## Détails techniques

La classe `BackgroundTasks` provient directement de <a href="https://www.starlette.io/background/" class="external-link" target="_blank">`starlette.background`</a>.

{!../../docs_src/middleware/tutorial001.py!}
```

/// tip | "Tipp"

Beachten Sie, dass benutzerdefinierte proprietäre Header hinzugefügt werden können. <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers" class="external-link" target="_blank">Verwenden Sie dafür das Präfix 'X-'</a>.

* Check the currently <a href="https://github.com/fastapi/fastapi/pulls" class="external-link" target="_blank">existing pull requests</a> for your language. You can filter the pull requests by the ones with the label for your language. For example, for Spanish, the label is <a href="https://github.com/fastapi/fastapi/pulls?q=is%3Aopen+sort%3Aupdated-desc+label%3Alang-es+label%3Aawaiting-review" class="external-link" target="_blank">`lang-es`</a>.

Starlette (и **FastAPI**) основаны на <a href="https://anyio.readthedocs.io/en/stable/" class="external-link" target="_blank">AnyIO</a>, что делает их совместимыми как со стандартной библиотекой <a href="https://docs.python.org/3/library/asyncio-task.html" class="external-link" target="_blank">asyncio</a> в Python, так и с <a href="https://trio.readthedocs.io/en/stable/" class="external-link" target="_blank">Trio</a>.<!--http://new.gramota.ru/spravka/buro/search-answer?s=285295-->

## Testing locally with Traefik

You can easily run the experiment locally with a stripped path prefix using <a href="https://docs.traefik.io/" class="external-link" target="_blank">Traefik</a>.

<a href="https://github.com/containous/traefik/releases" class="external-link" target="_blank">Download Traefik</a>, it's a single binary, you can extract the compressed file and run it directly from the terminal.

```

</div>

/// tip

You can read more about it at <a href="https://12factor.net/config" class="external-link" target="_blank">The Twelve-Factor App: Config</a>.

///

## Types and Validation

* <a href="https://cdn.jsdelivr.net/npm/swagger-ui-dist@5/swagger-ui.css" class="external-link" target="_blank">`swagger-ui.css`</a>

Und **ReDoc** verwendet diese Datei:

* <a href="https://cdn.jsdelivr.net/npm/redoc@next/bundles/redoc.standalone.js" class="external-link" target="_blank">`redoc.standalone.js`</a>

* 这种方式更适于处理图像、视频、二进制文件等大型文件，好处是不会占用所有内存；
* 可获取上传文件的元数据；
* 自带 <a href="https://docs.python.org/zh-cn/3/glossary.html#term-file-like-object" class="external-link" target="_blank">file-like</a> `async` 接口；
* 暴露的 Python <a href="https://docs.python.org/zh-cn/3/library/tempfile.html#tempfile.SpooledTemporaryFile" class="external-link" target="_blank">`SpooledTemporaryFile`</a> 对象，可直接传递给其他预期「file-like」对象的库。

### `UploadFile`

`UploadFile` 的属性如下：

Thanks to <a href="https://www.starlette.io/testclient/" class="external-link" target="_blank">Starlette</a>, testing **FastAPI** applications is easy and enjoyable.

It is based on <a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a>, which in turn is designed based on Requests, so it's very familiar and intuitive.

With it, you can use <a href="https://docs.pytest.org/" class="external-link" target="_blank">pytest</a> directly with **FastAPI**.

This is normally the best way to contribute to the project.

## External Contributions

External contributions are very welcome and appreciated, including answering questions, submitting PRs, etc. 🙇‍♂️