# Custom Response Classes - File, HTML, Redirect, Streaming, etc.

There are several custom response classes you can use to create an instance and return them directly from your *path operations*.

Read more about it in the [FastAPI docs for Custom Response - HTML, Stream, File, others](https://fastapi.tiangolo.com/advanced/custom-response/).

You can import them directly from `fastapi.responses`:

```python
from fastapi.responses import (
    FileResponse,

There are some cases where you might need to modify the generated OpenAPI schema.

In this section you will see how.

## The normal process

The normal (default) process, is as follows.

A `FastAPI` application (instance) has an `.openapi()` method that is expected to return the OpenAPI schema.

As part of the application object creation, a *path operation* for `/openapi.json` (or for whatever you set your `openapi_url`) is registered.

Le mot "**serveur**" est couramment utilisé pour désigner à la fois l'ordinateur distant/cloud (la machine physique ou virtuelle) et également le programme qui s'exécute sur cette machine (par exemple, Uvicorn).

Gardez cela à l'esprit lorsque vous lisez "serveur" en général, cela pourrait faire référence à l'une de ces deux choses.

        pass

    class MyModel(BaseModel):
        dt_field: safe_datetime

    instance = MyModel(dt_field=safe_datetime.now())

    encoded_instance = jsonable_encoder(
        instance, custom_encoder={safe_datetime: lambda o: o.isoformat()}
    )
    assert encoded_instance["dt_field"] == instance.dt_field.isoformat()


def test_custom_enum_encoders():
    def custom_enum_encoder(v: Enum):

    the key value sent in the query parameter automatically and provides it as the
    dependency result. But it doesn't define how to send that API key to the client.

    ## Usage

    Create an instance object and use that object as the dependency in `Depends()`.

    The dependency result will be a string containing the key value.

    ## Example

    ```python
    from fastapi import Depends, FastAPI

# `Response` class

You can declare a parameter in a *path operation function* or dependency to be of type `Response` and then you can set data for the response like headers or cookies.

You can also use it directly to create an instance of it and return it from your *path operations*.

You can import it directly from `fastapi`:

```python
from fastapi import Response
```

│   ├── main.py
└── static
    ├── redoc.standalone.js
    ├── swagger-ui-bundle.js
    └── swagger-ui.css
```

### Serve the static files

* Import `StaticFiles`.
* "Mount" a `StaticFiles()` instance in a specific path.

```Python hl_lines="7  11"
{!../../../docs_src/custom_docs_ui/tutorial002.py!}
```

### Test the static files

Tú declaras la "forma" de los datos mediante clases con atributos.

Cada atributo tiene un tipo.

Luego creas un instance de esa clase con algunos valores y Pydantic validará los valores, los convertirá al tipo apropiado (si ese es el caso) y te dará un objeto con todos los datos.

Y obtienes todo el soporte del editor con el objeto resultante.

    That when called, return instances of classes of the same name.

    So, you import `Query`, which is a function. And when you call it, it returns an instance of a class also named `Query`.

    These functions are there (instead of just using the classes directly) so that your editor doesn't mark errors about their types.

from starlette.requests import Request
from starlette.status import HTTP_403_FORBIDDEN
from typing_extensions import Annotated, Doc


class OpenIdConnect(SecurityBase):
    """
    OpenID Connect authentication class. An instance of it would be used as a
    dependency.
    """

    def __init__(
        self,
        *,
        openIdConnectUrl: Annotated[
            str,
            Doc(
                """