Migrate Python libraries to v3 (#2284)

* .gitignore migrations/0x_ganache_snapshot

* .gitignore new-ish Python contract wrappers

These should have been added back when we started generating these
wrappers.

* rm superfluous contract artifact in Python package

All of the contract artifacts were removed from the Python package
recently, because now they're copied from the monorepo/packages area as
an automated build step.  Somehow this one artifact slipped through the
cracks.

* Eliminate circular dependency

This was preventing the Exchange wrapper from ever importing its
validator!

* Improve output of monorepo-level parallel script

- Capture stderr (and have it included in stdout) so that it doesn't
leak onto the console for commands that didn't actually fail.

- Include all error output in the Exception object (eliminate print
statement).

* Silence new versions of linters

Newer versions care about this stuff.  Old versions didn't, and we don't
either.

* Support Rich Reverts via Web3.py middleware

* Fix bug in generated wrappers' bytes handling

`bytes.fromhex(bytes.decode('utf-8')` is just plain wrong.  It would
work for some cases, but is not working when trying to fill orders with
the latest Exchange contract.

* Migrate to Exchange v3

* Fix typo in DevUtils documentation

* Include new contracts in docs

* Re-enable Python checks in CI

* Accept strings for bytes

* Fix CircleCI build artifacts for gen'd python

I swear the previous way was working before, but it wasn't working now,
so this fixes it.

* Accept a provider OR a Web3 object

In various places.  This allows the caller to install middleware (which
in web3.py is installed on a Web3 object, not on a provider) before
executing any RPC calls, which is important for the case where one wants
to produce signatures locally before submitting to a remote node.

* wrapper base: don't assume there are accounts

* Eliminate some inline linter directives

* make CHANGELOGs be REVERSE chronological

* Update CHANGELOG entries and bump version numbers

* @0x/contract-addresses: Put addr's in JSON, not TS

This allows easier consumption by other languages.  (Specifically, it
eliminates the overhead of keeping the Python addresses package in sync
with the TypeScript one.)

* sra_client.py: incl. docker in `./setup.py clean`

* sra_client.py: Migrate to protocol v3

Removed script that existed only to exclude runs of sra_client builds
(parallel_without_sra_client).  Now `parallel` is used by CI,
re-including sra_client in CI checks.

* abi-gen/templates/Py: clarify if/else logic

In response to
https://github.com/0xProject/0x-monorepo/pull/2284#discussion_r342200906

* sra_client.py: Update CHANGELOG and bump version

* contract_addresses/setup.py: rm unnecessary rm

* json_schemas.py: corrections to dev dependencies

* In tests against deployment, also run doctests

* contract_wrappers example: rm xtra Order attribute

Thanks to @steveklebanoff for catching this.
https://github.com/0xProject/0x-monorepo/pull/2284#pullrequestreview-312065368

python-packages/contract_wrappers/test/test_exchange_wrapper.py

@@ -5,20 +5,24 @@ import random
 import pytest
 from eth_utils import remove_0x_prefix
 
-from zero_ex.contract_addresses import NETWORK_TO_ADDRESSES, NetworkId
+from zero_ex.contract_addresses import network_to_addresses, NetworkId
 from zero_ex.contract_wrappers import TxParams
 from zero_ex.contract_wrappers.exchange import Exchange
 from zero_ex.contract_wrappers.exchange.types import Order
 from zero_ex.json_schemas import assert_valid
-from zero_ex.order_utils import generate_order_hash_hex, sign_hash_to_bytes
+from zero_ex.order_utils import (
+    asset_data_utils,
+    generate_order_hash_hex,
+    sign_hash,
+)
 
 
 @pytest.fixture(scope="module")
 def exchange_wrapper(ganache_provider):
     """Get an Exchange wrapper instance."""
     return Exchange(
-        provider=ganache_provider,
-        contract_address=NETWORK_TO_ADDRESSES[NetworkId.GANACHE].exchange,
+        web3_or_provider=ganache_provider,
+        contract_address=network_to_addresses(NetworkId.GANACHE).exchange,
     )
 
 
@@ -43,6 +47,8 @@ def create_test_order(
         salt=random.randint(1, 1000000000),
         makerAssetData=maker_asset_data,
         takerAssetData=taker_asset_data,
+        makerFeeAssetData=asset_data_utils.encode_erc20("0x" + "00" * 20),
+        takerFeeAssetData=asset_data_utils.encode_erc20("0x" + "00" * 20),
     )
     return order
 
@@ -67,16 +73,29 @@ def test_exchange_wrapper__fill_order(
     exchange_wrapper,  # pylint: disable=redefined-outer-name
     ganache_provider,
     weth_asset_data,
+    zrx_asset_data,
 ):
     """Test filling an order."""
     taker = accounts[0]
     maker = accounts[1]
     exchange_address = exchange_wrapper.contract_address
-    order = create_test_order(maker, 1, weth_asset_data, 1, weth_asset_data)
+    order = create_test_order(maker, 1, weth_asset_data, 1, zrx_asset_data)
     order_hash = generate_order_hash_hex(
-        order=order, exchange_address=exchange_address
+        order=order, exchange_address=exchange_address, chain_id=1337
     )
-    order_signature = sign_hash_to_bytes(ganache_provider, maker, order_hash)
+    order_signature = sign_hash(ganache_provider, maker, order_hash)
+
+    fill_results = exchange_wrapper.fill_order.call(
+        order=order,
+        taker_asset_fill_amount=order["takerAssetAmount"],
+        signature=order_signature,
+        tx_params=TxParams(from_=taker),
+    )
+    assert fill_results[0] == 1
+    assert fill_results[1] == 1
+    assert fill_results[2] == 0
+    assert fill_results[3] == 0
+    assert fill_results[4] == 0
 
     tx_hash = exchange_wrapper.fill_order.send_transaction(
         order=order,
@@ -107,11 +126,13 @@ def test_exchange_wrapper__batch_fill_orders(
     orders.append(order_1)
     orders.append(order_2)
     order_hashes = [
-        generate_order_hash_hex(order=order, exchange_address=exchange_address)
+        generate_order_hash_hex(
+            order=order, exchange_address=exchange_address, chain_id=1337
+        )
         for order in orders
     ]
     order_signatures = [
-        sign_hash_to_bytes(ganache_provider, maker, order_hash)
+        sign_hash(ganache_provider, maker, order_hash)
         for order_hash in order_hashes
     ]
     taker_amounts = [order["takerAssetAmount"] for order in orders]
@@ -128,3 +149,20 @@ def test_exchange_wrapper__batch_fill_orders(
         assert_fill_log(
             fill_events[index].args, maker, taker, order, order_hashes[index]
         )
+
+
+def test_two_instantiations_with_web3_objects(web3_instance):
+    """Test that instantiating two Exchange objects doesn't raise.
+
+    When instantiating an Exchange object with a web3 client (rather than a
+    provider) there was a bug encountered where web3.py was giving an error
+    when trying to install the rich-revert-handling middleware on the web3
+    client, an error saying "can't install this same middleware instance
+    again."  Test that that bug isn't occurring.
+    """
+    exchange = Exchange(  # pylint: disable=unused-variable
+        web3_instance, network_to_addresses(NetworkId.GANACHE).exchange
+    )
+    exchange2 = Exchange(  # pylint: disable=unused-variable
+        web3_instance, network_to_addresses(NetworkId.GANACHE).exchange
+    )