code: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   *
   */
  
  package org.apache.skywalking.oap.server.storage.plugin.elasticsearch.query;
  
  import java.io.IOException;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Objects;
  import java.util.Set;
  import org.apache.skywalking.library.elasticsearch.requests.search.BoolQueryBuilder;
  import org.apache.skywalking.library.elasticsearch.requests.search.Query;
  import org.apache.skywalking.library.elasticsearch.requests.search.Search;
  import org.apache.skywalking.library.elasticsearch.requests.search.SearchBuilder;
  import org.apache.skywalking.library.elasticsearch.requests.search.aggregation.Aggregation;
  import org.apache.skywalking.library.elasticsearch.response.search.SearchHit;
  import org.apache.skywalking.library.elasticsearch.response.search.SearchResponse;
  import org.apache.skywalking.oap.server.core.analysis.manual.searchtag.TagAutocompleteData;
  import org.apache.skywalking.oap.server.core.analysis.manual.searchtag.TagType;
  import org.apache.skywalking.oap.server.core.query.input.Duration;
  import org.apache.skywalking.oap.server.core.storage.query.ITagAutoCompleteQueryDAO;
  import org.apache.skywalking.oap.server.library.client.elasticsearch.ElasticSearchClient;
  import org.apache.skywalking.oap.server.library.util.StringUtil;
  import org.apache.skywalking.oap.server.storage.plugin.elasticsearch.base.ElasticSearchConverter;
  import org.apache.skywalking.oap.server.storage.plugin.elasticsearch.base.EsDAO;
  import org.apache.skywalking.oap.server.storage.plugin.elasticsearch.base.IndexController;
  import org.apache.skywalking.oap.server.storage.plugin.elasticsearch.base.TimeRangeIndexNameGenerator;
  
  import static java.util.Objects.nonNull;
  
  public class TagAutoCompleteQueryDAO extends EsDAO implements ITagAutoCompleteQueryDAO {
      public TagAutoCompleteQueryDAO(ElasticSearchClient client) {
          super(client);
      }
  
      @Override
      public Set<String> queryTagAutocompleteKeys(final TagType tagType,
                                                  final int limit,
                                                  final Duration duration) throws IOException {
          // Tags combine records by day and es rolling index by day, need search the whole day
          // just use the time to locate the physical indexes and ignore time conditions.
          long startSecondTB = 0;
          long endSecondTB = 0;
          if (nonNull(duration)) {
              startSecondTB = duration.getStartTimeBucketInSec();
              endSecondTB = duration.getEndTimeBucketInSec();
          }
          BoolQueryBuilder query = Query.bool();
          query.must(Query.term(TagAutocompleteData.TAG_TYPE, tagType.name()));
          if (IndexController.LogicIndicesRegister.isMergedTable(TagAutocompleteData.INDEX_NAME)) {
              query.must(Query.term(IndexController.LogicIndicesRegister.METRIC_TABLE_NAME, TagAutocompleteData.INDEX_NAME));
          }
          final SearchBuilder search = Search.builder().query(query);
          search.aggregation(Aggregation.terms(TagAutocompleteData.TAG_KEY)
                                        .field(TagAutocompleteData.TAG_KEY)
                                        .size(limit));
  
          final SearchResponse response = getClient().search(
              new TimeRangeIndexNameGenerator(
                  IndexController.LogicIndicesRegister.getPhysicalTableName(TagAutocompleteData.INDEX_NAME),
                  startSecondTB, endSecondTB
              ),
              search.build()
          );
          Set<String> tagKeys = new HashSet<>();
          if (Objects.nonNull(response.getAggregations())) {
              Map<String, Object> terms =
                  (Map<String, Object>) response.getAggregations().get(TagAutocompleteData.TAG_KEY);
              List<Map<String, Object>> buckets = (List<Map<String, Object>>) terms.get("buckets");
  
              for (Map<String, Object> bucket : buckets) {
                  String tagKey = (String) bucket.get("key");
                  if (StringUtil.isEmpty(tagKey)) {
                      continue;
                  }
                  tagKeys.add(tagKey);
              }
          }
          return tagKeys;
      }
  
      @Override
      public Set<String> queryTagAutocompleteValues(final TagType tagType, final String tagKey,
                                                    final int limit,
                                                    final Duration duration) throws IOException {
          long startSecondTB = 0;
          long endSecondTB = 0;
          if (nonNull(duration)) {
              startSecondTB = duration.getStartTimeBucketInSec();
              endSecondTB = duration.getEndTimeBucketInSec();
          }
          BoolQueryBuilder query = Query.bool().must(Query.term(TagAutocompleteData.TAG_KEY, tagKey));
          query.must(Query.term(TagAutocompleteData.TAG_TYPE, tagType.name()));
          if (IndexController.LogicIndicesRegister.isMergedTable(TagAutocompleteData.INDEX_NAME)) {
              query.must(Query.term(IndexController.LogicIndicesRegister.METRIC_TABLE_NAME, TagAutocompleteData.INDEX_NAME));
          }
          final SearchBuilder search = Search.builder().query(query).size(limit);
  
          final SearchResponse response = getClient().search(
              new TimeRangeIndexNameGenerator(
                  IndexController.LogicIndicesRegister.getPhysicalTableName(TagAutocompleteData.INDEX_NAME),
                  startSecondTB, endSecondTB
              ),
              search.build()
          );
          Set<String> tagValues = new HashSet<>();
          for (SearchHit searchHit : response.getHits().getHits()) {
              TagAutocompleteData tag = new TagAutocompleteData.Builder().storage2Entity(
                  new ElasticSearchConverter.ToEntity(TagAutocompleteData.INDEX_NAME, searchHit.getSource()));
              tagValues.add(tag.getTagValue());
          }
          return tagValues;
      }
  }
  