La `RequestValidationError` contient le `body` qu'elle a reçu avec des données invalides.

Vous pouvez l'utiliser pendant le développement de votre application pour journaliser le corps et le déboguer, le renvoyer à l'utilisateur, etc.

{* ../../docs_src/handling_errors/tutorial005_py310.py hl[14] *}

Essayez maintenant d'envoyer un élément invalide comme :

```JSON

constraints.UriType.message = {item} ma nierozpoznany URI.
constraints.CronExpression.message = {item} nie jest prawidłowym wyrażeniem CRON.

# ----------------------------------------------------------
# Application Exception
# ---------------------
# /- - - - - - - - - - - - - - - - - - - - - - - - - - - - -
# five framework-embedded messages (don't change key names)
# - - - - - - - - - -/

# Déclarer des exemples de données de requête { #declare-request-example-data }

Vous pouvez déclarer des exemples des données que votre application peut recevoir.

Voici plusieurs façons de le faire.

## Ajouter des données JSON Schema supplémentaires dans les modèles Pydantic { #extra-json-schema-data-in-pydantic-models }

Vous pouvez déclarer `examples` pour un modèle Pydantic qui seront ajoutés au JSON Schema généré.

   * leaking resources callers must [close the response body][ResponseBody] or the response.
   *
   * Note that transport-layer success (receiving a HTTP response code, headers and body) does not
   * necessarily indicate application-layer success: `response` may still indicate an unhappy HTTP
   * response code like 404 or 500.
   *
   * @throws IOException if the request could not be executed due to cancellation, a connectivity

Events
======

Events allow you to capture metrics on your application’s HTTP calls. Use events to monitor:

 * The size and frequency of the HTTP calls your application makes. If you’re making too many calls, or your calls are too large, you should know about it!
 * The performance of these calls on the underlying network. If the network’s performance isn’t sufficient, you need to either improve the network or use less of it.

### EventListener

                "responses": {
                    "200": {
                        "description": "Successful Response",
                        "content": {
                            "application/json": {
                                "schema": {}
                            }
                        }
                    }
                },
                "x-aperture-labs-portal": "blue"

Uygulama kapanırken çalıştırılacak bir fonksiyon eklemek için, `"shutdown"` event’i ile tanımlayın:

{* ../../docs_src/events/tutorial002_py310.py hl[6] *}

Burada `shutdown` event handler fonksiyonu, `log.txt` dosyasına `"Application shutdown"` satırını yazar.

/// info | Bilgi

`open()` fonksiyonunda `mode="a"` "append" anlamına gelir; yani satır, önceki içeriği silmeden dosyada ne varsa onun sonuna eklenir.

///

/// tip | İpucu

You can use the Select API to query objects with following features:

- Objects must be in CSV, JSON, or Parquet(*) format.

          + "@:"; // The gendelim characters permitted in paths.

  /**
   * Returns an {@link Escaper} instance that escapes strings so they can be safely included in <a
   * href="https://url.spec.whatwg.org/#application-x-www-form-urlencoded-percent-encode-set">URL
   * form parameter names and values</a>. Escaping is performed with the UTF-8 character encoding.
   * The caller is responsible for <a

Вспомогательные дополнительные функции `fake_password_hasher` и `fake_save_user` используются только для демонстрации возможного потока данных и, конечно, не обеспечивают настоящую безопасность.

///

## Сократите дублирование { #reduce-duplication }

Сокращение дублирования кода — это одна из главных идей **FastAPI**.