Based on makerdao's multicall contractand brownie implementation with batching and asynchronous support. Works directly with web3py contract functions and parameters
pip install web3mcBasic usage
(this is default value if empty - set by web3py)
export WEB3_HTTP_PROVIDER_URI=http://localhost:8545from web3.auto import w3
from web3mc.auto import multicall
abi = [{"constant": True, "inputs": [], "name": "name", "outputs": [{"name": "", "type": "string"}], "payable": False,
"stateMutability": "view", "type": "function", },
{"constant": True, "inputs": [], "name": "symbol", "outputs": [{"name": "", "type": "string"}], "payable": False,
"stateMutability": "view", "type": "function", },
{"constant": True, "inputs": [{"name": "", "type": "address"}], "name": "balanceOf",
"outputs": [{"name": "", "type": "uint256"}], "payable": False, "stateMutability": "view", "type": "function"}]
weth_erc20 = w3.eth.contract("0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2", abi=abi)
calls = [weth_erc20.functions.name(), weth_erc20.functions.symbol(), weth_erc20.functions.balanceOf("vitalik.eth")]
result = multicall.aggregate(calls)
print(result) # ['Wrapped Ether', 'WETH', 26992040046283229929]Call multiple contracts with same abi (implementation)
...
weth_erc20 = w3.eth.contract("0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2", abi=abi)
calls = [weth_erc20.functions.name(),weth_erc20.functions.symbol(),weth_erc20.functions.balanceOf("vitalik.eth")] * 2
# WBTC, USDC
addresses = ["0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2"] * 3 + ["0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599"] * 3
result = multicall.aggregate(calls, use_try=True, addresses=addresses) # tryAggregate()
print(result) # ['Wrapped BTC', 'WBTC', 0, 'USD Coin', 'USDC', 396267093705]-
WEB3_HTTP_PROVIDER_URI- can be overwritten directly (from web3py)
from web3mc import Multicall
multicall = Multicall(
provider_url="<your custom provider url>", # Overrides env parameter
batch=100, # can lead to overflow
max_retries=3, # retries without use_try (aggregate function in contract)
gas_limit=50_000_000, # gas limit for calls
_semaphore=1000, # max concurrent coroutines, change carefully!
)Install dependencies, make sure you set WEB3_HTTP_PROVIDER_URI environment variable
pytest tests
