But if you have custom headers that you want a client in a browser to be able to see, you need to add them to your CORS configurations ([CORS (Cross-Origin Resource Sharing)](cors.md){.internal-link target=_blank}) using the parameter `expose_headers` documented in <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">Starlette's CORS docs</a>.

class="external-link" target="_blank">Verwenden Sie dafür das Präfix 'X-'</a>.

    Wenn Sie jedoch benutzerdefinierte Header haben, die ein Client in einem Browser sehen soll, müssen Sie sie zu Ihrer CORS-Konfigurationen ([CORS (Cross-Origin Resource Sharing)](cors.md){.internal-link target=_blank}) hinzufügen, indem Sie den Parameter `expose_headers` verwenden, der in der <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">Starlette-CORS-Dokumentation</a>...

By default, **FastAPI** will create a `server` in the OpenAPI schema with the URL for the `root_path`.

But you can also provide other alternative `servers`, for example if you want *the same* docs UI to interact with a staging and production environments.

If you pass a custom list of `servers` and there's a `root_path` (because your API lives behind a proxy), **FastAPI** will insert a "server" with this `root_path` at the beginning of the list.

* Grundlegende Startmodelle für Benutzer (ändern und entfernen Sie nach Bedarf).
* **Alembic**-Migrationen.
* **CORS** (Cross Origin Resource Sharing).
* **Celery**-Worker, welche Modelle und Code aus dem Rest des Backends selektiv importieren und verwenden können.

    그러나 만약 클라이언트의 브라우저에서 볼 수 있는 사용자 정의 헤더를 가지고 있다면, 그것들을 CORS 설정([CORS (Cross-Origin Resource Sharing)](cors.md){.internal-link target=_blank})에 <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">Starlette CORS 문서</a>에 명시된 `expose_headers` 매개변수를 이용하여 헤더들을 추가하여야합니다.

!!! note "기술적 세부사항"

* 📝 Add hyperlink to `docs/en/docs/tutorial/static-files.md`. PR [#10243](https://github.com/tiangolo/fastapi/pull/10243) by [@hungtsetse](https://github.com/hungtsetse).
* 📝 Add External Link: Instrument a FastAPI service adding tracing with OpenTelemetry and send/show traces in Grafana Tempo. PR [#9440](https://github.com/tiangolo/fastapi/pull/9440) by [@softwarebloat](https://github.com/softwarebloat).

werden können.

Wenn Sie jedoch benutzerdefinierte Header haben, die ein Client in einem Browser sehen können soll, müssen Sie diese zu Ihren CORS-Konfigurationen hinzufügen (weitere Informationen finden Sie unter [CORS (Cross-Origin Resource Sharing)](../tutorial/cors.md){.internal-link target=_blank}), unter Verwendung des Parameters `expose_headers`, dokumentiert in <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">Starlettes CORS-Dokumentation</a>....

target="_blank">usando el prefijo 'X-'</a>.

Si tienes headers personalizados y deseas que un cliente pueda verlos en el navegador, es necesario que los añadas a tus configuraciones de CORS (puedes leer más en [CORS (Cross-Origin Resource Sharing)](../tutorial/cors.md){.internal-link target=_blank}), usando el parámetro `expose_headers` documentado en <a href="https://www.starlette.io/middleware/#corsmiddleware" class="external-link" target="_blank">Starlette's CORS docs</a>....

As code duplication increments the chances of bugs, security issues, code desynchronization issues (when you update in one place but not in the others), etc.

And these models are all sharing a lot of the data and duplicating attribute names and types.

We could do better.

# CORS (Cross-Origin Resource Sharing)

<a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS" class="external-link" target="_blank">Понятие CORS или "Cross-Origin Resource Sharing"</a> относится к ситуациям, при которых запущенный в браузере фронтенд содержит JavaScript-код, который взаимодействует с бэкендом, находящимся на другом "источнике" ("origin").

## Источник