response = client.get(
        "/items/bar?token=jessica", headers={"X-Token": "fake-super-secret-token"}
    )
    assert response.status_code == 404
    assert response.json() == {"detail": "Item not found"}


def test_items_plumbus_with_no_token(client: TestClient):
    response = client.get(
        "/items/plumbus", headers={"X-Token": "fake-super-secret-token"}
    )
    assert response.status_code == 422

    response = client.get(
        "/items/bar?token=jessica", headers={"X-Token": "fake-super-secret-token"}
    )
    assert response.status_code == 404
    assert response.json() == {"detail": "Item not found"}


@needs_py39
def test_items_plumbus_with_no_token(client: TestClient):
    response = client.get(
        "/items/plumbus", headers={"X-Token": "fake-super-secret-token"}
    )

Right before deciding to build **FastAPI** I found **APIStar** server. It had almost everything I was looking for and had a great design.

It was one of the first implementations of a framework using Python type hints to declare parameters and requests that I ever saw (before NestJS and Molten). I found it more or less at the same time as Hug. But APIStar used the OpenAPI standard.

```JSON
{
  "item": "The Foo Wrestlers"
}
```

しかし、クライアントが`http://example.com/items/bar`（存在しない`item_id` `"bar"`）をリクエストした場合、HTTPステータスコード404（"not found"エラー）と以下のJSONレスポンスが返されます:

```JSON
{
  "detail": "Item not found"
}
```

!!! tip "豆知識"
    `HTTPException`を発生させる際には、`str`だけでなく、JSONに変換できる任意の値を`detail`パラメータとして渡すことができます。

    `dist`や`list`などを渡すことができます。

 │  🐍 main.py          │
 │                      │
 ╰──────────────────────╯

<font color="#3465A4">INFO    </font> Importing module <font color="#4E9A06">main</font>
<font color="#3465A4">INFO    </font> Found importable FastAPI app

 ╭─ <font color="#8AE234"><b>Importable FastAPI app</b></font> ─╮
 │                          │

Le temps d'exécution étant consommé majoritairement par l'attente d'opérations <abbr title="Input/Output ou Entrées et Sorties ">I/O</abbr> on appelle ceci des opérations <a href="https://fr.wikipedia.org/wiki/I/O_bound" class="external-link" target="_blank">"I/O bound"</a>.

            logging.error(log_message)
            raise RuntimeError(log_message)
        discussion = lang_to_discussion_map[lang]
        logging.info(
            f"Found a translation discussion for language: {lang} in discussion: #{discussion.number}"
        )

        already_notified_comment: Union[Comment, None] = None
        already_done_comment: Union[Comment, None] = None

    * Generating **automatic errors** returned to the client when the data is invalid.
* **Document** the API using OpenAPI:
    * which is then used by the automatic interactive documentation user interfaces.

This might all sound abstract. Don't worry. You'll see all this in action in the [Tutorial - User Guide](tutorial/index.md){.internal-link target=_blank}.

```

Mas se o cliente faz uma requisição para `http://example.com/items/bar` (ou seja, um não existente `item_id "bar"`), esse cliente receberá um HTTP status code 404 (o erro "não encontrado" — *not found error*), e uma resposta JSON:

```JSON
{
  "detail": "Item not found"
}
```

!!! tip "Dica"
    Quando você lançar um `HTTPException`, você pode passar qualquer valor convertível em JSON como parâmetro de `detail`, e não apenas `str`.

## Create a Pull Request

You can [contribute](contributing.md){.internal-link target=_blank} to the source code with Pull Requests, for example:

* To fix a typo you found on the documentation.
* To share an article, video, or podcast you created or found about FastAPI by <a href="https://github.com/tiangolo/fastapi/edit/master/docs/en/data/external_links.yml" class="external-link" target="_blank">editing this file</a>.