social-media/config/database.js

const mongoose = require('mongoose'),
    config = require('./config').getConfig();

// Mongo Connection Class
class Connection {
    constructor() {
        const url = config.MONGO_URL || 'mongodb://localhost:27017/social_media';

        this.connect(url).then(() => {
            console.log('✔ Database Connected');
        }).catch((err) => {
            console.error('✘ MONGODB ERROR: ', err.message);
        });

    }

    async connect(url) {
        try {
            await mongoose.connect(url);
        } catch (e) {
            throw e;
        }
    }
}

module.exports = new Connection();