Aber falls Sie es für ein fortgeschrittenes Szenario benötigen, können Sie benutzerdefinierte Header hinzufügen:

{* ../../docs_src/handling_errors/tutorial002_py39.py hl[14] *}

## Benutzerdefinierte Exceptionhandler installieren { #install-custom-exception-handlers }

{* ../../docs_src/security/tutorial001_an_py39.py *}

## 运行

/// info | 说明

先安装 <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>。

安装命令： `pip install python-multipart`。

这是因为 **OAuth2** 使用**表单数据**发送 `username` 与 `password`。

///

用下面的命令运行该示例：

<div class="termy">

```console
$ uvicorn main:app --reload

* 100% <abbr title="Python type annotations, with this your editor and external tools can give you better support">typeları belirtilmiş</abbr> codebase.
* FastAPI ile yapılan bir çok proje insanlar tarafından kullanılıyor.

## Starlette özellikleri

maven-plugin-api\target maven-plugin-api-2.0 maven-release-plugin https://svn.apache.org/repos/asf/maven/components/tags maven-clean-plugin 2.0-rc2-SNAPSHOT maven-compiler-plugin 2.0-beta-2-SNAPSHOT maven-deploy-plugin 2.0-beta-1 true true maven-install-plugin 2.0-beta-2-SNAPSHOT maven-jar-plugin 2.0-rc2-SNAPSHOT maven-javadoc-plugin 2.0-beta-2-SNAPSHOT attach-javadocs jar true maven-resources-plugin 2.0-beta-2 maven-source-plugin 2.0-rc1 attach-sources jar true maven-surefire-plugin 2.0-beta-2-SNAPSHOT...

Antes do FastAPI 0.106.0, lançar exceções após o `yield` não era possível, o código de saída em dependências com `yield` era executado depois que a resposta era enviada, então [Tratadores de Exceções](../tutorial/handling-errors.md#install-custom-exception-handlers){.internal-link target=_blank} já teriam sido executados.

    `NullPointerException: bio == null`.


## Version 4.9.0

_2020-09-11_

**With this release, `okhttp-tls` no longer depends on Bouncy Castle and doesn't install the
Bouncy Castle security provider.** If you still need it, you can do it yourself:

```
Security.addProvider(BouncyCastleProvider())
```

You will also need to configure this dependency:

```

errors.failed_to_print_thread_dump=Failed to print a thread dump.
errors.file_is_not_supported={0} is not supported.
errors.plugin_file_is_not_found={0} is not found.
errors.failed_to_install_plugin=Failed to install {0}.
errors.failed_to_find_plugins=Could not find available plugins.
errors.failed_to_process_sso_request=Failed to process a request: {0}

errors.property_required={0} is required.

errors.failed_to_print_thread_dump=Failed to print a thread dump.
errors.file_is_not_supported={0} is not supported.
errors.plugin_file_is_not_found={0} is not found.
errors.failed_to_install_plugin=Failed to install {0}.
errors.failed_to_find_plugins=Could not find available plugins.
errors.failed_to_process_sso_request=Failed to process a request: {0}

errors.property_required={0} is required.

Vor FastAPI 0.106.0 war das Werfen von Exceptions nach `yield` nicht möglich, der Exit-Code in Abhängigkeiten mit `yield` wurde ausgeführt, nachdem die Response gesendet wurde, sodass [Exceptionhandler](../tutorial/handling-errors.md#install-custom-exception-handlers){.internal-link target=_blank} bereits ausgeführt worden wären.

* <a href="https://github.com/esnme/ultrajson" target="_blank"><code>ujson</code></a> - Obligatoire si vous souhaitez utiliser `UJSONResponse`.

Vous pouvez tout installer avec `pip install fastapi[all]`.

## Licence