# Query-Parameter

Wenn Sie in ihrer Funktion Parameter deklarieren, die nicht Teil der Pfad-Parameter sind, dann werden diese automatisch als „Query“-Parameter interpretiert.

```Python hl_lines="9"
{!../../../docs_src/query_params/tutorial001.py!}
```

Query-Parameter (Deutsch: Abfrage-Parameter) sind die Schlüssel-Wert-Paare, die nach dem `?` in einer URL aufgelistet sind, getrennt durch `&`-Zeichen.

Zum Beispiel sind in der URL:

```

=== "Python 3.10+"

    ```Python hl_lines="7"
    {!> ../../../docs_src/query_params/tutorial002_py310.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="9"
    {!> ../../../docs_src/query_params/tutorial002.py!}
    ```

Bu durumda, `q` fonksiyon parametresi isteğe bağlı olacak ve varsayılan değer olarak `None` alacaktır.

## 📦 🔢

🎏 🌌, 👆 💪 📣 📦 🔢 🔢, ⚒ 👫 🔢 `None`:

=== "🐍 3️⃣.6️⃣ & 🔛"

    ```Python hl_lines="9"
    {!> ../../../docs_src/query_params/tutorial002.py!}
    ```

=== "🐍 3️⃣.1️⃣0️⃣ & 🔛"

    ```Python hl_lines="7"
    {!> ../../../docs_src/query_params/tutorial002_py310.py!}
    ```

👉 💼, 🔢 🔢 `q` 🔜 📦, & 🔜 `None` 🔢.

!!! check

# Query Parameters

When you declare other function parameters that are not part of the path parameters, they are automatically interpreted as "query" parameters.

```Python hl_lines="9"
{!../../../docs_src/query_params/tutorial001.py!}
```

The query is the set of key-value pairs that go after the `?` in a URL, separated by `&` characters.

For example, in the URL:

```
http://127.0.0.1:8000/items/?skip=0&limit=10
```

```Python hl_lines="9"
{!../../../docs_src/query_params/tutorial001.py!}
```

La partie appelée requête (ou **query**) dans une URL est l'ensemble des paires clés-valeurs placées après le `?` , séparées par des `&`.

Par exemple, dans l'URL :

```
http://127.0.0.1:8000/items/?skip=0&limit=10
```

Like in:

```
http://127.0.0.1:8000/items/?item-query=foobaritems
```

But `item-query` is not a valid Python variable name.

The closest would be `item_query`.

But you still need it to be exactly `item-query`...

Then you can declare an `alias`, and that alias is what will be used to find the parameter value:

=== "Python 3.10+"

    ```Python hl_lines="9"

## 추가 검증

`q`가 선택적이지만 값이 주어질 때마다 **값이 50 글자를 초과하지 않게** 강제하려 합니다.

### `Query` 임포트

이를 위해 먼저 `fastapi`에서 `Query`를 임포트합니다:

```Python hl_lines="3"
{!../../../docs_src/query_params_str_validations/tutorial002.py!}
```

## 기본값으로 `Query` 사용

이제 `Query`를 매개변수의 기본값으로 사용하여 `max_length` 매개변수를 50으로 설정합니다:

```Python hl_lines="9"
{!../../../docs_src/query_params_str_validations/tutorial002.py!}
```

  val encodedQuery: String?
    get() {
      if (queryNamesAndValues == null) return null // No query.
      val queryStart = url.indexOf('?') + 1
      val queryEnd = url.delimiterOffset('#', queryStart, url.length)
      return url.substring(queryStart, queryEnd)
    }

  /**
   * This URL's query, like `"abc"` for `http://host/?abc`. Most callers should prefer

---

"_We adopted the **FastAPI** library to spawn a **REST** server that can be queried to obtain **predictions**. [for Ludwig]_"

!!! info
    👀 👈 👥 🕴 📣 1️⃣ 🔗 *➡ 🛠️ 🔢*, `query_or_cookie_extractor`.

    ✋️ **FastAPI** 🔜 💭 👈 ⚫️ ✔️ ❎ `query_extractor` 🥇, 🚶‍♀️ 🏁 👈 `query_or_cookie_extractor` ⏪ 🤙 ⚫️.

```mermaid
graph TB

query_extractor(["query_extractor"])
query_or_cookie_extractor(["query_or_cookie_extractor"])

read_query["/items/"]

query_extractor --> query_or_cookie_extractor --> read_query
```

## ⚙️ 🎏 🔗 💗 🕰