text: var app  = require('express')();
  var http = require('http').createServer(app);
  var io   = require('socket.io')(http);
  
  const PORT = process.env.HTTPD_PORT || 3000;
  
  app.get('/about', (req, res) => {
    res.send('<h1>Hello socket.io world!!!</h1>');
  });
  
  app.get('/', (req, res) => {
    res.sendFile(__dirname + '/index.html');
  });
  
  io.on('connection', socket => {
    socket.on('chat message', msg => {
      console.log(`chat message: ${msg}`);
      io.emit('chat message', msg);
    });
  });
  
  http.listen(PORT, () => {
    console.log(`listening on *:${PORT} at ${Date()}`);
  });
  