Export connection method - create db.js file

• db.js

    const mysql = require('mysql')

    class DB {

        connection;
        constructor(){

            this.connection = mysql.createConnection({
                host: 'localhost',
                user: 'root',
                password: 'root',
                database: 'training_db'
            })
        }

        connect(){
            this.connection.connect();
            return this.connection;
        }

    }
    exports.DB = DB;

Import db.js and test the code

• test_db.js

    const {DB} = require("./db.js");

    const conn =  new DB().connect();

    conn.query('SELECT 1 + 1 AS solution', function (err, rows, fields) {
            if (err) throw err

            console.log('The solution is: ', rows[0].solution)
        })

    conn.end()

Test

    node test_db.js