# Зависимости с yield

FastAPI поддерживает зависимости, которые выполняют некоторые <abbr title='также известные как "exit", "cleanup", "teardown", "close", "context managers", ...'>дополнительные действия после завершения работы</abbr>.

Для этого используйте `yield` вместо `return`, а дополнительный код напишите после него.

/// tip | Подсказка

Обязательно используйте `yield` один-единственный раз.

///

/// note | Технические детали

# yieldを持つ依存関係

FastAPIは、いくつかの<abbr title='時々"exit"、"cleanup"、"teardown"、"close"、"context managers"、 ...のように呼ばれる'>終了後の追加のステップ</abbr>を行う依存関係をサポートしています。

これを行うには、`return`の代わりに`yield`を使い、その後に追加のステップを書きます。

/// tip | 豆知識

`yield`は必ず一度だけ使用するようにしてください。

///

/// info | 情報

これを動作させるには、**Python 3.7** 以上を使用するか、**Python 3.6** では"backports"をインストールする必要があります:

```
pip install async-exit-stack async-generator
```

    return clientTestRule
  }

  @BeforeEach
  fun setUp() {
    platform.assumeNotOpenJSSE()
  }

  @AfterEach
  @Throws(InterruptedException::class)
  fun tearDown() {
    clientListener.assertExhausted()
  }

  @Test
  fun textMessage() {
    webServer.enqueue(
      MockResponse
        .Builder()
        .webSocketUpgrade(serverListener)

# Dependencies with yield { #dependencies-with-yield }

FastAPI supports dependencies that do some <abbr title='sometimes also called "exit code", "cleanup code", "teardown code", "closing code", "context manager exit code", etc.'>extra steps after finishing</abbr>.

To do this, use `yield` instead of `return`, and write the extra steps (code) after.

/// tip

Make sure to use `yield` one single time per dependency.

///

/// note | Technical Details

    call =
      clientTestRule.newClient().newCall(
        Request
          .Builder()
          .url("https://$uriHost:$uriPort/")
          .build(),
      ) as RealCall
  }

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

  @Test fun singleRoute() {
    val address = factory.newAddress()
    val routeSelector = newRouteSelector(address)
    assertThat(routeSelector.hasNext()).isTrue()

      listener.onClosed(this, code, reason!!)
    }

    readerToClose?.closeQuietly()
  }

  /** For testing: force this web socket to release its threads. */
  @Throws(InterruptedException::class)
  fun tearDown() {
    taskQueue.shutdown()
    taskQueue.idleLatch().await(10, TimeUnit.SECONDS)
  }

  @Synchronized fun sentPingCount(): Int = sentPingCount

      .build()
  private val executorService = Executors.newScheduledThreadPool(1)

  @BeforeEach
  fun setUp() {
    platform.assumeNotOpenJSSE()
    platform.assumeHttp2Support()
  }

  @AfterEach
  fun tearDown() {
    executorService.shutdown()
  }

  @Test
  @Throws(IOException::class)
  fun http1DoesntSupportDuplex() {
    val call =
      client.newCall(
        Request
          .Builder()

# Dependências com yield

O FastAPI possui suporte para dependências que realizam <abbr title='também chamados de "código de saída", "código de cleanup", "código de teardown", "código de finalização", "código de saída para gerenciador de contextos", etc.'>alguns passos extras ao finalizar</abbr>.

Para fazer isso, utilize `yield` em vez de `return`, e escreva os passos extras (código) depois.

/// tip | Dica

Garanta que `yield` é utilizado apenas uma vez.

@Tag("Slow")
class MockWebServerTest {
  @RegisterExtension
  var platform = PlatformRule()
  private val server = MockWebServer()

  @BeforeEach
  fun setUp() {
    server.start()
  }

  @AfterEach
  fun tearDown() {
    server.shutdown()
  }

  @Test
  fun defaultMockResponse() {
    val response = MockResponse()
    assertThat(headersToList(response)).containsExactly("Content-Length: 0")

   */
  private val routePlanner = FakeRoutePlanner(taskFaker = taskFaker)
  private val finder = FastFallbackExchangeFinder(routePlanner, taskRunner)

  @AfterEach
  fun tearDown() {
    taskFaker.close()
    routePlanner.close()
  }

  @Test
  fun takeConnectedConnection() {
    val plan0 = routePlanner.addPlan()
    plan0.connectState = TLS_CONNECTED