Awesome

Multicall

A multicall contract enables a single eth_call to be used to aggregate multiple constant contract method calls to a variety of addresses.

The ethers Multicall contract is located at multicall.eth and is verified on Etherscan.

JavaScript API

const multicaller = Multicaller(provider);

// The maximum amount of gas to allow each sub-call to consume
multicaller.gasLimtPerCall = 50000;

// The maximum result length to allow each call to return
multicaller.resultLimitPerCall = 1024;

multicaller.queue(address, fragment [ , values ]) => Promise<any>
multicaller.queueResult(address, fragment [ , values ]) => Promise<Result>
multicall.flush() => Promise<number>

Contract API

const ABI = [
  "function execute(uint gasLimit, uint maxResultSize, address[] addrs, bytes[] datas) view returns (uint blockNumber, uint[] statuses, bytes[] results)"
];

const contract = new Contract("multicall.eth", ABI, provider);

There is a single method, execute which will throttle the amount of gas per external call and limit the resulting output from each call to prevent malicious contracts from breaking the aggregate call.

Each result includes a status (0 for failure, 1 for successs) along with any result. A status of 0 may still return data, which will be the result of the revert.

License

MIT License.