# Alternatives, Inspiration and Comparisons

What inspired **FastAPI**, how it compares to alternatives and what it learned from them.

## Intro

**FastAPI** wouldn't exist if not for the previous work of others.

There have been many tools created before that have helped inspire its creation.

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-01-swagger-ui-simple.png)

### Alternative API docs

And now, go to <a href="http://127.0.0.1:8000/redoc" class="external-link" target="_blank">http://127.0.0.1:8000/redoc</a>.

You will see the alternative automatic documentation (provided by <a href="https://github.com/Rebilly/ReDoc" class="external-link" target="_blank">ReDoc</a>):

This is the default response used in **FastAPI**, as you read above.

### `ORJSONResponse`

A fast alternative JSON response using <a href="https://github.com/ijl/orjson" class="external-link" target="_blank">`orjson`</a>, as you read above.

### `UJSONResponse`

An alternative JSON response using <a href="https://github.com/ultrajson/ultrajson" class="external-link" target="_blank">`ujson`</a>.

!!! warning

## Nützliche Standards. Alternative Dokumentation

Und weil das generierte Schema vom <a href="https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.1.0.md" class="external-link" target="_blank">OpenAPI</a>-Standard kommt, gibt es viele kompatible Tools.

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-01-swagger-ui-simple.png)

### Alternative API-Dokumentation

Gehen Sie jetzt auf <a href="http://127.0.0.1:8000/redoc" class="external-link" target="_blank">http://127.0.0.1:8000/redoc</a>.

Sie sehen die alternative automatische Dokumentation (bereitgestellt von <a href="https://github.com/Rebilly/ReDoc" class="external-link" target="_blank">ReDoc</a>):

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-01-swagger-ui-simple.png)

### Alternative API docs

And now, go to <a href="http://127.0.0.1:8000/redoc" class="external-link" target="_blank">http://127.0.0.1:8000/redoc</a>.

You will see the alternative automatic documentation (provided by <a href="https://github.com/Rebilly/ReDoc" class="external-link" target="_blank">ReDoc</a>):

 * might be absent" as two distinct types in your program, which can aid clarity.
 *
 * <p>Some uses of this class include
 *
 * <ul>
 *   <li>As a method return type, as an alternative to returning {@code null} to indicate that no
 *       value was available
 *   <li>To distinguish between "unknown" (for example, not present in a map) and "known to have no

## Les avantages d'avoir une documentation basée sur une norme, et la documentation alternative.

Le schéma généré suivant la norme <a href="https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md" class="external-link" target="_blank">OpenAPI</a>,
il existe de nombreux outils compatibles.

Grâce à cela, **FastAPI** lui-même fournit une documentation alternative (utilisant ReDoc), qui peut être lue

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-01-swagger-ui-simple.png)

### Alternative API docs

And now, go to <a href="http://127.0.0.1:8000/redoc" class="external-link" target="_blank">http://127.0.0.1:8000/redoc</a>.

You will see the alternative automatic documentation (provided by <a href="https://github.com/Rebilly/ReDoc" class="external-link" target="_blank">ReDoc</a>):

    "root_path": "/api/v1"
}
```

### Festlegen des `root_path` in der FastAPI-Anwendung

Falls Sie keine Möglichkeit haben, eine Kommandozeilenoption wie `--root-path` oder ähnlich zu übergeben, können Sie als Alternative beim Erstellen Ihrer FastAPI-Anwendung den Parameter `root_path` setzen:

```Python hl_lines="3"
{!../../../docs_src/behind_a_proxy/tutorial002.py!}
```