Und Sie möchten diese Exception global mit FastAPI handhaben.

Sie könnten einen benutzerdefinierten Exceptionhandler mittels `@app.exception_handler()` hinzufügen:

```Python hl_lines="5-7  13-18  24"
{!../../../docs_src/handling_errors/tutorial003.py!}
```

Wenn Sie nun `/unicorns/yolo` anfragen, `raise`d die *Pfadoperation* eine `UnicornException`.

The `security_scopes` object (of class `SecurityScopes`) also provides a `scope_str` attribute with a single string, containing those scopes separated by spaces (we are going to use it).

We create an `HTTPException` that we can re-use (`raise`) later at several points.

    Note over client,tasks: Can raise exception for dependency, handled after response is sent
    Note over client,operation: Can raise HTTPException and can change the response
    client ->> dep: Start request
    Note over dep: Run code up to yield
    opt raise
        dep -->> handler: Raise HTTPException
        handler -->> client: HTTP error response
        dep -->> dep: Raise other exception
    end

    * Pól tekstowych (`str`) z określeniem minimalnej i maksymalnej długości.
    * Liczb (`int`, `float`) z wartościami minimalnymi, maksymalnymi, itp.

* Walidacja bardziej egzotycznych typów danych, takich jak:
    * URL.
    * Email.
    * UUID.
    * ...i inne.

Cała walidacja jest obsługiwana przez ugruntowaną i solidną bibliotekę **Pydantic**.

### Bezpieczeństwo i uwierzytelnianie

    ```Python hl_lines="68-69  81"
    {!> ../../../docs_src/websockets/tutorial002.py!}
    ```

!!! info
    As this is a WebSocket it doesn't really make sense to raise an `HTTPException`, instead we raise a `WebSocketException`.

    You can use a closing code from the <a href="https://tools.ietf.org/html/rfc6455#section-7.4.1" class="external-link" target="_blank">valid codes defined in the specification</a>.

`HTTPException`, ao fundo, nada mais é do que a conjunção entre uma exceção comum do Python e informações adicionais relevantes para APIs.

E porque é uma exceção do Python, você não **retorna** (return) o `HTTPException`, você lança o (raise) no seu código.

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python hl_lines="6  11"
    {!> ../../../docs_src/dependencies/tutorial006.py!}
    ```

### Raise exceptions

These dependencies can `raise` exceptions, the same as normal dependencies:

=== "Python 3.9+"

    ```Python hl_lines="10  15"
    {!> ../../../docs_src/dependencies/tutorial006_an_py39.py!}
    ```

=== "Python 3.8+"

    length: Int,
    flags: Int,
    streamId: Int,
  ) {
    if (streamId == 0) throw IOException("PROTOCOL_ERROR: TYPE_DATA streamId == 0")

    // TODO: checkState open or half-closed (local) or raise STREAM_CLOSED
    val inFinished = flags and FLAG_END_STREAM != 0
    val gzipped = flags and FLAG_COMPRESSED != 0
    if (gzipped) {
      throw IOException("PROTOCOL_ERROR: FLAG_COMPRESSED without SETTINGS_COMPRESS_DATA")

##### Nouvelle langue non prise en charge

Si, lors de l'exécution du script du serveur en direct, vous obtenez une erreur indiquant que la langue n'est pas prise en charge, quelque chose comme :

```
 raise TemplateNotFound(template)
jinja2.exceptions.TemplateNotFound: partials/language/xx.html
```

Cela signifie que le thème ne supporte pas cette langue (dans ce cas, avec un faux code de 2 lettres de `xx`).

### 依存関係の要件

これらはリクエストの要件（ヘッダのようなもの）やその他のサブ依存関係を宣言することができます:

```Python hl_lines="6 11"
{!../../../docs_src/dependencies/tutorial006.py!}
```

### 例外の発生

これらの依存関係は通常の依存関係と同じように、例外を`raise`発生させることができます:

```Python hl_lines="8 13"
{!../../../docs_src/dependencies/tutorial006.py!}
```

### 戻り値

そして、値を返すことも返さないこともできますが、値は使われません。

つまり、すでにどこかで使っている通常の依存関係（値を返すもの）を再利用することができ、値は使われなくても依存関係は実行されます: