from typing import Annotated, Union

from fastapi import Cookie, FastAPI

app = FastAPI()


@app.get("/items/")
async def read_items(ads_id: Annotated[Union[str, None], Cookie()] = None):

from typing import Annotated, Union

from fastapi import FastAPI, Header

app = FastAPI()


@app.get("/items/")
async def read_items(user_agent: Annotated[Union[str, None], Header()] = None):

from typing import Annotated

from fastapi import FastAPI, Header

app = FastAPI()


@app.get("/items/")
async def read_items(x_token: Annotated[list[str] | None, Header()] = None):

from typing import Union

from fastapi import FastAPI, Header
from typing_extensions import Annotated

app = FastAPI()


@app.get("/items/")
async def read_items(
    strange_header: Annotated[
        Union[str, None], Header(convert_underscores=False)
    ] = None,
):

from typing import List, Union

from fastapi import FastAPI, Query
from typing_extensions import Annotated

app = FastAPI()


@app.get("/items/")
async def read_items(q: Annotated[Union[List[str], None], Query()] = None):
    query_items = {"q": q}

from fastapi import FastAPI, Form
from pydantic import BaseModel
from typing_extensions import Annotated

app = FastAPI()


class FormData(BaseModel):
    username: str
    password: str
    model_config = {"extra": "forbid"}


@app.post("/login/")
async def login(data: Annotated[FormData, Form()]):

from typing import Annotated

from fastapi import FastAPI, Form
from pydantic import BaseModel

app = FastAPI()


class FormData(BaseModel):
    username: str
    password: str
    model_config = {"extra": "forbid"}


@app.post("/login/")
async def login(data: Annotated[FormData, Form()]):

from typing import Annotated

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(q: Annotated[str, Query(min_length=3)] = ...):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

from typing import Annotated

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(q: Annotated[str, Query(min_length=3)] = "fixedquery"):
    results = {"items": [{"item_id": "Foo"}, {"item_id": "Bar"}]}
    if q:
        results.update({"q": q})

//// tab | Python 3.10+ nicht annotiert

/// tip | "Tipp"

Bevorzugen Sie die `Annotated`-Version, falls möglich.

///

```Python hl_lines="6  47  54-55  58-59  68-74"
{!> ../../docs_src/security/tutorial004_py310.py!}
```

////

//// tab | Python 3.8+ nicht annotiert

/// tip | "Tipp"

Bevorzugen Sie die `Annotated`-Version, falls möglich.

///