Testing with API Clients

1# learnhub.http — VS Code REST Client
2@baseUrl = http://localhost:3000
3

4### Login
5# @name login
6POST {{baseUrl}}/api/auth/login
7Content-Type: application/json
8

9{ "email": "ravi@example.com", "password": "learn-node-2026" }
10

11### Create a course with the token from the login response
12POST {{baseUrl}}/api/courses
13Authorization: Bearer {{login.response.body.accessToken}}
14Content-Type: application/json
15

16{ "title": "Testing APIs", "price": 299 }

1import express from 'express';
2

3// ── The API under test (normally your real app, already running) ──
4const app = express();
5app.use(express.json());
6const courses = [];
7app.post('/api/auth/login', (req, res) =>
8  req.body.password === 'learn-node-2026' ? res.json({ accessToken: 'demo-token-123' }) : res.status(401).json({ error: 'Invalid email or password' }));
9app.post('/api/courses', (req, res) => {
10  if (req.get('authorization') !== 'Bearer demo-token-123') return res.status(401).json({ error: 'Authentication required' });
11  const course = { id: courses.length + 1, ...req.body };
12  courses.push(course);
13  res.status(201).location(`/api/courses/${course.id}`).json(course);
14});
15app.get('/api/courses/:id', (req, res) => {
16  const course = courses.find(c => c.id === Number(req.params.id));
17  course ? res.json(course) : res.status(404).json({ error: 'Not found' });
18});
19

20// ── The "collection": environment, requests and tests ──
21const env = { baseUrl: 'http://localhost:3116' };            // like a Postman environment
22let passed = 0, failed = 0;
23const expect = (name, condition) => {
24  condition ? passed++ : failed++;
25  console.log(`  ${condition ? '✓' : '✗'} ${name}`);
26};
27async function send(name, method, path, { body, auth } = {}) {
28  console.log(`${method} ${path}  (${name})`);
29  const res = await fetch(env.baseUrl + path, {
30    method,
31    headers: { 'Content-Type': 'application/json', ...(auth && { Authorization: `Bearer ${env.token}` }) },
32    body: body && JSON.stringify(body),
33  });
34  return { status: res.status, headers: res.headers, json: await res.json() };
35}
36

37const server = app.listen(3116, async () => {
38  let r = await send('login', 'POST', '/api/auth/login', { body: { email: 'ravi@example.com', password: 'learn-node-2026' } });
39  expect('status is 200', r.status === 200);
40  expect('returns an access token', typeof r.json.accessToken === 'string');
41  env.token = r.json.accessToken;                             // like pm.environment.set('token', …)
42

43  r = await send('create course', 'POST', '/api/courses', { auth: true, body: { title: 'Testing APIs', price: 299 } });
44  expect('status is 201', r.status === 201);
45  expect('Location points to the new course', r.headers.get('location') === `/api/courses/${r.json.id}`);
46  env.courseId = r.json.id;
47

48  r = await send('read it back', 'GET', `/api/courses/${env.courseId}`);
49  expect('title round-trips', r.json.title === 'Testing APIs');
50

51  r = await send('create without token', 'POST', '/api/courses', { body: { title: 'Nope' } });
52  expect('status is 401', r.status === 401);
53

54  console.log(`${passed} passed, ${failed} failed`);
55  process.exitCode = failed ? 1 : 0;                          // CI fails if any check fails
56  server.close();
57});

POST /api/auth/login  (login)
  ✓ status is 200
  ✓ returns an access token
POST /api/courses  (create course)
  ✓ status is 201
  ✓ Location points to the new course
GET /api/courses/1  (read it back)
  ✓ title round-trips
POST /api/courses  (create without token)
  ✓ status is 401
6 passed, 0 failed