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;
            }