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)) {

signs the other party's chain.

Well-Known Certificate Authorities
----------------------------------

In these examples we've prearranged which root certificates to trust. But for regular HTTPS on the
Internet this set of trusted root certificates is usually provided by default by the host platform.
Such a set typically includes many root certificates from well-known certificate authorities like
Entrust and Verisign.

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

    /**

     * connections rely on only the [SSL socket factory][sslSocketFactory] to establish trust.
     * Pinning certificates avoids the need to trust certificate authorities.
     */
    fun certificatePinner(certificatePinner: CertificatePinner) =
      apply {
        if (certificatePinner != this.certificatePinner) {
          this.routeDatabase = null
        }

search_engine.type=default
# The URL of the search engine HTTP endpoint.
# For IPv6 environments, use brackets around the IPv6 address (e.g., http://[::1]:9201)
search_engine.http.url=http://localhost:9201
# Path to SSL certificate authorities for secure HTTP connections.
search_engine.http.ssl.certificate_authorities=
# Username for authenticating to the search engine.
search_engine.username=
# Password for authenticating to the search engine.

    String getSearchEngineHttpUrl();

    /**
     * Get the value for the key 'search_engine.http.ssl.certificate_authorities'. <br>
     * The value is, e.g.  <br>
     * comment: Path to SSL certificate authorities for secure HTTP connections.
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getSearchEngineHttpSslCertificateAuthorities();

    /**