Django

Django Best Practices

Project Structure

Follow Django's app-based architecture. Each app should represent a distinct feature or domain concept. Keep apps small and focused -- if an app has 20+ models, it probably needs splitting.

Place reusable utilities in a core or common app. Keep settings.py clean by splitting into base.py, development.py, and production.py using a settings package.

Models

Define explicit Meta classes with ordering, verbose_name, and db_table where appropriate. Add __str__ methods to every model for admin and debugging readability.

Use model managers for complex queries rather than scattering filter() chains through views. Create custom querysets with as_manager() for chainable query methods.

Always create migrations after model changes with makemigrations. Review generated migration files before running them. Never edit migrations manually unless you understand the implications.

Views

Prefer class-based views (CBVs) for CRUD operations -- they eliminate boilerplate. Use function-based views for complex custom logic where CBV mixins would become contorted. In Django REST Framework, use ModelViewSet for standard CRUD and APIView for custom endpoints.

Keep views thin. Business logic belongs in services or model methods, not in views. A view should validate input, call a service, and return a response.

Security

Never expose raw model instances to API responses -- use serializers or forms to control which fields are visible. Always validate and clean form input. Use Django's CSRF protection and never disable it.

Set DEBUG = False in production. Configure ALLOWED_HOSTS explicitly. Use environment variables for SECRET_KEY and database credentials.

Database

Use select_related() for foreign key joins and prefetch_related() for reverse and many-to-many relationships to avoid N+1 query problems. Use Django Debug Toolbar in development to spot excessive queries.

Write data migrations for schema changes that need data transformation. Keep schema and data migrations separate.

Testing

Use TestCase for tests that need database access, SimpleTestCase for those that do not. Use factory_boy or model baker over fixtures for test data. Test views through the test client, not by calling view functions directly.

Source: calcosmic/Aether — distributed by TomeVault.