To create a REST API, define routes for CRUD operations and handle requests appropriately.
Example:
const express = require('express');
const app = express();
app.use(express.json());
let items = [];
app.get('/items', (req, res) => res.json(items));
app.post('/items', (req, res) => {
items.push(req.body);
res.status(201).json(req.body);
});
app.put('/items/:id', (req, res) => {
const item = items[req.params.id];
items[req.params.id] = { ...item, ...req.body };
res.json(items[req.params.id]);
});
app.delete('/items/:id', (req, res) => {
items.splice(req.params.id, 1);
res.status(204).send();
});
app.listen(3000, () => console.log('API running on http://localhost:3000'));