final SearchResponse searchResponse = client.prepareSearch(indexName)
                .setQuery(QueryBuilders.termQuery("hostname", hostname))
                .setSize(searchSize)
                .addSort("timestamp", SortOrder.ASC)
                .execute()
                .actionGet(fessConfig.getIndexSearchTimeout());

        final SearchHit[] hits = searchResponse.getHits().getHits();
        if (hits.length == 0) {

        // set query.
        final QueryBuilder q = buildQuery(query, fields);

        // set function score
        final QueryBuilder functionScoreQuery = buildFunctionScoreQuery(query, q);
        builder.addSort("_score", SortOrder.DESC);

        // set filter query.
        final List<QueryBuilder> filterList = new ArrayList<>(10);
        if (!tags.isEmpty()) {

         */
        protected void buildSort(final QueryContext queryContext, final QueryFieldConfig queryFieldConfig, final FessConfig fessConfig) {
            queryContext.sortBuilders().forEach(sortBuilder -> searchRequestBuilder.addSort(sortBuilder));
        }

        /**
         * Builds the rescorer configuration.
         *
         * @param queryHelper the query helper