.cursorrules Python FastAPI copy # Python FastAPI .cursorrules # FastAPI best practices fastapi_best_practices = [ "Use Pydantic models for request and response schemas", "Implement dependency injection for shared resources", "Utilize async/await for non-blocking operations", "Use path operations decorators (@app.get, @app.post, etc.)", "Implement proper error handling with HTTPException", "Use FastAPI's built-in OpenAPI and JSON Schema support", ] # Folder structure folder_structure = """ app/ main.py models/ schemas/ routers/ dependencies/ services/ tests/ """ # Additional instructions additional_instructions = """ 1. Use type hints for all function parameters and return values 2. Implement proper input validation using Pydantic 3. Use FastAPI's background tasks for long-running operations 4. Implement proper CORS handling 5. Use FastAPI's security utilities for authentication 6. Follow PEP 8 style guide for Python code 7. Implement comprehensive unit and integration tests """ --- description: Enforces FastAPI best practices for application code within the 'app' directory, including data validation, dependency injection, and asynchronous operations. globs: app/**/*.* --- - Use Pydantic models for request and response schemas - Implement dependency injection for shared resources - Utilize async/await for non-blocking operations - Use path operations decorators (@app.get, @app.post, etc.) - Implement proper error handling with HTTPException - Use FastAPI's built-in OpenAPI and JSON Schema support --- description: Defines the recommended folder structure for FastAPI projects to maintain organization and separation of concerns within the 'app' directory. globs: app/**/*.* --- - Follow this folder structure: app/ main.py models/ schemas/ routers/ dependencies/ services/ tests/ --- description: Specifies guidelines for the main application file in FastAPI projects, focusing on application initialization and configuration. globs: app/main.py --- - Ensure proper application initialization with FastAPI() - Configure middleware and exception handlers - Define API routes using path operation decorators --- description: Guidelines for defining Pydantic models within the models directory of a FastAPI project to ensure data validation and serialization. globs: app/models/*.py --- - Use Pydantic models for request and response schemas - Define data types using Pydantic fields - Implement validation logic using Pydantic validators --- description: Applies general Python coding standards, including type hinting, input validation with Pydantic, background tasks, CORS handling, security utilities, PEP 8 compliance, and comprehensive testing. globs: **/*.py --- - Use type hints for all function parameters and return values - Implement proper input validation using Pydantic - Use FastAPI's background tasks for long-running operations - Implement proper CORS handling - Use FastAPI's security utilities for authentication - Follow PEP 8 style guide for Python code - Implement comprehensive unit and integration tests Cursor AI by @PatrickJS
.cursorrrules Python 3.12 FastAPI Best Practices copy Here are some best practices and rules you must follow: - You use Python 3.12 - Frameworks: - pydantic - fastapi - sqlalchemy - You use poetry for dependency management - You use alembic for database migrations - You use fastapi-users for user management - You use fastapi-jwt-auth for authentication - You use fastapi-mail for email sending - You use fastapi-cache for caching - You use fastapi-limiter for rate limiting - You use fastapi-pagination for pagination 1. **Use Meaningful Names**: Choose descriptive variable, function, and class names. 2. **Follow PEP 8**: Adhere to the Python Enhancement Proposal 8 style guide for formatting. 3. **Use Docstrings**: Document functions and classes with docstrings to explain their purpose. 4. **Keep It Simple**: Write simple and clear code; avoid unnecessary complexity. 5. **Use List Comprehensions**: Prefer list comprehensions for creating lists over traditional loops when appropriate. 6. **Handle Exceptions**: Use try-except blocks to handle exceptions gracefully. 7. **Use Virtual Environments**: Isolate project dependencies using virtual environments (e.g., `venv`). 8. **Write Tests**: Implement unit tests to ensure code reliability. 9. **Use Type Hints**: Utilize type hints for better code clarity and type checking. 10. **Avoid Global Variables**: Limit the use of global variables to reduce side effects. These rules will help you write clean, efficient, and maintainable Python code. Cursor AI by @Raphael Mansuy
.cursorrules PY fast API copy You are an expert in Python, FastAPI, and scalable API development. Key Principles - Write concise, technical responses with accurate Python examples. - Use functional, declarative programming; avoid classes where possible. - Prefer iteration and modularization over code duplication. - Use descriptive variable names with auxiliary verbs (e.g., is_active, has_permission). - Use lowercase with underscores for directories and files (e.g., routers/user_routes.py). - Favor named exports for routes and utility functions. - Use the Receive an Object, Return an Object (RORO) pattern. Python/FastAPI - Use def for pure functions and async def for asynchronous operations. - Use type hints for all function signatures. Prefer Pydantic models over raw dictionaries for input validation. - File structure: exported router, sub-routes, utilities, static content, types (models, schemas). - Avoid unnecessary curly braces in conditional statements. - For single-line statements in conditionals, omit curly braces. - Use concise, one-line syntax for simple conditional statements (e.g., if condition: do_something()). Error Handling and Validation - Prioritize error handling and edge cases: - Handle errors and edge cases at the beginning of functions. - Use early returns for error conditions to avoid deeply nested if statements. - Place the happy path last in the function for improved readability. - Avoid unnecessary else statements; use the if-return pattern instead. - Use guard clauses to handle preconditions and invalid states early. - Implement proper error logging and user-friendly error messages. - Use custom error types or error factories for consistent error handling. Dependencies - FastAPI - Pydantic v2 - Async database libraries like asyncpg or aiomysql - SQLAlchemy 2.0 (if using ORM features) FastAPI-Specific Guidelines - Use functional components (plain functions) and Pydantic models for input validation and response schemas. - Use declarative route definitions with clear return type annotations. - Use def for synchronous operations and async def for asynchronous ones. - Minimize @app.on_event("startup") and @app.on_event("shutdown"); prefer lifespan context managers for managing startup and shutdown events. - Use middleware for logging, error monitoring, and performance optimization. - Optimize for performance using async functions for I/O-bound tasks, caching strategies, and lazy loading. - Use HTTPException for expected errors and model them as specific HTTP responses. - Use middleware for handling unexpected errors, logging, and error monitoring. - Use Pydantic's BaseModel for consistent input/output validation and response schemas. Performance Optimization - Minimize blocking I/O operations; use asynchronous operations for all database calls and external API requests. - Implement caching for static and frequently accessed data using tools like Redis or in-memory stores. - Optimize data serialization and deserialization with Pydantic. - Use lazy loading techniques for large datasets and substantial API responses. Key Conventions 1. Rely on FastAPI’s dependency injection system for managing state and shared resources. 2. Prioritize API performance metrics (response time, latency, throughput). 3. Limit blocking operations in routes: - Favor asynchronous and non-blocking flows. - Use dedicated async functions for database and external API operations. - Structure routes and dependencies clearly to optimize readability and maintainability. Refer to FastAPI documentation for Data Models, Path Operations, and Middleware for best practices. Cursor AI by @Caio Barbieri
