* **Valider des données** : venant de chaque requête :
    * Générant automatiquement des **erreurs** renvoyées au client quand la donnée est invalide.
* **Documenter** l'API avec OpenAPI :
    * ce qui ensuite utilisé par les interfaces utilisateur automatiques de documentation interactive.

    * `datetime` objects.
    * `UUID` objects.
    * Database models.
    * ...and many more.
* Automatic interactive API documentation, including 2 alternative user interfaces:
    * Swagger UI.
    * ReDoc.

---

Coming back to the previous code example, **FastAPI** will:

* Validate that there is an `item_id` in the path for `GET` and `PUT` requests.

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      separable from, or merely link (or bind by name) to the interfaces of,
      the Work and Derivative Works thereof.

      "Contribution" shall mean any work of authorship, including
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      separable from, or merely link (or bind by name) to the interfaces of,
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      "Contribution" shall mean any work of authorship, including
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        assertEquals("Second payload should be AnotherTestPayload", AnotherTestPayload.class, multiAnnotation.payload()[1]);
    }

    // Additional test interfaces for multiple groups/payloads test
    private interface AnotherTestGroup {
    }

    private static class AnotherTestPayload implements Payload {
    }

    // Helper methods to get default values

   *
   * <p>Java 8 introduced a new method {@code getAnnotatedBounds()} in the {@link TypeVariable}
   * interface, whose return type {@code AnnotatedType[]} is also new in Java 8. As of 2025, Android
   * has not added {@link AnnotatedType}. That means that we cannot implement that interface in
   * source code in a way that will compile on both Java and Android. If we include the {@code

Além disso, **clientes gerados automaticamente** terão interfaces mais simples, para que os desenvolvedores que se comunicam com sua API possam ter uma experiência muito melhor trabalhando com sua API. 😎

///

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in Source Code form that contains any contents of the Program. Modified
Works shall not include works that contain only declarations,
interfaces, types, classes, structures, or files of the Program solely
in each case in order to link to, bind by name, or subclass the Program
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