from fastapi import FastAPI

app = FastAPI(docs_url="/documentation", redoc_url=None)


@app.get("/items/")
async def read_items():

from fastapi import FastAPI, Header

app = FastAPI()


@app.get("/items/")
async def read_items(
    strange_header: str | None = Header(default=None, convert_underscores=False),
):

from fastapi import APIRouter

router = APIRouter()


@router.post("/")
async def update_admin():

app.include_router(
    admin.router,
    prefix="/admin",
    tags=["admin"],
    dependencies=[Depends(get_token_header)],
    responses={418: {"description": "I'm a teapot"}},
)


@app.get("/")
async def root():

from fastapi import FastAPI, status

app = FastAPI()


@app.post("/items/", status_code=status.HTTP_201_CREATED)
async def create_item(name: str):

/// tip | 팁

Pydantic이 **Rust** 쪽에서 직렬화하므로, 반환 타입을 선언하지 않았을 때보다 훨씬 더 높은 **성능**을 얻을 수 있습니다.

///

### 비 async *경로 처리 함수* { #non-async-path-operation-functions }

`async`가 없는 일반 `def` 함수도 사용할 수 있으며, 동일하게 `yield`를 사용할 수 있습니다.

FastAPI가 이벤트 루프를 막지 않도록 올바르게 실행을 보장합니다.

이 경우 함수가 async가 아니므로 적절한 반환 타입은 `Iterable[Item]`입니다:

from typing import Annotated

from fastapi import Cookie, FastAPI

app = FastAPI()


@app.get("/items/")
async def read_items(ads_id: Annotated[str | None, Cookie()] = None):

    q: Annotated[str, Depends(query_extractor)],
    last_query: Annotated[str | None, Cookie()] = None,
):
    if not q:
        return last_query
    return q


@app.get("/items/")
async def read_query(
    query_or_default: Annotated[str, Depends(query_or_cookie_extractor)],
):

from typing import Annotated

from fastapi import FastAPI, Header

app = FastAPI()


@app.get("/items/")
async def read_items(user_agent: Annotated[str | None, Header()] = None):

from fastapi.middleware.trustedhost import TrustedHostMiddleware

app = FastAPI()

app.add_middleware(
    TrustedHostMiddleware, allowed_hosts=["example.com", "*.example.com"]
)


@app.get("/")
async def main():