final String authorities = fessConfig.getFesenHttpSslCertificateAuthorities();
        if (StringUtil.isNotBlank(authorities)) {
            if (logger.isDebugEnabled()) {
                logger.debug("Loading certificate_authorities: path={}", authorities);
            }
            try (final InputStream in = new FileInputStream(authorities)) {

        }
        final String authorities = fessConfig.getFesenHttpSslCertificateAuthorities();
        if (StringUtil.isNotBlank(authorities)) {
            builder.put("http.ssl.certificate_authorities", authorities);
        }
        return new HttpClient(builder.build(), null);
    }