npm install expressnpm install -D @types/express

// src/server.tsimport express from 'express'; const app = express();const PORT = process.env.PORT || 3000; // JSON middlewareapp.use(express.json()); // First routeapp.get('/', (req, res) => {  res.json({ message: 'Welcome to E-commerce API!' });}); app.listen(PORT, () => {  console.log(`🚀 Server running on http://localhost:${PORT}`);});

npm run dev

// GET - Fetch dataapp.get('/products', (req, res) => {  res.json([{ id: 1, name: 'iPhone' }]);}); // POST - Create dataapp.post('/products', (req, res) => {  const { name, price } = req.body;  res.status(201).json({ id: 2, name, price });}); // PUT - Update completelyapp.put('/products/:id', (req, res) => {  const { id } = req.params;  res.json({ id, ...req.body });}); // DELETE - Removeapp.delete('/products/:id', (req, res) => {  res.status(204).send();});

app.get('/products/:id', (req, res) => {  // URL parameters  const { id } = req.params;   // Query string (?page=1&limit=10)  const { page, limit } = req.query;   // Request body (POST, PUT)  const body = req.body;   // Request headers  const auth = req.headers.authorization;   // JSON response  res.status(200).json({    success: true,    data: { id, page, limit }  });});