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);
                }
            });
        }

            logger.debug("Backup download requested: id={}", 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()) {

     */
    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.");
        }

            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));

        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<>();

        if (StringUtil.isEmpty(pi.getName())) {
            throwValidationErrorApi(messages -> messages.addErrorsStorageFileNotFound(GLOBAL));
        }
        return asStream(pi.getName()).contentTypeOctetStream().stream(out -> {
            try {
                downloadObject(getObjectName(pi.getPath(), pi.getName()), out);
            } catch (final StorageException e) {

        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));

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

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

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