![ReDoc](https://fastapi.tiangolo.com/img/index/index-02-redoc-simple.png)

## Example upgrade

Now modify the file `main.py` to receive a body from a `PUT` request.

Declare the body using standard Python types, thanks to Pydantic.

```Python hl_lines="4  9-12  25-27"
from typing import Union

from fastapi import FastAPI
from pydantic import BaseModel

    server.enqueue(
      MockResponse.Builder()
        .body("seed connection")
        .build(),
    )
    server.enqueue(
      MockResponse.Builder()
        .code(421)
        .body("misdirected!")
        .build(),
    )
    server.enqueue(
      MockResponse.Builder()
        .body("after misdirect")
        .build(),
    )

    // Seed the connection pool.

    inputStream.close()
  }

  @Test
  fun disconnectRequestHalfway() {
    server.enqueue(MockResponse().setSocketPolicy(SocketPolicy.DISCONNECT_DURING_REQUEST_BODY))
    // Limit the size of the request body that the server holds in memory to an arbitrary
    // 3.5 MBytes so this test can pass on devices with little memory.
    server.bodyLimit = 7 * 512 * 1024

!!! warning
    You can declare multiple `File` and `Form` parameters in a *path operation*, but you can't also declare `Body` fields that you expect to receive as JSON, as the request will have the body encoded using `multipart/form-data` instead of `application/json`.

    This is not a limitation of **FastAPI**, it's part of the HTTP protocol.

## Optional File Upload

  // the call, but they may be accessed by other threads for duplex requests.

  /** True if this call still has a request body open. */
  private var requestBodyOpen = false

  /** True if this call still has a response body open. */
  private var responseBodyOpen = false

  /** True if there are more exchanges expected for this call. */
  private var expectMoreExchanges = true

        generateReadmeFragment(templateFolder, "common-body", settings, comments, descriptor, projectLayoutSetupRegistry)
        generateReadmeFragment(templateFolder, "$specificContentId-body", settings, comments, descriptor, projectLayoutSetupRegistry)
        if (descriptor.language === Language.JAVA && descriptor.componentType === ComponentType.LIBRARY) {

![ReDoc](https://fastapi.tiangolo.com/img/index/index-02-redoc-simple.png)

## Nâng cấp ví dụ

Bây giờ sửa tệp tin `main.py` để nhận body từ một request `PUT`.

Định nghĩa của body sử dụng kiểu dữ liệu chuẩn của Python, cảm ơn Pydantic.

```Python hl_lines="4  9-12  25-27"
from typing import Union

from fastapi import FastAPI
from pydantic import BaseModel

!!! warning "Achtung"
    Sie können mehrere `File`- und `Form`-Parameter in einer *Pfadoperation* deklarieren, aber Sie können nicht gleichzeitig auch `Body`-Felder deklarieren, welche Sie als JSON erwarten, da der Request den Body mittels `multipart/form-data` statt `application/json` kodiert.

    Das ist keine Limitation von **FastAPI**, sondern Teil des HTTP-Protokolls.

## Optionaler Datei-Upload

    ```kotlin
    val response: Response = call.execute()
    val multipartReader = MultipartReader(response.body!!)

    multipartReader.use {
      while (true) {
        val part = multipartReader.nextPart() ?: break
        process(part.headers, part.body)
      }
    }
    ```

 *  New: `MediaType.parameter()` gets a parameter like `boundary` from a media type like

![ReDoc](https://fastapi.tiangolo.com/img/index/index-02-redoc-simple.png)

## Example upgrade

Now modify the file `main.py` to receive a body from a `PUT` request.

Declare the body using standard Python types, thanks to Pydantic.

```Python hl_lines="4  9-12  25-27"
from typing import Union

from fastapi import FastAPI
from pydantic import BaseModel