## Data validation

But if you go to the browser at <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 nice HTTP error of:

```JSON
{
  "detail": [
    {
      "type": "int_parsing",
      "loc": [
        "path",
        "item_id"
      ],

import okhttp3.MediaType
import okhttp3.MediaType.Companion.toMediaTypeOrNull
import okhttp3.ResponseBody
import okio.BufferedSource

class RealResponseBody(
  /**
   * Use a string to avoid parsing the content type until needed. This also defers problems caused
   * by malformed content types.
   */
  private val contentTypeString: String?,
  private val contentLength: Long,
  private val source: BufferedSource,

    Ceci vous permettra d'obtenir des fonctionnalités de l'éditeur dans votre fonction, telles
    que des vérifications d'erreur, de l'auto-complétion, etc.

## <abbr title="aussi appelé sérialisation, ou parfois parsing ou marshalling en anglais">Conversion</abbr> de données

    val c = this[i]
    // The WHATWG Host parsing rules accepts some character codes which are invalid by
    // definition for OkHttp's host header checks (and the WHATWG Host syntax definition). Here
    // we rule out characters that would cause problems in host headers.
    if (c <= '\u001f' || c >= '\u007f') {
      return true
    }
    // Check for the characters mentioned in the WHATWG Host parsing spec:

    private val KNOWN_FAILURES =
      listOf(
        "Parsing: <http://example\t.\norg> against <http://example.org/foo/bar>",
        "Parsing: <http://f:0/c> against <http://example.org/foo/bar>",
        "Parsing: <http://f:00000000000000/c> against <http://example.org/foo/bar>",
        "Parsing: <http://f:\n/c> against <http://example.org/foo/bar>",
        "Parsing: <http://f:999999/c> against <http://example.org/foo/bar>",

* <abbr title="anche noto come: serializzazione, parsing, marshalling">Conversione</abbr> dei dati di input: da risorse esterne a dati e tipi di Python. È possibile leggere da:
    * JSON.
    * Path parameters.
    * Query parameters.
    * Cookies.
    * Headers.
    * Form.
    * File.

## Datenvalidierung

Wenn Sie aber im Browser <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a> besuchen, erhalten Sie eine hübsche HTTP-Fehlermeldung:

```JSON
{
  "detail": [
    {
      "type": "int_parsing",
      "loc": [
        "path",
        "item_id"
      ],

* Bemeneti adatok<abbr title="also known as: serialization, parsing, marshalling"> átváltása</abbr> : a hálózatról érkező Python adatokká és típusokká. Adatok olvasása következő forrásokból:
    * JSON.
    * Cím paraméterek.
    * Query paraméterek.
    * Cookie-k.
    * Header-ök.
    * Formok.
    * Fájlok.

* <abbr title="en inglés: serialization, parsing, marshalling">Conversión</abbr> de datos de input: viniendo de la red a datos y tipos de Python. Leyendo desde:
    * JSON.
    * Path parameters.
    * Query parameters.
    * Cookies.
    * Headers.
    * Formularios.
    * Archivos.

    * FastAPI, Starlette'e ek olarak daha fazla özellik sunar. Bunlar veri doğrulama ve <abbr title="Dönüşüm: serialization, parsing, marshalling olarak da biliniyor">dönüşümü</abbr> gibi API'lar oluştururken neredeyse ve her zaman ihtiyaç duyduğunuz özelliklerdir. Ve bunu kullanarak, ücretsiz olarak otomatik dokümantasyon elde edersiniz (otomatik dokümantasyon çalışan uygulamalara...