```

## Additional Responses

You probably have seen how to declare the `response_model` and `status_code` for a *path operation*.

That defines the metadata about the main response of a *path operation*.

You can also declare additional responses with their models, status codes, etc.

from fastapi import FastAPI
from fastapi.responses import FileResponse
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,

        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '404':
          $ref: '#/components/responses/NotFound'
        '500':
          $ref: '#/components/responses/InternalServerError'

components:
  responses:
    BadRequest:
      description: Bad request
      content:

    if isinstance(route.response_class, DefaultPlaceholder):
        current_response_class: Type[Response] = route.response_class.value
    else:
        current_response_class = route.response_class
    assert current_response_class, "A response class is needed to generate OpenAPI"
    route_response_media_type: Optional[str] = current_response_class.media_type
    if route.include_in_schema:

Es enthält `tags`, `parameters`, `requestBody`, `responses`, usw.

Dieses *Pfadoperation*-spezifische OpenAPI-Schema wird normalerweise automatisch von **FastAPI** generiert, Sie können es aber auch erweitern.

!!! tip "Tipp"
    Dies ist ein Low-Level Erweiterungspunkt.

    Wenn Sie nur zusätzliche Responses deklarieren müssen, können Sie dies bequemer mit [Zusätzliche Responses in OpenAPI](additional-responses.md){.internal-link target=_blank} tun.

    * Wird in Requests und Responses als `str` dargestellt.
* `datetime.datetime`:
    * Ein Python-`datetime.datetime`.
    * Wird in Requests und Responses als `str` im ISO 8601-Format dargestellt, etwa: `2008-09-15T15:53:00+05:00`.
* `datetime.date`:
    * Python-`datetime.date`.
    * Wird in Requests und Responses als `str` im ISO 8601-Format dargestellt, etwa: `2008-09-15`.
* `datetime.time`:

	"fmt"
	"io"
	"net"
	"net/http"
	"time"
)

// ResponseRecorder - is a wrapper to trap the http response
// status code and to record the response body
type ResponseRecorder struct {
	http.ResponseWriter
	io.ReaderFrom
	StatusCode int
	// Log body of 4xx or 5xx responses
	LogErrBody bool
	// Log body of all responses
	LogAllBody bool

	TimeToFirstByte time.Duration
	StartTime       time.Time

      }
    }

    constructor(response: Response) {
      this.url = response.request.url
      this.varyHeaders = response.varyHeaders()
      this.requestMethod = response.request.method
      this.protocol = response.protocol
      this.code = response.code
      this.message = response.message
      this.responseHeaders = response.headers
      this.handshake = response.handshake

async def dep0(response: Response):
    response.headers["x-level0"] = "True"


async def dep1(response: Response):
    response.headers["x-level1"] = "True"


async def dep2(response: Response):
    response.headers["x-level2"] = "True"


async def dep3(response: Response):
    response.headers["x-level3"] = "True"


async def dep4(response: Response):

```

!!! note "Technical Details"
    You could also use `from starlette.requests import Request` and `from starlette.responses import JSONResponse`.

    **FastAPI** provides the same `starlette.responses` as `fastapi.responses` just as a convenience for you, the developer. But most of the available responses come directly from Starlette. The same with `Request`.

## Override the default exception handlers