Para crear la *path operation* del callback usa el mismo `APIRouter` que creaste arriba.

Debería verse como una *path operation* normal de FastAPI:

* Probablemente debería tener una declaración del body que debería recibir, por ejemplo `body: InvoiceEvent`.
* Y también podría tener una declaración del response que debería devolver, por ejemplo `response_model=InvoiceEventReceived`.

from pydantic import BaseModel, Field

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = Field(
        default=None, title="The description of the item", max_length=300
    )
    price: float = Field(gt=0, description="The price must be greater than zero")
    tax: float | None = None


@app.put("/items/{item_id}")

class ResponseBodyJvmTest {
  @Test
  fun stringEmpty() {
    val body = body("")
    assertThat(body.string()).isEqualTo("")
  }

  @Test
  fun stringLooksLikeBomButTooShort() {
    val body = body("000048")
    assertThat(body.string()).isEqualTo("\u0000\u0000H")
  }

  @Test
  fun stringDefaultsToUtf8() {
    val body = body("68656c6c6f")
    assertThat(body.string()).isEqualTo("hello")
  }

  @Test

from fastapi import Body, FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


class User(BaseModel):
    username: str
    full_name: str | None = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,
    item: Item,
    user: User,

* `Path()`
* `Query()`
* `Header()`
* `Cookie()`
* `Body()`
* `Form()`
* `File()`

Ви також можете задати набір `examples` з додатковою інформацією, яка буде додана до їхніх **JSON-схем** у **OpenAPI**.

### `Body` з `examples`

Тут ми передаємо `examples`, які містять один приклад очікуваних даних у `Body()`:

{* ../../docs_src/schema_extra_example/tutorial003_an_py310.py hl[22:29] *}

        Elements bodyContent = document.body().children().remove();
        document.body().prepend("<div class='container'/>");
        document.body().children().get(0).html(bodyContent.outerHtml());
    }

    private void addTOC(Document document) {

from fastapi import Body, FastAPI
from pydantic import BaseModel

app = FastAPI()


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


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,
    item: Annotated[
        Item,
        Body(
            examples=[
                {

  @Throws(IOException::class)
  fun non101RetainsBody() {
    webServer.enqueue(
      MockResponse
        .Builder()
        .code(200)
        .body("Body")
        .build(),
    )
    newWebSocket()
    clientListener.assertFailure(
      200,
      "Body",
      ProtocolException::class.java,
      "Expected HTTP 101 response but was '200 OK'",
    )
  }

  @Test
  @Throws(IOException::class)

from typing import Union

from fastapi import Body, FastAPI
from pydantic import BaseModel

app = FastAPI()


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


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item = Body(embed=True)):
    results = {"item_id": item_id, "item": item}

Mas por causa das nossas mudanças em `GzipRequest.body`, o corpo da requisição será automaticamente descomprimido quando for carregado pelo **FastAPI** quando necessário.

## Acessando o corpo da requisição em um manipulador de exceção { #accessing-the-request-body-in-an-exception-handler }

/// tip | Dica