hudi-client/hudi-spark-client/src/main/java/org/apache/hudi/index/simple/SparkHoodieSimpleIndex.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.hudi.index.simple;

import org.apache.hudi.client.WriteStatus;
import org.apache.hudi.client.utils.SparkMemoryUtils;
import org.apache.hudi.client.common.HoodieEngineContext;
import org.apache.hudi.client.common.HoodieSparkEngineContext;
import org.apache.hudi.common.model.HoodieBaseFile;
import org.apache.hudi.common.model.HoodieKey;
import org.apache.hudi.common.model.HoodieRecord;
import org.apache.hudi.common.model.HoodieRecordLocation;
import org.apache.hudi.common.model.HoodieRecordPayload;
import org.apache.hudi.common.util.Option;
import org.apache.hudi.common.util.collection.Pair;
import org.apache.hudi.config.HoodieWriteConfig;
import org.apache.hudi.index.HoodieIndexUtils;
import org.apache.hudi.index.SparkHoodieIndex;
import org.apache.hudi.io.HoodieKeyLocationFetchHandle;
import org.apache.hudi.table.HoodieTable;

import org.apache.spark.api.java.JavaPairRDD;
import org.apache.spark.api.java.JavaRDD;
import org.apache.spark.api.java.JavaSparkContext;

import java.util.List;

import scala.Tuple2;

import static org.apache.hudi.index.HoodieIndexUtils.getLatestBaseFilesForAllPartitions;

/**
 * A simple index which reads interested fields(record key and partition path) from base files and
 * joins with incoming records to find the tagged location.
 *
 * @param <T>
 */
@SuppressWarnings("checkstyle:LineLength")
public class SparkHoodieSimpleIndex<T extends HoodieRecordPayload> extends SparkHoodieIndex<T> {

  public SparkHoodieSimpleIndex(HoodieWriteConfig config) {
    super(config);
  }

  @Override
  public JavaRDD<WriteStatus> updateLocation(JavaRDD<WriteStatus> writeStatusRDD, HoodieEngineContext context,
                                             HoodieTable<T, JavaRDD<HoodieRecord<T>>, JavaRDD<HoodieKey>, JavaRDD<WriteStatus>> hoodieTable) {
    return writeStatusRDD;
  }

  @Override
  public boolean rollbackCommit(String commitTime) {
    return true;
  }

  @Override
  public boolean isGlobal() {
    return false;
  }

  @Override
  public boolean canIndexLogFiles() {
    return false;
  }

  @Override
  public boolean isImplicitWithStorage() {
    return true;
  }

  @Override
  public JavaRDD<HoodieRecord<T>> tagLocation(JavaRDD<HoodieRecord<T>> recordRDD,
                                              HoodieEngineContext context,
                                              HoodieTable<T, JavaRDD<HoodieRecord<T>>, JavaRDD<HoodieKey>, JavaRDD<WriteStatus>> hoodieTable) {
    return tagLocationInternal(recordRDD, context, hoodieTable);
  }

  /**
   * Tags records location for incoming records.
   *
   * @param inputRecordRDD {@link JavaRDD} of incoming records
   * @param context            instance of {@link HoodieEngineContext} to use
   * @param hoodieTable    instance of {@link HoodieTable} to use
   * @return {@link JavaRDD} of records with record locations set
   */
  protected JavaRDD<HoodieRecord<T>> tagLocationInternal(JavaRDD<HoodieRecord<T>> inputRecordRDD, HoodieEngineContext context,
                                                         HoodieTable<T, JavaRDD<HoodieRecord<T>>, JavaRDD<HoodieKey>, JavaRDD<WriteStatus>> hoodieTable) {
    if (config.getSimpleIndexUseCaching()) {
      inputRecordRDD.persist(SparkMemoryUtils.getSimpleIndexInputStorageLevel(config.getProps()));
    }

    JavaPairRDD<HoodieKey, HoodieRecord<T>> keyedInputRecordRDD = inputRecordRDD.mapToPair(record -> new Tuple2<>(record.getKey(), record));
    JavaPairRDD<HoodieKey, HoodieRecordLocation> existingLocationsOnTable = fetchRecordLocationsForAffectedPartitions(keyedInputRecordRDD.keys(), context, hoodieTable,
        config.getSimpleIndexParallelism());

    JavaRDD<HoodieRecord<T>> taggedRecordRDD = keyedInputRecordRDD.leftOuterJoin(existingLocationsOnTable)
        .map(entry -> {
          final HoodieRecord<T> untaggedRecord = entry._2._1;
          final Option<HoodieRecordLocation> location = Option.ofNullable(entry._2._2.orNull());
          return HoodieIndexUtils.getTaggedRecord(untaggedRecord, location);
        });

    if (config.getSimpleIndexUseCaching()) {
      inputRecordRDD.unpersist();
    }
    return taggedRecordRDD;
  }

  /**
   * Fetch record locations for passed in {@link HoodieKey}s.
   *
   * @param hoodieKeys  {@link JavaRDD} of {@link HoodieKey}s for which locations are fetched
   * @param context         instance of {@link HoodieEngineContext} to use
   * @param hoodieTable instance of {@link HoodieTable} of interest
   * @param parallelism parallelism to use
   * @return {@link JavaPairRDD} of {@link HoodieKey} and {@link HoodieRecordLocation}
   */
  protected JavaPairRDD<HoodieKey, HoodieRecordLocation> fetchRecordLocationsForAffectedPartitions(JavaRDD<HoodieKey> hoodieKeys,
                                                                                                   HoodieEngineContext context,
                                                                                                   HoodieTable<T, JavaRDD<HoodieRecord<T>>, JavaRDD<HoodieKey>, JavaRDD<WriteStatus>> hoodieTable,
                                                                                                   int parallelism) {
    List<String> affectedPartitionPathList = hoodieKeys.map(HoodieKey::getPartitionPath).distinct().collect();
    List<Pair<String, HoodieBaseFile>> latestBaseFiles = getLatestBaseFilesForAllPartitions(affectedPartitionPathList, context, hoodieTable);
    return fetchRecordLocations(context, hoodieTable, parallelism, latestBaseFiles);
  }

  protected JavaPairRDD<HoodieKey, HoodieRecordLocation> fetchRecordLocations(HoodieEngineContext context,
                                                                              HoodieTable<T, JavaRDD<HoodieRecord<T>>, JavaRDD<HoodieKey>, JavaRDD<WriteStatus>> hoodieTable,
                                                                              int parallelism,
                                                                              List<Pair<String, HoodieBaseFile>> baseFiles) {
    JavaSparkContext jsc = HoodieSparkEngineContext.getSparkContext(context);
    int fetchParallelism = Math.max(1, Math.max(baseFiles.size(), parallelism));
    return jsc.parallelize(baseFiles, fetchParallelism)
        .flatMapToPair(partitionPathBaseFile -> new HoodieKeyLocationFetchHandle(config, hoodieTable, partitionPathBaseFile).locations());
  }
}