}
		if b == ';' { // separating character
			break
		}

		// Manually deserialize the size since AWS specified
		// the chunk size to be of variable width. In particular,
		// a size of 16 is encoded as `10` while a size of 64 KB
		// is `10000`.
		switch {
		case b >= '0' && b <= '9':
			size = size<<4 | int(b-'0')
		case b >= 'a' && b <= 'f':
			size = size<<4 | int(b-('a'-10))

from datetime import datetime

from fastapi import FastAPI
from fastapi.encoders import jsonable_encoder
from fastapi.responses import JSONResponse
from pydantic import BaseModel


class Item(BaseModel):
    title: str
    timestamp: datetime
    description: str | None = None


app = FastAPI()


@app.put("/items/{id}")
def update_item(id: str, item: Item):
    json_compatible_item_data = jsonable_encoder(item)

/**
 * The first two bytes of each value is a header that includes its tag (field ID) and length.
 */
internal data class DerHeader(
  /**
   * Namespace of the tag.
   *
   * This value is encoded in bits 7 and 8 of the first byte of each value.
   *
   * ```
   * 0b00xxxxxx Universal
   * 0b01xxxxxx Application
   * 0b10xxxxxx Context-Specific
   * 0b11xxxxxx Private
   * ```
   */
  var tagClass: Int,

## Herhangi Bir Veriyi JSON Uyumlu Hale Getirme

Herhangi bir veriyi JSON uyumlu hale getirmek için, [Tutorial - JSON Compatible Encoder](../tutorial/encoder.md){.internal-link target=_blank} sayfasını okuyun.

## OpenAPI Meta Verileri - Dokümantasyon

По умолчанию **FastAPI** автоматически преобразует возвращаемое значение в JSON с помощью `jsonable_encoder`, как описано в [JSON кодировщик](../tutorial/encoder.md){.internal-link target=_blank}.

Затем "под капотом" эти данные, совместимые с JSON (например `dict`), помещаются в `JSONResponse`, который используется для отправки ответа клиенту.

  private val bytesIn = Buffer()
  private val hpackReader = Hpack.Reader(bytesIn, 4096)

  protected fun testDecoder(story: Story) {
    for (testCase in story.cases) {
      val encoded = testCase.wire ?: continue
      bytesIn.write(encoded)
      hpackReader.readHeaders()
      assertSetEquals(
        "seqno=$testCase.seqno",
        testCase.headersList,
        hpackReader.getAndResetHeaderList(),
      )
    }
  }

    @Override
    protected SortedMap<String, String> delegate() {
      return delegate;
    }
  }

  private static String encode(String str) {
    return BaseEncoding.base64().encode(str.getBytes(UTF_8));
  }

  private static final Function<String, String> DECODE_FUNCTION =
      new Function<String, String>() {
        @Override

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3.tls.internal.der

import okio.Buffer
import okio.ByteString

/**
 * Encode and decode a model object like a [Long] or [Certificate] as DER bytes.
 */
internal interface DerAdapter<T> {
  /** Returns true if this adapter can read [header] in a choice. */
  fun matches(header: DerHeader): Boolean

from typing import Union

from fastapi import FastAPI
from fastapi.encoders import jsonable_encoder
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: Union[str, None] = None
    description: Union[str, None] = None
    price: Union[float, None] = None
    tax: float = 10.5
    tags: list[str] = []


items = {
    "foo": {"name": "Foo", "price": 50.2},

**FastAPI** will make sure to read that data from the right place instead of JSON.

/// note | Technical Details

Data from forms is normally encoded using the "media type" `application/x-www-form-urlencoded` when it doesn't include files.

But when the form includes files, it is encoded as `multipart/form-data`. If you use `File`, **FastAPI** will know it has to get the files from the correct part of the body.