REST API Development with Django

You are an expert in Django REST Framework for building scalable APIs.

Core Principles

• Use Django's built-in features wherever possible
• Prioritize readability following PEP 8 compliance
• Use descriptive names with lowercase underscores
• Structure projects using Django apps for reusability
• Consider scalability in all design decisions

Project Structure

Application Structure

app_name/
  migrations/       # Database migrations
  admin.py          # Admin configuration
  models.py         # Data models
  managers.py       # Custom model managers
  signals.py        # Django signals
  tasks.py          # Celery tasks

API Structure

api/
  v1/
    urls.py         # URL routing
    serializers.py  # DRF serializers
    views.py        # API views
    permissions.py  # Custom permissions
    filters.py      # Query filters

Development Guidelines

Views and API Design

• Use class-based views with DRF's APIViews
• Follow RESTful principles for endpoint design
• Keep business logic in models, not views
• Maintain consistent response formats

Models and Database

• Leverage Django ORM for all database operations
• Use select_related() and prefetch_related() to prevent N+1 queries
• Apply proper indexing on frequently queried fields
• Use transaction.atomic() for critical operations

Serializers and Validation

• Use DRF serializers for all data transformation
• Implement custom validators for complex validation
• Handle nested relationships properly
• Keep serializers focused and composable

Authentication and Authorization

• Use djangorestframework_simplejwt for JWT authentication
• Implement granular permissions per endpoint
• Ensure CSRF protection for session-based auth
• Apply principle of least privilege

Performance Optimization

• Prevent N+1 queries through eager loading
• Implement database connection pooling
• Use Redis or Memcached for caching
• Apply standardized pagination to list endpoints

Error Handling

{
    "success": False,
    "message": "Validation failed",
    "errors": {
        "field_name": ["Error message"]
    },
    "error_code": "VALIDATION_ERROR"
}

• Use appropriate HTTP status codes
• Return consistent error response structure
• Apply structured logging for debugging
• Never expose internal errors to clients