Para este exemplo simples, seremos completamente inseguros e retornaremos o mesmo `username` do token.

/// tip | Dica

No próximo capítulo, você verá uma implementação realmente segura, com hash de senha e tokens <abbr title="JSON Web Tokens">JWT</abbr>.

Mas, por enquanto, vamos nos concentrar nos detalhes específicos de que precisamos.

///

{* ../../docs_src/security/tutorial003_an_py310.py hl[87] *}

/// tip | Dica

# Python Veri Tiplerine Giriş

Python isteğe bağlı olarak "tip belirteçlerini" destekler.

 **"Tip belirteçleri"** bir değişkenin <abbr title="örneğin: str, int, float, bool">tipinin</abbr> belirtilmesine olanak sağlayan özel bir sözdizimidir.

Değişkenlerin tiplerini belirterek editör ve araçlardan daha fazla destek alabilirsiniz.

## Добавление ASGI middleware { #adding-asgi-middlewares }

Так как **FastAPI** основан на Starlette и реализует спецификацию <abbr title="Asynchronous Server Gateway Interface – Асинхронный шлюзовой интерфейс сервера">ASGI</abbr>, вы можете использовать любое ASGI middleware.

Python has support for optional "type hints" (also called "type annotations").

These **"type hints"** or annotations are a special syntax that allow declaring the <abbr title="for example: str, int, float, bool">type</abbr> of a variable.

By declaring types for your variables, editors and tools can give you better support.

And it will save the returned value in a <abbr title="A utility/system to store computed/generated values, to reuse them instead of computing them again.">"cache"</abbr> and pass it to all the "dependants" that need it in that specific request, instead of calling the dependency multiple times for the same request.

Ao definir `--proxy-headers`, agora o FastAPI conseguirá redirecionar para o local correto. 😎

```
https://mysuperapp.com/items/
```

/// tip | Dica

Se você quiser saber mais sobre HTTPS, confira o tutorial [Sobre HTTPS](../deployment/https.md){.internal-link target=_blank}.

///

### Como funcionam os headers encaminhados pelo proxy { #how-proxy-forwarded-headers-work }

将会校验数据，在数据无效时展示清晰的错误信息，并在 OpenAPI 模式的*路径操作*中记录该参​​数。

## 添加更多校验

你还可以添加 `min_length` 参数：

{* ../../docs_src/query_params_str_validations/tutorial003.py hl[10] *}

## 添加正则表达式

你可以定义一个参数值必须匹配的<abbr title="正则表达式或正则是定义字符串搜索模式的字符序列。">正则表达式</abbr>：

{* ../../docs_src/query_params_str_validations/tutorial004.py hl[11] *}

这个指定的正则表达式通过以下规则检查接收到的参数值：

* `^`：以该符号之后的字符开头，符号之前没有字符。
* `fixedquery`: 值精确地等于 `fixedquery`。

By default, those files are served from a <abbr title="Content Delivery Network: A service, normally composed of several servers, that provides static files, like JavaScript and CSS. It's commonly used to serve those files from the server closer to the client, improving performance.">CDN</abbr>.

But it's possible to customize it, you can set a specific CDN, or serve the files yourself.

It was created to generate the HTML in the backend, not to create APIs used by a modern frontend (like React, Vue.js and Angular) or by other systems (like <abbr title="Internet of Things">IoT</abbr> devices) communicating with it.

### <a href="https://www.django-rest-framework.org/" class="external-link" target="_blank">Django REST Framework</a> { #django-rest-framework }

Más adelante puedes leer sobre otros middlewares en la [Guía del Usuario Avanzado: Middleware Avanzado](../advanced/middleware.md){.internal-link target=_blank}.