In diesem Fall schreibt die Taskfunktion in eine Datei (den Versand einer E-Mail simulierend).

Und da der Schreibvorgang nicht `async` und `await` verwendet, definieren wir die Funktion mit normalem `def`:

{* ../../docs_src/background_tasks/tutorial001_py310.py hl[6:9] *}

## Den Hintergrundtask hinzufügen { #add-the-background-task }

#### Http2Stream

This lock guards the internal state of each stream. As above, it is never held for blocking operations. When we need to hold an application thread to block a read, we use wait/notify on this lock. This works because the lock is released while `wait()` is waiting.

#### Http2Writer

            crawler.getCrawlerContext().setMaxAccessCount(maxCount);
            crawler.getCrawlerContext().setNumOfThread(numOfThread);
            final String sessionId = crawler.execute();

            // Wait for crawler to start running with polling
            long startTime = System.currentTimeMillis();
            while (crawler.crawlerContext.getStatus() != CrawlerStatus.RUNNING && System.currentTimeMillis() - startTime < 5000) {

```Python
with open("file.txt") as file:
    file.read()
```

Python 的最近几个版本也有了一个**异步上下文管理器**，你可以通过 `async with` 来使用：

```Python
async with lifespan(app):
    await do_stuff()
```

你可以像上面一样创建一个上下文管理器或者异步上下文管理器，它的作用是在进入 `with` 块时，执行 `yield` 之前的代码，并且在离开 `with` 块时，执行 `yield` 后面的代码。

但在我们上面的例子里，我们并不是直接使用，而是传递给 FastAPI 来供其使用。

@REM
@REM   JAVA_HOME           (Optional) Points to a Java installation.
@REM   MAVEN_BATCH_ECHO    (Optional) Set to 'on' to enable the echoing of the batch commands.
@REM   MAVEN_BATCH_PAUSE   (Optional) set to 'on' to wait for a key stroke before ending.
@REM   MAVEN_OPTS          (Optional) Java runtime options used when Maven is executed.
@REM   MAVEN_SKIP_RC       (Optional) Flag to disable loading of mavenrc files.

# This script will not and should not be executed in the self hosted runner

echo "script failed" >resiliency-initial.log # assume initial state

echo "sleep to wait for MinIO Server to be ready prior mc commands"
# https://github.com/minio/mc/issues/3599

MINIO_SERVER_URL="http://127.0.0.1:9000"
ALIAS_NAME=myminio
BUCKET="test-bucket"
SRC_DIR="/tmp/data"
INLINED_DIR="/tmp/inlined"

            // Test implementation
        }

        public boolean waitForNotification(long timeoutMs) throws InterruptedException {
            return notificationLatch.await(timeoutMs, TimeUnit.MILLISECONDS);
        }

        public WitnessNotification getLastNotification() {
            return lastNotification;
        }
    }

    /**

## 创建一个任务函数 { #create-a-task-function }

创建要作为后台任务运行的函数。

它只是一个可以接收参数的标准函数。

它可以是 `async def` 或普通的 `def` 函数，**FastAPI** 知道如何正确处理。

在这种情况下，任务函数将写入一个文件（模拟发送电子邮件）。

由于写操作不使用 `async` 和 `await`，我们用普通的 `def` 定义函数：

{* ../../docs_src/background_tasks/tutorial001_py310.py hl[6:9] *}

## 添加后台任务 { #add-the-background-task }

在你的 *路径操作函数* 里，用 `.add_task()` 方法将任务函数传到 *后台任务* 对象中：

MC_CONFIG_DIR="{{ .Values.configPathmc }}"
MC="/usr/bin/mc --insecure --config-dir ${MC_CONFIG_DIR}"
{{- else }}
MC="/usr/bin/mc --insecure"
{{- end }}

# connectToMinio
# Use a check-sleep-check loop to wait for MinIO service to be available
connectToMinio() {
  SCHEME=$1
  ATTEMPTS=0 ; LIMIT=29 ; # Allow 30 attempts
  set -e ; # fail if we can't read the keys.

            super.process(consumer);
            latch.countDown();
        }

        @Override
        public void waitForProcessed() throws InterruptedException {
            latch.await();
        }
    }