)


async def get_token(token: Annotated[str, Depends(oauth2_scheme)]) -> str:
    return token


app = FastAPI(dependencies=[Depends(get_token)])


@app.get("/admin", dependencies=[Security(get_token, scopes=["read", "write"])])
async def read_admin():
    return {"message": "Admin Access"}


client = TestClient(app)


def test_read_admin():

然后，依赖项函数返回包含这些值的 `dict`。

### 导入 `Depends`

{* ../../docs_src/dependencies/tutorial001.py hl[3] *}

### 声明依赖项

与在*路径操作函数*参数中使用 `Body`、`Query` 的方式相同，声明依赖项需要使用 `Depends` 和一个新的参数：

{* ../../docs_src/dependencies/tutorial001.py hl[15,20] *}

虽然，在路径操作函数的参数中使用 `Depends` 的方式与 `Body`、`Query` 相同，但 `Depends` 的工作方式略有不同。

这里只能传给 Depends 一个参数。

且该参数必须是可调用对象，比如函数。

该函数接收的参数和*路径操作函数*的参数一样。

In Version 0.121.0 hat FastAPI Unterstützung für `Depends(scope="function")` für Abhängigkeiten mit `yield` hinzugefügt.

Mit `Depends(scope="function")` wird der Exit-Code nach `yield` direkt nach dem Ende der *Pfadoperation-Funktion* ausgeführt, bevor die Response an den Client gesendet wird.

from typing import Optional

from fastapi import Depends, FastAPI, Security
from fastapi.security import APIKeyQuery
from fastapi.testclient import TestClient
from pydantic import BaseModel

app = FastAPI()

api_key = APIKeyQuery(name="key", auto_error=False)


class User(BaseModel):
    username: str


def get_current_user(oauth_header: Optional[str] = Security(api_key)):
    if oauth_header is None:
        return None

from typing import Optional

from fastapi import Depends, FastAPI, Security
from fastapi.security import APIKeyCookie
from fastapi.testclient import TestClient
from pydantic import BaseModel

app = FastAPI()

api_key = APIKeyCookie(name="key", auto_error=False)


class User(BaseModel):
    username: str


def get_current_user(oauth_header: Optional[str] = Security(api_key)):
    if oauth_header is None:
        return None

    skipped_paths: list[Path] = []
    for p in paths_to_process:
        lang_path = generate_lang_path(lang=language, path=p)
        if lang_path.exists():
            skipped_paths.append(p)
            continue
        missing_paths.append(p)
    print("Paths to skip:")
    for p in skipped_paths:
        print(f"  - {p}")
    print(f"Total paths to skip: {len(skipped_paths)}")
    print("Paths to process:")

from typing import Annotated, TypeVar

from fastapi import Depends, FastAPI
from fastapi.testclient import TestClient

app = FastAPI()

T = TypeVar("T")

Dep = Annotated[T, Depends()]


class A:
    pass


class B:
    pass


@app.get("/a")
async def a(dep: Dep[A]):
    return {"cls": dep.__class__.__name__}


@app.get("/b")
async def b(dep: Dep[B]):
    return {"cls": dep.__class__.__name__}

    client_tag: Optional[str] = Depends(_get_client_tag),
):
    return {"client_id": client_key, "client_tag": client_tag}


client = TestClient(app)

expected_schema = {
    "components": {
        "schemas": {
            "HTTPValidationError": {
                "properties": {
                    "detail": {
                        "items": {"$ref": "#/components/schemas/ValidationError"},

                messageBuffer
                        .append("<configuration>")
                        .append(LS)
                        .append("  ...")
                        .append(LS);
                messageBuffer
                        .append("  <")
                        .append(alias)
                        .append(">VALUE</")
                        .append(alias)

            buf.append(".html\">File ");
            buf.append(count);
            buf.append("-");
            buf.append(i);
            buf.append("</a><br>");
            buf.append("<a href=\"dir");
            buf.append(count);
            buf.append("-");
            buf.append(i);
            buf.append("/index.html\">Dir ");
            buf.append(count);
            buf.append("-");