com.uber.hoodie.hadoop.realtime.RealtimeUnmergedRecordReader.java Source code

Introduction

Here is the source code for com.uber.hoodie.hadoop.realtime.RealtimeUnmergedRecordReader.java

Source

/*
 * 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 com.uber.hoodie.hadoop.realtime;

import com.uber.hoodie.common.table.log.HoodieUnMergedLogRecordScanner;
import com.uber.hoodie.common.util.DefaultSizeEstimator;
import com.uber.hoodie.common.util.FSUtils;
import com.uber.hoodie.common.util.queue.BoundedInMemoryExecutor;
import com.uber.hoodie.common.util.queue.BoundedInMemoryQueueProducer;
import com.uber.hoodie.common.util.queue.FunctionBasedQueueProducer;
import com.uber.hoodie.common.util.queue.IteratorBasedQueueProducer;
import com.uber.hoodie.hadoop.RecordReaderValueIterator;
import com.uber.hoodie.hadoop.SafeParquetRecordReaderWrapper;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Optional;
import org.apache.avro.generic.GenericRecord;
import org.apache.hadoop.io.ArrayWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.RecordReader;

class RealtimeUnmergedRecordReader extends AbstractRealtimeRecordReader
        implements RecordReader<NullWritable, ArrayWritable> {

    // Log Record unmerged scanner
    private final HoodieUnMergedLogRecordScanner logRecordScanner;

    // Parquet record reader
    private final RecordReader<NullWritable, ArrayWritable> parquetReader;

    // Parquet record iterator wrapper for the above reader
    private final RecordReaderValueIterator<NullWritable, ArrayWritable> parquetRecordsIterator;

    // Executor that runs the above producers in parallel
    private final BoundedInMemoryExecutor<ArrayWritable, ArrayWritable, ?> executor;

    // Iterator for the buffer consumer
    private final Iterator<ArrayWritable> iterator;

    /**
     * Construct a Unmerged record reader that parallely consumes both parquet and log records and buffers for upstream
     * clients to consume
     *
     * @param split      File split
     * @param job        Job Configuration
     * @param realReader Parquet Reader
     */
    public RealtimeUnmergedRecordReader(HoodieRealtimeFileSplit split, JobConf job,
            RecordReader<NullWritable, ArrayWritable> realReader) {
        super(split, job);
        this.parquetReader = new SafeParquetRecordReaderWrapper(realReader);
        // Iterator for consuming records from parquet file
        this.parquetRecordsIterator = new RecordReaderValueIterator<>(this.parquetReader);
        this.executor = new BoundedInMemoryExecutor<>(getMaxCompactionMemoryInBytes(), getParallelProducers(),
                Optional.empty(), x -> x, new DefaultSizeEstimator<>());
        // Consumer of this record reader
        this.iterator = this.executor.getQueue().iterator();
        this.logRecordScanner = new HoodieUnMergedLogRecordScanner(
                FSUtils.getFs(split.getPath().toString(), jobConf), split.getBasePath(), split.getDeltaFilePaths(),
                getReaderSchema(), split.getMaxCommitTime(),
                Boolean.valueOf(jobConf.get(COMPACTION_LAZY_BLOCK_READ_ENABLED_PROP,
                        DEFAULT_COMPACTION_LAZY_BLOCK_READ_ENABLED)),
                false, jobConf.getInt(MAX_DFS_STREAM_BUFFER_SIZE_PROP, DEFAULT_MAX_DFS_STREAM_BUFFER_SIZE),
                record -> {
                    // convert Hoodie log record to Hadoop AvroWritable and buffer
                    GenericRecord rec = (GenericRecord) record.getData().getInsertValue(getReaderSchema()).get();
                    ArrayWritable aWritable = (ArrayWritable) avroToArrayWritable(rec, getWriterSchema());
                    this.executor.getQueue().insertRecord(aWritable);
                });
        // Start reading and buffering
        this.executor.startProducers();
    }

    /**
     * Setup log and parquet reading in parallel. Both write to central buffer.
     */
    @SuppressWarnings("unchecked")
    private List<BoundedInMemoryQueueProducer<ArrayWritable>> getParallelProducers() {
        List<BoundedInMemoryQueueProducer<ArrayWritable>> producers = new ArrayList<>();
        producers.add(new FunctionBasedQueueProducer<>(buffer -> {
            logRecordScanner.scan();
            return null;
        }));
        producers.add(new IteratorBasedQueueProducer<>(parquetRecordsIterator));
        return producers;
    }

    @Override
    public boolean next(NullWritable key, ArrayWritable value) throws IOException {
        if (!iterator.hasNext()) {
            return false;
        }
        // Copy from buffer iterator and set to passed writable
        value.set(iterator.next().get());
        return true;
    }

    @Override
    public NullWritable createKey() {
        return parquetReader.createKey();
    }

    @Override
    public ArrayWritable createValue() {
        return parquetReader.createValue();
    }

    @Override
    public long getPos() throws IOException {
        //TODO: vb - No logical way to represent parallel stream pos in a single long.
        // Should we just return invalid (-1). Where is it used ?
        return 0;
    }

    @Override
    public void close() throws IOException {
        this.parquetRecordsIterator.close();
        this.executor.shutdownNow();
    }

    @Override
    public float getProgress() throws IOException {
        return Math.min(parquetReader.getProgress(), logRecordScanner.getProgress());
    }
}