.prepareGetAliases(getUpdateAlias(index))
                        .execute()
                        .actionGet(suggestSettings.getIndicesTimeout());
                getAliasesResponse.getAliases().keySet().forEach(prevIndices::add);
            }

            final String mappingSource = getDefaultMappings();
            final String settingsSource = getDefaultIndexSettings();

        final Settings settings = response.getIndexToSettings().get(analyzerSettingsIndexName);
        final Settings analyzerSettings = settings.getAsSettings("index.analysis.analyzer");
        return analyzerSettings.getAsGroups().keySet();
    }

    /**
     * Get field analyzer mapping.
     * @return Field analyzer mapping
     */
    protected Map<String, FieldAnalyzerMapping> getFieldAnalyzerMapping() {