* Vérifier qu'il a un attribut facultatif `is_offer`, qui devrait être un `bool`, s'il est présent.
    * Tout cela fonctionnerait également pour les objets <abbr title="JavaScript Object Notation">JSON</abbr> profondément imbriqués.
* Convertir de et vers <abbr title="JavaScript Object Notation">JSON</abbr> automatiquement.
* Documenter tout avec OpenAPI, qui peut être utilisé par :
    * Les systèmes de documentation interactifs.

---

"_If you're looking to learn one **modern framework** for building REST APIs, check out **FastAPI** [...] It's fast, easy to use and easy to learn [...]_"

"_We've switched over to **FastAPI** for our **APIs** [...] I think you'll like it [...]_"

* Интерактивная документация API будет автоматически обновляться, включая новое тело:

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-03-swagger-02.png)

* Нажмите на кнопку "Try it out", это позволит вам заполнить параметры и напрямую взаимодействовать с API:

![Swagger UI interaction](https://fastapi.tiangolo.com/img/index/index-04-swagger-03.png)

* 交互式 API 文档将会自动更新，并加入新的请求体：

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-03-swagger-02.png)

* 点击「Try it out」按钮，之后你可以填写参数并直接调用 API：

![Swagger UI interaction](https://fastapi.tiangolo.com/img/index/index-04-swagger-03.png)

* 然后点击「Execute」按钮，用户界面将会和 API 进行通信，发送参数，获取结果并在屏幕上展示：

---

"_If you're looking to learn one **modern framework** for building REST APIs, check out **FastAPI** [...] It's fast, easy to use and easy to learn [...]_"

"_We've switched over to **FastAPI** for our **APIs** [...] I think you'll like it [...]_"

---

"_If you're looking to learn one **modern framework** for building REST APIs, check out **FastAPI** [...] It's fast, easy to use and easy to learn [...]_"

"_We've switched over to **FastAPI** for our **APIs** [...] I think you'll like it [...]_"

* There can be **multiple processes** of the **same program** running at the same time.

If you check out the "task manager" or "system monitor" (or similar tools) in your operating system, you will be able to see many of those processes running.

* ✨ Add FastAPI CLI, the new `fastapi` command. PR [#11522](https://github.com/tiangolo/fastapi/pull/11522) by [@tiangolo](https://github.com/tiangolo).
    * New docs: [FastAPI CLI](https://fastapi.tiangolo.com/fastapi-cli/).

Try it out with:

```console
$ pip install --upgrade fastapi

$ fastapi dev main.py


 ╭────────── FastAPI CLI - Development mode ───────────╮
 │                                                     │

    {!> ../../../docs_src/websockets/tutorial003_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="81-83"
    {!> ../../../docs_src/websockets/tutorial003.py!}
    ```

To try it out:

* Open the app with several browser tabs.
* Write messages from them.
* Then close one of the tabs.

That will raise the `WebSocketDisconnect` exception, and all the other clients will receive a message like:

* A documentação interativa da API será automaticamente atualizada, incluindo o novo corpo:

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-03-swagger-02.png)

* Clique no botão "Try it out", ele permitirá que você preencha os parâmetros e interaja diretamente com a API:

![Swagger UI interaction](https://fastapi.tiangolo.com/img/index/index-04-swagger-03.png)