body:
  - type: markdown
    attributes:
      value: |
        Thanks for your interest in FastAPI! 🚀

        If you are not @tiangolo or he didn't ask you directly to create an issue here, please start the conversation in a [Question in GitHub Discussions](https://github.com/fastapi/fastapi/discussions/categories/questions) instead.
  - type: checkboxes
    id: privileged
    attributes:
      label: Privileged issue

from dataclasses import field  # (1)

from fastapi import FastAPI
from pydantic.dataclasses import dataclass  # (2)


@dataclass
class Item:
    name: str
    description: str | None = None


@dataclass
class Author:
    name: str
    items: list[Item] = field(default_factory=list)  # (3)


app = FastAPI()


@app.post("/authors/{author_id}/items/", response_model=Author)  # (4)

from dataclasses import field  # (1)
from typing import Union

from fastapi import FastAPI
from pydantic.dataclasses import dataclass  # (2)


@dataclass
class Item:
    name: str
    description: Union[str, None] = None


@dataclass
class Author:
    name: str
    items: list[Item] = field(default_factory=list)  # (3)


app = FastAPI()


@app.post("/authors/{author_id}/items/", response_model=Author)  # (4)

`swagger_ui_parameters` empfängt ein <abbr title="Dictionary – Zuordnungstabelle: In anderen Sprachen auch Hash, Map, Objekt, Assoziatives Array genannt">Dictionary</abbr> mit den Konfigurationen, die direkt an die Swagger-Oberfläche übergeben werden.

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

app = FastAPI()

client = TestClient(app)


class Item(BaseModel):
    data: str


def duplicate_dependency(item: Item):
    return item


def dependency(item2: Item):
    return item2


def sub_duplicate_dependency(
    item: Item, sub_item: Item = Depends(duplicate_dependency)
):

from typing import Annotated, Union

from fastapi import Body, FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: Union[str, None] = None
    price: float
    tax: Union[float, None] = None


class User(BaseModel):
    username: str
    full_name: Union[str, None] = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,

Wenn Sie einen anderen Anwendungsfall haben, der ein frühes Beenden aus einer Abhängigkeit mit `yield` benötigt, erstellen Sie bitte eine <a href="https://github.com/fastapi/fastapi/discussions/new?category=questions" class="external-link" target="_blank">GitHub-Diskussion-Frage</a> mit Ihrem spezifischen Anwendungsfall und warum Sie von einem frühen Schließen für Abhängigkeiten mit `yield` profitieren würden.

from typing import Annotated

from fastapi import FastAPI, File, UploadFile
from fastapi.responses import HTMLResponse

app = FastAPI()


@app.post("/files/")
async def create_files(files: Annotated[list[bytes], File()]):
    return {"file_sizes": [len(file) for file in files]}


@app.post("/uploadfiles/")
async def create_upload_files(files: list[UploadFile]):
    return {"filenames": [file.filename for file in files]}

new_app = UnicornMiddleware(app, some_config="rainbow")
```

Pero FastAPI (en realidad Starlette) proporciona una forma más simple de hacerlo que asegura que los middlewares internos manejen errores del servidor y los controladores de excepciones personalizadas funcionen correctamente.

Para eso, usas `app.add_middleware()` (como en el ejemplo para CORS).

```Python
from fastapi import FastAPI
from unicorn import UnicornMiddleware

app = FastAPI()

![ReDoc](https://fastapi.tiangolo.com/img/index/index-02-redoc-simple.png)

## Construa uma Imagem Docker com um FastAPI de Arquivo Único { #build-a-docker-image-with-a-single-file-fastapi }

Se seu FastAPI for um único arquivo, por exemplo, `main.py` sem um diretório `./app`, sua estrutura de arquivos poderia ser assim:

```
.