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.base;
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import lombok.extern.slf4j.Slf4j;
  import org.apache.skywalking.library.elasticsearch.exception.ResponseException;
  import org.apache.skywalking.oap.server.core.analysis.DownSampling;
  import org.apache.skywalking.oap.server.core.storage.IHistoryDeleteDAO;
  import org.apache.skywalking.oap.server.core.storage.model.Model;
  import org.apache.skywalking.oap.server.library.client.elasticsearch.ElasticSearchClient;
  import org.joda.time.DateTime;
  
  @Slf4j
  public class HistoryDeleteEsDAO extends EsDAO implements IHistoryDeleteDAO {
      private final Map<String, Long> indexLatestSuccess;
  
      public HistoryDeleteEsDAO(ElasticSearchClient client) {
          super(client);
          this.indexLatestSuccess = new HashMap<>();
      }
  
      @Override
      public void deleteHistory(Model model, String timeBucketColumnName, int ttl) {
          ElasticSearchClient client = getClient();
  
          if (!model.isRecord()) {
              if (!DownSampling.Minute.equals(model.getDownsampling())) {
                  /*
                   * In ElasticSearch storage, the TTL triggers the index deletion directly.
                   * As all metrics data in different down sampling rule of one day are in the same index, the deletion operation
                   * is only required to run once.
                   */
                  return;
              }
          }
          long deadline = Long.parseLong(new DateTime().plusDays(-ttl).toString("yyyyMMdd"));
          String tableName = IndexController.INSTANCE.getTableName(model);
          Long latestSuccessDeadline = this.indexLatestSuccess.get(model.getName());
          if (latestSuccessDeadline != null && deadline <= latestSuccessDeadline) {
              if (log.isDebugEnabled()) {
                  log.debug("Index = {} already deleted, skip, deadline = {}, ttl = {}", tableName, deadline, ttl);
              }
              return;
          }
          Collection<String> indices = client.retrievalIndexByAliases(tableName);
  
          if (log.isDebugEnabled()) {
              log.debug("Deadline = {}, indices = {}, ttl = {}", deadline, indices, ttl);
          }
  
          List<String> prepareDeleteIndexes = new ArrayList<>();
          List<String> leftIndices = new ArrayList<>();
          for (String index : indices) {
              long timeSeries = TimeSeriesUtils.isolateTimeFromIndexName(index);
              if (deadline >= timeSeries) {
                  prepareDeleteIndexes.add(index);
              } else {
                  leftIndices.add(index);
              }
          }
          if (log.isDebugEnabled()) {
              log.debug("Indices to be deleted: {}", prepareDeleteIndexes);
          }
          for (String prepareDeleteIndex : prepareDeleteIndexes) {
              client.deleteByIndexName(prepareDeleteIndex);
          }
          String latestIndex = TimeSeriesUtils.latestWriteIndexName(model);
          String formattedLatestIndex = client.formatIndexName(latestIndex);
          if (!leftIndices.contains(formattedLatestIndex)) {
              try {
                  client.createIndex(latestIndex);
              } catch (ResponseException e) {
                  if (e.getStatusCode() == 400 && client.isExistsIndex(latestIndex)) {
                      if (log.isDebugEnabled()) {
                          log.debug(
                              "Failed to create index {}, index is already created.", latestIndex);
                      }
                  } else {
                      throw e;
                  }
              }
          }
          this.indexLatestSuccess.put(tableName, deadline);
      }
  }
  