import org.lastaflute.web.api.ApiFailureHook;
import org.lastaflute.web.api.ApiFailureResource;
import org.lastaflute.web.login.exception.LoginUnauthorizedException;
import org.lastaflute.web.response.ApiResponse;
import org.lastaflute.web.response.JsonResponse;

/**
 * The hook for API failure.
 *
 * @author jflute
 */
public class FessApiFailureHook implements ApiFailureHook { // #change_it for handling API failure

Pobres banners de cookies con todo su esfuerzo para obtener tu consentimiento para que la <abbr title="Esta es otra broma. No me prestes atención. Toma un café para tu cookie. ☕">API lo rechace</abbr>. 🍪

     * If an error occurs during execution, it will be cached and re-thrown for subsequent identical requests.
     *
     * @param <REQ> The request type
     * @param <REP> The response type
     * @param req The request object used as the cache key
     * @param supplier The function to execute and cache the result
     * @return The result from the supplier (either fresh or cached)

# Module okhttp-logging-interceptor

import jcifs.smb1.Config;

interface SmbConstants {

    /** Default SMB port number */
    int DEFAULT_PORT = 445;

    /** Default maximum multiplex count */
    int DEFAULT_MAX_MPX_COUNT = 10;
    /** Default response timeout in milliseconds */
    int DEFAULT_RESPONSE_TIMEOUT = 30000;
    /** Default socket timeout in milliseconds */
    int DEFAULT_SO_TIMEOUT = 35000;
    /** Default receive buffer size in bytes */

Cuando necesitas enviar datos desde un cliente (digamos, un navegador) a tu API, los envías como un **request body**.

Un **request** body es un dato enviado por el cliente a tu API. Un **response** body es el dato que tu API envía al cliente.

Tu API casi siempre tiene que enviar un **response** body. Pero los clientes no necesariamente necesitan enviar **request bodies** todo el tiempo, a veces solo solicitan un path, quizás con algunos parámetros de query, pero no envían un body.

            final CommonServerMessageBlock response) {
        if (log.isTraceEnabled()) {
            log.trace("Signing with seq " + this.signSequence);
        }

        ((ServerMessageBlock) request).setSignSeq(this.signSequence);
        if (response != null) {
            ((ServerMessageBlock) response).setSignSeq(this.signSequence + 1);
        }

        try {

    private static final int SMB2_HEADER_LENGTH = 64;

    /**
     * Build a minimal SMB2 header for a response.
     */
    private static byte[] buildSmb2Header() {
        byte[] header = Arrays.copyOf(SMBUtil.SMB2_HEADER, SMBUtil.SMB2_HEADER.length);
        // Mark as server->client response for realism
        SMBUtil.writeInt4(0x00000001, header, 16); // Flags
        // Command SMB2_CREATE (0x0005)

    }

    /**
     * Helper method to mock the response of an HttpURLConnection.
     */
    private void mockResponse(int code, String message, Map<String, List<String>> headers, InputStream errorStream) throws IOException {
        mockResponse(this.mockConnection, code, message, headers, errorStream);
    }

    /**
     * Helper method to mock the response of a specific HttpURLConnection instance.
     */

In this case, you could want to document how that external API *should* look like. What *path operation* it should have, what body it should expect, what response it should return, etc.

## An app with callbacks { #an-app-with-callbacks }

Let's see all this with an example.

Imagine you develop an app that allows creating invoices.