Can I subscribe event fire from smart contract's events with NodeJS?

Question

I just wrote smart contract function with fire event like this.

And create my node.js application with following code.

const express = require('express')
const Web3 = require('web3');
const app = express()
const PORT = process.env.PORT || 8080
const privateKey = "-- secret"
const { CONTRACT_ABI, CONTRACT_ADDRESS } = require('./config');
const web3 = new Web3('https://data-seed-prebsc-1-s1.binance.org:8545');
const contract = new web3.eth.Contract(CONTRACT_ABI, CONTRACT_ADDRESS);

app.get('/send_transaction', async (req, res) => {
    const reciept = await send(web3, privateKey, contract)
    res.send(reciept);
});

contract.events.EndedRound({
    fromBlock: 0
}, function(error, event) { console.log(event); })
.on('data', function(event) {
    console.log(event) // no event coming here.
})

async function send(web3, privateKey, contract) {
    const account = web3.eth.accounts.privateKeyToAccount(privateKey).address;
    const transaction = contract.methods.endRound(1651799819, [1], Web3.utils.toWei("100"));
    const options = {
        to: transaction._parent._address,
        data: transaction.encodeABI(),
        gas: await transaction.estimateGas({ from: account })
    };
    const signed = await web3.eth.accounts.signTransaction(options, privateKey);
    const receipt = await web3.eth.sendSignedTransaction(signed.rawTransaction);
    return receipt;
}

app.listen(PORT, () => {
    console.log(`Server is running on port : ${PORT}`)
})
module.exports = app

But after I call function in smart contract which fire event EndedRound, My nodejs app not receive any event at all.

Is it possible to do that?

Answer 1

The event in the smart contract is 'EndRound' and the one in your express server is 'EndedRound'.