それでも、どちらの状況でも、**FastAPI**が過去のフレームワークよりも (またはそれに匹敵するほど) [高速になる](index.md#_10){.internal-link target=_blank}可能性があります。

### 依存関係

依存関係についても同様です。依存関係が `async def` ではなく標準の `def` 関数である場合、外部スレッドプールで実行されます。

### サブ依存関係

(関数定義のパラメーターとして) 相互に必要な複数の依存関係とサブ依存関係を設定できます。一部は `async def` で作成され、他の一部は通常の `def` で作成されます。それでも動作し、通常の `def`で作成されたものは、「awaitされる」代わりに (スレッドプールから) 外部スレッドで呼び出されます。

@pytest.fixture(name="client")
def get_client():
    from docs_src.request_forms.tutorial001 import app

    client = TestClient(app)
    return client


def test_post_body_form(client: TestClient):
    response = client.post("/login/", data={"username": "Foo", "password": "secret"})
    assert response.status_code == 200
    assert response.json() == {"username": "Foo"}

async def context_b(state: dict = Depends(context_a)):
    state["context_b"] = "started b"
    try:
        yield state
    finally:
        state["context_b"] = f"finished b with a: {state['context_a']}"


@app.get("/async")
async def get_async(state: str = Depends(asyncgen_state)):
    return state


@app.get("/sync")
async def get_sync(state: str = Depends(generator_state)):

from dirty_equals import IsDict
from fastapi.testclient import TestClient

from ...utils import needs_py310


@pytest.fixture(name="client")
def get_client():
    from docs_src.query_params.tutorial006_py310 import app

    c = TestClient(app)
    return c


@needs_py310
def test_foo_needy_very(client: TestClient):
    response = client.get("/items/foo?needy=very")
    assert response.status_code == 200

        use_kwargs = {k: v for k, v in kwargs.items() if v is not _Unset}

        super().__init__(**use_kwargs)

    def __repr__(self) -> str:
        return f"{self.__class__.__name__}({self.default})"


class Path(Param):
    in_ = ParamTypes.path

    def __init__(
        self,
        default: Any = ...,
        *,
        default_factory: Union[Callable[[], Any], None] = _Unset,

from fastapi import FastAPI
from fastapi.testclient import TestClient


@pytest.fixture(name="app")
def get_app():
    from docs_src.request_forms_and_files.tutorial001_an import app

    return app


@pytest.fixture(name="client")
def get_client(app: FastAPI):
    client = TestClient(app)
    return client


def test_post_form_no_body(client: TestClient):
    response = client.post("/files/")

        List<String> errors = []

        def inspectParametersNullabilityOf = { CtBehavior oldBehavior, CtBehavior newBehavior ->

            List<Boolean> oldParametersNullability = parametersNullabilityOf(oldBehavior)
            List<Boolean> newParametersNullability = parametersNullabilityOf(newBehavior)

            for (int idx = 0; idx < oldParametersNullability.size(); idx++) {
                def oldNullability = oldParametersNullability[idx]

    Again, you can combine `dataclasses` with standard type annotations.

8. Notice that this *path operation function* uses regular `def` instead of `async def`.

    As always, in FastAPI you can combine `def` and `async def` as needed.

app = FastAPI()


def verify_password(plain_password, hashed_password):
    return pwd_context.verify(plain_password, hashed_password)


def get_password_hash(password):
    return pwd_context.hash(password)


def get_user(db, username: str):
    if username in db:
        user_dict = db[username]
        return UserInDB(**user_dict)


def authenticate_user(fake_db, username: str, password: str):

import pytest
from dirty_equals import IsDict
from fastapi.testclient import TestClient


@pytest.fixture(name="client")
def get_client():
    from docs_src.body_multiple_params.tutorial001_an import app

    client = TestClient(app)
    return client


def test_post_body_q_bar_content(client: TestClient):
    response = client.put("/items/5?q=bar", json={"name": "Foo", "price": 50.5})
    assert response.status_code == 200