ethers-multicall项目解读

今天给网友推荐了合约multicall调用方式，然后另外一个网友抛出了cavanmflynn/ethers-multicall: Make multiple Ethereum network requests in a single HTTP query. ethcall for ethers v5. (github.com) 并且叫开始那个网友看readme,说这个是一个不一样的东西，所以我稍微做一下代码解读。

ethers-multicall的文档

const ethcallProvider = new Provider(provider);

  await ethcallProvider.init(); // Only required when `chainId` is not provided in the `Provider` constructor

  const daiContract = new Contract(daiAddress, erc20Abi);

  const uniswapDaiPool = '0x2a1530c4c41db0b0b2bb646cb5eb1a67b7158667';

  const ethBalanceCall = ethcallProvider.getEthBalance(uniswapDaiPool);
  const daiBalanceCall = daiContract.balanceOf(uniswapDaiPool);

  const [ethBalance, daiBalance] = await ethcallProvider.all([ethBalanceCall, daiBalanceCall]);

  console.log('ETH Balance:', ethBalance.toString());
  console.log('DAI Balance:', daiBalance.toString());

主要通过all函数来实现 multicall。 可是all函数是怎么调用的呢，代码在 provider.ts

public async all<T extends any[] = any[]>(calls: ContractCall[]) {
    if (!this._provider) {
      throw new Error('Provider should be initialized before use.');
    }
    return all<T>(calls, this._multicallAddress, this._provider);
  }

const multicallAddresses = {
  1: '0xeefba1e63905ef1d7acba5a8513c70307c1ce441',
  3: '0xF24b01476a55d635118ca848fbc7Dab69d403be3',
  4: '0x42ad527de7d4e9d9d011ac45b31d8551f8fe9821',
  5: '0x77dca2c955b15e9de4dbbcf1246b4b85b651e50e',
  42: '0x2cc8688c5f75e365aaeeb4ea8d6a480405a48d2a',
  56: '0x1Ee38d535d541c55C9dae27B12edf090C608E6Fb',
  66: '0x94fEadE0D3D832E4A05d459eBeA9350c6cDd3bCa',
  97: '0x3A09ad1B8535F25b48e6Fa0CFd07dB6B017b31B2',
  100: '0xb5b692a88bdfc81ca69dcb1d924f59f0413a602a',
  128: '0x2C55D51804CF5b436BA5AF37bD7b8E5DB70EBf29',
  137: '0x11ce4B23bD875D7F5C6a31084f55fDe1e9A87507',
  250: '0x0118EF741097D0d3cc88e46233Da1e407d9ac139',
  1337: '0x77dca2c955b15e9de4dbbcf1246b4b85b651e50e',
  42161: '0x813715eF627B01f4931d8C6F8D2459F26E19137E',
  43114: '0x7f3aC7C283d7E6662D886F494f7bc6F1993cDacf',
  80001: '0x08411ADd0b5AA8ee47563b146743C13b3556c9Cc',
};

做个简单假设，multicallAddresses 中的1，是链的id ethscan 搜索 0xeefba1e63905ef1d7acba5a8513c70307c1ce441

Multicall | 0xeefba1e63905ef1d7acba5a8513c70307c1ce441 (etherscan.io)

我想你会看到的。 作者在不同的链上都部署了multicall合约。 不信你可以多搜索几个试试！ multicall合约代码，我就不给大家解读了，前面有文章提到过。一个蜜罐合约的解析（二）调用隐藏 | 登链社区 | 深入浅出区块链技术 (learnblockchain.cn) 欢迎大家讨论。