assertThat(sendPingFrame(true, expectedPayload1, expectedPayload2)).isEqualTo(frame)
    reader.nextFrame(
      requireSettings = false,
      object : BaseTestHandler() {
        override fun ping(
          ack: Boolean,
          payload1: Int,
          payload2: Int,
        ) {
          assertThat(ack).isTrue()
          assertThat(payload1).isEqualTo(expectedPayload1)

        String field = settings.array().get(SuggestSettings.DefaultKeys.SUPPORTED_FIELDS)[0];

        Map<String, Object> document = new HashMap<>();
        document.put(field, "Sing the Supercalifragilisticexpialidocious for Honorificabilitudinitatibus");
        suggester.indexer().indexFromDocument(new Map[] { document });
        suggester.refresh();

You just pass it to `Depends` and **FastAPI** knows how to do the rest.

///

## Share `Annotated` dependencies { #share-annotated-dependencies }

In the examples above, you see that there's a tiny bit of **code duplication**.

When you need to use the `common_parameters()` dependency, you have to write the whole parameter with the type annotation and `Depends()`:

```Python

    }

    /**
     * Gets the cookie remember-me key for persistent login.
     * Currently returns empty as remember-me functionality is not enabled.
     *
     * @return an optional thing containing the remember-me key, or empty if not configured
     */
    @Override
    protected OptionalThing<String> getCookieRememberMeKey() {
        // example to use remember-me

                return true; // Continue processing
            });
        } catch (Exception e) {
            // Expected in test environment without proper SearchEngineClient
            // The important thing is that the method exists and accepts the correct parameters
        }

        // Verify that the scroll method exists with correct signature
        try {

  }

  companion object {
    @JvmOverloads
    fun body(
      hex: String,
      charset: String? = null,
    ): ResponseBody {
      val mediaType = if (charset == null) null else "any/thing; charset=$charset".toMediaType()
      return hex.decodeHex().toResponseBody(mediaType)
    }

    fun exhaust(reader: Reader): String {
      val builder = StringBuilder()
      val buf = CharArray(10)

Let's say you want it to return indented and formatted JSON, so you want to use the orjson option `orjson.OPT_INDENT_2`.

You could create a `CustomORJSONResponse`. The main thing you have to do is create a `Response.render(content)` method that returns the content as `bytes`:

{* ../../docs_src/custom_response/tutorial009c_py310.py hl[9:14,17] *}

Now instead of returning:

```json

	}
	t.Logf("response: %v", err)

	// Check that remote is canceled.
	<-serverCanceled
	close(nowBlocking)
}

// testServerStreamPingRunning will test if server and client handle ping even when blocked.
func testServerStreamPingRunning(t *testing.T, local, remote *Manager, inCap int, blockResp, blockReq bool) {
	defer testlogger.T.SetErrorTB(t)()
	errFatal := func(err error) {
		t.Helper()

{* ../../docs_src/openapi_callbacks/tutorial001_py310.py hl[7:11,34:51] *}

/// tip

The `callback_url` query parameter uses a Pydantic [Url](https://docs.pydantic.dev/latest/api/networks/) type.

///

The only new thing is the `callbacks=invoices_callback_router.routes` as an argument to the *path operation decorator*. We'll see what that is next.

## Documenting the callback { #documenting-the-callback }

{* ../../docs_src/server_sent_events/tutorial005_py310.py hl[14] *}

## 技術詳細 { #technical-details }

FastAPI は SSE のいくつかのベストプラクティスを標準で実装しています。

- メッセージがない場合は 15 秒ごとに「キープアライブ」用の `ping` コメントを送信し、一部のプロキシが接続を閉じるのを防ぎます（[HTML 仕様: Server-Sent Events](https://html.spec.whatwg.org/multipage/server-sent-events.html#authoring-notes) の推奨に従います）。
- ストリームの**キャッシュを防止**するため、`Cache-Control: no-cache` ヘッダーを設定します。