return System.getenv();
    }

    /**
     * Gets the version of the Fess application.
     *
     * @return The version string.
     */
    public String getVersion() {
        return version;
    }

    /**
     * Gets the major version number.
     *
     * @return The major version number.
     */
    public int getMajorVersion() {

                final Map<String, Object> docMap = new HashMap<>(source);
                docMap.put(fessConfig.getIndexFieldId(), hit.getId());
                docMap.put(fessConfig.getIndexFieldVersion(), hit.getVersion());
                docMap.put(fessConfig.getIndexFieldSeqNo(), hit.getSeqNo());
                docMap.put(fessConfig.getIndexFieldPrimaryTerm(), hit.getPrimaryTerm());
                return docMap;
            }