This skill guides the creation of modular, organized FastAPI routers, emphasizing maintainability and scalability.
Routing Strategies
1. Modular Router Pattern (Standard)
The most common and recommended approach for FastAPI.
Structure:
src/api/v1/endpoints/
├── users.py
├── items.py
└── auth.py
Implementation:
src/api/v1/endpoints/users.py:
from fastapi import APIRouter
router = APIRouter()
@router.get("/")
async def get_users():
...
src/api/v1/api.py (Aggregator):
from fastapi import APIRouter
from src.api.v1.endpoints import users, items
api_router = APIRouter()
api_router.include_router(users.router, prefix="/users", tags=["users"])
api_router.include_router(items.router, prefix="/items", tags=["items"])
2. File-Based Routing (fastapi-router)
For a Next.js-like experience where file structure dictates URLs. (Requires fastapi-router library or custom walker).
Structure:
src/app/
├── api/
│ ├── users/
│ │ ├── route.py # Handles /api/users
│ │ └── [id]/
│ │ └── route.py # Handles /api/users/{id}
Best Practices
- Prefixing: Use prefixes at the router include level, not inside every endpoint decorator.
- Tags: Use tags to group endpoints in OpenAPI docs.
- Dependencies: Apply dependencies (like auth) at the router level if they apply to all endpoints in that router.
router = APIRouter(dependencies=[Depends(get_current_active_user)]) - Version: Namespace routers by API version (
v1,v2).