log.write(message)


def get_query(background_tasks: BackgroundTasks, q: Union[str, None] = None):
    if q:
        message = f"found query: {q}\n"
        background_tasks.add_task(write_log, message)
    return q


@app.post("/send-notification/{email}")
async def send_notification(
    email: str, background_tasks: BackgroundTasks, q: Annotated[str, Depends(get_query)]
):
    message = f"message to {email}\n"

app = FastAPI()


def query_extractor(q: str | None = None):
    return q


def query_or_cookie_extractor(
    q: str = Depends(query_extractor), last_query: str | None = Cookie(default=None)
):
    if not q:
        return last_query
    return q


@app.get("/items/")
async def read_query(query_or_default: str = Depends(query_or_cookie_extractor)):

app = FastAPI()


def query_extractor(q: Union[str, None] = None):
    return q


def query_or_cookie_extractor(
    q: str = Depends(query_extractor),
    last_query: Union[str, None] = Cookie(default=None),
):
    if not q:
        return last_query
    return q


@app.get("/items/")
async def read_query(query_or_default: str = Depends(query_or_cookie_extractor)):

app = FastAPI()


def query_extractor(q: str | None = None):
    return q


def query_or_cookie_extractor(
    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)],
):

    * Она зависит от `query_extractor` и присваивает возвращаемое ей значение параметру `q`.
* Она также объявляет необязательный куки-параметр `last_query` в виде строки.
    * Если пользователь не указал параметр `q` в запросе, то мы используем последний использованный запрос, который мы ранее сохранили в куки-параметре `last_query`.

## Использование зависимости

Затем мы можем использовать зависимость вместе с:

//// tab | Python 3.10+

	<include path="fess.xml"/>
	<include path="fess_api.xml"/>
	<include path="fess_cors.xml"/>
	<include path="fess_dict.xml"/>
	<include path="fess_job.xml"/>
	<include path="fess_ldap.xml"/>
	<include path="fess_query.xml"/>
	<include path="fess_rankfusion.xml"/>
	<include path="fess_score.xml"/>
	<include path="fess_sso.xml"/>
	<include path="fess_thumbnail.xml"/>

	<include path="crawler/client.xml" />

```

////

➡️ 🎯 🔛 🔢 📣:

* ✋️ 👉 🔢 🔗 ("☑") ⚫️, ⚫️ 📣 ➕1️⃣ 🔗 (⚫️ "🪀" 🔛 🕳 🙆).
    * ⚫️ 🪀 🔛 `query_extractor`, & 🛠️ 💲 📨 ⚫️ 🔢 `q`.
* ⚫️ 📣 📦 `last_query` 🍪, `str`.
    * 🚥 👩‍💻 🚫 🚚 🙆 🔢 `q`, 👥 ⚙️ 🏁 🔢 ⚙️, ❔ 👥 🖊 🍪 ⏭.

## ⚙️ 🔗

⤴️ 👥 💪 ⚙️ 🔗 ⏮️:

//// tab | 🐍 3️⃣.6️⃣ & 🔛

```Python hl_lines="22"

    return item_id


@app.get("/path/param-le-ge-int/{item_id}")
def get_path_param_le_ge_int(item_id: int = Path(le=3, ge=1)):
    return item_id


@app.get("/query")
def get_query(query):
    return f"foo bar {query}"


@app.get("/query/optional")
def get_query_optional(query=None):
    if query is None:
        return "foo bar"
    return f"foo bar {query}"

    * It depends on the `query_extractor`, and assigns the value returned by it to the parameter `q`.
* It also declares an optional `last_query` cookie, as a `str`.
    * If the user didn't provide any query `q`, we use the last query used, which we saved to a cookie before.

## Use the dependency

Then we can use the dependency with:

    * Sie hängt von `query_extractor` ab und weist den von diesem zurückgegebenen Wert dem Parameter `q` zu.
* Sie deklariert außerdem ein optionales `last_query`-Cookie, ein `str`.
    * Wenn der Benutzer keine Query `q` übermittelt hat, verwenden wir die zuletzt übermittelte Query, die wir zuvor in einem Cookie gespeichert haben.

## Die Abhängigkeit verwenden