Cara Buat REST API dengan Node.js dan Express

mkdir my-api && cd my-api
npm init -y
npm install express dotenv cors helmet morgan

const express = require('express');
const app = express();
const PORT = process.env.PORT || 3000;

app.use(express.json());

app.get('/', (req, res) => {
  res.json({ message: 'API is running!' });
});

app.listen(PORT, () => {
  console.log(`Server running on port ${PORT}`);
});

// GET all
app.get('/api/users', (req, res) => {
  res.json(users);
});

// GET single
app.get('/api/users/:id', (req, res) => {
  const user = users.find(u => u.id === parseInt(req.params.id));
  if (!user) return res.status(404).json({ error: 'Not found' });
  res.json(user);
});

// POST create
app.post('/api/users', (req, res) => {
  const newUser = { id: nextId++, ...req.body };
  users.push(newUser);
  res.status(201).json(newUser);
});

// PUT update
app.put('/api/users/:id', (req, res) => {
  const index = users.findIndex(u => u.id === parseInt(req.params.id));
  if (index === -1) return res.status(404).json({ error: 'Not found' });
  users[index] = { ...users[index], ...req.body };
  res.json(users[index]);
});

// DELETE
app.delete('/api/users/:id', (req, res) => {
  const index = users.findIndex(u => u.id === parseInt(req.params.id));
  if (index === -1) return res.status(404).json({ error: 'Not found' });
  users.splice(index, 1);
  res.status(204).send();
});