* [Better with `Annotated`](https://fastapi.tiangolo.com/tutorial/path-params-numeric-validations/#better-with-annotated)
    * [Dependencies - First Steps - Share `Annotated` dependencies](https://fastapi.tiangolo.com/tutorial/dependencies/#share-annotated-dependencies)

    * You can also help to review the translations created by others.
* To propose new documentation sections.
* To fix an existing issue/bug.
    * Make sure to add tests.
* To add a new feature.
    * Make sure to add tests.
    * Make sure to add documentation if it's relevant.

## Help Maintain FastAPI

Help me maintain **FastAPI**! 🤓

There's a lot of work to do, and for most of it, **YOU** can do it.

This is very useful when you need to:

* Have shared logic (the same code logic again and again).
* Share database connections.
* Enforce security, authentication, role requirements, etc.
* And many other things...

All these, while minimizing code repetition.

## First Steps

## 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:

    * Um exemplo é `404`, para uma resposta "Não encontrado".
    * Para erros genéricos do cliente, você pode usar apenas `400`.
* `500` e acima são para erros do servidor. Você quase nunca os usa diretamente. Quando algo der errado em alguma parte do código do seu aplicativo ou servidor, ele retornará automaticamente um desses códigos de status.

!!! tip "Dica"

!!! tip
    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

<img src="/img/tutorial/path-operation-configuration/image01.png">

### Tags with Enums

If you have a big application, you might end up accumulating **several tags**, and you would want to make sure you always use the **same tag** for related *path operations*.

In these cases, it could make sense to store the tags in an `Enum`.

**FastAPI** supports that the same way as with plain strings:

```Python
callback_url = "https://example.com/api/v1/invoices/events/"
httpx.post(callback_url, json={"description": "Invoice paid", "paid": True})
```

But possibly the most important part of the callback is making sure that your API user (the external developer) implements the *external API* correctly, according to the data that *your API* is going to send in the request body of the callback, etc.

## What is "Form Data"

The way HTML forms (`<form></form>`) sends the data to the server normally uses a "special" encoding for that data, it's different from JSON.

**FastAPI** will make sure to read that data from the right place instead of JSON.

!!! note "Technical Details"
    Data from forms is normally encoded using the "media type" `application/x-www-form-urlencoded` when it doesn't include files.