Alternatively, you can perform the same steps that scripts does manually.

    Go into the language directory, for the Spanish translations it's at `docs/es/`:

    ```console
    $ cd docs/es/
    ```

    Then run `mkdocs` in that directory:

    ```console
    $ mkdocs serve --dev-addr 8008
    ```

You will see the JSON response as:

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

### Interactive API docs

Now go to <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

```Python hl_lines="6-7"
{!../../../docs_src/path_params/tutorial001.py!}
```

The value of the path parameter `item_id` will be passed to your function as the argument `item_id`.

So, if you run this example and go to <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a>, you will see a response of:

```JSON
{"item_id":"foo"}
```

## Path parameters with types

### About `root_path`

Keep in mind that the server (Uvicorn) won't use that `root_path` for anything else than passing it to the app.

But if you go with your browser to <a href="http://127.0.0.1:8000" class="external-link" target="_blank">http://127.0.0.1:8000/app</a> you will see the normal response:

```JSON
{
    "message": "Hello World",
    "root_path": "/api/v1"

* Python <a href="https://github.com/tiangolo/fastapi" class="external-link" target="_blank">**FastAPI**</a>-Backend:
    * **Schnell**: Sehr hohe Leistung, auf Augenhöhe mit **NodeJS** und **Go** (dank Starlette und Pydantic).
    * **Intuitiv**: Hervorragende Editor-Unterstützung. <abbr title="Auch bekannt als automatische Vervollständigung, IntelliSense">Codevervollständigung</abbr> überall. Weniger Zeitaufwand für das Debuggen.

<div class="termy">

```console
$ uvicorn main:app --reload

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

## Check it

Go to the interactive docs at: <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

You will see something like this:

<img src="/img/tutorial/security/image01.png">

```

</div>

That would work for most of the cases. 😎

You could use that command for example to start your **FastAPI** app in a container, in a server, etc.

## ASGI Servers

Let's go a little deeper into the details.

FastAPI uses a standard for building Python web frameworks and servers called <abbr title="Asynchronous Server Gateway Interface">ASGI</abbr>. FastAPI is an ASGI web framework.

    ```

Notice that the *path operations* define the models they use for request payload and response payload, using the models `Item` and `ResponseMessage`.

### API Docs

If you go to the API docs, you will see that it has the **schemas** for the data to be sent in requests and received in responses:

<img src="/img/tutorial/generate-clients/image01.png">

* Hiệu năng thực sự ấn tượng. Nó là <a href="https://github.com/encode/starlette#performance" class="external-link" target="_blank">một trong nhưng framework Python nhanh nhất, khi so sánh với **NodeJS** và **Go**</a>.
* Hỗ trợ **WebSocket**.
* In-process background tasks.
* Startup and shutdown events.
* Client cho kiểm thử xây dựng trên HTTPX.
* **CORS**, GZip, Static Files, Streaming responses.

---

FastAPI to nowoczesny, wydajny framework webowy do budowania API z użyciem Pythona bazujący na standardowym typowaniu Pythona.

Kluczowe cechy:

* **Wydajność**: FastAPI jest bardzo wydajny, na równi z **NodeJS** oraz **Go** (dzięki Starlette i Pydantic). [Jeden z najszybszych dostępnych frameworków Pythonowych](#wydajnosc).
* **Szybkość kodowania**: Przyśpiesza szybkość pisania nowych funkcjonalności o około 200% do 300%. *