Running the server

Before we start using Socket.IO, let's first write a simple Node.js server code, which responds with the chat's page. We can see the server code as follows:

var http = require('http'),
  fs = require('fs'),
  port = 3000,
  html = fs.readFileSync(__dirname + '/html/page.html', {encoding: 'utf8'}),
  css = fs.readFileSync(__dirname + '/css/styles.css', {encoding: 'utf8'});

var app = http.createServer(function (req, res) {
  if(req.url === '/styles.css') {
    res.writeHead(200, {'Content-Type': 'text/css'});
    res.end(css);
  } else {
    res.writeHead(200, {'Content-Type': 'text/html'});
    res.end(html);
  }
}).listen(port, '127.0.0.1');

The preceding code should be placed in /index.js. The script starts with the definition of several global variables. The http module is used to create the server, and the fs module is used to read the CSS...