from typing import Annotated, Union

from fastapi import FastAPI, Header

app = FastAPI()


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

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(
    hidden_query: str | None = Query(default=None, include_in_schema=False),
):
    if hidden_query:
        return {"hidden_query": hidden_query}
    else:

# Verwendung von Datenklassen { #using-dataclasses }

FastAPI basiert auf **Pydantic**, und ich habe Ihnen gezeigt, wie Sie Pydantic-Modelle verwenden können, um <abbr title="Request – Anfrage: Daten, die der Client zum Server sendet">Requests</abbr> und <abbr title="Response – Antwort: Daten, die der Server zum anfragenden Client zurücksendet">Responses</abbr> zu deklarieren.

# Using Dataclasses { #using-dataclasses }

FastAPI is built on top of **Pydantic**, and I have been showing you how to use Pydantic models to declare requests and responses.

But FastAPI also supports using <a href="https://docs.python.org/3/library/dataclasses.html" class="external-link" target="_blank">`dataclasses`</a> the same way:

{* ../../docs_src/dataclasses_/tutorial001_py310.py hl[1,6:11,18:19] *}

Он импортируется/включается прямо в FastAPI, чтобы вы могли импортировать его из `fastapi` и избежать случайного импорта альтернативного `BackgroundTask` (без `s` на конце) из `starlette.background`.

Используя только `BackgroundTasks` (а не `BackgroundTask`), его можно применять как параметр функции‑обработчика пути, и **FastAPI** сделает остальное за вас, как при использовании объекта `Request` напрямую.

from fastapi import FastAPI, File, UploadFile

app = FastAPI()


@app.post("/files/")
async def create_file(file: bytes = File()):
    return {"file_size": len(file)}


@app.post("/uploadfile/")
async def create_upload_file(file: UploadFile):

    skip_module_if_py_gte_314()

from fastapi import FastAPI
from fastapi.exceptions import PydanticV1NotSupportedError

with warnings.catch_warnings():
    warnings.simplefilter("ignore", UserWarning)
    from pydantic.v1 import BaseModel


def test_raises_pydantic_v1_model_in_endpoint_param() -> None:
    class ParamModelV1(BaseModel):
        name: str

    app = FastAPI()

from contextvars import ContextVar
from typing import Any, Callable, Optional

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

legacy_request_state_context_var: ContextVar[Optional[dict[str, Any]]] = ContextVar(
    "legacy_request_state_context_var", default=None
)

app = FastAPI()


async def set_up_request_state_dependency():
    request_state = {"user": "deadpond"}

from typing import Union

from fastapi import Body, FastAPI, Query
from fastapi.testclient import TestClient

app = FastAPI()


@app.get("/query")
def read_query(q: Union[str, None]):
    return q


@app.get("/explicit-query")
def read_explicit_query(q: Union[str, None] = Query()):
    return q


@app.post("/body-embed")
def send_body_embed(b: Union[str, None] = Body(embed=True)):
    return b

Belki de öğrenme tarzınıza daha iyi uyduğu için başka kursları tercih edebilirsiniz.

Bazı kurs sağlayıcıları ✨ [**FastAPI destekçileridir**](../help-fastapi.md#sponsor-the-author){.internal-link target=_blank} ✨, bu FastAPI ve **ekosisteminin** sürekli ve sağlıklı bir şekilde **gelişmesini** sağlar.