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.zipkin;
  
  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.SearchParams;
  import org.apache.skywalking.library.elasticsearch.requests.search.Sort;
  import org.apache.skywalking.library.elasticsearch.requests.search.aggregation.Aggregation;
  import org.apache.skywalking.library.elasticsearch.requests.search.aggregation.BucketOrder;
  import org.apache.skywalking.library.elasticsearch.requests.search.aggregation.TermsAggregationBuilder;
  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.TimeBucket;
  import org.apache.skywalking.oap.server.core.query.input.Duration;
  import org.apache.skywalking.oap.server.core.storage.query.IZipkinQueryDAO;
  import org.apache.skywalking.oap.server.core.zipkin.ZipkinServiceRelationTraffic;
  import org.apache.skywalking.oap.server.core.zipkin.ZipkinServiceSpanTraffic;
  import org.apache.skywalking.oap.server.core.zipkin.ZipkinServiceTraffic;
  import org.apache.skywalking.oap.server.core.zipkin.ZipkinSpanRecord;
  import org.apache.skywalking.oap.server.library.client.elasticsearch.ElasticSearchClient;
  import org.apache.skywalking.oap.server.library.client.elasticsearch.ElasticSearchScroller;
  import org.apache.skywalking.oap.server.library.util.CollectionUtils;
  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.RoutingUtils;
  import org.apache.skywalking.oap.server.storage.plugin.elasticsearch.base.TimeRangeIndexNameGenerator;
  import zipkin2.Span;
  import zipkin2.storage.QueryRequest;
  
  import java.util.ArrayList;
  import java.util.HashSet;
  import java.util.LinkedHashMap;
  import java.util.List;
  import java.util.Map;
  import java.util.Objects;
  import java.util.Set;
  
  public class ZipkinQueryEsDAO extends EsDAO implements IZipkinQueryDAO {
      private final static int NAME_QUERY_MAX_SIZE = 10000;
      private final static int SCROLLING_BATCH_SIZE = 5000;
  
      public ZipkinQueryEsDAO(ElasticSearchClient client) {
          super(client);
      }
  
      @Override
      public List<String> getServiceNames() {
          final String index =
              IndexController.LogicIndicesRegister.getPhysicalTableName(ZipkinServiceTraffic.INDEX_NAME);
          final BoolQueryBuilder query = Query.bool();
          if (IndexController.LogicIndicesRegister.isMergedTable(ZipkinServiceTraffic.INDEX_NAME)) {
              query.must(Query.term(IndexController.LogicIndicesRegister.METRIC_TABLE_NAME, ZipkinServiceTraffic.INDEX_NAME));
          }
          final SearchBuilder search = Search.builder().query(query).size(SCROLLING_BATCH_SIZE);
  
          final var scroller = ElasticSearchScroller
              .<String>builder()
              .client(getClient())
              .search(search.build())
              .index(index)
              .resultConverter(hit -> {
                  final var sourceAsMap = hit.getSource();
                  final var record = new ZipkinServiceTraffic.Builder().storage2Entity(
                      new ElasticSearchConverter.ToEntity(ZipkinServiceTraffic.INDEX_NAME, sourceAsMap));
                  return record.getServiceName();
              })
              .build();
          return scroller.scroll();
      }
  
      @Override
      public List<String> getRemoteServiceNames(final String serviceName) {
          String index = IndexController.LogicIndicesRegister.getPhysicalTableName(
              ZipkinServiceRelationTraffic.INDEX_NAME);
          BoolQueryBuilder query = Query.bool().must(Query.term(ZipkinServiceRelationTraffic.SERVICE_NAME, serviceName));
          if (IndexController.LogicIndicesRegister.isMergedTable(ZipkinServiceRelationTraffic.INDEX_NAME)) {
              query.must(Query.term(IndexController.LogicIndicesRegister.METRIC_TABLE_NAME, ZipkinServiceRelationTraffic.INDEX_NAME));
          }
          SearchBuilder search = Search.builder().query(query).size(NAME_QUERY_MAX_SIZE);
          SearchResponse response = getClient().search(index, search.build());
          List<String> remoteServices = new ArrayList<>();
          for (SearchHit searchHit : response.getHits()) {
              Map<String, Object> sourceAsMap = searchHit.getSource();
              ZipkinServiceRelationTraffic record = new ZipkinServiceRelationTraffic.Builder().storage2Entity(
                  new ElasticSearchConverter.ToEntity(ZipkinServiceRelationTraffic.INDEX_NAME, sourceAsMap));
              remoteServices.add(record.getRemoteServiceName());
          }
          return remoteServices;
      }
  
      @Override
      public List<String> getSpanNames(final String serviceName) {
          String index = IndexController.LogicIndicesRegister.getPhysicalTableName(ZipkinServiceSpanTraffic.INDEX_NAME);
          BoolQueryBuilder query = Query.bool().must(Query.term(ZipkinServiceSpanTraffic.SERVICE_NAME, serviceName));
          if (IndexController.LogicIndicesRegister.isMergedTable(ZipkinServiceSpanTraffic.INDEX_NAME)) {
              query.must(Query.term(IndexController.LogicIndicesRegister.METRIC_TABLE_NAME, ZipkinServiceSpanTraffic.INDEX_NAME));
          }
          SearchBuilder search = Search.builder().query(query).size(NAME_QUERY_MAX_SIZE);
          SearchResponse response = getClient().search(index, search.build());
          List<String> spanNames = new ArrayList<>();
          for (SearchHit searchHit : response.getHits()) {
              Map<String, Object> sourceAsMap = searchHit.getSource();
              ZipkinServiceSpanTraffic record = new ZipkinServiceSpanTraffic.Builder().storage2Entity(
                  new ElasticSearchConverter.ToEntity(ZipkinServiceSpanTraffic.INDEX_NAME, sourceAsMap));
              spanNames.add(record.getSpanName());
          }
          return spanNames;
      }
  
      @Override
      public List<Span> getTrace(final String traceId) {
          String index = IndexController.LogicIndicesRegister.getPhysicalTableName(ZipkinSpanRecord.INDEX_NAME);
          BoolQueryBuilder query = Query.bool().must(Query.term(ZipkinSpanRecord.TRACE_ID, traceId));
          SearchBuilder search = Search.builder().query(query).size(SCROLLING_BATCH_SIZE);
          final var params = new SearchParams();
          RoutingUtils.addRoutingValueToSearchParam(params, traceId);
  
          final var scroller = ElasticSearchScroller
              .<Span>builder()
              .client(getClient())
              .search(search.build())
              .index(index)
              .params(params)
              .resultConverter(searchHit -> {
                  final var sourceAsMap = searchHit.getSource();
                  final var record = new ZipkinSpanRecord.Builder().storage2Entity(
                      new ElasticSearchConverter.ToEntity(ZipkinSpanRecord.INDEX_NAME, sourceAsMap));
                  return ZipkinSpanRecord.buildSpanFromRecord(record);
              })
              .build();
          return scroller.scroll();
      }
  
      @Override
      public List<List<Span>> getTraces(final QueryRequest request, Duration duration) {
          final long startTimeMillis = duration.getStartTimestamp();
          final long endTimeMillis = duration.getEndTimestamp();
          BoolQueryBuilder query = Query.bool();
          if (startTimeMillis > 0 && endTimeMillis > 0) {
              query.must(Query.range(ZipkinSpanRecord.TIMESTAMP_MILLIS)
                              .gte(startTimeMillis)
                              .lte(endTimeMillis));
          }
          if (!StringUtil.isEmpty(request.serviceName())) {
              query.must(Query.term(ZipkinSpanRecord.LOCAL_ENDPOINT_SERVICE_NAME, request.serviceName()));
          }
  
          if (!StringUtil.isEmpty(request.remoteServiceName())) {
              query.must(Query.term(ZipkinSpanRecord.REMOTE_ENDPOINT_SERVICE_NAME, request.remoteServiceName()));
          }
  
          if (!StringUtil.isEmpty(request.spanName())) {
              query.must(Query.term(ZipkinSpanRecord.NAME, request.spanName()));
          }
  
          if (!CollectionUtils.isEmpty(request.annotationQuery())) {
              for (Map.Entry<String, String> annotation : request.annotationQuery().entrySet()) {
                  if (annotation.getValue().isEmpty()) {
                      query.must(Query.term(ZipkinSpanRecord.QUERY, annotation.getKey()));
                  } else {
                      query.must(Query.term(ZipkinSpanRecord.QUERY, annotation.getKey() + "=" + annotation.getValue()));
                  }
              }
          }
  
          if (request.minDuration() != null) {
              query.must(Query.range(ZipkinSpanRecord.DURATION).gte(request.minDuration()));
          }
          if (request.maxDuration() != null) {
              query.must(Query.range(ZipkinSpanRecord.DURATION).lte(request.maxDuration()));
          }
          final TermsAggregationBuilder traceIdAggregation =
              Aggregation.terms(ZipkinSpanRecord.TRACE_ID)
                         .field(ZipkinSpanRecord.TRACE_ID)
                         .executionHint(TermsAggregationBuilder.ExecutionHint.MAP)
                         .collectMode(TermsAggregationBuilder.CollectMode.BREADTH_FIRST)
                         .size(request.limit()).subAggregation(Aggregation.min(ZipkinSpanRecord.TIMESTAMP_MILLIS)
                                                                          .field(ZipkinSpanRecord.TIMESTAMP_MILLIS))
                         .order(BucketOrder.aggregation(ZipkinSpanRecord.TIMESTAMP_MILLIS, false));
  
          SearchBuilder search = Search.builder().query(query).aggregation(traceIdAggregation);
          SearchResponse traceIdResponse = getClient().search(new TimeRangeIndexNameGenerator(
              IndexController.LogicIndicesRegister.getPhysicalTableName(ZipkinSpanRecord.INDEX_NAME),
              TimeBucket.getRecordTimeBucket(startTimeMillis),
              TimeBucket.getRecordTimeBucket(endTimeMillis)
          ), search.build());
          Set<String> traceIds = new HashSet<>();
          if (Objects.nonNull(traceIdResponse.getAggregations())) {
              final Map<String, Object> idTerms =
                  (Map<String, Object>) traceIdResponse.getAggregations().get(ZipkinSpanRecord.TRACE_ID);
              final List<Map<String, Object>> buckets =
                  (List<Map<String, Object>>) idTerms.get("buckets");
  
              for (Map<String, Object> idBucket : buckets) {
                  traceIds.add((String) idBucket.get("key"));
              }
          }
          return getTraces(traceIds);
      }
  
      @Override
      public List<List<Span>> getTraces(final Set<String> traceIds) {
          String index = IndexController.LogicIndicesRegister.getPhysicalTableName(ZipkinSpanRecord.INDEX_NAME);
          BoolQueryBuilder query = Query.bool().must(Query.terms(ZipkinSpanRecord.TRACE_ID, new ArrayList<>(traceIds)));
          SearchBuilder search = Search.builder().query(query).sort(ZipkinSpanRecord.TIMESTAMP_MILLIS, Sort.Order.DESC)
                                       .size(SCROLLING_BATCH_SIZE); //max span size for 1 scroll
          final SearchParams params = new SearchParams().scroll(SCROLL_CONTEXT_RETENTION);
          RoutingUtils.addRoutingValuesToSearchParam(params, traceIds);
  
          SearchResponse response = getClient().search(index, search.build(), params);
          final Set<String> scrollIds = new HashSet<>();
          Map<String, List<Span>> groupedByTraceId = new LinkedHashMap<String, List<Span>>();
          try {
              while (response.getHits().getHits().size() != 0) {
                  String scrollId = response.getScrollId();
                  scrollIds.add(scrollId);
                  buildTraces(response, groupedByTraceId);
                  if (response.getHits().getHits().size() < SCROLLING_BATCH_SIZE) {
                      break;
                  }
                  response = getClient().scroll(SCROLL_CONTEXT_RETENTION, scrollId);
              }
          } finally {
              scrollIds.forEach(getClient()::deleteScrollContextQuietly);
          }
          return new ArrayList<>(groupedByTraceId.values());
      }
  
      private void buildTraces(SearchResponse response, Map<String, List<Span>> groupedByTraceId) {
          for (SearchHit searchHit : response.getHits()) {
              Map<String, Object> sourceAsMap = searchHit.getSource();
              ZipkinSpanRecord record = new ZipkinSpanRecord.Builder().storage2Entity(
                  new ElasticSearchConverter.ToEntity(ZipkinSpanRecord.INDEX_NAME, sourceAsMap));
              Span span = ZipkinSpanRecord.buildSpanFromRecord(record);
              String traceId = span.traceId();
              groupedByTraceId.putIfAbsent(traceId, new ArrayList<>());
              groupedByTraceId.get(traceId).add(span);
          }
      }
  }
  