**FastAPI** will **extract** the data for **each field** from the **headers** in the request and give you the Pydantic model you defined.

## Check the Docs { #check-the-docs }

You can see the required headers in the docs UI at `/docs`:

<div class="screenshot">
<img src="/img/tutorial/header-param-models/image01.png">
</div>

## Forbid Extra Headers { #forbid-extra-headers }

# Clients generieren

Da **FastAPI** auf der OpenAPI-Spezifikation basiert, erhalten Sie automatische Kompatibilität mit vielen Tools, einschließlich der automatischen API-Dokumentation (bereitgestellt von Swagger UI).

Ein besonderer Vorteil, der nicht unbedingt offensichtlich ist, besteht darin, dass Sie für Ihre API **Clients generieren** können (manchmal auch <abbr title="Software Development Kits">**SDKs**</abbr> genannt), für viele verschiedene **Programmiersprachen**.

That way, the sub-application will know to use that path prefix for the docs UI.

And the sub-application could also have its own mounted sub-applications and everything would work correctly, because FastAPI handles all these `root_path`s automatically.

Aquí declaramos la configuración `openapi_url` con el mismo valor predeterminado de `"/openapi.json"`.

Y luego la usamos al crear la app de `FastAPI`.

Entonces podrías desactivar OpenAPI (incluyendo las UI de documentación) configurando la variable de entorno `OPENAPI_URL` a una string vacía, así:

<div class="termy">

```console
$ OPENAPI_URL= uvicorn main:app

{* ../../docs_src/openapi_webhooks/tutorial001.py hl[9:13,36:53] *}

The webhooks that you define will end up in the **OpenAPI** schema and the automatic **docs UI**.

/// info

The `app.webhooks` object is actually just an `APIRouter`, the same type you would use when structuring your app with multiple files.

///

# Generate Clients

Como o **FastAPI** é baseado na especificação **OpenAPI**, você obtém compatibilidade automática com muitas ferramentas, incluindo a documentação automática da API (fornecida pelo Swagger UI).

Uma vantagem particular que nem sempre é óbvia é que você pode **gerar clientes** (às vezes chamados de <abbr title="Software Development Kits">**SDKs**</abbr>) para a sua API, para muitas **linguagens de programação** diferentes.

## Geradores de Clientes OpenAPI

FastAPI 0.99.0 이전 버전에서 (0.99.0 이상 버전은 새로운 OpenAPI 3.1.0을 사용합니다), `example` 혹은 `examples`를 다른 유틸리티(`Query()`, `Body()` 등)와 함께 사용했을 때, 저러한 예시는 데이터를 설명하는 JSON 스키마에 추가되지 않으며 (심지어 OpenAPI의 자체 JSON 스키마에도 포함되지 않습니다), OpenAPI의 *경로 작동* 선언에 직접적으로 추가됩니다 (JSON 스키마를 사용하는 OpenAPI 부분 외에도).

**FastAPI** 애플리케이션을 만들 때, `webhooks` 속성을 사용하여 *웹훅*을 정의할 수 있습니다. 이는 `@app.webhooks.post()`와 같은 방식으로 *경로(path) 작업*을 정의하는 것과 비슷합니다.

{* ../../docs_src/openapi_webhooks/tutorial001.py hl[9:13,36:53] *}

이렇게 정의한 웹훅은 **OpenAPI** 스키마와 자동 **문서화 UI**에 표시됩니다.

/// info

`app.webhooks` 객체는 사실 `APIRouter`일 뿐이며, 여러 파일로 앱을 구성할 때 사용하는 것과 동일한 타입입니다.

///

Also, before that, in previous versions, the `request` object was passed as part of the key-value pairs in the context for Jinja2.

///

/// tip

By declaring `response_class=HTMLResponse` the docs UI will be able to know that the response will be HTML.

///

/// note | Technical Details

You could also use `from starlette.templating import Jinja2Templates`.

به این ترتیب، زیر برنامه می داند که از آن پیشوند مسیر برای رابط کاربری اسناد (docs UI) استفاده کند.

و زیر برنامه ها نیز می تواند زیر برنامه های متصل شده خود را داشته باشد و همه چیز به درستی کار کند، زیرا FastAPI تمام این مسیرهای `root_path` را به طور خودکار مدیریت می کند.