Sie können benutzerdefinierte <abbr title="Ausnahmebehandler: Funktion, die sich um die Bearbeitung einer Exception kümmert">Exceptionhandler</abbr> mit <a href="https://www.starlette.dev/exceptions/" class="external-link" target="_blank">den gleichen Exception-Werkzeugen von Starlette</a> hinzufügen.

Sie können das Attribut `model_config` verwenden, das ein <abbr title="Dictionary – Zuordnungstabelle: In anderen Sprachen auch Hash, Map, Objekt, Assoziatives Array genannt">`dict`</abbr> akzeptiert, wie beschrieben in <a href="https://docs.pydantic.dev/latest/api/config/" class="external-link" target="_blank">Pydantic-Dokumentation: Configuration</a>.

installieren.

Das liegt daran, dass **OAuth2** „Formulardaten“ zum Senden von `username` und `password` verwendet.

///

Führen Sie das Beispiel aus mit:

<div class="termy">

```console
$ fastapi dev main.py

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

## Es testen { #check-it }

<img src="/img/tutorial/path-params/image02.png">

同样，还有很多兼容工具，包括多种语言的代码生成工具。

## Pydantic

FastAPI 充分地利用了 <a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic</a> 的优势，用它在后台校验数据。众所周知，Pydantic 擅长的就是数据校验。

同样，`str`、`float`、`bool` 以及很多复合数据类型都可以使用类型声明。

下一章介绍详细内容。

## 顺序很重要

有时，*路径操作*中的路径是写死的。

## Pydantic { #pydantic }

Toda a validação de dados é realizada nos bastidores pelo <a href="https://docs.pydantic.dev/" class="external-link" target="_blank">Pydantic</a>, então você recebe todos os benefícios disso. E você sabe que está em boas mãos.

apiVersion: v1 appVersion: RELEASE.2022-01-08T03-11-54Z description: Multi-Cloud Object Storage home: https://min.io icon: https://min.io/resources/img/logo/MINIO_wordmark.png keywords: - minio - storage - object-storage - s3 - cluster maintainers: - email: dev@minio.io name: MinIO, Inc name: minio sources: - https://github.com/minio/minio version: 3.4.6 minio/values.yaml ## Provide a name in place of minio for `app:` labels ## nameOverride: "" ## Provide a name to substitute for the full names of resources...

apiVersion: v1 appVersion: RELEASE.2022-01-28T02-28-16Z description: Multi-Cloud Object Storage home: https://min.io icon: https://min.io/resources/img/logo/MINIO_wordmark.png keywords: - minio - storage - object-storage - s3 - cluster maintainers: - email: dev@minio.io name: MinIO, Inc name: minio sources: - https://github.com/minio/minio version: 3.4.8 minio/values.yaml ## Provide a name in place of minio for `app:` labels ## nameOverride: "" ## Provide a name to substitute for the full names of resources...

apiVersion: v1 appVersion: RELEASE.2022-02-07T08-17-33Z description: Multi-Cloud Object Storage home: https://min.io icon: https://min.io/resources/img/logo/MINIO_wordmark.png keywords: - minio - storage - object-storage - s3 - cluster maintainers: - email: dev@minio.io name: MinIO, Inc name: minio sources: - https://github.com/minio/minio version: 3.5.2 minio/values.yaml ## Provide a name in place of minio for `app:` labels ## nameOverride: "" ## Provide a name to substitute for the full names of resources...

apiVersion: v1 appVersion: RELEASE.2021-10-06T23-36-31Z description: Multi-Cloud Object Storage home: https://min.io icon: https://min.io/resources/img/logo/MINIO_wordmark.png keywords: - minio - storage - object-storage - s3 - cluster maintainers: - email: dev@minio.io name: MinIO, Inc name: minio sources: - https://github.com/minio/minio version: 3.1.8 minio/values.yaml ## Provide a name in place of minio for `app:` labels ## nameOverride: "" ## Provide a name to substitute for the full names of resources...

				ModTime:  time.Unix(1314603082, 0),
			}, nil},
			testWrite{"", 0, nil},

			testClose{nil},
		},
	}, {
		// The truncated test file was produced using these commands:
		//   dd if=/dev/zero bs=1048576 count=16384 > /tmp/16gig.txt
		//   tar -b 1 -c -f- /tmp/16gig.txt | dd bs=512 count=8 > writer-big.tar
		file: "testdata/writer-big.tar",
		tests: []testFnc{
			testHeader{Header{
				Typeflag: TypeReg,