app.js

if (process.env.NODE_ENV != 'production') {
  //if there is an environment variable 'NODE_ENV' set to 'production' then we don't
  //load the environment variables that are contained in the file '.env'
  require('dotenv').load();
}
var express = require('express'); //a server-side JS framework
var mongoose = require('mongoose'); //to connect to MongoDD
//to extract the body portion of an incoming request and exposes it on
//req.body as something easier to deal with
var bodyParser = require('body-parser');
var path = require('path'); //to deal with file paths
var favicon = require('serve-favicon'); //to manage the favicon of the website
var logger = require('morgan'); //to show a log with what is happening in the server
var cookieParser = require('cookie-parser'); //to work with cookies
var passport = require('passport'); //to work with the authentication system

require('./app_api/models/db');
var routesApi = require('./app_api/routes/routes');
var routesServer = require('./app_server/routes/routes');

var app = express();

//view engine setup. We will work with JADE templates
app.set('views', path.join(__dirname, 'app_server', 'views'));
app.set('view engine', 'jade');

//initial setups
app.use(favicon(path.join(__dirname, 'app_client', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());

//folders in which there will be static files in the project
app.use(express.static(path.join(__dirname, 'dist')));
app.use(express.static(path.join(__dirname, 'app_client')));
app.use(express.static(path.join(__dirname, 'presentations')));
app.use(express.static(path.join(__dirname, 'bower_components')));

app.use('/api', routesApi); //routes for the REST API (start always with /api)
app.use('/', routesServer); //routes for the different web pages of the site

//catch 404 and forward to error handler
app.use(function(req, res, next) {
  var err = new Error('Oh! I cannot find that page');
  err.status = 404;
  err.imageSrc = 'error-404.png';
  err.imageAlt = 'Error 404';
  next(err);
});

//generic error handler
app.use(function(err, req, res, next) {
  res.render('error', {
    error: {
      imageSrc : err.imageSrc,
      imageAlt : err.imageAlt,
      status: err.status,
      stack: (process.env.NODE_ENV == 'development') ? err.stack : ''
    },
    lang: {
      message: err.message,
      title: 'MultiChat: Error'
    }
  })
});

var httpsServer = require('./app_server/servers/http.js')(app); //HTTP server
require('./app_server/servers/websockets.js')(httpsServer); //Websockets server