]

app.add_middleware(
    CORSMiddleware,
    allow_origins=origins,
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)


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

class CommonHeaders(BaseModel):
    host: str
    save_data: bool
    if_modified_since: Union[str, None] = None
    traceparent: Union[str, None] = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(headers: CommonHeaders = Header()):

class Cookies(BaseModel):
    class Config:
        extra = "forbid"

    session_id: str
    fatebook_tracker: Union[str, None] = None
    googall_tracker: Union[str, None] = None


@app.get("/items/")
async def read_items(cookies: Annotated[Cookies, Cookie()]):

        ),
        ("/items", {"session": "cookiesession"}, 200, {"ads_id": None}),
    ],
)
def test(path, cookies, expected_status, expected_response):
    client = TestClient(app, cookies=cookies)
    response = client.get(path)
    assert response.status_code == expected_status
    assert response.json() == expected_response


def test_openapi_schema():
    client = TestClient(app)
    response = client.get("/openapi.json")

            userData[key] = value
        }
    }

    ClassPool instanceScopedPool = new ClassPool()

    JApiClass apiClass = Stub(JApiClass)

    def setup() {
        instanceScopedPool.appendSystemPath()
    }

    void noViolation(def rule) {
        assert rule.maybeViolation(apiClass) == null
    }

    Map getInitializationParams() {
        return [acceptedApiChanges: [:],

**FastAPI** は、`BackgroundTasks` 型のオブジェクトを作成し、そのパラメーターに渡します。

## タスク関数の作成

バックグラウンドタスクとして実行される関数を作成します。

これは、パラメーターを受け取ることができる単なる標準的な関数です。

これは `async def` または通常の `def` 関数であり、**FastAPI** はこれを正しく処理します。

ここで、タスク関数はファイル書き込みを実行します (メール送信のシミュレーション)。

また、書き込み操作では `async` と `await` を使用しないため、通常の `def` で関数を定義します。

```Python hl_lines="6-9"
{!../../docs_src/background_tasks/tutorial001.py!}
```

## バックグラウンドタスクの追加

    "baz": {"name": "Baz", "description": None, "price": 50.2, "tax": 10.5, "tags": []},
}


@app.get("/items/{item_id}", response_model=Item, response_model_exclude_unset=True)
async def read_item(item_id: str):

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,
    item: Item = Body(
        examples=[
            {
                "name": "Foo",
                "description": "A very nice Item",
                "price": 35.4,

from fastapi.testclient import TestClient

from docs_src.advanced_middleware.tutorial001 import app


def test_middleware():
    client = TestClient(app, base_url="https://testserver")
    response = client.get("/")
    assert response.status_code == 200, response.text

    client = TestClient(app)
    response = client.get("/", follow_redirects=False)
    assert response.status_code == 307, response.text

    description: Union[str, None] = None
    price: float
    tax: Union[float, None] = None
    tags: set[str] = set()


@app.post("/items/", response_model=Item, status_code=status.HTTP_201_CREATED)
async def create_item(item: Item):