app.js

require('dotenv').config();
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var hbs = require('express-handlebars');

var index = require('./routes/index');
var users = require('./routes/users');
var login = require('./routes/login');
var register = require('./routes/register');
var booking = require('./routes/booking');


var MongoClient = require('mongodb').MongoClient;   // retrieve data base
var assert = require('assert');

var app = express();
app.get('env');

app.engine('hbs', hbs({extname: 'hbs', defaultLayout: 'layout', layoutsDir: __dirname + '/views/layouts/'}));
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'hbs');

// connect to DB
MongoClient.connect(process.env.MONGODB_URI, function (err, db) {
    assert.equal(null, err);
    console.log("Connected to database.");
    db.collection('notes').insertOne(
        {
            title: 'Hello MongoDB',
            text: 'Hopefully this works!'
        },
        function (err, res) {
            if (err) {
                db.close;
                return console.log(err);
            }
            // Success
            db.close();
        }
    )
    //db.close();
})

// uncomment after placing your favicon in /public
//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(express.static(path.join(__dirname, 'public')));

app.use('/', index);
app.use('/users', users);
app.use('/login', login);
app.use('/register', register);
app.use('/booking', booking);

// 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 handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

module.exports = app;