2021-08-05 12:26:20 -04:00

291 lines
8.2 KiB
Python

import json
from typing import Dict, List, Optional
from pydantic import BaseModel
from mev_inspect.schemas.classified_traces import (
ClassifiedTrace,
Classification,
Protocol,
)
from mev_inspect.schemas.strategies import Arbitrage
class Transfer(BaseModel):
transaction_hash: str
trace_address: List[int]
from_address: str
to_address: str
amount: int
token_address: str
class Swap(BaseModel):
abi_name: str
transaction_hash: str
protocol: Optional[Protocol]
pool_address: str
from_address: str
to_address: str
token_in_address: str
token_in_amount: int
token_out_address: str
token_out_amount: int
def get_arbitrages(traces: List[ClassifiedTrace]) -> List[Arbitrage]:
all_arbitrages = []
traces_by_transaction = _group_traces_by_transaction(traces)
for transaction_traces in traces_by_transaction.values():
all_arbitrages += _get_arbitrages_for_transaction(
transaction_traces,
)
return all_arbitrages
def _group_traces_by_transaction(
traces: List[ClassifiedTrace],
) -> Dict[str, List[ClassifiedTrace]]:
grouped_traces: Dict[str, List[ClassifiedTrace]] = {}
for trace in traces:
hash = trace.transaction_hash
existing_traces = grouped_traces.get(hash, [])
grouped_traces[hash] = existing_traces + [trace]
return grouped_traces
def _get_arbitrages_for_transaction(
traces: List[ClassifiedTrace],
) -> List[Arbitrage]:
swaps = _get_swaps(traces)
print(json.dumps([swap.dict() for swap in swaps], indent=4))
return []
def _get_swaps(traces: List[ClassifiedTrace]) -> List[Swap]:
ordered_traces = list(sorted(traces, key=lambda t: t.trace_address))
swaps: List[Swap] = []
prior_traces: List[ClassifiedTrace] = []
for trace in ordered_traces:
if trace.classification == Classification.swap:
child_traces = _get_child_traces(trace.trace_address, traces)
swap = _build_swap(trace, prior_traces, child_traces)
if swap is not None:
swaps.append(swap)
prior_traces.append(trace)
return swaps
def _build_swap(
trace: ClassifiedTrace,
prior_traces: List[ClassifiedTrace],
child_traces: List[ClassifiedTrace],
) -> Optional[Swap]:
if trace.abi_name == "UniswapV2Pair":
return _parse_uniswap_v2_swap(trace, prior_traces, child_traces)
elif trace.abi_name == "UniswapV3Pool":
return _parse_uniswap_v3_swap(trace, child_traces)
return None
def _parse_uniswap_v3_swap(
trace: ClassifiedTrace,
child_traces: List[ClassifiedTrace],
) -> Optional[Swap]:
if trace.inputs is None:
return None
pool_address = trace.to_address
recipient_address = (
trace.inputs["recipient"]
if trace.inputs is not None and "recipient" in trace.inputs
else trace.from_address
)
child_transfers = _remove_inner_transfers(
[
_as_transfer(child_trace)
for child_trace in child_traces
if child_trace.classification == Classification.transfer
]
)
transfers_to_pool = [
child for child in child_transfers if child.to_address == pool_address
]
transfers_from_pool_to_recipient = [
child
for child in child_transfers
if (
child.from_address == pool_address and child.to_address == recipient_address
)
]
if len(transfers_to_pool) == 1 and len(transfers_from_pool_to_recipient) == 1:
transfer_in = transfers_to_pool[0]
transfer_out = transfers_from_pool_to_recipient[0]
return Swap(
abi_name="UniswapV3Pool",
transaction_hash=trace.transaction_hash,
pool_address=pool_address,
from_address=transfer_in.from_address,
to_address=transfer_out.to_address,
token_in_address=transfer_in.token_address,
token_in_amount=transfer_in.amount,
token_out_address=transfer_out.token_address,
token_out_amount=transfer_out.amount,
)
return None
def _parse_uniswap_v2_swap(
trace: ClassifiedTrace,
prior_traces: List[ClassifiedTrace],
child_traces: List[ClassifiedTrace],
) -> Optional[Swap]:
pool_address = trace.to_address
recipient_address = (
trace.inputs["to"]
if trace.inputs is not None and "to" in trace.inputs
else trace.from_address
)
prior_transfers = [
_as_transfer(prior_trace)
for prior_trace in prior_traces
if prior_trace.classification == Classification.transfer
]
child_transfers = [
_as_transfer(child)
for child in child_traces
if child.classification == Classification.transfer
]
transfers_to_pool = [
transfer for transfer in prior_transfers if transfer.to_address == pool_address
]
transfers_from_pool_to_recipient = [
transfer
for transfer in child_transfers
if (
transfer.to_address == recipient_address
and transfer.from_address == pool_address
)
]
# expecting a prior transfer to the pool
if len(transfers_to_pool) == 0:
return None
# expecting exactly one transfer inside the pool
if len(transfers_from_pool_to_recipient) != 1:
return None
transfer_in = transfers_to_pool[-1]
transfer_out = transfers_from_pool_to_recipient[0]
return Swap(
abi_name="UniswapV2Pair",
transaction_hash=trace.transaction_hash,
pool_address=pool_address,
from_address=transfer_in.from_address,
to_address=transfer_out.to_address,
token_in_address=transfer_in.token_address,
token_in_amount=transfer_in.amount,
token_out_address=transfer_out.token_address,
token_out_amount=transfer_out.amount,
)
def _get_child_traces(
parent_trace_address: List[int],
traces: List[ClassifiedTrace],
) -> List[ClassifiedTrace]:
ordered_traces = sorted(traces, key=lambda t: t.trace_address)
child_traces = []
for trace in ordered_traces:
if _is_child_trace_address(
parent_trace_address,
trace.trace_address,
):
child_traces.append(trace)
return child_traces
def _is_child_trace_address(
parent_trace_address: List[int],
maybe_child_trace_address: List[int],
) -> bool:
parent_trace_length = len(parent_trace_address)
return (len(maybe_child_trace_address) > parent_trace_length) and (
maybe_child_trace_address[:parent_trace_length] == parent_trace_address
)
def _remove_inner_transfers(transfers: List[Transfer]) -> List[Transfer]:
updated_transfers = []
transfer_trace_addresses: List[List[int]] = []
sorted_transfers = sorted(transfers, key=lambda t: t.trace_address)
for transfer in sorted_transfers:
if not any(
_is_subtrace(parent_address, transfer.trace_address)
for parent_address in transfer_trace_addresses
):
updated_transfers.append(transfer)
transfer_trace_addresses.append(transfer.trace_address)
return updated_transfers
def _is_subtrace(parent_trace_address, child_trace_address) -> bool:
return (
len(child_trace_address) > len(parent_trace_address)
and child_trace_address[: len(parent_trace_address)] == parent_trace_address
)
def _as_transfer(trace: ClassifiedTrace) -> Transfer:
# todo - this should be enforced at the data level
if trace.inputs is None:
raise ValueError("Invalid transfer")
if trace.protocol == Protocol.weth:
return Transfer(
transaction_hash=trace.transaction_hash,
trace_address=trace.trace_address,
amount=trace.inputs["wad"],
to_address=trace.inputs["dst"],
from_address=trace.from_address,
token_address=trace.to_address,
)
else:
return Transfer(
transaction_hash=trace.transaction_hash,
trace_address=trace.trace_address,
amount=trace.inputs["amount"],
to_address=trace.inputs["recipient"],
from_address=trace.inputs.get("sender", trace.from_address),
token_address=trace.to_address,
)