# Background Tasks

You can define background tasks to be run *after* returning a response.

This is useful for operations that need to happen after a request, but that the client doesn't really have to be waiting for the operation to complete before receiving the response.

This includes, for example:

* Email notifications sent after performing an action:

<font color="#4E9A06">INFO</font>:     Started server process [<font color="#06989A">2265873</font>]
<font color="#4E9A06">INFO</font>:     Waiting for application startup.
<font color="#4E9A06">INFO</font>:     Application startup complete.
```

</div>

`fastapi`라고 불리는 명령어 프로그램은 **FastAPI CLI**입니다.

FastAPI CLI는 Python 프로그램의 경로(예: `main.py`)를 인수로 받아, `FastAPI` 인스턴스(일반적으로 `app`으로 명명)를 자동으로 감지하고 올바른 임포트 과정을 결정한 후 이를 실행합니다.

	echo "verified sitea-> COMPLETED, siteb-> REPLICA"
fi

if diff -pruN <(./mc stat --no-list --json sitea/bucket/hosts | jq .) <(./mc stat --no-list --json sitec/bucket/hosts | jq .) | grep -q 'COMPLETED\|REPLICA'; then
	echo "verified sitea-> COMPLETED, sitec-> REPLICA"
fi

    computingLatch.countDown();
    // don't check cache.size() until we know the get("b") call is complete
    computationComplete.await();

    // At this point, the listener should be holding the seed value (a -> a), and the map should
    // contain the computed value (b -> b), since the clear() happened before the computation
    // completed.
    assertEquals(1, listener.size());

* **Mniejsza ilość błędów**: Zmniejsza ilość ludzkich (dewelopera) błędy o około 40%. *
* **Intuicyjność**: Wspaniałe wsparcie dla edytorów kodu. Dostępne wszędzie <abbr title="znane jako auto-complete, autocompletion, IntelliSense">automatyczne uzupełnianie</abbr> kodu. Krótszy czas debugowania.
* **Łatwość**: Zaprojektowany by być prosty i łatwy do nauczenia. Mniej czasu spędzonego na czytanie dokumentacji.

      redundantOpCount >= lruEntries.size
  }

  /**
   * Drops the entry for [key] if it exists and can be removed. If the entry for [key] is currently
   * being edited, that edit will complete normally but its value will not be stored.
   *
   * @return true if an entry was removed.
   */
  @Synchronized
  @Throws(IOException::class)
  fun remove(key: String): Boolean {
    initialize()

<font color="#4E9A06">INFO</font>:     Started server process [<font color="#06989A">2265873</font>]
<font color="#4E9A06">INFO</font>:     Waiting for application startup.
<font color="#4E9A06">INFO</font>:     Application startup complete.
```

</div>

该命令行程序 `fastapi` 就是 **FastAPI CLI**。

FastAPI CLI 接收你的 Python 程序路径，自动检测包含 FastAPI 的变量（通常命名为 `app`）及其导入方式，然后启动服务。

在生产环境中，你应该使用 `fastapi run` 命令。🚀

<font color="#4E9A06">INFO</font>:     Started server process [<font color="#06989A">2306215</font>]
<font color="#4E9A06">INFO</font>:     Waiting for application startup.
<font color="#4E9A06">INFO</font>:     Application startup complete.
<font color="#4E9A06">INFO</font>:     Uvicorn running on <b>http://0.0.0.0:8000</b> (Press CTRL+C to quit)
```

</div>

That would work for most of the cases. 😎

			staleWriters[i] = newBitrotWriter(disk, "", "testbucket", "testobject", erasure.ShardFileSize(test.size), test.algorithm, erasure.ShardSize())
		}

		// test case setup is complete - now call Heal()
		err = erasure.Heal(context.Background(), staleWriters, readers, test.size, nil)
		closeBitrotReaders(readers)
		closeBitrotWriters(staleWriters)
		if err != nil && !test.shouldFail {

    } else {
      timeout().deadlineNanoTime(nowNs + originalDurationNs)
    }
  }
}

/**
 * Attempts to exhaust this, returning true if successful. This is useful when reading a complete
 * source is helpful, such as when doing so completes a cache body or frees a socket connection for
 * reuse.
 */
internal fun Source.discard(
  timeout: Int,
  timeUnit: TimeUnit,
): Boolean =
  try {