problem

const express = require('express');
const app = express();
const http = require('http');
const path = require('path');
const bodyParser = require('body-parser');
const cookieParser = require('cookie-parser');
const validator = require('express-validator');
const session = require('express-session');
const MongoStore = require('connect-mongo');
const mongoose = require('mongoose');
const flash = require('connect-flash');
const passport = require('passport');


module.exports = class Application {
    constructor() {
        this.setupExpress();
        this.setMongoConnection();
        this.setConfig();
    }

    setupExpress() {
        const server = http.createServer(app);
        server.listen(3000, () => console.log('Hello from 3000 bitch!'));
    }

    setMongoConnection() {
        mongoose.Promise = global.Promise;
        mongoose.connect('mongodb://localhost/nodejscms');
    }

    setConfig() {
        app.use(express.static('public'));
        app.set('view engine', 'ejs');
        app.set('views', path.resolve('./resource/views'));

        app.use(bodyParser.json());
        app.use(bodyParser.urlencoded({ extended : true}));

        app.use(session({
            secret : 'mysecretkey',
            resave : true, 
            saveUninitialized : true, 
            store : MongoStore.create({ mongooseConnection : mongoose.connection })
        }))

        app.use(cookieParser('mysecretkey'));
        app.use(flash());


        app.get('/', (req, res) => {
            res.json('Hello BITCH!');
        })
    }
}