Task 1: Develop REST API - List Users / Add User

    require('dotenv').config()
    const express = require('express')
    const app = express()
    const port = process.env.PORT;
    console.log("PORT", port);
    app.use(express.json())

    // Create Connection Pool
    const mysql = require("mysql2/promise");

   const pool = mysql.createPool({
            host: process.env.DB_HOST,
            port: process.env.DB_PORT,
            user: process.env.DB_USERNAME,
            password: process.env.DB_PASSWORD,
            database: process.env.DB_DATABASE_NAME,
            connectionLimit: process.env.NO_OF_CONNECTIONS
    });


    // Create Routes
    app.get('/api', (req, res) => res.send('REST API is working!'));
    app.get('/api/users', getAllUsers);
    app.post('/api/users', createUser);

    async function getAllUsers(req,res){    
        const result = await pool.query("select * from users");    
        res.status(200).json(result[0]);
    }

    async function createUser(req,res){
        let user = req.body;
        let params = [ user.name, user.email, user.password, user.role];
        const result = await pool.query("insert into users (name,email,password,role) values ( ?,?,?,?)", params);    
        res.status(201).json({id:result[0].insertId});        
    }

    // Create Commmon Error Handler
    app.use(function (err, req, res, next) {
        console.log("common error handler")
        console.error(err);
        res.status(500).json({errorMessage:err.message});
    })

    app.listen(port, () => console.log(`Server is listening on port ${port}!`));

Task 4: Run the Server

    nodemon app.js