Use `@pooltogether/etherplex` to get multiple token contract balances for an address AT A PARTICULAR BLOCK HEIGHT

Question

I am trying to use @pooltogether/etherplex to get the token balances across several token contracts for an address at a particular block height. I have successfully used the code from https://github.com/chainstack/ethereum-token-balances, particularly the file etherplex.js contains the code I'm using. I made a few slight modifications so it pulls from a pre-curated list of tokens instead of getting a token list from Coingecko. Here it is:

const { ethers } = require('ethers');
const fs = require('fs')
const { batch, contract } = require('@pooltogether/etherplex');

const { abi, username, password, rpcEndpoint, walletAddress, blockNumber } = require('./constant.js');
const { convertToNumber, getTokens } = require('./utils');

const provider = new ethers.providers.JsonRpcProvider({
  url: rpcEndpoint,
  user: username,
  password: password,
});

const generateContractFunctionList = tokens =>
  tokens.map(({ address: tokenAddress, symbol }) =>
    contract(symbol, abi, tokenAddress).balanceOf(walletAddress),
  );

const main = async () => {
  //const { tokens } = await getTokens();
  const tokens = JSON.parse(fs.readFileSync('./tokenArrayFormatted1.json'));
  const start = new Date().getTime();
  const args = generateContractFunctionList(tokens);
  const tokenBalances = await batch.apply(null, [provider, ...args])
    .then(balances => {
      const output = {};

      Object.entries(balances).map(([symbol, { balanceOf }], index) => {
        const balance = convertToNumber(balanceOf[0]._hex, tokens[index].decimals);

        output[tokens[index].name] = `${balance} ${symbol}`;
      });

      return output;
    });

  console.log(tokenBalances);
};

main();

The result of the above code is this:

{
  'Deeper Network': '2536809291877779012962 DPR',
  'Butterfly Protocol Governance Token': '500000000000000000000 BFLY',
  PolkaFoundry: '181155501024337317854 PKF',
  'NOIA Token': '333051750809558494435 NOIA',
  'Marlin POND': '1440041248418898225293 POND',
  'Parsiq Token': '97647679865505205154 PRQ',
  'Ampleforth Governance': '2000000000000000000 FORTH',
  'Sora Token': '190218199929215762 XOR',
  Umbrella: '94213894452399722272 UMB',
  'Kylin Network': '122026806656382486733 KYL',
  'YfDAI.finance': '27412986448951619 Yf-DAI',
  'Tixl Token': '50000000000000000000 TXL',
  'BarnBridge Governance Token': '0 BARN',
  'USD Coin': '0 USDC',
  Uniswap: '0 UNI',
  DuckDaoDime: '0 DDIM',
  'DLP Duck Token': '0 DLP',
  'Darwinia Network Native Token': '0 RING',
  'aleph.im v2': '0 ALEPH',
  'Injective Token': '0 INJ',
  erowan: '0 EROWAN',
  'Matic Token': '0 MATIC',
  'APY Governance Token': '0 APY'
}

The problem is I need to find the token balances at an older block height. My API from Chainstack is connected to an archive geth node. So how do I pass a block number into the above code to get the token balances at a particular block height?

Answer 1

we've recently released a newer and expanded version of the code with the instructions, check it out https://chainstack.com/ultimate-guide-erc20-token-balance/

It specifically has the parameter to query for token balances at a block number.