Cursor Rules Generator for Python + Django

Generate a production-ready .cursorrules configuration file for a Python Django project with the following specifications:

Project Details

• Python Version: 3.11+
• Django Version: [Specify version, e.g., 4.2 or 5.0]
• Project Type: [web application / REST API / full-stack app]
• Database: [PostgreSQL / MySQL / SQLite]
• Additional Tools: Black (formatting), mypy (type checking), pytest-django (testing)

Code Standards to Enforce

Python Requirements

• Use type hints following PEP 484 for all function signatures
• Follow PEP 8 style guide strictly
• Use Black for code formatting (line length: 88 characters)
• Enable mypy strict mode for type checking
• Python 3.11+ syntax and features

Django Model Patterns

• Create abstract base models for common fields (created_at, updated_at, etc.)
• Always implement __str__() and __repr__() methods
• Include Meta class with ordering and verbose_name
• Use descriptive related_name for all ForeignKey and ManyToMany relationships
• Add database indexes on frequently queried fields
• Use choices with TextChoices or IntegerChoices enums

Django View Patterns

• Prefer class-based views over function-based views
• Use mixins for reusable view logic (e.g., LoginRequiredMixin, PermissionRequiredMixin)
• Leverage generic views (ListView, DetailView, CreateView, etc.) when applicable
• Always implement proper permission checks
• Use get_queryset() method to customize query logic
• Return proper HTTP status codes

URL Configuration

• Use descriptive URL names for all routes
• Use path() instead of deprecated url()
• Include app namespaces for all app-level URLs
• Follow RESTful naming conventions for API endpoints
• Group related URLs logically

File Structure

Generate rules for this project structure:

myproject/
├── apps/
│   ├── users/
│   ├── core/
│   └── api/
├── config/
│   ├── settings/
│   │   ├── base.py
│   │   ├── development.py
│   │   └── production.py
│   └── urls.py
├── templates/
└── static/

QuerySet Optimization

• Always use select_related() for forward ForeignKey relationships
• Always use prefetch_related() for reverse ForeignKey and ManyToMany relationships
• Prevent N+1 query problems
• Use only() and defer() strategically to load only needed fields
• Add .count() instead of len() on querysets
• Use exists() for boolean checks instead of counting

Security Requirements

• Never commit SECRET_KEY or sensitive credentials
• Use environment variables for all configuration
• Ensure CSRF protection is enabled
• Use Django ORM to prevent SQL injection
• Enable XSS protection in templates (autoescaping on)
• Validate and sanitize all user input
• Use Django's built-in password hashers
• Implement rate limiting for authentication endpoints

Testing Standards

• Write unit tests for all views and business logic
• Test all model methods and properties
• Use pytest-django as the testing framework
• Use Factory Boy for test data generation
• Aim for 80%+ code coverage
• Test both success and error cases
• Mock external API calls

Performance Optimization

• Add database indexes on fields used in filters and ordering
• Implement query optimization with select_related/prefetch_related
• Use caching strategy with Redis for expensive queries
• Use async views for I/O-bound operations (Django 4.1+)
• Paginate large querysets
• Use database-level constraints when possible

API Development (if applicable)

• Use Django REST Framework for API endpoints
• Implement proper serializer validation
• Use ViewSets and Routers for standard CRUD
• Add pagination to list endpoints
• Implement proper authentication (JWT, Session, or Token)
• Use throttling to prevent abuse
• Version your API (e.g., /api/v1/)

Additional Requirements

Include rules for:

• Import ordering (standard library, third-party, local)
• Docstring style (Google or NumPy format)
• Error handling patterns
• Logging configuration
• Environment-specific settings management

Generate the complete .cursorrules file that will guide Cursor IDE to follow these Django best practices consistently.