old_contents: var app = require('express')()
  var http = require('http').Server(app)
  var io = require('socket.io')(http)
  
  var shortURLPromise
    , short = require('short');
   
  // connect to mongodb 
  short.connect('mongodb://localhost/short');
  
  app.get('/', function (req, res) {
    res.sendFile(__dirname + '/index.html')
  })
  
  io.on('connection', function (socket) {
    console.log("Someone connected")
    socket.on('url', function (msg) {
      var shortURLPromise = short.generate({ URL : msg })
      
      shortURLPromise.then(function(mongodbDoc) {
        console.log("Long: " + mongodbDoc.URL)
        console.log("Short: " + mongodbDoc.hash)
        io.emit('short', msg)
        short.retrieve(mongodbDoc.hash).then(function(result) {
          io.emit('long', result.hash)
        })
      })
    })
  })
  
  http.listen(3000, function () {
    console.log('listening on *:3000')
  })
  
new_contents: var app = require('express')()
  var http = require('http').Server(app)
  var io = require('socket.io')(http)
  
  var shortURLPromise
    , short = require('short');
   
  // connect to mongodb 
  short.connect('mongodb://localhost/short');
  
  app.get('/', function (req, res) {
    res.sendFile(__dirname + '/index.html')
  })
  
  io.on('connection', function (socket) {
    console.log("Someone connected")
    socket.on('url', function (msg) {
      var shortURLPromise = short.generate({ URL : msg })
      
      shortURLPromise.then(function(mongodbDoc) {
        console.log("Long: " + mongodbDoc.URL)
        console.log("Short: " + mongodbDoc.hash)
        io.emit('short', msg)
        short.retrieve(mongodbDoc.hash).then(function(result) {
          io.emit('long', result.hash)
        })
      })
    })
  })
  
  http.listen(3000, function () {
    console.log('listening on *:3004')
  })
  
subject: change port