Keep in mind that this means that the whole contents will be stored in memory. This will work well for small files.

But there are several cases in which you might benefit from using `UploadFile`.

## File Parameters with `UploadFile`

Define a file parameter with a type of `UploadFile`:

=== "Python 3.9+"

    ```Python hl_lines="14"

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python hl_lines="20"
    {!> ../../../docs_src/dependencies/tutorial011.py!}
    ```

!!! tip
    All this might seem contrived. And it might not be very clear how is it useful yet.

    These examples are intentionally simple, but show how it all works.

## Reporting a Vulnerability

If you think you found a vulnerability, and even if you are not sure about it, please report it right away by sending an email to: ******@****.***. Please try to be as explicit as possible, describing all the steps and example code to reproduce the security issue.

And it shows their true commitment to FastAPI and its **community** (you), as they not only want to provide you a **good service** but also want to make sure you have a **good and healthy framework**, FastAPI. 🙇

You might want to try their services and follow their guides:

# JSON Compatible Encoder

There are some cases where you might need to convert a data type (like a Pydantic model) to something compatible with JSON (like a `dict`, `list`, etc).

For example, if you need to store it in a database.

For that, **FastAPI** provides a `jsonable_encoder()` function.

## Using the `jsonable_encoder`

Let's imagine that you have a database `fake_db` that only receives JSON compatible data.

In most cases you would (and should) have a "termination proxy" handling HTTPS for you on top, this will depend on how you deploy your application, your provider might do this for you, or you might need to set it up yourself.

!!! tip

And to communicate using WebSockets with your backend you would probably use your frontend's utilities.

Or you might have a native mobile application that communicates with your WebSocket backend directly, in native code.

Or you might have any other way to communicate with the WebSocket endpoint.

---

This can make it a lot easier for your users to **implement their APIs** to receive your **webhook** requests, they might even be able to autogenerate some of their own API code.

!!! info
    Webhooks are available in OpenAPI 3.1.0 and above, supported by FastAPI `0.99.0` and above.

## An app with webhooks

The whole **FastAPI** framework is based to satisfy that. Autocompletion works everywhere.

You will rarely need to come back to the docs.

Here's how your editor might help you:

* in <a href="https://code.visualstudio.com/" class="external-link" target="_blank">Visual Studio Code</a>:

![editor support](https://fastapi.tiangolo.com/img/vscode-completion.png)

    Some editors check for unused function parameters, and show them as errors.

    Using these `dependencies` in the *path operation decorator* you can make sure they are executed while avoiding editor/tooling errors.

    It might also help avoid confusion for new developers that see an unused parameter in your code and could think it's unnecessary.

!!! info
    In this example we use invented custom headers `X-Key` and `X-Token`.