{* ../../docs_src/openapi_callbacks/tutorial001_py310.py hl[1,23] *}

### Crea la *path operation* del callback { #create-the-callback-path-operation }

Para crear la *path operation* del callback usa el mismo `APIRouter` que creaste arriba.

Debería verse como una *path operation* normal de FastAPI:

* Probablemente debería tener una declaración del body que debería recibir, por ejemplo `body: InvoiceEvent`.

   * An object that holds the final result of an asynchronous {@link ClosingFuture} operation and
   * allows the user to close all the closeable objects that were captured during it for later
   * closing.
   *
   * <p>The asynchronous operation will have completed before this object is created.
   *
   * @param <V> the type of the value of a successful operation
   * @see ClosingFuture#finishToValueAndCloser(ValueAndCloserConsumer, Executor)

/**
 * Admin action for maintenance operations including reindexing, log management,
 * and system diagnostics.
 */
public class AdminMaintenanceAction extends FessAdminAction {

    /**
     * Default constructor for AdminMaintenanceAction.
     */
    public AdminMaintenanceAction() {
        super();
    }

    /**
     * Role identifier for admin maintenance operations.
     */

`BackgroundTasks` の使用は依存性注入システムでも機能し、様々な階層 (*path operations 関数*、依存性 (依存可能性)、サブ依存性など) で `BackgroundTasks` 型のパラメーターを宣言できます。

**FastAPI** は、それぞれの場合の処理​​方法と同じオブジェクトの再利用方法を知っているため、すべてのバックグラウンドタスクがマージされ、バックグラウンドで後で実行されます。

{* ../../docs_src/background_tasks/tutorial002.py hl[13,15,22,25] *}

この例では、レスポンスが送信された *後* にメッセージが `log.txt` ファイルに書き込まれます。

リクエストにクエリがあった場合、バックグラウンドタスクでログに書き込まれます。

        }
    }

    /**
     * Validates integer for safe arithmetic operations
     *
     * @param a first operand
     * @param b second operand
     * @param operation the operation name
     * @throws ArithmeticException if operation would overflow
     */
    public static void validateIntegerAddition(int a, int b, String operation) {
        long result = (long) a + (long) b;

    // Attribute
    // =========
    /** Search engine client for document operations */
    @Resource
    protected SearchEngineClient searchEngineClient;

    // ===================================================================================
    // Search Execute
    //

    /**
     * Performs bulk document operations (index multiple documents).
     * Validates document fields and adds default values where necessary.

/**
 * Helper class for indexing operations in the Fess search engine.
 * This class provides functionality for sending documents to the search engine,
 * managing document lifecycle operations (create, update, delete), and handling
 * thumbnail processing during indexing.
 *
 * <p>The IndexingHelper manages bulk operations, handles retries on failures,
 * and provides various query-based operations for document management.

import jcifs.internal.smb2.ServerMessageBlock2Request;
import jcifs.internal.smb2.Smb2Constants;
import jcifs.internal.util.SMBUtil;

/**
 * SMB2 IOCTL request message. This command is used to perform device control operations
 * on files, pipes, or the server itself.
 *
 * @author mbechler
 *
 */
public class Smb2IoctlRequest extends ServerMessageBlock2Request<Smb2IoctlResponse> implements RequestWithFileId {

    /**

import org.apache.maven.api.services.Result;

/**
 * A record representing the result of a single request operation, containing the original request,
 * the result (if successful), and any error that occurred during processing.
 * <p>
 * This class is immutable and thread-safe, suitable for use in concurrent operations.
 *
 * @param <REQ> The type of the request
 * @param <REP> The type of the response, which must extend {@code Result<REQ>}

 *
 * <ul>
 *   <li><b>Finite:</b> Many operations, such as {@link #length()} and {@link #read()}, will either
 *       block indefinitely or fail if the source creates an infinite reader.
 *   <li><b>Non-destructive:</b> A <i>destructive</i> reader will consume or otherwise alter the
 *       source as they are read from it. A source that provides such readers will not be reusable,