Angular Service Wrapped for Socket.io

services.js

services.factory('socket', function ($rootScope) {
    'use strict';
    var socket;
    
    var connect = function(){
          if(!socket){
            socket = io.connect('http://localhost:3000/');
          }
    };
    
    connect();
    
    return {
        on: function (eventName, callback) {
          socket.on(eventName, function () {  
            var args = arguments;
            $rootScope.$apply(function () {
              callback.apply(socket, args);
            });
          });
        },
        emit: function (eventName, data, callback) {
            socket.emit(eventName, data, function () {
                var args = arguments;
                    $rootScope.$apply(function () {
                        if (callback) {
                            callback.apply(socket, args);
                    }
                });
          });
        },
        disconnect: function(){
          socket.disconnect();
        }
    };
})