Batch check balance of addresses with my node?

Question

I have a txt file with around 1300 ethereum addreses (1 each line) that I have saved during the years. Now I am running a node since some time and would like to utilize it to automatically check the balance of each address quickly. Of course I can manually import or manually check it but it got to be a way to automate it :D

How can I utilize my ethereum node to use the check balance function, one by one, from wallet.txt, and I guess inform somehow about if the address balance is above 0.

Manually via the geth javascript console I could use

web3.fromWei(web3.eth.getBalance('0xbd3Afb0bB76683eCb4225F9DBc91f998713C3b01'));

Result:

0.483296293327556759

OR via terminal

curl -X POST localhost:8545 \
-H "Content-Type: application/json" \
--data \
'
{
  "jsonrpc": "2.0",
  "method": "eth_getBalance",
  "params": ["0xbd3Afb0bB76683eCb4225F9DBc91f998713C3b01", "latest"],
  "id": 1
}
' 

Result:

{"jsonrpc":"2.0","result":"0x728d934e8054bc7","id":1}

(a hex number which is ok i can convert it manually - if 0 then its 0x0)

But! Is there any way to automate this :D?

Thanks in advance!!

Answer 1

You can just connect to your geth node and run the same js code in a loop:

const fs = require("fs");
const ethers = require("ethers");

let provider = new ethers.providers.JsonRpcProvider("http://localhost:8545");

let addresses = fs.readFileSync("wallet.txt", "utf-8").split("\n");

addresses = addresses.map(address => address.trim());

async function fetchBalances() {
  for (let address of addresses) {
    if (address.length === 0) continue;
    try {
      let balance = await provider.getBalance(address);
      let balanceInEther = ethers.utils.formatEther(balance);
      if (balanceInEther === "0.0") continue;
      console.log(`Balance of ${address}: ${balanceInEther} Ether`);
    } catch (error) {
      console.log(`Error fetching balance for address ${address}: ${error.message}`);
    }
  }
}

fetchBalances();