final Map<String, Object> newDoc = fessConfig.convertToStorableDoc(doc);
            newDoc.put(indexFieldId, crawlingInfoHelper.generateId(newDoc));
            newDoc.put(indexFieldDocId, systemHelper.generateDocId(newDoc));
            if (newDoc.get(indexFieldLang) instanceof final List<?> langList) {
                if (langList.contains("auto")) {
                    newDoc.remove(indexFieldLang);
                }