API Testing & Documentation

API Testing & Docs

• APITestCase: self.client.post('/api/users/', data, format='json') — test API endpoints with DRF's test client. self.client.credentials(HTTP_AUTHORIZATION='Token ' + token) for authenticated tests
• Request Factory: APIRequestFactory — create requests without going through URL routing. Faster unit tests. Combine with force_authenticate() for testing specific views in isolation
• API Documentation: drf-spectacular generates OpenAPI 3.0 schema — Swagger UI and ReDoc frontends. @extend_schema decorator for customizing endpoint documentation
• API Versioning: URLPathVersioning (/api/v1/users/), AcceptHeaderVersioning (Accept: application/json; version=1), NamespaceVersioning. Support multiple versions during migration periods
• Hyperlinked APIs: HyperlinkedModelSerializer — returns URLs instead of IDs for relationships. HATEOAS (Hypermedia) approach. Clients follow links instead of constructing URLs
• Best Practices: Use ViewSets for standard CRUD. Custom actions with @action decorator. Consistent error response format. Rate limit public endpoints. Version from day one

Try It Yourself: REST API Design

# Django REST Framework Pattern

from dataclasses import dataclass

@dataclass
class Product:
    id: int
    name: str
    price: float
    category: str

products = [
    Product(1, "Laptop", 999.99, "Electronics"),
    Product(2, "Headphones", 79.99, "Electronics"),
    Product(3, "Python Book", 39.99, "Books"),
]

def serialize(p):
    return {"id": p.id, "name": p.name, "price": p.price}

def list_products(cat=None):
    items = [p for p in products if not cat or p.category == cat]
    return [serialize(p) for p in items]

print("All products:")
for p in list_products():
    print(f"  {p[#ce9178">'name']}: {p['price']} USD")

print("
Electronics:")
for p in list_products("Electronics"):
    print(f"  {p[#ce9178">'name']}: {p['price']} USD")

Quick Quiz — DRF