"item": {
            "name": "Foo",
            "price": 50.5,
            "description": None,
            "tax": None,
        },
        "user": {"username": "Dave", "full_name": None},
    }


def test_post_body_no_data(client: TestClient):
    response = client.put("/items/5", json=None)
    assert response.status_code == 422
    assert response.json() == {
        "detail": [
            {

        new LineProcessor<List<String>>() {
          final List<String> collector = new ArrayList<>();

          @Override
          public boolean processLine(String line) {
            if (line.length() > 0) {
              collector.add(line);
            }
            return true;
          }

          @Override
          public List<String> getResult() {
            return collector;
          }

Tatsächlich verwendet FastAPI diese beiden Dekoratoren intern.

///

## Eine Datenbank-Abhängigkeit mit `yield` { #a-database-dependency-with-yield }

Sie könnten damit beispielsweise eine Datenbanksession erstellen und diese nach Abschluss schließen.

from pydantic import BaseModel


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


app = FastAPI()


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item, q: Union[str, None] = None):
    result = {"item_id": item_id, **item.model_dump()}
    if q:
        result.update({"q": q})

from fastapi import Body, FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


class User(BaseModel):
    username: str
    full_name: str | None = None


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item, user: User, importance: int = Body()):

app = FastAPI()


class Image(BaseModel):
    url: HttpUrl
    name: str


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


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item):
    results = {"item_id": item_id, "item": item}

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None

    model_config = {
        "json_schema_extra": {
            "examples": [
                {
                    "name": "Foo",
                    "description": "A very nice Item",
                    "price": 35.4,
                    "tax": 3.2,
                }

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}
```

### Dockerfile { #dockerfile }

Now in the same project directory create a file `Dockerfile` with:

```{ .dockerfile .annotate }
# (1)!

      .assertRequestHeader("Accept-Language", "en-US")
      .assertRequestHeader("Accept-Charset", "UTF-8")
      .assertRequestHeader("If-None-Match") // No If-None-Match on the user's request.
      .assertSentRequestAtMillis(request2SentAt, request2ReceivedAt)
      .assertReceivedResponseAtMillis(request2SentAt, request2ReceivedAt)

    return "fakehashed" + password


oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")


class User(BaseModel):
    username: str
    email: str | None = None
    full_name: str | None = None
    disabled: bool | None = None


class UserInDB(User):
    hashed_password: str


def get_user(db, username: str):
    if username in db:
        user_dict = db[username]