///

### 尝试带有依赖项的 WebSockets

如果您的文件名为 `main.py`，请使用以下命令运行应用程序：

```console
$ uvicorn main:app --reload

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

在FastAPI中仍然可以单独使用 `BackgroundTask`，但您必须在代码中创建对象，并返回包含它的Starlette `Response`。

更多细节查看 <a href="https://www.starlette.dev/background/" class="external-link" target="_blank">Starlette's official docs for Background Tasks</a>.

## 告诫

如果您需要执行繁重的后台计算，并且不一定需要由同一进程运行（例如，您不需要共享内存、变量等），那么使用其他更大的工具（如 <a href="https://docs.celeryq.dev" class="external-link" target="_blank">Celery</a>）可能更好。

它们往往需要更复杂的配置，即消息/作业队列管理器，如RabbitMQ或Redis，但它们允许您在多个进程中运行后台任务，甚至是在多个服务器中。

# SQL (관계형) 데이터베이스

**FastAPI**에서 SQL(관계형) 데이터베이스 사용은 필수가 아닙니다. 여러분이 원하는 **어떤 데이터베이스든** 사용할 수 있습니다.

여기서는 <a href="https://sqlmodel.tiangolo.com/" class="external-link" target="_blank">SQLModel</a>을 사용하는 예제를 살펴보겠습니다.

**SQLModel**은 <a href="https://www.sqlalchemy.org/" class="external-link" target="_blank">SQLAlchemy</a>와 Pydantic을 기반으로 구축되었습니다.SQLModel은 **SQL 데이터베이스**를 사용하는 FastAPI 애플리케이션에 완벽히 어울리도록 **FastAPI**의 제작자가 설계한 도구입니다.

/// tip | 팁

///

Führen Sie das Beispiel aus mit:

<div class="termy">

```console
$ fastapi dev main.py

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

</div>

## Es testen { #check-it }

Gehen Sie zu der interaktiven Dokumentation unter: <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>.

but that goroutine may create other goroutines,
which run concurrently.
</p>

<p class="rule">
If a package <code>p</code> imports package <code>q</code>, the completion of
<code>q</code>'s <code>init</code> functions happens before the start of any of <code>p</code>'s.
</p>

<p class="rule">
The completion of all <code>init</code> functions is synchronized before

 *
 * @author shinsuke
 *
 */
public class OpenSearchUrlQueueService extends AbstractCrawlerService implements UrlQueueService<OpenSearchUrlQueue> {
    /**
     * Logger instance.
     */
    private static final Logger logger = LogManager.getLogger(OpenSearchUrlQueueService.class);

    /**
     * Data service for checking access results.
     */
    @Resource

import org.codelibs.fess.crawler.exception.ExtractException;

/**
 * Extracts text content by executing an external command.
 */
public class CommandExtractor extends AbstractExtractor {
    private static final Logger logger = LogManager.getLogger(CommandExtractor.class);

    /** The encoding for the output. */
    protected String outputEncoding = Constants.UTF_8;

    /** The extension for the output file. */

    return false;
  }

  @Override
  public String toString() {
    return asMapOfRanges().toString();
  }

  /**
   * This class is used to serialize ImmutableRangeMap instances. Serializes the {@link
   * #asMapOfRanges()} form.
   */
  private static final class SerializedForm<K extends Comparable<?>, V> implements Serializable {

    private final ImmutableMap<Range<K>, V> mapOfRanges;

 *
 * <p>Most methods in this class treat absent values and zero values identically, as individually
 * documented. Exceptions to this are {@link #containsKey}, {@link #size}, {@link #isEmpty}, {@link
 * #asMap}, and {@link #toString}.
 *
 * <p>Instances of this class may be used by multiple threads concurrently. All operations are
 * atomic unless otherwise noted.
 *
 * <p>Instances of this class are serializable if the keys are serializable.

import java.io.Serializable;
import java.util.List;

import org.codelibs.fess.util.ComponentUtil;

/**
 * A pager class for managing pagination of failure URL records.
 * This class provides functionality to handle pagination of failed crawler URLs
 * with search filters and navigation capabilities.
 */
public class FailureUrlPager implements Serializable {

    /** Serial version UID for serialization compatibility. */