You know, the electron app will be running at end user.
So you should create Socket server at somewhere sth like Cloud server and your electron app should contain one socket.io client instance.

At Socket server

const app = require('express')();



const server = require('http').createServer(app);

const io = require('socket.io')(server);

io.on('connection', () => { /* … */ });

server.listen(3000);

And at frontend (your case Electron app side)

<script src="/socket.io/socket.io.js"></script>

<script>

  var socket = io('http://localhost');

  socket.on('connect', function(){});

  socket.on('event', function(data){});

  socket.on('disconnect', function(){});

</script> 

or

// with ES6 import

import io from 'socket.io-client';

 

const socket = io('http://localhost');

So that users can communicate inside your Electron app.