Node.Js Express CRUD template

//npm init

//npm install nodemon, mysql2, express, cors





const express = require('express');

const mysql = require('mysql2/promise');

const cors = require('cors');



const app = express();



app.use(cors());

app.use(express.json());



const dbPool = mysql.createPool({

    host: 'localhost',     

    user: 'root',         

    password:  '',

    database: 'database_name', 

    port: 3306,         

});





app.get('/', (req, res) => {

  res.send('Backend running');

});







// -------------- CRUD --------------



// CREATE

app.post('/api/users', async (req, res) => {

    try {

        const { name, email } = req.body;



        if (!name || !email) {

            return res.status(400).json({ error: 'Error for the frontend (name or email missing)' });

        }



        const sql = "INSERT INTO users (name, email) VALUES (?, ?)";

        const [result] = await dbPool.query(sql, [name, email]);

        res.status(201).json({ message: "Response for the frontend", id: result.insertId });

    } catch (error) {

        console.error("Error for the backend ", error);

        res.status(500).json({ error: 'Error for the frontend' });

    }

});



// READ 

app.get('/api/users', async (req, res) => {

    try {

        const sql = "SELECT id, name, email FROM users";

        const [result] = await dbPool.query(sqlQuery);

        res.json(result);

    } catch (error) {

        console.error("Error for the backend ", error);

        res.status(500).json({ error: 'Error for the frontend' });

    }

});





// UPDATE

app.patch('/api/users/:id', async (req, res) => {

    try {

        const { id } = req.params;

        const { name, email } = req.body;



        if (!name || !email) {

             return res.status(400).json({ error: 'Error for the frontend (name or email missing)' });

        }



        const sql = "UPDATE users SET name = ?, email = ? WHERE id = ?";

        const [result] = await dbPool.query(sql, [name, email, id]);



         res.status(201).json({ message: "Response for the frontend", id: result.insertId });

    } catch (error) {

        console.error("Error for the backend ", error);

        res.status(500).json({ error: 'Error for the frontend' });

    }

});



// DELETE 

app.delete('/api/users/:id', async (req, res) => {

    try {

        const { id } = req.params;

        const sql = "DELETE FROM users WHERE id = ?";

        const [result] = await dbPool.query(sql, [id]);



       res.status(201).json({ message: "Response for the frontend", id: result.insertId });

    } catch (error) {

        console.error("Error for the backend ", error);

        res.status(500).json({ error: 'Error for the frontend' });

    }

});



const PORT = 3001;



app.listen(PORT, () => {

  console.log('Server is running on: http://localhost:'+PORT);

});