# Header 参数

定义 `Header` 参数的方式与定义 `Query`、`Path`、`Cookie` 参数相同。

## 导入 `Header`

首先，导入 `Header`：

{* ../../docs_src/header_params/tutorial001_an_py310.py hl[3] *}

## 声明 `Header` 参数

然后，使用和 `Path`、`Query`、`Cookie` 一样的结构定义 header 参数。

第一个值是默认值，还可以传递所有验证参数或注释参数：

{* ../../docs_src/header_params/tutorial001_an_py310.py hl[9] *}

/// note | 技术细节

`Header` 是 `Path`、`Query`、`Cookie` 的**兄弟类**，都继承自共用的 `Param` 类。

     * @param response the HTTP servlet response
     * @param path     the request path after removing the prefix
     */
    protected void processRequest(final HttpServletRequest request, final HttpServletResponse response, final String path) {
        if ("/_plugin".equals(path) || path.startsWith("/_plugin/")) {
            processPluginRequest(request, response, path.replaceFirst("^/_plugin", StringUtil.EMPTY));
            return;

* include: включать (add `в себя` if it's appropriate, or use `содержать` as an alternative)
* virtual environment: виртуальное окружение
* framework: фреймворк
* path paremeter: path-параметр
* path (as in URL path): путь
* form (as in HTML form): форма
* media type: тип содержимого (or `медиа-тип`)
* request: HTTP-запрос
* response: HTTP-ответ
* type hints: аннотации типов

        Path mavenHome = fs.getPath("/maven");
        Files.createDirectories(mavenHome);
        Path mavenConf = mavenHome.resolve("conf");
        Files.createDirectories(mavenConf);
        Path mavenUserProps = mavenConf.resolve("maven.properties");
        Files.writeString(mavenUserProps, "${includes} = ?\"/user/ma ven.properties\",  ?/foo/bar\n");
        Path userDirectory = fs.getPath("/user");

## Dokümantasyon Özeti ve Açıklaması - OpenAPI

	Path     string                        `yaml:"path" json:"path"`
	Creds    BatchJobReplicateCredentials  `yaml:"credentials" json:"credentials"`
}

// ValidPath returns true if path is valid
func (t BatchJobReplicateTarget) ValidPath() bool {
	return t.Path == "on" || t.Path == "off" || t.Path == "auto" || t.Path == ""
}

from typing import Annotated

from fastapi import FastAPI, Path

app = FastAPI()


@app.get("/items/{item_id}")
async def read_items(
    q: str, item_id: Annotated[int, Path(title="The ID of the item to get")]
):
    results = {"item_id": item_id}
    if q:
        results.update({"q": q})

from typing import Annotated

from fastapi import FastAPI, Path

app = FastAPI()


@app.get("/items/{item_id}")
async def read_items(
    item_id: Annotated[int, Path(title="The ID of the item to get")], q: str
):
    results = {"item_id": item_id}
    if q:
        results.update({"q": q})

    have prod supersource, even if they have none. GWT is happy to ignore us
    when we specify a nonexistent path.

    (I hope that this workaround does not cause its own problems in the future.)
-->
<super-source path="super"/>

<inherits name="com.google.common.annotations.Annotations" />
<inherits name="com.google.common.base.Base" />

        assertEquals("gcs", url.getProtocol());
    }

    /**
     * Test URL parsing with bucket and object path.
     */
    public void test_urlParsing_bucketAndObject() throws Exception {
        URL url = new URL("gcs://mybucket/path/to/object.txt");
        Handler handler = new Handler();
        URLConnection conn = handler.openConnection(url);