description: str | None = None
    price: float | None = None
    tax: float = 10.5
    tags: list[str] = []


items = {
    "foo": {"name": "Foo", "price": 50.2},
    "bar": {"name": "Bar", "description": "The bartenders", "price": 62, "tax": 20.2},
    "baz": {"name": "Baz", "description": None, "price": 50.2, "tax": 10.5, "tags": []},
}


@app.get("/items/{item_id}", response_model=Item)

from fastapi import APIRouter, Depends, HTTPException

from ..dependencies import get_token_header

router = APIRouter(
    prefix="/items",
    tags=["items"],
    dependencies=[Depends(get_token_header)],
    responses={404: {"description": "Not found"}},
)


fake_items_db = {"plumbus": {"name": "Plumbus"}, "gun": {"name": "Portal Gun"}}


@router.get("/")
async def read_items():
    return fake_items_db

/// note | 技术细节

也可以使用 `from starlette import status` 导入状态码。

**FastAPI** 的`fastapi.status` 和 `starlette.status` 一样，只是快捷方式。实际上，`fastapi.status` 直接继承自 Starlette。

///

## `tags` 参数

`tags` 参数的值是由 `str` 组成的 `list` （一般只有一个 `str` ），`tags` 用于为*路径操作*添加标签：

{* ../../docs_src/path_operation_configuration/tutorial002.py hl[17,22,27] *}

OpenAPI 概图会自动添加标签，供 API 文档接口使用：

        // - reference: We allow references to classes that are not part of the compilation
        addBooleanOption("Xdoclint:all,-missing,-reference", true)

        // Add support for custom tags
        tags("apiNote:a:API Note:", "implSpec:a:Implementation Requirements:", "implNote:a:Implementation Note:")

        // Process all source files for valid javadoc, not just public ones
        addBooleanOption("private", true)

taa.it
tab
tabayama.yamanashi.jp
tabitorder.co.il
tabuse.yamaguchi.jp
tachiarai.fukuoka.jp
tachikawa.tokyo.jp
tadaoka.osaka.jp
tado.mie.jp
tadotsu.kagawa.jp
tagajo.miyagi.jp
tagami.niigata.jp
tagawa.fukuoka.jp
tahara.aichi.jp
taifun-dns.de
taiji.wakayama.jp
taiki.hokkaido.jp
taiki.mie.jp
tainai.niigata.jp
taipei
taira.toyama.jp
taishi.hyogo.jp
taishi.osaka.jp

		return
	}
	start := strings.LastIndex(s, "[")
	o.Marker = s[:start]
	end := strings.LastIndex(s, "]")
	tag := strings.Trim(s[start:end], "[]")
	tags := strings.SplitSeq(tag, ",")
	for tag := range tags {
		kv := strings.Split(tag, ":")
		if len(kv) < 2 {
			continue
		}
		switch kv[0] {
		case "minio_cache":
			if kv[1] != markerTagVersion {
				continue
			}
		case "id":

这将引用 `app/` 的往上一级，带有其自己的 `__init __.py` 等文件的某个包。但是我们并没有这个包。因此，这将在我们的示例中引发错误。🚨

但是现在你知道了它的工作原理，因此无论它们多么复杂，你都可以在自己的应用程序中使用相对导入。🤓

### 添加一些自定义的 `tags`、`responses` 和 `dependencies`

我们不打算在每个*路径操作*中添加前缀 `/items` 或 `tags =["items"]`，因为我们将它们添加到了 `APIRouter` 中。

但是我们仍然可以添加*更多*将会应用于特定的*路径操作*的 `tags`，以及一些特定于该*路径操作*的额外 `responses`：

```Python hl_lines="30-31" title="app/routers/items.py"
{!../../docs_src/bigger_applications/app/routers/items.py!}

Committer -5 The Apache Software License, Version 2.0 http://www.apache.org/licenses/LICENSE-2.0.txt repo scm:svn:http://svn.apache.org/repos/asf/maven/components/tags/maven-2.0/maven-plugin-api scm:svn:https://svn.apache.org/repos/asf/maven/components/tags/maven-2.0/maven-plugin-api http://svn.apache.org/viewcvs.cgi/maven/components/tags/maven-2.0/maven-plugin-api Apache Software Foundation http://www.apache.org/ c:\home\Brett\cvs\maven-2\maven-components-release\maven-plugin-api\src\main\java src/main/scripts...

## Etiquetas de Documentación - OpenAPI { #documentation-tags-openapi }

Para agregar etiquetas a tus *path operations*, y agruparlas en la interfaz de usuario de la documentación, lee la documentación para [Tutorial - Configuraciones de Path Operation - Etiquetas](../tutorial/path-operation-configuration.md#tags){.internal-link target=_blank}.

app = FastAPI()


class FilterParams(BaseModel):
    limit: int = Field(100, gt=0, le=100)
    offset: int = Field(0, ge=0)
    order_by: Literal["created_at", "updated_at"] = "created_at"
    tags: list[str] = []


@app.get("/items/")
async def read_items(filter_query: FilterParams = Query()):