WebSocket NodeJS Server written in YouTube video https://www.youtube.com/watch?v=_Z9Axfh6AEU

server.js

const app = require('express')();
const appWs = require('express-ws')(app);

app.ws('/echo', ws => {
    ws.on('message', msg => {
        console.log('Received: ', msg);
        ws.send(msg);
    });
});

app.listen(1337, () => console.log('Server has been started'));