Basic Express server serving a simplest app with server object exported for tests

app.js

'use strict';

const app = require('express')();

app.get('/', (req, res) => {
    res.status(200).json({ message: 'Connected!' });
});

// Turn on that server!
const server = app.listen(3000, () => {
    console.log('App listening on port 3000');
});

module.exports = server;