Aleksandr Andrukhov <******@****.***> 1705057939 +0300

Kani Kim <******@****.***> 1707659311 +0900

Nils Lindemann <******@****.***> 1711821718 +0100

SwftAlpc <******@****.***> 1705334896 +0900

So, a Python class is also a **callable**.

Then, in **FastAPI**, you could use a Python class as a dependency.

What FastAPI actually checks is that it is a "callable" (function, class or anything else) and the parameters defined.

If you pass a "callable" as a dependency in **FastAPI**, it will analyze the parameters for that "callable", and process them in the same way as the parameters for a *path operation function*. Including sub-dependencies.

LeeeeT <******@****.***> 1680341164 +0300

Sebastián Ramírez <******@****.***> 1697522351 +0400

def test_response_model_no_annotation_return_invalid_dict():
    with pytest.raises(ResponseValidationError) as excinfo:
        client.get("/response_model-no_annotation-return_invalid_dict")
    assert "missing" in str(excinfo.value)


def test_response_model_no_annotation_return_invalid_model():
    with pytest.raises(ResponseValidationError) as excinfo:
        client.get("/response_model-no_annotation-return_invalid_model")

                    <mxGeometry relative="1" as="geometry">
                        <mxPoint x="105" y="-280" as="sourcePoint"/>
                        <mxPoint x="390" y="-260" as="targetPoint"/>
                        <Array as="points">
                            <mxPoint x="390" y="-430"/>
                        </Array>
                    </mxGeometry>

## Adding ASGI middlewares

As **FastAPI** is based on Starlette and implements the <abbr title="Asynchronous Server Gateway Interface">ASGI</abbr> specification, you can use any ASGI middleware.

A middleware doesn't have to be made for FastAPI or Starlette to work, as long as it follows the ASGI spec.

In general, ASGI middlewares are classes that expect to receive an ASGI app as the first argument.