server/src/main/java/org/apache/druid/segment/realtime/plumber/FlushingPlumberSchool.java

/*
 * 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.druid.segment.realtime.plumber;

import com.fasterxml.jackson.annotation.JacksonInject;
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.google.common.base.Preconditions;
import org.apache.druid.client.cache.Cache;
import org.apache.druid.client.cache.CacheConfig;
import org.apache.druid.client.cache.CachePopulatorStats;
import org.apache.druid.java.util.emitter.service.ServiceEmitter;
import org.apache.druid.query.QueryProcessingPool;
import org.apache.druid.query.QueryRunnerFactoryConglomerate;
import org.apache.druid.segment.IndexIO;
import org.apache.druid.segment.IndexMergerV9;
import org.apache.druid.segment.indexing.DataSchema;
import org.apache.druid.segment.indexing.RealtimeTuningConfig;
import org.apache.druid.segment.join.JoinableFactory;
import org.apache.druid.segment.realtime.FireDepartmentMetrics;
import org.apache.druid.server.coordination.DataSegmentAnnouncer;
import org.joda.time.Duration;

/**
 * This plumber just drops segments at the end of a flush duration instead of handing them off. It is only useful if you want to run
 * a real time node without the rest of the Druid cluster.
 */
public class FlushingPlumberSchool extends RealtimePlumberSchool
{
  private static final Duration DEFAULT_FLUSH_DURATION = new Duration("PT1H");

  private final Duration flushDuration;

  private final ServiceEmitter emitter;
  private final QueryRunnerFactoryConglomerate conglomerate;
  private final DataSegmentAnnouncer segmentAnnouncer;
  private final QueryProcessingPool queryProcessingPool;
  private final JoinableFactory joinableFactory;
  private final IndexMergerV9 indexMergerV9;
  private final IndexIO indexIO;
  private final Cache cache;
  private final CacheConfig cacheConfig;
  private final CachePopulatorStats cachePopulatorStats;
  private final ObjectMapper objectMapper;

  @JsonCreator
  public FlushingPlumberSchool(
      @JsonProperty("flushDuration") Duration flushDuration,
      @JacksonInject ServiceEmitter emitter,
      @JacksonInject QueryRunnerFactoryConglomerate conglomerate,
      @JacksonInject DataSegmentAnnouncer segmentAnnouncer,
      @JacksonInject QueryProcessingPool queryProcessingPool,
      @JacksonInject JoinableFactory joinableFactory,
      @JacksonInject IndexMergerV9 indexMergerV9,
      @JacksonInject IndexIO indexIO,
      @JacksonInject Cache cache,
      @JacksonInject CacheConfig cacheConfig,
      @JacksonInject CachePopulatorStats cachePopulatorStats,
      @JacksonInject ObjectMapper objectMapper
  )
  {
    super(
        emitter,
        conglomerate,
        null,
        segmentAnnouncer,
        null,
        null,
        queryProcessingPool,
        joinableFactory,
        indexMergerV9,
        indexIO,
        cache,
        cacheConfig,
        cachePopulatorStats,
        objectMapper
    );

    this.flushDuration = flushDuration == null ? DEFAULT_FLUSH_DURATION : flushDuration;
    this.emitter = emitter;
    this.conglomerate = conglomerate;
    this.segmentAnnouncer = segmentAnnouncer;
    this.queryProcessingPool = queryProcessingPool;
    this.joinableFactory = joinableFactory;
    this.indexMergerV9 = Preconditions.checkNotNull(indexMergerV9, "Null IndexMergerV9");
    this.indexIO = Preconditions.checkNotNull(indexIO, "Null IndexIO");
    this.cache = cache;
    this.cacheConfig = cacheConfig;
    this.cachePopulatorStats = cachePopulatorStats;
    this.objectMapper = objectMapper;
  }

  @Override
  public Plumber findPlumber(
      final DataSchema schema,
      final RealtimeTuningConfig config,
      final FireDepartmentMetrics metrics
  )
  {
    verifyState();

    return new FlushingPlumber(
        flushDuration,
        schema,
        config,
        metrics,
        emitter,
        conglomerate,
        segmentAnnouncer,
        queryProcessingPool,
        joinableFactory,
        indexMergerV9,
        indexIO,
        cache,
        cacheConfig,
        cachePopulatorStats,
        objectMapper
    );
  }

  private void verifyState()
  {
    Preconditions.checkNotNull(conglomerate, "must specify a queryRunnerFactoryConglomerate to do this action.");
    Preconditions.checkNotNull(segmentAnnouncer, "must specify a segmentAnnouncer to do this action.");
    Preconditions.checkNotNull(emitter, "must specify a serviceEmitter to do this action.");
  }
}