Is there any working example that uses nodeJS + peerJS?

I spent my whole day trying to set up my app using peer but couldn't succeed so far.

Here's what my server js file looks like:

const path = require('path');
const express = require('express');
const { ExpressPeerServer } = require('peer');
const app = express();
const PORT = process.env.PORT || 3000;

// set your static server
app.use(express.static(path.resolve(`${__dirname}/public`)));

// views
app.get('/', (req, res) => {
    res.sendFile(path.join(__dirname, 'views/index.html'));
});

// start listening
const server = app.listen(PORT);
console.log('Server is running localhost on port: ' + PORT);

// peerjs
const peerServer = ExpressPeerServer(server, {
    debug: true,
});

app.use('/peerjs', peerServer);

// listeners
peerServer.on('connection', (client) => {
    console.log("Server: Peer connected with ID:", client.id);
});

peerServer.on('disconnect', (client) => {
    console.log("Server: Peer disconnected with ID:", client.id);
});

When I run the app, it says Server: Peer connected with ID: ff1b23c0-9b67-49e3-8461-35405397d3b2 but then a minute later it says Server: Peer disconnected with ID: ff1b23c0-9b67-49e3-8461-35405397d3b2.

Also, I failed to make the server connect to the client. The peer.on('connection', function(conn) {} function never gets called. I may be missing something.

So I'm trying to find an example code that works but so far I haven't found any example(using nodeJS, express, peerJS) that works.

Can anyone please introduce me to any working example of a node app that uses peer?

All I want is just to check the server-client connection as a first step. (without the connection being disconnected automatically)

Solution

Here is a small working example, I have tried this myself.

Your backend Express Server:

const express = require('express');
const { ExpressPeerServer } = require('peer');
const cors = require('cors');

const app = express();

app.use(cors());

app.get('/', (req, res, next) => res.send('Hello world!'));

const server = app.listen(9000);

const peerServer = ExpressPeerServer(server, {
  debug: true
});

app.use('/peerjs', peerServer);

peerServer.on('connection', (client) => { console.log('client connected');});
peerServer.on('disconnect', (client) => { console.log('client disconnected');});

And your frontend code to connect with above peer server:

<html>
<head>
    <script src="https://cdn.jsdelivr.net/npm/peerjs@0.3.20/dist/peer.min.js"></script>
</head>
<body>
    <script>
        const peer = new Peer('someid', {
          host: 'localhost',
          port: 9000,
          path: '/peerjs'
        });
    </script>
</body>
</html>