app.js

var express = require('express');
var compress = require('compression');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var session = require('express-session');    
var MongoStore = require('connect-mongo')(session);  
var bodyParser = require('body-parser');
var dotenv = require('dotenv');
var mongoose = require('mongoose');

var routes = require('./routes/index');
var users = require('./routes/users');
var dict = require('./routes/dict');
var api = require('./routes/api');

/**
 * Load environment variables from .env file, where API keys and passwords are configured.
 *
 * Default path: .env (You can remove the path argument entirely, after renaming `.env.example` to `.env`)
 */
dotenv.load({ path: '.env.example' });


var app = express();

/**
 * Connect to MongoDB.
 */
mongoose.connect(process.env.MONGODB || process.env.MONGOLAB_URI);
mongoose.connection.on('error', function() {
  console.log('MongoDB Connection Error. Please make sure that MongoDB is running.');
  process.exit(1);
});

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'hbs');

// uncomment after placing your favicon in /public
app.use(compress());
app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(session({                                                           
  resave: true,
  saveUninitialized: true,
  secret: process.env.SESSION_SECRET,
  store: new MongoStore({
       mongooseConnection: mongoose.connection
  })
}));
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', routes);
app.use('/users', users);
app.use('/dict', dict);
app.use('/api', api);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  var err = new Error('Not Found');
  err.status = 404;
  next(err);
});

// error handlers

// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
  app.use(function(err, req, res, next) {
    res.status(err.status || 500);
    res.render('error', {
      message: err.message,
      error: err
    });
  });
}

// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
  res.status(err.status || 500);
  res.render('error', {
    message: err.message,
    error: {}
  });
});


module.exports = app;