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.List;
  import java.util.concurrent.CompletableFuture;
  import lombok.extern.slf4j.Slf4j;
  import org.apache.skywalking.library.elasticsearch.bulk.BulkProcessor;
  import org.apache.skywalking.oap.server.core.storage.IBatchDAO;
  import org.apache.skywalking.oap.server.library.client.elasticsearch.ElasticSearchClient;
  import org.apache.skywalking.oap.server.library.client.elasticsearch.IndexRequestWrapper;
  import org.apache.skywalking.oap.server.library.client.elasticsearch.UpdateRequestWrapper;
  import org.apache.skywalking.oap.server.library.client.request.InsertRequest;
  import org.apache.skywalking.oap.server.library.client.request.PrepareRequest;
  import org.apache.skywalking.oap.server.library.util.CollectionUtils;
  
  @Slf4j
  public class BatchProcessEsDAO extends EsDAO implements IBatchDAO {
      private volatile BulkProcessor bulkProcessor;
      private final int bulkActions;
      private final int flushInterval;
      private final int concurrentRequests;
      private final int batchOfBytes;
  
      public BatchProcessEsDAO(ElasticSearchClient client,
                               int bulkActions,
                               int flushInterval,
                               int concurrentRequests,
                               int batchOfBytes) {
          super(client);
          this.bulkActions = bulkActions;
          this.flushInterval = flushInterval;
          this.concurrentRequests = concurrentRequests;
          this.batchOfBytes = batchOfBytes;
      }
  
      @Override
      public void insert(InsertRequest insertRequest) {
          if (bulkProcessor == null) {
              synchronized (this) {
                  if (bulkProcessor == null) {
                      this.bulkProcessor = getClient().createBulkProcessor(
                          bulkActions, flushInterval, concurrentRequests, batchOfBytes);
                  }
              }
          }
  
          this.bulkProcessor.add(((IndexRequestWrapper) insertRequest).getRequest());
      }
  
      @Override
      public CompletableFuture<Void> flush(List<PrepareRequest> prepareRequests) {
          if (bulkProcessor == null) {
              synchronized (this) {
                  if (bulkProcessor == null) {
                      this.bulkProcessor = getClient().createBulkProcessor(
                          bulkActions, flushInterval, concurrentRequests, batchOfBytes);
                  }
              }
          }
  
          if (CollectionUtils.isNotEmpty(prepareRequests)) {
              return CompletableFuture.allOf(prepareRequests.stream().map(prepareRequest -> {
                  if (prepareRequest instanceof InsertRequest) {
                      return bulkProcessor.add(((IndexRequestWrapper) prepareRequest).getRequest())
                          .whenComplete((v, throwable) -> {
                              if (throwable == null) {
                                  // Insert completed
                                  ((IndexRequestWrapper) prepareRequest).onInsertCompleted();
                              }
                          });
                  } else {
                      return bulkProcessor.add(((UpdateRequestWrapper) prepareRequest).getRequest())
                          .whenComplete((v, throwable) -> {
                              if (throwable != null) {
                                  // Update failure
                                  ((UpdateRequestWrapper) prepareRequest).onUpdateFailure();
                              }
                          });
                  }
              }).toArray(CompletableFuture[]::new));
          }
          return CompletableFuture.completedFuture(null);
      }
  
      @Override
      public void endOfFlush() {
          // Flush forcibly due to this kind of metrics has been pushed into the bulk processor.
          if (bulkProcessor != null) {
              bulkProcessor.flush();
          }
      }
  }
  