osddHelper.setContentType("application/opensearchdescription+xml");
        osddHelper.init();
        assertFalse(osddHelper.hasOpenSearchFile());

        try {
            osddHelper.asStream();
            fail();
        } catch (final Exception e) {
            assertEquals("Unsupported Open Search Description Document response.", e.getMessage());
        }
    }

     *
     * @param id the backup file ID to download
     * @return stream response containing the backup file data
     */
    // GET /api/admin/backup/file/{id}
    @Execute
    public StreamResponse get$file(final String id) {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        if (stream(fessConfig.getIndexBackupAllTargets()).get(stream -> stream.anyMatch(s -> s.equals(id)))) {

    @Execute
    @Secured({ ROLE, ROLE + VIEW })
    public ActionResponse download(final String id) {
        if (stream(fessConfig.getIndexBackupAllTargets()).get(stream -> stream.anyMatch(s -> s.equals(id)))) {
            if ("system.properties".equals(id)) {
                return asStream(id).contentTypeOctetStream().stream(out -> {
                    try (final ByteArrayOutputStream baos = new ByteArrayOutputStream()) {

    /**
     * Returns the OSDD document.
     *
     * @return the OSDD document as a stream response
     */
    @Execute
    public ActionResponse index() {
        if (isLoginRequired()) {
            return redirectToLogin();
        }
        return osddHelper.asStream();
    }

        if (StringUtil.isNotBlank(logFilePath) && isLogFilename(filename)) {
            final Path path = Paths.get(logFilePath, filename);
            return asStream(filename).contentTypeOctetStream().stream(out -> {
                try (InputStream in = Files.newInputStream(path)) {
                    out.write(in);
                }
            });
        }

     */
    public boolean hasOpenSearchFile() {
        return osddFile != null;
    }

    /**
     * Returns the OSDD as a stream response.
     *
     * @return the stream response
     */
    public StreamResponse asStream() {
        if (osddFile == null) {
            throw ComponentUtil.getResponseManager().new404("Unsupported Open Search Description Document response.");
        }

        final String logFilePath = systemHelper.getLogFilePath();
        if (StringUtil.isNotBlank(logFilePath)) {
            final Path logDirPath = Paths.get(logFilePath);
            try (Stream<Path> stream = Files.list(logDirPath)) {
                stream.filter(entry -> isLogFilename(entry.getFileName().toString())).sorted().forEach(filePath -> {
                    final Map<String, Object> map = new HashMap<>();

            }
            // 404
            throw responseManager.new404("Thumbnail for " + form.docId + " is under generating.");
        }

        return asStream(form.docId).contentType(getImageMimeType(thumbnailFile)).stream(out -> {
            try (BufferedInputStream in = new BufferedInputStream(new FileInputStream(thumbnailFile))) {
                out.write(in);
            }
        });
    }

            saveError(messages -> messages.addErrorsDocidNotFound(GLOBAL, form.docId));
            return redirect(ErrorAction.class);
        }

        final StreamResponse response =
                asStream(DocumentUtil.getValue(doc, fessConfig.getIndexFieldDocId(), String.class)).contentType("text/html; charset=UTF-8")
                        .data(content.getBytes(Constants.CHARSET_UTF_8));

        validateApi(body, messages -> {});
        return kuromojiService.getKuromojiFile(body.dictId)
                .map(file -> asStream(new File(file.getPath()).getName()).contentTypeOctetStream().stream(out -> {
                    file.writeOut(out);
                }))
                .orElseGet(() -> {
                    throwValidationErrorApi(messages -> messages.addErrorsFailedToDownloadProtwordsFile(GLOBAL));