Restful Testing

import pytest
from app import app

@pytest.fixture
def client():
    app.config['TESTING'] = True
    with app.test_client() as client:
        yield client

# Unit test: handler logic
def test_user_serialization():
    user = User(id=1, name="Alice", email="alice@example.com")
    result = user.to_dict()
    assert result['name'] == "Alice"
    assert 'email' in result

# Integration test: endpoint behavior
class TestUsersAPI:
    def test_list_users(self, client):
        response = client.get('/api/users')
        assert response.status_code == 200
        assert isinstance(response.json, list)

    def test_get_user_found(self, client):
        response = client.get('/api/users/1')
        assert response.status_code == 200
        assert response.json['id'] == 1

    def test_get_user_not_found(self, client):
        response = client.get('/api/users/999')
        assert response.status_code == 404
        assert 'error' in response.json

    def test_create_user_success(self, client):
        response = client.post('/api/users', json={
            'name': 'Bob', 'email': 'bob@example.com'
        })
        assert response.status_code == 201
        assert response.json['name'] == 'Bob'

    def test_create_user_validation_error(self, client):
        response = client.post('/api/users', json={})
        assert response.status_code == 422

    def test_create_user_missing_name(self, client):
        response = client.post('/api/users', json={'email': 'test@test.com'})
        assert response.status_code == 422
        assert any(e['field'] == 'name' for e in response.json['error']['details'])

// Jest API testing
const request = require('supertest');
const app = require('../app');

describe('Users API', () => {
  test('GET /api/users returns 200', async () => {
    const res = await request(app).get('/api/users');
    expect(res.status).toBe(200);
    expect(Array.isArray(res.body)).toBe(true);
  });

  test('GET /api/users/:id returns user', async () => {
    const res = await request(app).get('/api/users/1');
    expect(res.status).toBe(200);
    expect(res.body).toHaveProperty('id', 1);
    expect(res.body).toHaveProperty('name');
  });

  test('POST /api/users validates input', async () => {
    const res = await request(app)
      .post('/api/users')
      .send({ name: '' });
    expect(res.status).toBe(422);
    expect(res.body.error).toBeDefined();
  });
});