getAllTxns.js

const axios = require('axios');

const apiURL = 'https://api.helius.xyz/v0/addresses/';
const address = '8cRrU1NzNpjL3k2BwjW3VixAcX6VFc29KHr4KZg8cs2Y';
const resource = '/transactions';
const options = '?api-key=d63a869e-bb73-4792-ae33-a06f4c72f226&before=';
let lastTxn = '';
const allTxns = [];

const getAllTxns = async () => {
  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);
}

  console.log("Total transactions: ", allTxns.length)
}

getAllTxns()