* Beide _Pfade_ nehmen `GET` Operationen (auch bekannt als HTTP-_Methoden_) entgegen.
* Der _Pfad_ `/items/{item_id}` hat einen _Pfad-Parameter_ `item_id`, der ein `int` sein sollte.
* Der _Pfad_ `/items/{item_id}` hat einen optionalen `str`-_Query-Parameter_ `q`.

from pydantic import BaseModel


class Item(BaseModel):
    id: str
    value: str


responses = {
    404: {"description": "Item not found"},
    302: {"description": "The item was moved"},
    403: {"description": "Not enough privileges"},
}


app = FastAPI()


@app.get(
    "/items/{item_id}",
    response_model=Item,
    responses={**responses, 200: {"content": {"image/png": {}}}},

    }


def test_encode_dataclass():
    item = Item(name="foo", count=100)
    assert jsonable_encoder(item) == {"name": "foo", "count": 100}
    assert jsonable_encoder(item, include={"name"}) == {"name": "foo"}
    assert jsonable_encoder(item, exclude={"count"}) == {"name": "foo"}
    assert jsonable_encoder(item, include={}) == {}
    assert jsonable_encoder(item, exclude={}) == {"name": "foo", "count": 100}

from fastapi import FastAPI
from pydantic import BaseModel


class Item(BaseModel):
    name: str
    description: Optional[str] = None


app = FastAPI(separate_input_output_schemas=False)


@app.post("/items/")
def create_item(item: Item):
    return item


@app.get("/items/")
def read_items() -> list[Item]:
    return [
        Item(
            name="Portal Gun",

from fastapi import FastAPI, Query

app = FastAPI()


@app.get("/items/")
async def read_items(
    q: str | None = Query(
        default=None,
        alias="item-query",
        title="Query string",
        description="Query string for the items to search in the database that have a good match",
        min_length=3,
        max_length=50,
        pattern="^fixedquery$",
        deprecated=True,
    ),
):

        raise HTTPException(status_code=404, detail="Item not found")
    return fake_db[item_id]


@app.post("/items/", response_model=Item)
async def create_item(item: Item, x_token: str = Header()):
    if x_token != fake_secret_token:
        raise HTTPException(status_code=400, detail="Invalid X-Token header")
    if item.id in fake_db:
        raise HTTPException(status_code=409, detail="Item already exists")
    fake_db[item.id] = item

        raise HTTPException(status_code=404, detail="Item not found")
    return fake_db[item_id]


@app.post("/items/", response_model=Item)
async def create_item(item: Item, x_token: str = Header()):
    if x_token != fake_secret_token:
        raise HTTPException(status_code=400, detail="Invalid X-Token header")
    if item.id in fake_db:
        raise HTTPException(status_code=409, detail="Item already exists")
    fake_db[item.id] = item

@app.get("/items/{item_id}")
def get_item(item_id: str, username: Annotated[str, Depends(get_username)]):
    if item_id not in data:
        raise HTTPException(status_code=404, detail="Item not found")
    item = data[item_id]
    if item["owner"] != username:
        raise OwnerError(username)

            function connect(event) {
                var itemId = document.getElementById("itemId")
                var token = document.getElementById("token")
                ws = new WebSocket("ws://localhost:8000/items/" + itemId.value + "/ws?token=" + token.value);
                ws.onmessage = function(event) {
                    var messages = document.getElementById('messages')
                    var message = document.createElement('li')

        raise HTTPException(status_code=404, detail="Item not found")
    return fake_db[item_id]


@app.post("/items/", response_model=Item)
async def create_item(item: Item, x_token: Annotated[str, Header()]):
    if x_token != fake_secret_token:
        raise HTTPException(status_code=400, detail="Invalid X-Token header")
    if item.id in fake_db:
        raise HTTPException(status_code=409, detail="Item already exists")
    fake_db[item.id] = item