How to make guestbook with Express.js (part 1)

app.js

const express = require('express');
const morgan = require('morgan');
const bodyParser = require('body-parser');
// Define port for the server
const PORT = 3000;
const app = express();

// Require routes
const routes = require('./routes/routes');

// Set Application views directory
app.set('view', __dirname + 'views');
// Set Application view engine
app.set('view engine', 'ejs');

// Use body-parser to parse incoming requests and get body of it
app.use(bodyParser.urlencoded({ extended: false }));
// Log every activity on the server
app.use(morgan('dev'));

// Use required routes
app.use('/', routes);

// Start server and listen to port 3000
app.listen(PORT, () => {
  console.log(`Application is running on ${PORT}`);
});