# 路径参数 { #path-parameters }

你可以使用与 Python 字符串格式化相同的语法声明路径“参数”或“变量”：

{* ../../docs_src/path_params/tutorial001_py310.py hl[6:7] *}

路径参数 `item_id` 的值会作为参数 `item_id` 传递给你的函数。

运行示例并访问 [http://127.0.0.1:8000/items/foo](http://127.0.0.1:8000/items/foo)，可获得如下响应：

```JSON
{"item_id":"foo"}
```

## 声明路径参数的类型 { #path-parameters-with-types }

使用 Python 标准类型注解，声明路径操作函数中路径参数的类型：

      When doing so, still annotate nullable parameters and the return type as `@Nullable`.
  * Do not use `@Contract` for public APIs.
  * For polynull public APIs, the solution has to be decided on a case-by-case basis.

Do not remove `null` checks on public API boundaries, even if the annotations (or rather lack of them) suggest this.
Not all client code is compiled with NullAway.

import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Tester to ensure forwarding wrapper works by delegating calls to the corresponding method with
 * the same parameters forwarded and return value forwarded back or exception propagated as is.
 *
 * <p>For example:
 *
 * {@snippet :
 * new ForwardingWrapperTester().testForwarding(Foo.class, new Function<Foo, Foo>() {

///

Il contient toutes les informations sur le chemin d’accès et est utilisé pour générer la documentation automatique.

Il inclut les `tags`, `parameters`, `requestBody`, `responses`, etc.

Ce schéma OpenAPI spécifique à un chemin d’accès est normalement généré automatiquement par **FastAPI**, mais vous pouvez également l’étendre.

/// tip | Astuce

# 본문 - 다중 매개변수 { #body-multiple-parameters }

이제 `Path`와 `Query`를 어떻게 사용하는지 확인했으니, 요청 본문 선언에 대한 더 고급 사용법을 살펴보겠습니다.

## `Path`, `Query` 및 본문 매개변수 혼합 { #mix-path-query-and-body-parameters }

먼저, 물론 `Path`, `Query` 및 요청 본문 매개변수 선언을 자유롭게 혼합해서 사용할 수 있고, **FastAPI**는 어떤 동작을 할지 압니다.

또한 기본 값을 `None`으로 설정해 본문 매개변수를 선택사항으로 선언할 수 있습니다:

{* ../../docs_src/body_multiple_params/tutorial001_an_py310.py hl[18:20] *}

/// note | 참고

# 请求体 - 多个参数 { #body-multiple-parameters }

既然我们已经知道了如何使用 `Path` 和 `Query`，下面让我们来了解一下请求体声明的更高级用法。

## 混合使用 `Path`、`Query` 和请求体参数 { #mix-path-query-and-body-parameters }

首先，毫无疑问地，你可以随意地混合使用 `Path`、`Query` 和请求体参数声明，**FastAPI** 会知道该如何处理。

你还可以通过将默认值设置为 `None` 来将请求体参数声明为可选参数：

{* ../../docs_src/body_multiple_params/tutorial001_an_py310.py hl[18:20] *}

/// note | 注意

请注意，在这种情况下，将从请求体获取的 `item` 是可选的。因为它的默认值为 `None`。

///

		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrSSEEncryptedObject: {
		Code:           "InvalidRequest",
		Description:    "The object was stored using a form of Server Side Encryption. The correct parameters must be provided to retrieve the object.",
		HTTPStatusCode: http.StatusBadRequest,
	},

* to reach users: донести до пользователей (or `привлечь внимание пользователей` in the promotion context)
* body (meaning HTTP request body): тело запроса
* body (meaning HTTP response body): тело ответа
* body parameter : body-параметр (or `параметр тела запроса`)
* validate: валидировать (or `выполнить валидацию`)
* requirements (meaning dependencies): зависимости

Podría ser llamada como:

```Python
oauth2_scheme(some, parameters)
```

Así que, puede usarse con `Depends`.

### Úsalo { #use-it }

Ahora puedes pasar ese `oauth2_scheme` en una dependencia con `Depends`.

{* ../../docs_src/security/tutorial001_an_py310.py hl[12] *}

Esta dependencia proporcionará un `str` que se asigna al parámetro `token` de la *path operation function*.

Ela pode ser chamada como:

```Python
oauth2_scheme(some, parameters)
```

Então, pode ser usada com `Depends`.

### Use-o { #use-it }

Agora você pode passar esse `oauth2_scheme` em uma dependência com `Depends`.

{* ../../docs_src/security/tutorial001_an_py310.py hl[12] *}

Essa dependência fornecerá uma `str` que é atribuída ao parâmetro `token` da função de operação de rota.