Let's say you have a *path operation* with a path `/files/{file_path}`.

But you need `file_path` itself to contain a *path*, like `home/johndoe/myfile.txt`.

So, the URL for that file would be something like: `/files/home/johndoe/myfile.txt`.

### OpenAPI support

OpenAPI doesn't support a way to declare a *path parameter* to contain a *path* inside, as that could lead to scenarios that are difficult to test and define.

| `terms_of_service` | `str` | A URL to the Terms of Service for the API. If provided, this has to be a URL. |

Do mesmo modo, você pode definir a lógica (código) que será executada quando a aplicação estiver sendo **encerrada**. Nesse caso, este código será executado **uma vez**, **depois** de ter possivelmente tratado **várias requisições**.

## The normal **FastAPI** app

Let's first see how the normal API app would look like before adding the callback.

It will have a *path operation* that will receive an `Invoice` body, and a query parameter `callback_url` that will contain the URL for the callback.

This part is pretty normal, most of the code is probably already familiar to you:

```Python hl_lines="9-13  36-53"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

!!! tip

/**
 * termynal.js
 *
 * @author Ines Montani <******@****.***>
 * @version 0.0.1
 * @license MIT
 */

:root {
    --color-bg: #252a33;
    --color-text: #eee;
    --color-text-subtle: #a2a2a2;
}

[data-termynal] {
    width: 750px;
    max-width: 100%;
    background: var(--color-bg);
    color: var(--color-text);
    /* font-size: 18px; */
    font-size: 15px;

/**
 * termynal.js
 * A lightweight, modern and extensible animated terminal window, using
 * async/await.
 *
 * @author Ines Montani <******@****.***>
 * @version 0.0.1
 * @license MIT
 */

'use strict';

/** Generate a terminal widget. */
class Termynal {
    /**
     * Construct the widget's settings.
     * @param {(string|Node)=} container - Query selector or container element.
     * @param {Object=} options - Custom settings.

!!! tip
    Keep in mind that JSON only supports `str` as keys.

    But Pydantic has automatic data conversion.

    This means that, even though your API clients can only send strings as keys, as long as those strings contain pure integers, Pydantic will convert them and validate them.

    And the `dict` you receive as `weights` will actually have `int` keys and `float` values.

## Recap

Você pode escrever <a href="https://en.wikipedia.org/wiki/Markdown" class="external-link" target="_blank">Markdown</a> na docstring, ele será interpretado e exibido corretamente (levando em conta a indentação da docstring).

=== "Python 3.8 and above"

    ```Python hl_lines="19-27"
    {!> ../../../docs_src/path_operation_configuration/tutorial004.py!}
    ```

=== "Python 3.9 and above"

Conversas no chat não são tão fáceis de serem encontrados quanto no GitHub, então questões e respostas podem se perder dentro da conversa. E apenas as que estão nas questões do GitHub contam para você se tornar um [Expert em FastAPI](fastapi-people.md#especialistas){.internal-link target=_blank}, então você receberá mais atenção nas questões do GitHub.

    * Eğer Starlette'i karşılaştırıyorsanız, Sanic, Flask, Django, vb. frameworkler (veya mikroframeworkler) ile karşılaştırın.
* **FastAPI**:
    * Starlette'in Uvicorn'u kullandığı ve ondan daha hızlı olamayacağı gibi, **FastAPI**'da Starlette'i kullanır, dolayısıyla ondan daha hızlı olamaz.