what to use socket io ? code example

Example 1: how to run socket.io server

const express = require("express");
const http = require("http");
const socketIo = require("socket.io");
const port = process.env.PORT || 8001;
const index = require("./routes/index");
const app = express();
app.use(index);
const server = http.createServer(app);
const io = socketIo(server); // < Interesting!
const getApiAndEmit = "TODO";

Example 2: socket io query

// Client side
const socket = io({
  query: { token: 'cde' }
});

// Server side
io.on('connection', (socket) => {
  let token = socket.handshake.query.token;
  
  // Do something...
});