### Utilizando gerenciadores de contexto em dependências com `yield` { #using-context-managers-in-dependencies-with-yield }

/// warning | Atenção

Isso é uma ideia mais ou menos "avançada".

Se você está apenas iniciando com o **FastAPI** você pode querer pular isso por enquanto.

///

### Using context managers in dependencies with `yield` { #using-context-managers-in-dependencies-with-yield }

/// warning

This is, more or less, an "advanced" idea.

If you are just starting with **FastAPI** you might want to skip it for now.

///

   * null, null, null]} regardless of the true comparison order of those three values (which might
   * not even implement {@link Comparable} at all).
   *
   * <p><b>Warning:</b> by definition, this comparator is not <i>consistent with equals</i> (as
   * defined {@linkplain Comparator here}). Avoid its use in APIs, such as {@link
   * TreeSet#TreeSet(Comparator)}, where such consistency is expected.

作用域是更精密的权限系统，遵循 OAuth2 标准，与 OpenAPI 应用（和 API 自动文档）集成。

OAuth2 也是脸书、谷歌、GitHub、微软、推特等第三方身份验证应用使用的机制。这些身份验证应用在用户登录应用时使用 OAuth2 提供指定权限。

脸书、谷歌、GitHub、微软、推特就是 OAuth2 作用域登录。

本章介绍如何在 **FastAPI** 应用中使用 OAuth2 作用域管理验证与授权。

/// warning | 警告

本章内容较难，刚接触 FastAPI 的新手可以跳过。

OAuth2 作用域不是必需的，没有它，您也可以处理身份验证与授权。

但 OAuth2 作用域与 API（通过 OpenAPI）及 API 文档集成地更好。

不管怎么说，**FastAPI** 支持在代码中使用作用域或其它安全/授权需求项。

很多情况下，OAuth2 作用域就像一把牛刀。

Exatamente como queríamos. ✔️

Isso porque o FastAPI usa esse `root_path` para criar o `server` padrão no OpenAPI com o URL fornecido pelo `root_path`.

## Servidores adicionais { #additional-servers }

/// warning | Atenção

Este é um caso de uso mais avançado. Sinta-se à vontade para pular.

///

Por padrão, o **FastAPI** criará um `server` no OpenAPI schema com o URL para o `root_path`.

									title="<la:message key="labels.development_mode_warning" />"
								><a class="nav-link active" href="${installationLink}" target="_olh"><em
										class="fa fa-exclamation-triangle text-warning"
									></a></li>
							</c:if>
							<c:choose>
								<c:when test="${!empty username && username != 'guest'}">
									<li class="nav-item">
										<div class="dropdown">

        }

        try {
            "".getBytes(DEFAULT_OEM_ENCODING);
        } catch (final UnsupportedEncodingException uee) {
            if (LogStream.level >= 2) {
                log.println("WARNING: The default OEM encoding " + DEFAULT_OEM_ENCODING
                        + " does not appear to be supported by this JRE. The default encoding will be US-ASCII.");
            }
            DEFAULT_OEM_ENCODING = "US-ASCII";

   *
   * <p>Note however that if your escaper does not escape characters in the supplementary range, you
   * should either continue to validate the correctness of any surrogate characters encountered or
   * provide a clear warning to users that your escaper does not validate its input.
   *
   * <p>See {@link com.google.common.net.PercentEscaper} for an example.
   *
   * @param csq a sequence of characters

In this scenario of "fast food burgers with your crush", as there is a lot of waiting 🕙, it makes a lot more sense to have a concurrent system ⏸🔀⏯.

This is the case for most of the web applications.

Many, many users, but your server is waiting 🕙 for their not-so-good connection to send their requests.

And then waiting 🕙 again for the responses to come back.

### Kontextmanager in Abhängigkeiten mit `yield` verwenden { #using-context-managers-in-dependencies-with-yield }

/// warning | Achtung

Dies ist mehr oder weniger eine „fortgeschrittene“ Idee.

Wenn Sie gerade erst mit **FastAPI** beginnen, möchten Sie das vielleicht vorerst überspringen.

///