This will (let's imagine) let the API user (some external developer) create an
    invoice.

    And this path operation will:

    * Send the invoice to the client.
    * Collect the money from the client.
    * Send a notification back to the API user (the external developer), as a callback.
        * At this point is that the API will somehow send a POST request to the
            external API with the notification of the invoice event

### Revísalo

Abre tu navegador en <a href="http://127.0.0.1:8000" class="external-link" target="_blank">http://127.0.0.1:8000</a>.

Verás la respuesta en JSON:

```JSON
{"message": "Hello World"}
```

### Documentación interactiva de la API

Ahora dirígete a <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

Ouvrez votre navigateur à l'adresse <a href="http://127.0.0.1:8000" class="external-link" target="_blank">http://127.0.0.1:8000</a>.

Vous obtiendrez cette réponse JSON :

```JSON
{"message": "Hello World"}
```

### Documentation interactive de l'API

Rendez-vous sur <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

### Confira

Abra o seu navegador em <a href="http://127.0.0.1:8000" class="external-link" target="_blank">http://127.0.0.1:8000</a>.

Você verá essa resposta em JSON:

```JSON
{"message": "Hello World"}
```

### Documentação Interativa de APIs

Agora vá para <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

## 🔗 ⏮️ 📕

👆 💪 🔗 ⏮️ <a href="https://tiangolo.com" class="external-link" target="_blank">👤 (🇹🇦 🇩🇬 / `tiangolo`)</a>, 📕.

👆 💪:

* <a href="https://github.com/tiangolo" class="external-link" target="_blank">⏩ 👤 🔛 **📂**</a>.
    * 👀 🎏 📂 ℹ 🏗 👤 ✔️ ✍ 👈 💪 ℹ 👆.
    * ⏩ 👤 👀 🕐❔ 👤 ✍ 🆕 📂 ℹ 🏗.

* Schauen Sie nach <a href="https://github.com/fastapi/fastapi/pulls" class="external-link" target="_blank">aktuellen Pull Requests</a> für Ihre Sprache. Sie können die Pull Requests nach dem Label für Ihre Sprache filtern. Für Spanisch lautet das Label beispielsweise <a href="https://github.com/fastapi/fastapi/pulls?q=is%3Aopen+sort%3Aupdated-desc+label%3Alang-es+label%3Aawaiting-review" class="external-link" target="_blank">`lang-es`</a>.

* Once you think the PR is ready, move it in the internal GitHub project for me to review it.

## FastAPI People PRs

Every month, a GitHub Action updates the FastAPI People data. Those PRs look like this one: <a href="https://github.com/fastapi/fastapi/pull/11669" class="external-link" target="_blank">👥 Update FastAPI People</a>.

If the tests are passing, you can merge it right away.

## External Links PRs

Es por esto que **FastAPI** mismo provee una documentación alternativa de la API (usando ReDoc), a la que puedes acceder en <a href="http://127.0.0.1:8000/redoc" class="external-link" target="_blank">http://127.0.0.1:8000/redoc</a>:

<img src="/img/tutorial/path-params/image02.png">

///

## Mais informações

Para aprender mais sobre as opções, verifique a documentação do Starlette para:

* <a href="https://www.starlette.io/websockets/" class="external-link" target="_blank">A classe `WebSocket`</a>.

Существует три наиболее распространённые альтернативы:

* <a href="https://www.uvicorn.org/" class="external-link" target="_blank">Uvicorn</a>: высокопроизводительный ASGI сервер.
* <a href="https://hypercorn.readthedocs.io/" class="external-link" target="_blank">Hypercorn</a>: ASGI сервер, помимо прочего поддерживающий HTTP/2 и Trio.
* <a href="https://github.com/django/daphne" class="external-link" target="_blank">Daphne</a>: ASGI сервер, созданный для Django Channels.