reconcileBalances.js

const axios = require('axios');

const apiURL = 'https://api.helius.xyz/v0/addresses/';
const resource = '/transactions';
const options = '?api-key=d63a869e-bb73-4792-ae33-a06f4c72f226&before=';
let lastTxn = '';
const SOL_PER_LAMPORT = 0.000000001;

const getAllTxns = async (address) => {
  const allTxns = [];

  while(true) {
    console.log("fetching transactions...")
    const { data } = await axios.get(apiURL + address + resource + options + lastTxn)
  
  if(!data.length) {
    console.log("got all transactions")
    break
  }
  
  lastTxn = data[data.length - 1].signature
  allTxns.push(...data);
}

  return allTxns
}

const getBalances = async (address) => {
  try {
    const { data } = await axios.get(apiURL + address + "/balances?api-key=d63a869e-bb73-4792-ae33-a06f4c72f226")

    return data
  } catch(e) {
    console.error("error: ", e)
  }
}

const reconcile = async (address) => {
  const allTxns = await getAllTxns(address);
  const balances =await  getBalances(address)
  let balanceSum = 0;

  for(let i = 0; i < allTxns.length; i++) {
    const txn = allTxns[i];
    const acct = txn.accountData.find(x => x.account == address)
    balanceSum += acct.nativeBalanceChange
  }

  console.log(`balance difference is ${Math.abs(balanceSum - balances.nativeBalance)*SOL_PER_LAMPORT} SOL`)
}

const address = '3imfKr7yLb1vLwfJQHxyZfc3XvhsjvaWojGzd6jrnWHv';
reconcile(address);