNumber, takerFillableAmount: BigNumber.BigNumber,
-        feeRecepient: string, expirationUnixTimestampSec?: BigNumber.BigNumber): Promise<SignedOrder> {
+        makerFillableAmount: BigNumber, takerFillableAmount: BigNumber,
+        feeRecepient: string, expirationUnixTimestampSec?: BigNumber): Promise<SignedOrder> {
 
         await Promise.all([
             this.increaseBalanceAndAllowanceAsync(makerTokenAddress, makerAddress, makerFillableAmount),
@@ -90,8 +92,8 @@ export class FillScenarios {
         return signedOrder;
     }
     private async increaseBalanceAndAllowanceAsync(
-        tokenAddress: string, address: string, amount: BigNumber.BigNumber): Promise<void> {
-        if (amount.isZero()) {
+        tokenAddress: string, address: string, amount: BigNumber): Promise<void> {
+        if (amount.isZero() || address === ZeroEx.NULL_ADDRESS) {
             return; // noop
         }
         await Promise.all([
@@ -100,11 +102,11 @@ export class FillScenarios {
         ]);
     }
     private async increaseBalanceAsync(
-        tokenAddress: string, address: string, amount: BigNumber.BigNumber): Promise<void> {
+        tokenAddress: string, address: string, amount: BigNumber): Promise<void> {
         await this.zeroEx.token.transferAsync(tokenAddress, this.coinbase, address, amount);
     }
     private async increaseAllowanceAsync(
-        tokenAddress: string, address: string, amount: BigNumber.BigNumber): Promise<void> {
+        tokenAddress: string, address: string, amount: BigNumber): Promise<void> {
         const oldMakerAllowance = await this.zeroEx.token.getProxyAllowanceAsync(tokenAddress, address);
         const newMakerAllowance = oldMakerAllowance.plus(amount);
         await this.zeroEx.token.setProxyAllowanceAsync(

packages/0x.js/test/utils/order_factory.ts

@@ -1,25 +1,26 @@
+import BigNumber from 'bignumber.js';
 import * as _ from 'lodash';
-import * as BigNumber from 'bignumber.js';
-import {ZeroEx, SignedOrder} from '../../src';
+
+import {SignedOrder, ZeroEx} from '../../src';
 
 export const orderFactory = {
     async createSignedOrderAsync(
         zeroEx: ZeroEx,
         maker: string,
         taker: string,
-        makerFee: BigNumber.BigNumber,
-        takerFee: BigNumber.BigNumber,
-        makerTokenAmount: BigNumber.BigNumber,
+        makerFee: BigNumber,
+        takerFee: BigNumber,
+        makerTokenAmount: BigNumber,
         makerTokenAddress: string,
-        takerTokenAmount: BigNumber.BigNumber,
+        takerTokenAmount: BigNumber,
         takerTokenAddress: string,
         exchangeContractAddress: string,
         feeRecipient: string,
-        expirationUnixTimestampSec?: BigNumber.BigNumber): Promise<SignedOrder> {
+        expirationUnixTimestampSecIfExists?: BigNumber): Promise<SignedOrder> {
         const defaultExpirationUnixTimestampSec = new BigNumber(2524604400); // Close to infinite
-        expirationUnixTimestampSec = _.isUndefined(expirationUnixTimestampSec) ?
+        const expirationUnixTimestampSec = _.isUndefined(expirationUnixTimestampSecIfExists) ?
             defaultExpirationUnixTimestampSec :
-            expirationUnixTimestampSec;
+            expirationUnixTimestampSecIfExists;
         const order = {
             maker,
             taker,

packages/0x.js/test/utils/report_callback_errors.ts

@@ -0,0 +1,14 @@
+import { DoneCallback } from '../../src/types';
+
+export const reportCallbackErrors = (done: DoneCallback) => {
+    return (f: (...args: any[]) => void) => {
+        const wrapped = async (...args: any[]) => {
+            try {
+                f(...args);
+            } catch (err) {
+                done(err);
+            }
+        };
+        return wrapped;
+    };
+};

packages/0x.js/test/utils/rpc.ts

@@ -1,5 +1,6 @@
 import * as ethUtil from 'ethereumjs-util';
 import * as request from 'request-promise-native';
+
 import {constants} from './constants';
 
 export class RPC {
@@ -26,6 +27,12 @@ export class RPC {
         const didRevert = await this.sendAsync(payload);
         return didRevert;
     }
+    public async mineBlockAsync(): Promise<void> {
+        const method = 'evm_mine';
+        const params: any[] = [];
+        const payload = this.toPayload(method, params);
+        await this.sendAsync(payload);
+    }
     private toPayload(method: string, params: any[] = []): string {
         const payload = JSON.stringify({
             id: this.id,
@@ -41,7 +48,7 @@ export class RPC {
             uri: `http://${this.host}:${this.port}`,
             body: payload,
             headers: {
-                'content-type': 'application/json'
+                'content-type': 'application/json',
             },
         };
         const bodyString = await request(opts);

packages/0x.js/test/utils/subproviders/empty_wallet_subprovider.ts

@@ -1,12 +1,13 @@
-import * as Web3 from 'web3';
-import {JSONRPCPayload} from '../types';
+import {JSONRPCPayload} from '../../../src/types';
 
 /*
  * This class implements the web3-provider-engine subprovider interface and returns
  * that the provider has no addresses when queried.
  * Source: https://github.com/MetaMask/provider-engine/blob/master/subproviders/subprovider.js
  */
-export class EmptyWalletSubProvider {
+export class EmptyWalletSubprovider {
+    // This method needs to be here to satisfy the interface but linter wants it to be static.
+    // tslint:disable-next-line:prefer-function-over-method
     public handleRequest(payload: JSONRPCPayload, next: () => void, end: (err: Error|null, result: any) => void) {
         switch (payload.method) {
             case 'eth_accounts':
@@ -19,6 +20,7 @@ export class EmptyWalletSubProvider {
         }
     }
     // Required to implement this method despite not needing it for this subprovider
+    // tslint:disable-next-line:prefer-function-over-method
     public setEngine(engine: any) {
         // noop
     }

packages/0x.js/test/utils/subproviders/fake_gas_estimate_subprovider.ts

@@ -0,0 +1,34 @@
+import {JSONRPCPayload} from '../../../src/types';
+
+/*
+ * This class implements the web3-provider-engine subprovider interface and returns
+ * the constant gas estimate when queried.
+ * HACK: We need this so that our tests don't use testrpc gas estimation which sometimes kills the node.
+ * Source: https://github.com/trufflesuite/ganache-cli/issues/417
+ * Source: https://github.com/trufflesuite/ganache-cli/issues/437
+ * Source: https://github.com/MetaMask/provider-engine/blob/master/subproviders/subprovider.js
+ */
+export class FakeGasEstimateSubprovider {
+    private constantGasAmount: number;
+    constructor(constantGasAmount: number) {
+        this.constantGasAmount = constantGasAmount;
+    }
+    // This method needs to be here to satisfy the interface but linter wants it to be static.
+    // tslint:disable-next-line:prefer-function-over-method
+    public handleRequest(payload: JSONRPCPayload, next: () => void, end: (err: Error|null, result: any) => void) {
+        switch (payload.method) {
+            case 'eth_estimateGas':
+                end(null, this.constantGasAmount);
+                return;
+
+            default:
+                next();
+                return;
+        }
+    }
+    // Required to implement this method despite not needing it for this subprovider
+    // tslint:disable-next-line:prefer-function-over-method
+    public setEngine(engine: any) {
+        // noop
+    }
+}

packages/0x.js/test/utils/token_utils.ts

@@ -1,5 +1,6 @@
 import * as _ from 'lodash';
-import {Token, InternalZeroExError} from '../../src/types';
+
+import {InternalZeroExError, Token} from '../../src/types';
 
 const PROTOCOL_TOKEN_SYMBOL = 'ZRX';
 

packages/0x.js/test/utils/web3_factory.ts

@@ -3,11 +3,14 @@
 // we are not running in a browser env.
 // Filed issue: https://github.com/ethereum/web3.js/issues/844
 (global as any).XMLHttpRequest = undefined;
+import * as Web3 from 'web3';
 import ProviderEngine = require('web3-provider-engine');
 import RpcSubprovider = require('web3-provider-engine/subproviders/rpc');
-import * as Web3 from 'web3';
+
+import {EmptyWalletSubprovider} from './subproviders/empty_wallet_subprovider';
+import {FakeGasEstimateSubprovider} from './subproviders/fake_gas_estimate_subprovider';
+
 import {constants} from './constants';
-import {EmptyWalletSubProvider} from '../../src/subproviders/empty_wallet_subprovider';
 
 export const web3Factory = {
     create(hasAddresses: boolean = true): Web3 {
@@ -20,8 +23,9 @@ export const web3Factory = {
         const provider = new ProviderEngine();
         const rpcUrl = `http://${constants.RPC_HOST}:${constants.RPC_PORT}`;
         if (!hasAddresses) {
-            provider.addProvider(new EmptyWalletSubProvider());
+            provider.addProvider(new EmptyWalletSubprovider());
         }
+        provider.addProvider(new FakeGasEstimateSubprovider(constants.GAS_ESTIMATE));
         provider.addProvider(new RpcSubprovider({
             rpcUrl,
         }));

packages/0x.js/tsconfig.json

@@ -13,10 +13,10 @@
   "include": [
     "./src/**/*",
     "./test/**/*",
-    "./node_modules/types-bn/index.d.ts",
-    "./node_modules/types-ethereumjs-util/index.d.ts",
-    "./node_modules/web3-typescript-typings/index.d.ts",
-    "./node_modules/chai-typescript-typings/index.d.ts",
-    "./node_modules/chai-as-promised-typescript-typings/index.d.ts"
+    "../../node_modules/types-bn/index.d.ts",
+    "../../node_modules/types-ethereumjs-util/index.d.ts",
+    "../../node_modules/web3-typescript-typings/index.d.ts",
+    "../../node_modules/chai-typescript-typings/index.d.ts",
+    "../../node_modules/chai-as-promised-typescript-typings/index.d.ts"
   ]
 }

packages/0x.js/tslint.json

@@ -0,0 +1,5 @@
+{
+  "extends": [
+    "@0xproject/tslint-config"
+  ]
+}

packages/assert/CHANGELOG.md

@@ -0,0 +1,6 @@
+# CHANGELOG
+
+v0.0.4 - _Nov. 14, 2017_
+------------------------
+    * Re-publish Assert previously published under NPM package @0xproject/0x-assert
+    * Added assertion isValidBaseUnitAmount which checks both that the value is a valid bigNumber and that it does not contain decimals.

packages/assert/README.md

@@ -0,0 +1,10 @@
+assert
+------
+
+Standard type and schema assertions to be used across all 0x projects and packages
+
+## Install
+
+```bash
+npm install @0xproject/assert --save
+```

packages/assert/package.json

@@ -0,0 +1,46 @@
+{
+  "name": "@0xproject/assert",
+  "version": "0.0.5",
+  "description": "Provides a standard way of performing type and schema validation across 0x projects",
+  "main": "lib/src/index.js",
+  "types": "lib/src/index.d.ts",
+  "scripts": {
+    "build": "tsc",
+    "clean": "shx rm -rf _bundles lib test_temp",
+    "lint": "tslint --project . 'src/**/*.ts' 'test/**/*.ts'",
+    "run_mocha": "mocha lib/test/**/*_test.js",
+    "prepublishOnly": "run-p build",
+    "test": "run-s clean build run_mocha",
+    "test:circleci": "yarn test"
+  },
+  "license": "Apache-2.0",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/0xProject/0x.js.git"
+  },
+  "bugs": {
+    "url": "https://github.com/0xProject/0x.js/issues"
+  },
+  "homepage": "https://github.com/0xProject/0x.js/packages/assert/README.md",
+  "devDependencies": {
+    "@0xproject/tslint-config": "^0.1.1",
+    "@types/lodash": "^4.14.78",
+    "@types/mocha": "^2.2.42",
+    "@types/valid-url": "^1.0.2",
+    "chai": "^4.0.1",
+    "chai-typescript-typings": "^0.0.1",
+    "dirty-chai": "^2.0.1",
+    "mocha": "^4.0.1",
+    "npm-run-all": "^4.1.1",
+    "shx": "^0.2.2",
+    "tslint": "5.8.0",
+    "typescript": "^2.4.2"
+  },
+  "dependencies": {
+    "@0xproject/json-schemas": "^0.6.8",
+    "bignumber.js": "~4.1.0",
+    "ethereum-address": "^0.0.4",
+    "lodash": "^4.17.4",
+    "valid-url": "^1.0.9"
+  }
+}

packages/assert/scripts/postpublish.js

@@ -0,0 +1,14 @@
+const postpublish_utils = require('../../../scripts/postpublish_utils');
+const packageJSON = require('../package.json');
+
+const subPackageName = packageJSON.name;
+
+postpublish_utils.getLatestTagAndVersionAsync(subPackageName)
+    .then(function(result) {
+        const releaseName = postpublish_utils.getReleaseName(subPackageName, result.version);
+        const assets = [];
+        return postpublish_utils.publishReleaseNotes(result.tag, releaseName, assets);
+    })
+    .catch (function(err) {
+        throw err;
+    });

packages/assert/src/globals.d.ts

@@ -0,0 +1,5 @@
+declare module 'dirty-chai';
+
+declare module 'ethereum-address' {
+    const isAddress: (arg: any) => boolean;
+}

packages/assert/src/index.ts

@@ -1,31 +1,43 @@
+import {
+    Schema,
+    SchemaValidator,
+} from '@0xproject/json-schemas';
+import BigNumber from 'bignumber.js';
+import * as ethereum_address from 'ethereum-address';
 import * as _ from 'lodash';
-import * as BigNumber from 'bignumber.js';
-import * as Web3 from 'web3';
-import {Web3Wrapper} from '../web3_wrapper';
-import {SchemaValidator, Schema} from '0x-json-schemas';
+import * as validUrl from 'valid-url';
 
 const HEX_REGEX = /^0x[0-9A-F]*$/i;
 
 export const assert = {
-    isBigNumber(variableName: string, value: BigNumber.BigNumber): void {
-        const isBigNumber = _.isObject(value) && value.isBigNumber;
+    isBigNumber(variableName: string, value: BigNumber): void {
+        const isBigNumber = _.isObject(value) && (value as any).isBigNumber;
         this.assert(isBigNumber, this.typeAssertionMessage(variableName, 'BigNumber', value));
     },
+    isValidBaseUnitAmount(variableName: string, value: BigNumber) {
+        assert.isBigNumber(variableName, value);
+        const hasDecimals = value.decimalPlaces() !== 0;
+        this.assert(
+            !hasDecimals, `${variableName} should be in baseUnits (no decimals), found value: ${value.toNumber()}`,
+        );
+    },
     isUndefined(value: any, variableName?: string): void {
         this.assert(_.isUndefined(value), this.typeAssertionMessage(variableName, 'undefined', value));
     },
     isString(variableName: string, value: string): void {
         this.assert(_.isString(value), this.typeAssertionMessage(variableName, 'string', value));
     },
+    isFunction(variableName: string, value: any): void {
+        this.assert(_.isFunction(value), this.typeAssertionMessage(variableName, 'function', value));
+    },
     isHexString(variableName: string, value: string): void {
         this.assert(_.isString(value) && HEX_REGEX.test(value),
             this.typeAssertionMessage(variableName, 'HexString', value));
     },
     isETHAddressHex(variableName: string, value: string): void {
-        const web3 = new Web3();
-        this.assert(web3.isAddress(value), this.typeAssertionMessage(variableName, 'ETHAddressHex', value));
+        this.assert(ethereum_address.isAddress(value), this.typeAssertionMessage(variableName, 'ETHAddressHex', value));
         this.assert(
-            web3.isAddress(value) && !web3.isChecksumAddress(value),
+            ethereum_address.isAddress(value) && value.toLowerCase() === value,
             `Checksummed addresses are not supported. Convert ${variableName} to lower case before passing`,
         );
     },
@@ -40,18 +52,6 @@ export const assert = {
             `Expected ${variableName} to be one of: ${enumValuesAsString}, encountered: ${value}`,
         );
     },
-    async isSenderAddressAsync(variableName: string, senderAddressHex: string,
-                               web3Wrapper: Web3Wrapper): Promise<void> {
-        assert.isETHAddressHex(variableName, senderAddressHex);
-        const isSenderAddressAvailable = await web3Wrapper.isSenderAddressAvailableAsync(senderAddressHex);
-        assert.assert(isSenderAddressAvailable,
-            `Specified ${variableName} ${senderAddressHex} isn't available through the supplied web3 provider`,
-        );
-    },
-    async isUserAddressAvailableAsync(web3Wrapper: Web3Wrapper): Promise<void> {
-        const availableAddresses = await web3Wrapper.getAvailableAddressesAsync();
-        this.assert(!_.isEmpty(availableAddresses), 'No addresses were available on the provided web3 provider');
-    },
     hasAtMostOneUniqueValue(value: any[], errMsg: string): void {
         this.assert(_.uniq(value).length <= 1, errMsg);
     },
@@ -61,8 +61,8 @@ export const assert = {
     isBoolean(variableName: string, value: boolean): void {
         this.assert(_.isBoolean(value), this.typeAssertionMessage(variableName, 'boolean', value));
     },
-    isWeb3Provider(variableName: string, value: Web3.Provider): void {
-        const isWeb3Provider = _.isFunction((value as any).send) || _.isFunction((value as any).sendAsync);
+    isWeb3Provider(variableName: string, value: any): void {
+        const isWeb3Provider = _.isFunction((value).send) || _.isFunction((value).sendAsync);
         this.assert(isWeb3Provider, this.typeAssertionMessage(variableName, 'Web3.Provider', value));
     },
     doesConformToSchema(variableName: string, value: any, schema: Schema): void {
@@ -74,6 +74,14 @@ Encountered: ${JSON.stringify(value, null, '\t')}
 Validation errors: ${validationResult.errors.join(', ')}`;
         this.assert(!hasValidationErrors, msg);
     },
+    isHttpUrl(variableName: string, value: any): void {
+        const isValidUrl = validUrl.isWebUri(value);
+        this.assert(isValidUrl, this.typeAssertionMessage(variableName, 'http url', value));
+    },
+    isUri(variableName: string, value: any): void {
+        const isValidUri = validUrl.isUri(value);
+        this.assert(isValidUri, this.typeAssertionMessage(variableName, 'uri', value));
+    },
     assert(condition: boolean, message: string): void {
         if (!condition) {
             throw new Error(message);

packages/assert/test/assert_test.ts

@@ -0,0 +1,339 @@
+import {schemas} from '@0xproject/json-schemas';
+import {BigNumber} from 'bignumber.js';
+import * as chai from 'chai';
+import * as dirtyChai from 'dirty-chai';
+import 'mocha';
+
+import {assert} from '../src/index';
+
+chai.config.includeStack = true;
+chai.use(dirtyChai);
+const expect = chai.expect;
+
+describe('Assertions', () => {
+    const variableName = 'variable';
+    describe('#isBigNumber', () => {
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                new BigNumber(23),
+                new BigNumber('45'),
+            ];
+            validInputs.forEach(input => expect(assert.isBigNumber.bind(assert, variableName, input)).to.not.throw());
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                'test',
+                42,
+                false,
+                { random: 'test' },
+                undefined,
+            ];
+            invalidInputs.forEach(input => expect(assert.isBigNumber.bind(assert, variableName, input)).to.throw());
+        });
+    });
+    describe('#isUndefined', () => {
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                undefined,
+            ];
+            validInputs.forEach(input => expect(assert.isUndefined.bind(assert, input, variableName)).to.not.throw());
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                'test',
+                42,
+                false,
+                { random: 'test' },
+            ];
+            invalidInputs.forEach(input => expect(assert.isUndefined.bind(assert, input, variableName)).to.throw());
+        });
+    });
+    describe('#isString', () => {
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                'hello',
+                'goodbye',
+            ];
+            validInputs.forEach(input => expect(assert.isString.bind(assert, variableName, input)).to.not.throw());
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                42,
+                false,
+                { random: 'test' },
+                undefined,
+                new BigNumber(45),
+            ];
+            invalidInputs.forEach(input => expect(assert.isString.bind(assert, variableName, input)).to.throw());
+        });
+    });
+    describe('#isFunction', () => {
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                BigNumber,
+                assert.isString.bind(this),
+            ];
+            validInputs.forEach(input => expect(assert.isFunction.bind(assert, variableName, input)).to.not.throw());
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                42,
+                false,
+                { random: 'test' },
+                undefined,
+                new BigNumber(45),
+            ];
+            invalidInputs.forEach(input => expect(assert.isFunction.bind(assert, variableName, input)).to.throw());
+        });
+    });
+    describe('#isHexString', () => {
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                '0x61a3ed31B43c8780e905a260a35faefEc527be7516aa11c0256729b5b351bc33',
+                '0x40349190569279751135161d22529dc25add4f6069af05be04cacbda2ace2254',
+            ];
+            validInputs.forEach(input => expect(assert.isHexString.bind(assert, variableName, input)).to.not.throw());
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                42,
+                false,
+                { random: 'test' },
+                undefined,
+                new BigNumber(45),
+                '0x61a3ed31B43c8780e905a260a35faYfEc527be7516aa11c0256729b5b351bc33',
+            ];
+            invalidInputs.forEach(input => expect(assert.isHexString.bind(assert, variableName, input)).to.throw());
+        });
+    });
+    describe('#isETHAddressHex', () => {
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                '0x0000000000000000000000000000000000000000',
+                '0x6fffd0ae3f7d88c9b4925323f54c6e4b2918c5fd',
+                '0x12459c951127e0c374ff9105dda097662a027093',
+            ];
+            validInputs.forEach(input =>
+                expect(assert.isETHAddressHex.bind(assert, variableName, input)).to.not.throw(),
+            );
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                42,
+                false,
+                { random: 'test' },
+                undefined,
+                new BigNumber(45),
+                '0x6FFFd0ae3f7d88c9b4925323f54c6e4b2918c5fd',
+                '0x6FFFd0ae3f7d88c9b4925323f54c6e4',
+            ];
+            invalidInputs.forEach(input =>
+                expect(assert.isETHAddressHex.bind(assert, variableName, input)).to.throw(),
+            );
+        });
+    });
+    describe('#doesBelongToStringEnum', () => {
+        enum TestEnums {
+            Test1 = 'Test1',
+            Test2 = 'Test2',
+        }
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                TestEnums.Test1,
+                TestEnums.Test2,
+            ];
+            validInputs.forEach(input =>
+                expect(assert.doesBelongToStringEnum.bind(assert, variableName, input, TestEnums)).to.not.throw(),
+            );
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                42,
+                false,
+                { random: 'test' },
+                undefined,
+                new BigNumber(45),
+            ];
+            invalidInputs.forEach(input =>
+                expect(assert.doesBelongToStringEnum.bind(assert, variableName, input, TestEnums)).to.throw(),
+            );
+        });
+    });
+    describe('#hasAtMostOneUniqueValue', () => {
+        const errorMsg = 'more than one unique value';
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                ['hello'],
+                ['goodbye', 'goodbye', 'goodbye'],
+            ];
+            validInputs.forEach(input =>
+                expect(assert.hasAtMostOneUniqueValue.bind(assert, input, errorMsg)).to.not.throw(),
+            );
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                ['hello', 'goodbye'],
+                ['goodbye', 42, false, false],
+            ];
+            invalidInputs.forEach(input =>
+                expect(assert.hasAtMostOneUniqueValue.bind(assert, input, errorMsg)).to.throw(),
+            );
+        });
+    });
+    describe('#isNumber', () => {
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                42,
+                0,
+                21e+42,
+            ];
+            validInputs.forEach(input => expect(assert.isNumber.bind(assert, variableName, input)).to.not.throw());
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                false,
+                { random: 'test' },
+                undefined,
+                new BigNumber(45),
+            ];
+            invalidInputs.forEach(input => expect(assert.isNumber.bind(assert, variableName, input)).to.throw());
+        });
+    });
+    describe('#isBoolean', () => {
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                true,
+                false,
+            ];
+            validInputs.forEach(input => expect(assert.isBoolean.bind(assert, variableName, input)).to.not.throw());
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                42,
+                { random: 'test' },
+                undefined,
+                new BigNumber(45),
+            ];
+            invalidInputs.forEach(input => expect(assert.isBoolean.bind(assert, variableName, input)).to.throw());
+        });
+    });
+    describe('#isWeb3Provider', () => {
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                { send: () => 45 },
+                { sendAsync: () => 45 },
+            ];
+            validInputs.forEach(input =>
+                expect(assert.isWeb3Provider.bind(assert, variableName, input)).to.not.throw(),
+            );
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                42,
+                { random: 'test' },
+                undefined,
+                new BigNumber(45),
+            ];
+            invalidInputs.forEach(input =>
+                expect(assert.isWeb3Provider.bind(assert, variableName, input)).to.throw(),
+            );
+        });
+    });
+    describe('#doesConformToSchema', () => {
+        const schema = schemas.addressSchema;
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                '0x6fffd0ae3f7d88c9b4925323f54c6e4b2918c5fd',
+                '0x12459c951127e0c374ff9105dda097662a027093',
+            ];
+            validInputs.forEach(input =>
+                expect(assert.doesConformToSchema.bind(assert, variableName, input, schema)).to.not.throw(),
+            );
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                42,
+                { random: 'test' },
+                undefined,
+                new BigNumber(45),
+            ];
+            invalidInputs.forEach(input =>
+                expect(assert.doesConformToSchema.bind(assert, variableName, input, schema)).to.throw(),
+            );
+        });
+    });
+    describe('#isHttpUrl', () => {
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                'http://www.google.com',
+                'https://api.example-relayer.net',
+                'https://api.radarrelay.com/0x/v0/',
+                'https://zeroex.beta.radarrelay.com:8000/0x/v0/',
+            ];
+            validInputs.forEach(input =>
+                expect(assert.isHttpUrl.bind(assert, variableName, input)).to.not.throw(),
+            );
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                42,
+                { random: 'test' },
+                undefined,
+                new BigNumber(45),
+                'ws://www.api.example-relayer.net',
+                'www.google.com',
+                'api.example-relayer.net',
+                'user:password@api.example-relayer.net',
+                '//api.example-relayer.net',
+            ];
+            invalidInputs.forEach(input =>
+                expect(assert.isHttpUrl.bind(assert, variableName, input)).to.throw(),
+            );
+        });
+    });
+    describe('#isUri', () => {
+        it('should not throw for valid input', () => {
+            const validInputs = [
+                'http://www.google.com',
+                'https://api.example-relayer.net',
+                'https://api.radarrelay.com/0x/v0/',
+                'https://zeroex.beta.radarrelay.com:8000/0x/v0/',
+                'ws://www.api.example-relayer.net',
+                'wss://www.api.example-relayer.net',
+                'user:password@api.example-relayer.net',
+            ];
+            validInputs.forEach(input =>
+                expect(assert.isUri.bind(assert, variableName, input)).to.not.throw(),
+            );
+        });
+        it('should throw for invalid input', () => {
+            const invalidInputs = [
+                42,
+                { random: 'test' },
+                undefined,
+                new BigNumber(45),
+                'www.google.com',
+                'api.example-relayer.net',
+                '//api.example-relayer.net',
+            ];
+            invalidInputs.forEach(input =>
+                expect(assert.isUri.bind(assert, variableName, input)).to.throw(),
+            );
+        });
+    });
+    describe('#assert', () => {
+        const assertMessage = 'assert not satisfied';
+        it('should not throw for valid input', () => {
+            expect(assert.assert.bind(assert, true, assertMessage)).to.not.throw();
+        });
+        it('should throw for invalid input', () => {
+            expect(assert.assert.bind(assert, false, assertMessage)).to.throw();
+        });
+    });
+    describe('#typeAssertionMessage', () => {
+        it('should render correct message', () => {
+            expect(assert.typeAssertionMessage('variable', 'string', 'number'))
+            .to.equal(`Expected variable to be of type string, encountered: number`);
+        });
+    });
+});

packages/assert/tsconfig.json

@@ -0,0 +1,18 @@
+{
+  "compilerOptions": {
+    "module": "commonjs",
+    "target": "es5",
+    "lib": [ "es2017", "dom"],
+    "outDir": "lib",
+    "sourceMap": true,
+    "declaration": true,
+    "noImplicitAny": true,
+    "strictNullChecks": true
+  },
+  "include": [
+    "./src/**/*",
+    "./test/**/*",
+    "../../node_modules/chai-typescript-typings/index.d.ts",
+    "../../node_modules/web3-typescript-typings/index.d.ts"
+  ]
+}

packages/assert/tslint.json

@@ -0,0 +1,5 @@
+{
+  "extends": [
+    "@0xproject/tslint-config"
+  ]
+}

packages/connect/CHANGELOG.md

@@ -0,0 +1,5 @@
+# CHANGELOG
+
+v0.1.0 - _November 22, 2017_
+------------------------
+    * Provide a HttpClient class for interacting with standard relayer api compliant HTTP urls

packages/connect/README.md

@@ -0,0 +1 @@
+This repository contains a Javascript library that makes it easy to interact with Relayers that conform to the [Standard Relayer API](https://github.com/0xProject/standard-relayer-api)

packages/connect/package.json

@@ -0,0 +1,70 @@
+{
+  "name": "@0xproject/connect",
+  "version": "0.1.0",
+  "description": "A javascript library for interacting with the standard relayer api",
+  "keywords": [
+    "connect",
+    "0xproject",
+    "ethereum",
+    "tokens",
+    "exchange"
+  ],
+  "main": "lib/src/index.js",
+  "types": "lib/src/index.d.ts",
+  "scripts": {
+    "build": "tsc",
+    "clean": "shx rm -rf _bundles lib test_temp",
+    "docs:json": "typedoc --excludePrivate --excludeExternals --target ES5 --json $JSON_FILE_PATH $PROJECT_DIR",
+    "upload_docs_json": "aws s3 cp generated_docs/index.json $S3_URL --profile 0xproject --grants read=uri=http://acs.amazonaws.com/groups/global/AllUsers --content-type application/json",
+    "copy_test_fixtures": "copyfiles -u 2 './test/fixtures/**/*.json' ./lib/test/fixtures",
+    "lint": "tslint --project . 'src/**/*.ts' 'test/**/*.ts'",
+    "run_mocha": "mocha lib/test/**/*_test.js",
+    "test": "run-s clean build copy_test_fixtures run_mocha",
+    "test:circleci": "yarn test"
+  },
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/0xProject/0x.js.git"
+  },
+  "author": "Brandon Millman",
+  "license": "Apache-2.0",
+  "engines": {
+    "node": ">=6.0.0"
+  },
+  "bugs": {
+    "url": "https://github.com/0xProject/0x.js/issues"
+  },
+  "homepage": "https://github.com/0xProject/0x.js/packages/connect/README.md",
+  "dependencies": {
+    "0x.js": "^0.26.1",
+    "@0xproject/assert": "^0.0.5",
+    "@0xproject/json-schemas": "^0.6.8",
+    "bignumber.js": "~4.1.0",
+    "isomorphic-fetch": "^2.2.1",
+    "lodash": "^4.17.4",
+    "query-string": "^5.0.1",
+    "websocket": "^1.0.25"
+  },
+  "devDependencies": {
+    "@0xproject/tslint-config": "^0.1.1",
+    "@types/fetch-mock": "^5.12.1",
+    "@types/lodash": "^4.14.77",
+    "@types/mocha": "^2.2.42",
+    "@types/query-string": "^5.0.1",
+    "@types/websocket": "^0.0.34",
+    "chai": "^4.0.1",
+    "chai-as-promised": "^7.1.0",
+    "chai-as-promised-typescript-typings": "0.0.3",
+    "chai-typescript-typings": "^0.0.1",
+    "copyfiles": "^1.2.0",
+    "dirty-chai": "^2.0.1",
+    "fetch-mock": "^5.13.1",
+    "mocha": "^4.0.0",
+    "npm-run-all": "^4.0.2",
+    "shx": "^0.2.2",
+    "tslint": "5.8.0",
+    "typedoc": "~0.8.0",
+    "typescript": "~2.6.1",
+    "web3-typescript-typings": "^0.7.1"
+  }
+}

packages/connect/scripts/postpublish.js

@@ -0,0 +1,40 @@
+const execAsync = require('async-child-process').execAsync;
+const postpublish_utils = require('../../../scripts/postpublish_utils');
+const packageJSON = require('../package.json');
+
+const cwd = __dirname + '/..';
+const subPackageName = packageJSON.name;
+const S3BucketPath = 's3://connect-docs-jsons/';
+
+let tag;
+let version;
+postpublish_utils.getLatestTagAndVersionAsync(subPackageName)
+    .then(function(result) {
+        tag = result.tag;
+        version = result.version;
+         const releaseName = postpublish_utils.getReleaseName(subPackageName, version);
+         return postpublish_utils.publishReleaseNotes(tag, releaseName);
+    })
+    .then(function(release) {
+        console.log('POSTPUBLISH: Release successful, generating docs...');
+        const jsonFilePath = __dirname + '/../' + postpublish_utils.generatedDocsDirectoryName + '/index.json';
+        return execAsync(
+            'JSON_FILE_PATH=' + jsonFilePath + ' PROJECT_DIR=' + __dirname + '/.. yarn docs:json',
+            {
+                cwd,
+            }
+        );
+    })
+    .then(function(result) {
+        if (result.stderr !== '') {
+            throw new Error(result.stderr);
+        }
+        const fileName = 'v' + version + '.json';
+        console.log('POSTPUBLISH: Doc generation successful, uploading docs... as ', fileName);
+        const s3Url = S3BucketPath + fileName;
+        return execAsync('S3_URL=' + s3Url + ' yarn upload_docs_json', {
+            cwd,
+        });
+    }).catch (function(err) {
+        throw err;
+    });

packages/connect/src/globals.d.ts

@@ -0,0 +1,6 @@
+declare module 'dirty-chai';
+
+declare module '*.json' {
+    const value: any;
+    export default value;
+}

packages/connect/src/http_client.ts

@@ -0,0 +1,171 @@
+import {SignedOrder} from '0x.js';
+import {assert} from '@0xproject/assert';
+import {schemas} from '@0xproject/json-schemas';
+import {BigNumber} from 'bignumber.js';
+import 'isomorphic-fetch';
+import * as _ from 'lodash';
+import * as queryString from 'query-string';
+
+import {schemas as clientSchemas} from './schemas/schemas';
+import {
+    Client,
+    FeesRequest,
+    FeesResponse,
+    HttpRequestOptions,
+    HttpRequestType,
+    OrderbookRequest,
+    OrderbookResponse,
+    OrdersRequest,
+    TokenPairsItem,
+    TokenPairsRequest,
+} from './types';
+import {typeConverters} from './utils/type_converters';
+
+// TODO: move this and bigNumberConfigs in the 0x.js package into one place
+BigNumber.config({
+    EXPONENTIAL_AT: 1000,
+});
+
+/**
+ * This class includes all the functionality related to interacting with a set of HTTP endpoints
+ * that implement the standard relayer API v0
+ */
+export class HttpClient implements Client {
+    private apiEndpointUrl: string;
+    /**
+     * Instantiates a new HttpClient instance
+     * @param   url    The base url for making API calls
+     * @return  An instance of HttpClient
+     */
+    constructor(url: string) {
+        assert.isHttpUrl('url', url);
+        this.apiEndpointUrl = url;
+    }
+    /**
+     * Retrieve token pair info from the API
+     * @param   request     A TokenPairsRequest instance describing specific token information
+     *                      to retrieve
+     * @return  The resulting TokenPairsItems that match the request
+     */
+    public async getTokenPairsAsync(request?: TokenPairsRequest): Promise<TokenPairsItem[]> {
+        if (!_.isUndefined(request)) {
+            assert.doesConformToSchema('request', request, clientSchemas.relayerTokenPairsRequestSchema);
+        }
+        const requestOpts = {
+            params: request,
+        };
+        const tokenPairs = await this._requestAsync('/token_pairs', HttpRequestType.Get, requestOpts);
+        assert.doesConformToSchema(
+            'tokenPairs', tokenPairs, schemas.relayerApiTokenPairsResponseSchema);
+        _.each(tokenPairs, (tokenPair: object) => {
+            typeConverters.convertStringsFieldsToBigNumbers(tokenPair, [
+                'tokenA.minAmount',
+                'tokenA.maxAmount',
+                'tokenB.minAmount',
+                'tokenB.maxAmount',
+            ]);
+        });
+        return tokenPairs;
+    }
+    /**
+     * Retrieve orders from the API
+     * @param   request     An OrdersRequest instance describing specific orders to retrieve
+     * @return  The resulting SignedOrders that match the request
+     */
+    public async getOrdersAsync(request?: OrdersRequest): Promise<SignedOrder[]> {
+        if (!_.isUndefined(request)) {
+            assert.doesConformToSchema('request', request, clientSchemas.relayerOrdersRequestSchema);
+        }
+        const requestOpts = {
+            params: request,
+        };
+        const orders = await this._requestAsync(`/orders`, HttpRequestType.Get, requestOpts);
+        assert.doesConformToSchema('orders', orders, schemas.signedOrdersSchema);
+        _.each(orders, (order: object) => typeConverters.convertOrderStringFieldsToBigNumber(order));
+        return orders;
+    }
+    /**
+     * Retrieve a specific order from the API
+     * @param   orderHash     An orderHash generated from the desired order
+     * @return  The SignedOrder that matches the supplied orderHash
+     */
+    public async getOrderAsync(orderHash: string): Promise<SignedOrder> {
+        assert.doesConformToSchema('orderHash', orderHash, schemas.orderHashSchema);
+        const order = await this._requestAsync(`/order/${orderHash}`, HttpRequestType.Get);
+        assert.doesConformToSchema('order', order, schemas.signedOrderSchema);
+        typeConverters.convertOrderStringFieldsToBigNumber(order);
+        return order;
+    }
+    /**
+     * Retrieve an orderbook from the API
+     * @param   request     An OrderbookRequest instance describing the specific orderbook to retrieve
+     * @return  The resulting OrderbookResponse that matches the request
+     */
+    public async getOrderbookAsync(request: OrderbookRequest): Promise<OrderbookResponse> {
+        assert.doesConformToSchema('request', request, clientSchemas.relayerOrderBookRequestSchema);
+        const requestOpts = {
+            params: request,
+        };
+        const orderBook = await this._requestAsync('/orderbook', HttpRequestType.Get, requestOpts);
+        assert.doesConformToSchema('orderBook', orderBook, schemas.relayerApiOrderBookResponseSchema);
+        typeConverters.convertOrderbookStringFieldsToBigNumber(orderBook);
+        return orderBook;
+    }
+    /**
+     * Retrieve fee information from the API
+     * @param   request     A FeesRequest instance describing the specific fees to retrieve
+     * @return  The resulting FeesResponse that matches the request
+     */
+    public async getFeesAsync(request: FeesRequest): Promise<FeesResponse> {
+        assert.doesConformToSchema('request', request, schemas.relayerApiFeesPayloadSchema);
+        typeConverters.convertBigNumberFieldsToStrings(request, [
+            'makerTokenAmount',
+            'takerTokenAmount',
+            'expirationUnixTimestampSec',
+            'salt',
+        ]);
+        const requestOpts = {
+            payload: request,
+        };
+        const fees = await this._requestAsync('/fees', HttpRequestType.Post, requestOpts);
+        assert.doesConformToSchema('fees', fees, schemas.relayerApiFeesResponseSchema);
+        typeConverters.convertStringsFieldsToBigNumbers(fees, ['makerFee', 'takerFee']);
+        return fees;
+    }
+    /**
+     * Submit a signed order to the API
+     * @param   signedOrder     A SignedOrder instance to submit
+     */
+    public async submitOrderAsync(signedOrder: SignedOrder): Promise<void> {
+        assert.doesConformToSchema('signedOrder', signedOrder, schemas.signedOrderSchema);
+        const requestOpts = {
+            payload: signedOrder,
+        };
+        await this._requestAsync('/order', HttpRequestType.Post, requestOpts);
+    }
+    private async _requestAsync(path: string, requestType: HttpRequestType,
+                                requestOptions?: HttpRequestOptions): Promise<any> {
+        const params = _.get(requestOptions, 'params');
+        const payload = _.get(requestOptions, 'payload');
+        let query = '';
+        if (!_.isUndefined(params) && !_.isEmpty(params)) {
+            const stringifiedParams = queryString.stringify(params);
+            query = `?${stringifiedParams}`;
+        }
+        const url = `${this.apiEndpointUrl}/v0${path}${query}`;
+        const headers = new Headers({
+            'content-type': 'application/json',
+        });
+
+        const response = await fetch(url, {
+            method: requestType,
+            body: JSON.stringify(payload),
+            headers,
+        });
+        if (!response.ok) {
+            throw Error(response.statusText);
+        }
+        const json = await response.json();
+        return json;
+    }
+}

packages/connect/src/index.ts

@@ -0,0 +1,11 @@
+export {HttpClient} from './http_client';
+export {
+    Client,
+    FeesRequest,
+    FeesResponse,
+    OrderbookRequest,
+    OrderbookResponse,
+    OrdersRequest,
+    TokenPairsItem,
+    TokenPairsRequest,
+} from './types';

packages/connect/src/schemas/relayer_fees_request_schema.ts

@@ -0,0 +1,8 @@
+export const relayerOrderBookRequestSchema = {
+    id: '/RelayerOrderBookRequest',
+    type: 'object',
+    properties: {
+        baseTokenAddress: {$ref: '/Address'},
+        quoteTokenAddress: {$ref: '/Address'},
+    },
+};

packages/connect/src/schemas/relayer_orderbook_request_schema.ts

@@ -0,0 +1,8 @@
+export const relayerOrderBookRequestSchema = {
+    id: '/RelayerOrderBookRequest',
+    type: 'object',
+    properties: {
+        baseTokenAddress: {$ref: '/Address'},
+        quoteTokenAddress: {$ref: '/Address'},
+    },
+};

packages/connect/src/schemas/relayer_orders_request_schema.ts

@@ -0,0 +1,16 @@
+export const relayerOrdersRequestSchema = {
+    id: '/RelayerOrdersRequest',
+    type: 'object',
+    properties: {
+        exchangeContractAddress: {$ref: '/Address'},
+        tokenAddress: {$ref: '/Address'},
+        makerTokenAddress: {$ref: '/Address'},
+        takerTokenAddress: {$ref: '/Address'},
+        tokenA: {$ref: '/Address'},
+        tokenB: {$ref: '/Address'},
+        maker: {$ref: '/Address'},
+        taker: {$ref: '/Address'},
+        trader: {$ref: '/Address'},
+        feeRecipient: {$ref: '/Address'},
+    },
+};

packages/connect/src/schemas/relayer_token_pairs_request_schema.ts

@@ -0,0 +1,8 @@
+export const relayerTokenPairsRequestSchema = {
+    id: '/RelayerTokenPairsRequest',
+    type: 'object',
+    properties: {
+        tokenA: {$ref: '/Address'},
+        tokenB: {$ref: '/Address'},
+    },
+};