}

  @Test
  fun testRedirectsDoNotIncludeTooManyCookies() {
    val redirectTarget = MockWebServer()
    redirectTarget.enqueue(MockResponse.Builder().body("A").build())
    redirectTarget.start()
    val redirectTargetUrl = urlWithIpAddress(redirectTarget, "/")
    val redirectSource = MockWebServer()
    redirectSource.enqueue(
      MockResponse
        .Builder()

首先，新建包含一些用于回调的 `APIRouter`。

{* ../../docs_src/openapi_callbacks/tutorial001.py hl[5,26] *}

### 创建回调*路径操作*

创建回调*路径操作*也使用之前创建的 `APIRouter`。

它看起来和常规 FastAPI *路径操作*差不多：

* 声明要接收的请求体，例如，`body: InvoiceEvent`
* 还要声明要返回的响应，例如，`response_model=InvoiceEventReceived`

{* ../../docs_src/openapi_callbacks/tutorial001.py hl[17:19,22:23,29:33] *}

回调*路径操作*与常规*路径操作*有两点主要区别：

    - 如果驗證失敗，將會返回清楚有用的錯誤訊息。
- 查看 `GET` 請求中是否有命名為 `q` 的查詢參數 (例如 `http://127.0.0.1:8000/items/foo?q=somequery`)。
    - 因為 `q` 參數被宣告為 `= None`，所以是選填的。
    - 如果沒有宣告 `None`，則此參數將會是必填 (例如 `PUT` 範例的請求 body)。
- 對於 `PUT` 的請求 `/items/{item_id}`，將會讀取 body 為 JSON：
    - 驗證是否有必填屬性 `name` 且型別是 `str`。
    - 驗證是否有必填屬性 `price` 且型別是 `float`。
    - 驗證是否有選填屬性 `is_offer` 且型別是 `bool`。
    - 以上驗證都適用於多層次巢狀 JSON 物件。
- 自動轉換 JSON 格式。

  @StartStop
  private val server = MockWebServer()

  @AfterEach fun tearDown() {
    httpClient.close()
  }

  @Test fun get() {
    server.enqueue(
      MockResponse
        .Builder()
        .body("hello, Apache HttpClient 5.x")
        .build(),
    )

    val request = HttpGet(server.url("/").toUri())
    request.addHeader("Accept", "text/plain")

    httpClient.execute(request).use { response ->

    assert response.status_code == 422
    assert response.json() == {
        "detail": [
            {
                "type": "string_pattern_mismatch",
                "loc": ["body", "q"],
                "msg": "String should match pattern '^fixedquery$'",
                "input": "nonregexquery",
                "ctx": {"pattern": "^fixedquery$"},
            }
        ]
    }

        .build()

    client.newCall(request).execute().use { response ->
      if (!response.isSuccessful) throw IOException("Unexpected code $response")

      println(response.body.string())
    }
  }
}

object ConsoleCallbackHandler : CallbackHandler {
  override fun handle(callbacks: Array<Callback>) {
    for (callback in callbacks) {
      if (callback is PasswordCallback) {

The same way you use `Body`, `Query`, etc. with your *path operation function* parameters, use `Depends` with a new parameter:

{* ../../docs_src/dependencies/tutorial001_an_py310.py hl[13,18] *}

Although you use `Depends` in the parameters of your function the same way you use `Body`, `Query`, etc, `Depends` works a bit differently.

You only give `Depends` a single parameter.

They will receive an error response telling them that the field `extra` is not allowed:

```json
{
    "detail": [
        {
            "type": "extra_forbidden",
            "loc": ["body", "extra"],
            "msg": "Extra inputs are not permitted",
            "input": "Mr. Poopybutthole"
        }
    ]
}
```

## Summary { #summary }

//
// When **no** flags are passed, the behavior is to trace both headers and body,
// gzip the response and throttle the handler via `maxClients`. Each of these
// can be disabled via the corresponding `s3HFlag`.
//
// CAUTION: for requests involving large req/resp bodies ensure to pass the
// `traceHdrsS3HFlag`, otherwise both headers and body will be traced, causing
// high memory usage!

{* ../../docs_src/request_files/tutorial001_an_py39.py hl[3] *}

## Definir Parámetros `File` { #define-file-parameters }

Crea parámetros de archivo de la misma manera que lo harías para `Body` o `Form`:

{* ../../docs_src/request_files/tutorial001_an_py39.py hl[9] *}

/// info | Información

`File` es una clase que hereda directamente de `Form`.