E então outra tarefa em segundo plano gerada na *função de operação de rota* escreverá uma mensagem usando o parâmetro de path `email`.

## Detalhes técnicos { #technical-details }

A classe `BackgroundTasks` vem diretamente de <a href="https://www.starlette.dev/background/" class="external-link" target="_blank">`starlette.background`</a>.

///

////

//// tab | Pydantic v1

{* ../../docs_src/settings/app03_an_py39/config_pv1.py hl[9:10] *}

/// tip | Совет

## Détails techniques

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

## 容器镜像

Docker 一直是创建和管理**容器镜像**和**容器**的主要工具之一。

还有一个公共 <a href="https://hub.docker.com/" class="external-link" target="_blank">Docker Hub</a> ，其中包含预制的 **官方容器镜像**, 适用于许多工具、环境、数据库和应用程序。

例如，有一个官方的 <a href="https://hub.docker.com/_/python" class="external-link" target="_blank">Python 镜像</a>。

还有许多其他镜像用于不同的需要（例如数据库），例如：


* <a href="https://hub.docker.com/_/postgres" class="external-link" target="_blank">PostgreSQL</a>

`TestClient` основан на <a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a>, и, к счастью, мы можем использовать его (`HTTPX`) напрямую для тестирования API.

## Пример { #example }

 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class forwards calls to <i>only some</i> {@code
 * default} methods. Specifically, it forwards calls only for methods that existed <a
 * href="https://docs.oracle.com/javase/7/docs/api/java/util/ListIterator.html">before {@code

 * override one or more methods to modify the behavior of the backing map as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class forwards calls to <i>only some</i> {@code
 * default} methods. Specifically, it forwards calls only for methods that existed <a
 * href="https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/ConcurrentMap.html">before

# FastAPI Cloud { #fastapi-cloud }

Você pode implantar sua aplicação FastAPI no <a href="https://fastapicloud.com" class="external-link" target="_blank">FastAPI Cloud</a> com um **único comando**; entre na lista de espera, caso ainda não tenha feito isso. 🚀

## Login { #login }

Certifique-se de que você já tem uma conta no **FastAPI Cloud** (nós convidamos você a partir da lista de espera 😉).

Depois, faça login:

<div class="termy">

```console

除此之外，还有其他一些可选的 ASGI 服务器，例如：

* <a href="https://www.uvicorn.dev/" class="external-link" target="_blank">Uvicorn</a>：高性能 ASGI 服务器。
* <a href="https://hypercorn.readthedocs.io/" class="external-link" target="_blank">Hypercorn</a>：与 HTTP/2 和 Trio 等兼容的 ASGI 服务器。
* <a href="https://github.com/django/daphne" class="external-link" target="_blank">Daphne</a>：为 Django Channels 构建的 ASGI 服务器。

`TestClient` 在内部通过一些“魔法”操作，使得您可以在普通的 `def` 测试函数中调用异步的 FastAPI 应用程序，并使用标准的 pytest。但当我们在异步函数中使用它时，这种“魔法”就不再生效了。由于测试以异步方式运行，我们无法在测试函数中继续使用 `TestClient`。

`TestClient` 是基于 <a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a> 的。幸运的是，我们可以直接使用它来测试API。

## 示例