client = TestClient(mod.app)
    client.headers.clear()
    return client


def test_get(client: TestClient):
    response = client.post(
        "/invoices/", json={"id": "fooinvoice", "customer": "John", "total": 5.3}
    )
    assert response.status_code == 200, response.text
    assert response.json() == {"msg": "Invoice received"}


def test_dummy_callback(mod: ModuleType):
    # Just for coverage

from fastapi import FastAPI
from fastapi.responses import ORJSONResponse

app = FastAPI()


@app.get("/items/", response_class=ORJSONResponse)
async def read_items():

        "/items/": {
            "get": {
                "summary": "Read Items",
                "operationId": "read_items_items__get",
                "responses": {
                    "200": {
                        "description": "Successful Response",
                        "content": {
                            "application/json": {
                                "schema": {}
                            }

By declaring `response_class=HTMLResponse` the docs UI will be able to know that the response will be HTML.

///

/// note | Technical Details

You could also use `from starlette.templating import Jinja2Templates`.

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

///

Ви отримаєте, як і було оголошено, `list` із `bytes` або `UploadFile`.

/// note | Технічні деталі

Ви також можете використати `from starlette.responses import HTMLResponse`.

**FastAPI**  надає ті ж самі `starlette.responses`, що й `fastapi.responses`, для зручності розробників. Однак більшість доступних відповідей надходять безпосередньо від Starlette.

///

from fastapi import FastAPI
from fastapi.responses import JSONResponse

app = FastAPI()


@app.get("/headers/")
def get_headers():
    content = {"message": "Hello World"}
    headers = {"X-Cat-Dog": "alone in the world", "Content-Language": "en-US"}

    ```

 *  New: Make the content-type header optional for request bodies.
 *  New: `Response.isSuccessful()` is a convenient API to check response codes.
 *  New: The response body can now be read outside of the callback. Response
    bodies must always be closed, otherwise they will leak connections!
 *  New: APIs to create multipart request bodies (`MultipartBuilder`) and form

De la misma manera, puedes declarar responses de listas de objetos.

Para eso, usa el `typing.List` estándar de Python (o simplemente `list` en Python 3.9 y posteriores):

{* ../../docs_src/extra_models/tutorial004_py39.py hl[18] *}


## Response con `dict` arbitrario { #response-with-arbitrary-dict }

* `expose_headers` - Indicate any response headers that should be made accessible to the browser. Defaults to `[]`.
* `max_age` - Sets a maximum time in seconds for browsers to cache CORS responses. Defaults to `600`.

The middleware responds to two particular types of HTTP request...

### CORS preflight requests { #cors-preflight-requests }

     * Used to convert validation messages to localized text for API responses.
     */
    @Resource
    protected MessageManager messageManager;

    /**
     * Service for managing API access tokens including validation and authentication.
     * Used to verify token-based authentication for API requests.
     */
    @Resource
    protected AccessTokenService accessTokenService;