Express routing — defining GET, POST, PUT, DELETE routes

HTTP Method Routing in Express

Express maps HTTP verbs directly to methods on the app object. Each method registers a handler for requests matching that verb and path.

Defining all four core routes

const express = require('express');
const app = express();
app.use(express.json());

let users = [{ id: 1, name: 'Alice' }];

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

app.post('/users', (req, res) => {
  const user = { id: Date.now(), ...req.body };
  users.push(user);
  res.status(201).json(user);
});

app.put('/users/:id', (req, res) => {
  const user = users.find(u => u.id === +req.params.id);
  if (!user) return res.status(404).json({ error: 'Not found' });
  Object.assign(user, req.body);
  res.json(user);
});

app.delete('/users/:id', (req, res) => {
  users = users.filter(u => u.id !== +req.params.id);
  res.status(204).send();
});

app.listen(3000);

Use app.route() to chain handlers for the same path and avoid repetition:

app.route('/users/:id')
  .get((req, res) => { /* ... */ })
  .put((req, res) => { /* ... */ })
  .delete((req, res) => { /* ... */ });

Always return correct status codes: 200 (OK), 201 (Created), 204 (No Content), 404 (Not Found).