FastAPI RESTful API Builder Skill

This skill helps you build robust and scalable RESTful APIs using FastAPI. It provides a boilerplate project and documentation on best practices.

Quickstart

To create a new FastAPI project, copy the boilerplate project from the

assets/fastapi-boilerplate

directory.

cp -r assets/fastapi-boilerplate /path/to/your/new/project

This boilerplate includes:

• A recommended project structure with

  app/routers

  ,

  app/models

  ,

  app/schemas

  , and

  app/services

  .
• A working example of a CRUD API for an

  items

  resource.
• SQLAlchemy integration with a SQLite database.
• Pydantic models for request and response validation.

Core Concepts and Patterns

This skill promotes a set of best practices for FastAPI development. For detailed explanations and code examples, refer to the following documents in the

references/

directory.

• CRUD Router Template: A template for creating CRUD endpoints for a resource.
• Pydantic Schemas for Validation: How to use Pydantic for data validation and serialization.
• Service Layer Pattern: How to separate business logic from the API layer.
• Dependency Injection: How to use FastAPI's dependency injection system.
• Advanced Features: Covers background tasks, file uploads, and pagination.

Asynchronous Operations

FastAPI is built on

asyncio

and supports asynchronous code using

async

and

await

. This is crucial for I/O-bound operations like database queries or external API calls, as it allows your server to handle multiple requests concurrently without blocking.

When defining your path operations, you can use

async def

:

@app.get("/")
async def read_root():
    # Asynchronous database call
    results = await db.fetch_all("SELECT * FROM items")
    return results

Ensure that any I/O-bound libraries you use have async support (e.g.,

databases

,

httpx

).