}


@app.get(
    "/items/{item_id}/name",
    response_model=Item,
    response_model_include=["name", "description"],
)
async def read_item_name(item_id: str):
    return items[item_id]


@app.get("/items/{item_id}/public", response_model=Item, response_model_exclude=["tax"])
async def read_item_public_data(item_id: str):

from typing import Annotated

from fastapi import Header, HTTPException


async def get_token_header(x_token: Annotated[str, Header()]):
    if x_token != "fake-super-secret-token":
        raise HTTPException(status_code=400, detail="X-Token header invalid")


async def get_query_token(token: str):
    if token != "jessica":

    name: str
    price: float


class ResponseMessage(BaseModel):
    message: str


@app.post("/items/", response_model=ResponseMessage)
async def create_item(item: Item):
    return {"message": "item received"}


@app.get("/items/", response_model=list[Item])
async def get_items():
    return [
        {"name": "Plumbus", "price": 3},
        {"name": "Portal Gun", "price": 9001},

### Files and Async { #files-and-async }

In most cases, file-like objects are not compatible with async and await by default.

For example, they don't have an `await file.read()`, or `async for chunk in file`.

                input.value = ''
                event.preventDefault()
            }
        </script>
    </body>
</html>
"""


@app.get("/")
async def get():
    return HTMLResponse(html)


async def get_cookie_or_token(
    websocket: WebSocket,
    session: Annotated[str | None, Cookie()] = None,
    token: Annotated[str | None, Query()] = None,
):

    "baz": {"name": "Baz", "description": None, "price": 50.2, "tax": 10.5, "tags": []},
}


@app.get("/items/{item_id}", response_model=Item)
async def read_item(item_id: str):
    return items[item_id]


@app.patch("/items/{item_id}")
async def update_item(item_id: str, item: Item) -> Item:
    stored_item_data = items[item_id]
    stored_item_model = Item(**stored_item_data)

///

### Non-async *path operation functions* { #non-async-path-operation-functions }

You can also use regular `def` functions (without `async`), and use `yield` the same way.

FastAPI will make sure it's run correctly so that it doesn't block the event loop.

As in this case the function is not async, the right return type would be `Iterable[Item]`:

    def __init__(
        self, app: ASGIApp, context_name: str = "fastapi_middleware_astack"
    ) -> None:
        self.app = app
        self.context_name = context_name

    async def __call__(self, scope: Scope, receive: Receive, send: Send) -> None:
        async with AsyncExitStack() as stack:
            scope[self.context_name] = stack

app = FastAPI()


@app.exception_handler(UnicornException)
async def unicorn_exception_handler(request: Request, exc: UnicornException):
    return JSONResponse(
        status_code=418,
        content={"message": f"Oops! {exc.name} did something. There goes a rainbow..."},
    )


@app.get("/unicorns/{name}")
async def read_unicorn(name: str):
    if name == "yolo":
        raise UnicornException(name=name)

from fastapi.routing import APIRoute


class ValidationErrorLoggingRoute(APIRoute):
    def get_route_handler(self) -> Callable:
        original_route_handler = super().get_route_handler()

        async def custom_route_handler(request: Request) -> Response:
            try:
                return await original_route_handler(request)
            except RequestValidationError as exc:
                body = await request.body()