A simplicidade do sistema de injeção de dependência do **FastAPI** faz ele compatível com:

* todos os bancos de dados relacionais
* bancos de dados NoSQL
* pacotes externos
* APIs externas
* sistemas de autenticação e autorização
* istemas de monitoramento de uso para APIs
* sistemas de injeção de dados de resposta
* etc.

## Simples e Poderoso { #simple-and-powerful }

**FastAPI** 提供了以下内容：

### 建立在開放標準的基礎上

* 使用 <a href="https://github.com/OAI/OpenAPI-Specification" class="external-link" target="_blank"><strong>OpenAPI</strong></a> 來建立 API，包含<abbr title="path，也被叫做: endpoints, routes">路徑</abbr><abbr title="也叫做 HTTP 方法，例如 POST, GET, PUT, DELETE">操作</abbr>、參數、請求內文、安全性等聲明。
* 使用 <a href="https://json-schema.org/" class="external-link" target="_blank"><strong>JSON Schema</strong></a>（因為 OpenAPI 本身就是基於 JSON Schema）自動生成資料模型文件。

## 本地测试 Traefik

您可以轻易地在本地使用 <a href="https://docs.traefik.io/" class="external-link" target="_blank">Traefik</a> 运行移除路径前缀的试验。

<a href="https://github.com/containous/traefik/releases" class="external-link" target="_blank">下载 Traefik</a>，这是一个二进制文件，需要解压文件，并在 Terminal 中直接运行。

然后创建包含如下内容的 `traefik.toml` 文件：

```TOML hl_lines="3"
[entryPoints]

* 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：

* <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/X-Forwarded-Proto" class="external-link" target="_blank">X-Forwarded-Proto</a>
* <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Reference/Headers/X-Forwarded-Host" class="external-link" target="_blank">X-Forwarded-Host</a>

///

Unauthorized`, and return a sensible `WWW-Authenticate` header in the response, following the HTTP specifications, <a href="https://datatracker.ietf.org/doc/html/rfc7235#section-3.1" class="external-link" target="_blank">RFC 7235</a>, <a href="https://datatracker.ietf.org/doc/html/rfc9110#name-401-unauthorized" class="external-link" target="_blank">RFC 9110</a>.

But if for some reason your clients depend on the old behavior, you can revert to it by overriding the method `make_not_authenticated_error`...

E o resto será manipulado pelo **FastAPI**.

Se você rodar a aplicação e ir até <a href="http://localhost:8000/v1/" class="external-link" target="_blank">http://localhost:8000/v1/</a>, você verá o retorno do Flask:

```txt
Hello, World from Flask!
```

E se você for até <a href="http://localhost:8000/v2" class="external-link" target="_blank">http://localhost:8000/v2</a>, você verá o retorno do FastAPI:

```JSON
{

* <a href="https://github.com/florimondmanca/msgpack-asgi" class="external-link" target="_blank">MessagePack</a>

* <a href="https://github.com/florimondmanca/msgpack-asgi" class="external-link" target="_blank">MessagePack</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 и со стандартной библиотекой Python <a href="https://docs.python.org/3/library/asyncio-task.html" class="external-link" target="_blank">asyncio</a>, и с <a href="https://trio.readthedocs.io/en/stable/" class="external-link" target="_blank">Trio</a>.