/**
 * 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.tez.runtime.library.common.writers;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import static org.mockito.Matchers.any;
import static org.mockito.Matchers.anyListOf;
import static org.mockito.Matchers.eq;
import static org.mockito.Mockito.atLeast;
import static org.mockito.Mockito.atMost;
import static org.mockito.Mockito.doAnswer;
import static org.mockito.Mockito.doReturn;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.never;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;

import java.io.ByteArrayInputStream;
import java.io.DataInputStream;
import java.io.InputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.Arrays;
import java.util.BitSet;
import java.util.Collection;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Random;
import java.util.Set;
import java.util.UUID;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import com.google.protobuf.ByteString;
import org.apache.hadoop.fs.CommonConfigurationKeys;
import org.apache.hadoop.fs.permission.FsAction;
import org.apache.tez.dag.api.TezConfiguration;
import org.apache.tez.runtime.api.TaskFailureType;
import org.apache.tez.runtime.api.events.VertexManagerEvent;
import org.apache.tez.runtime.library.common.Constants;
import org.apache.tez.runtime.library.common.writers.UnorderedPartitionedKVWriter.SpillInfo;
import org.apache.tez.runtime.library.shuffle.impl.ShuffleUserPayloads.VertexManagerEventPayloadProto;
import org.apache.tez.runtime.library.utils.DATA_RANGE_IN_MB;
import org.roaringbitmap.RoaringBitmap;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.hadoop.conf.Configurable;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.DataInputBuffer;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.compress.CompressionCodec;
import org.apache.hadoop.io.compress.DefaultCodec;
import org.apache.hadoop.yarn.api.records.ApplicationId;
import org.apache.tez.common.TezCommonUtils;
import org.apache.tez.common.TezRuntimeFrameworkConfigs;
import org.apache.tez.common.TezUtilsInternal;
import org.apache.tez.common.counters.TaskCounter;
import org.apache.tez.common.counters.TezCounter;
import org.apache.tez.common.counters.TezCounters;
import org.apache.tez.runtime.api.Event;
import org.apache.tez.runtime.api.OutputContext;
import org.apache.tez.runtime.api.events.CompositeDataMovementEvent;
import org.apache.tez.runtime.library.api.Partitioner;
import org.apache.tez.runtime.library.api.TezRuntimeConfiguration;
import org.apache.tez.runtime.library.api.TezRuntimeConfiguration.ReportPartitionStats;
import org.apache.tez.runtime.library.common.sort.impl.IFile;
import org.apache.tez.runtime.library.common.sort.impl.TezIndexRecord;
import org.apache.tez.runtime.library.common.sort.impl.TezSpillRecord;
import org.apache.tez.runtime.library.common.task.local.output.TezTaskOutput;
import org.apache.tez.runtime.library.common.task.local.output.TezTaskOutputFiles;
import org.apache.tez.runtime.library.partitioner.HashPartitioner;
import org.apache.tez.runtime.library.shuffle.impl.ShuffleUserPayloads.DataMovementEventPayloadProto;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;

import com.google.common.collect.LinkedListMultimap;
import com.google.common.collect.Multimap;
import com.google.common.collect.Sets;
import org.mockito.ArgumentCaptor;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;

@RunWith(value = Parameterized.class)
public class TestUnorderedPartitionedKVWriter {

  private static final Logger LOG = LoggerFactory.getLogger(TestUnorderedPartitionedKVWriter.class);

  private static final String HOST_STRING = "localhost";
  private static final int SHUFFLE_PORT = 4000;

  private static String testTmpDir = System.getProperty("test.build.data", "/tmp");
  private static final Path TEST_ROOT_DIR = new Path(testTmpDir,
      TestUnorderedPartitionedKVWriter.class.getSimpleName());
  private static FileSystem localFs;

  private boolean shouldCompress;
  private ReportPartitionStats reportPartitionStats;
  private Configuration defaultConf = new Configuration();

  public TestUnorderedPartitionedKVWriter(boolean shouldCompress,
      ReportPartitionStats reportPartitionStats) {
    this.shouldCompress = shouldCompress;
    this.reportPartitionStats = reportPartitionStats;
  }

  @SuppressWarnings("deprecation")
  @Parameterized.Parameters(name = "test[{0}, {1}]")
  public static Collection<Object[]> data() {
    Object[][] data = new Object[][] {
        { false, ReportPartitionStats.DISABLED },
        { false, ReportPartitionStats.ENABLED },
        { false, ReportPartitionStats.NONE },
        { false, ReportPartitionStats.MEMORY_OPTIMIZED },
        { false, ReportPartitionStats.PRECISE },
        { true, ReportPartitionStats.DISABLED },
        { true, ReportPartitionStats.ENABLED },
        { true, ReportPartitionStats.NONE },
        { true, ReportPartitionStats.MEMORY_OPTIMIZED },
        { true, ReportPartitionStats.PRECISE }};
    return Arrays.asList(data);
  }

  @Before
  public void setup() throws IOException {
    LOG.info("Setup. Using test dir: " + TEST_ROOT_DIR);
    localFs = FileSystem.getLocal(new Configuration());
    localFs.delete(TEST_ROOT_DIR, true);
    localFs.mkdirs(TEST_ROOT_DIR);
  }

  @After
  public void cleanup() throws IOException {
    LOG.info("CleanUp");
    localFs.delete(TEST_ROOT_DIR, true);
  }

  @Test(timeout = 10000)
  public void testBufferSizing() throws IOException {
    ApplicationId appId = ApplicationId.newInstance(10000000, 1);
    TezCounters counters = new TezCounters();
    String uniqueId = UUID.randomUUID().toString();
    String auxiliaryService = defaultConf.get(TezConfiguration.TEZ_AM_SHUFFLE_AUXILIARY_SERVICE_ID,
        TezConfiguration.TEZ_AM_SHUFFLE_AUXILIARY_SERVICE_ID_DEFAULT);
    OutputContext outputContext = createMockOutputContext(counters, appId, uniqueId, auxiliaryService);

    final int maxSingleBufferSizeBytes = 2047;
    final long sizePerBuffer = maxSingleBufferSizeBytes - 64 - maxSingleBufferSizeBytes % 4;
    Configuration conf = createConfiguration(outputContext, IntWritable.class, LongWritable.class,
        false, maxSingleBufferSizeBytes);

    int numOutputs = 10;

    UnorderedPartitionedKVWriter kvWriter = null;

    // Not enough memory so divide into 2 buffers.
    kvWriter = new UnorderedPartitionedKVWriterForTest(outputContext, conf, numOutputs, 2048);
    assertEquals(2, kvWriter.numBuffers);
    assertEquals(1024, kvWriter.sizePerBuffer);
    assertEquals(1024, kvWriter.lastBufferSize);
    assertEquals(1, kvWriter.numInitializedBuffers);
    assertEquals(1, kvWriter.spillLimit);

    // allocate exact
    kvWriter = new UnorderedPartitionedKVWriterForTest(outputContext, conf, numOutputs,
        maxSingleBufferSizeBytes * 3);
    assertEquals(3, kvWriter.numBuffers);
    assertEquals(sizePerBuffer, kvWriter.sizePerBuffer);
    assertEquals(sizePerBuffer, kvWriter.lastBufferSize);
    assertEquals(1, kvWriter.numInitializedBuffers);
    assertEquals(1, kvWriter.spillLimit);

    // under allocate
    kvWriter = new UnorderedPartitionedKVWriterForTest(outputContext, conf, numOutputs,
        maxSingleBufferSizeBytes * 2 + maxSingleBufferSizeBytes / 2);
    assertEquals(2, kvWriter.numBuffers);
    assertEquals(sizePerBuffer, kvWriter.sizePerBuffer);
    assertEquals(sizePerBuffer, kvWriter.lastBufferSize);
    assertEquals(1, kvWriter.numInitializedBuffers);
    assertEquals(1, kvWriter.spillLimit);

    // over allocate
    kvWriter = new UnorderedPartitionedKVWriterForTest(outputContext, conf, numOutputs,
        maxSingleBufferSizeBytes * 2 + maxSingleBufferSizeBytes / 2 + 1);
    assertEquals(3, kvWriter.numBuffers);
    assertEquals(sizePerBuffer, kvWriter.sizePerBuffer);
    assertEquals(maxSingleBufferSizeBytes / 2 + 1, kvWriter.lastBufferSize);
    assertEquals(1, kvWriter.numInitializedBuffers);
    assertEquals(1, kvWriter.spillLimit);

    // spill limit 1.
    kvWriter = new UnorderedPartitionedKVWriterForTest(outputContext, conf, numOutputs,
        4 * maxSingleBufferSizeBytes + 1);
    assertEquals(4, kvWriter.numBuffers);
    assertEquals(sizePerBuffer, kvWriter.sizePerBuffer);
    assertEquals(sizePerBuffer, kvWriter.lastBufferSize);
    assertEquals(1, kvWriter.numInitializedBuffers);
    assertEquals(1, kvWriter.spillLimit);

    // spill limit 2.
    conf.setInt(
        TezRuntimeConfiguration.TEZ_RUNTIME_UNORDERED_PARTITIONED_KVWRITER_BUFFER_MERGE_PERCENT,
        50);
    kvWriter = new UnorderedPartitionedKVWriterForTest(outputContext, conf, numOutputs,
        4 * maxSingleBufferSizeBytes + 1);
    assertEquals(4, kvWriter.numBuffers);
    assertEquals(sizePerBuffer, kvWriter.sizePerBuffer);
    assertEquals(sizePerBuffer, kvWriter.lastBufferSize);
    assertEquals(1, kvWriter.numInitializedBuffers);
    assertEquals(2, kvWriter.spillLimit);

    // Available memory is less than buffer size.
    conf.unset(TezRuntimeConfiguration.TEZ_RUNTIME_UNORDERED_OUTPUT_MAX_PER_BUFFER_SIZE_BYTES);
    kvWriter = new UnorderedPartitionedKVWriterForTest(outputContext, conf, numOutputs,
        2048);
    assertEquals(2, kvWriter.numBuffers);
    assertEquals(1024, kvWriter.sizePerBuffer);
    assertEquals(1024, kvWriter.lastBufferSize);
    assertEquals(1, kvWriter.numInitializedBuffers);
    assertEquals(1, kvWriter.spillLimit);
  }

  @Test(timeout = 10000)
  public void testNoSpill() throws IOException, InterruptedException {
    baseTest(10, 10, null, shouldCompress, -1, 0);
  }

  @Test(timeout = 10000)
  public void testSingleSpill() throws IOException, InterruptedException {
    baseTest(50, 10, null, shouldCompress, -1, 0);
  }

  @Test(timeout = 10000)
  public void testMultipleSpills() throws IOException, InterruptedException {
    baseTest(200, 10, null, shouldCompress, -1, 0);
  }

  @Test(timeout = 10000)
  public void testMultipleSpillsWithSmallBuffer() throws IOException, InterruptedException {
    // numBuffers is much higher than available threads.
    baseTest(200, 10, null, shouldCompress, 512, 0, 9600, false);
  }

  @Test(timeout = 10000)
  public void testMergeBuffersAndSpill() throws IOException, InterruptedException {
    baseTest(200, 10, null, shouldCompress, 2048, 10);
  }

  @Test(timeout = 10000)
  public void testNoRecords() throws IOException, InterruptedException {
    baseTest(0, 10, null, shouldCompress, -1, 0);
  }

  @Test(timeout = 10000)
  public void testNoRecords_SinglePartition() throws IOException, InterruptedException {
    // skipBuffers
    baseTest(0, 1, null, shouldCompress, -1, 0, 2048, false);
    // Check with data via events
    baseTest(0, 1, null, shouldCompress, -1, 0, 2048, true);
  }

  @Test(timeout = 10000)
  public void testSkippedPartitions() throws IOException, InterruptedException {
    baseTest(200, 10, Sets.newHashSet(2, 5), shouldCompress, -1, 0);
  }

  @Test(timeout = 10000)
  public void testNoSpill_SinglePartition() throws IOException, InterruptedException {
    baseTest(10, 1, null, shouldCompress, -1, 0);
  }

  @Test(timeout = 10000)
  public void testSpill_SinglePartition() throws IOException, InterruptedException {
    baseTest(1000, 1, null, shouldCompress, -1, 0, 2048, true);
  }

  @Test(timeout = 10000)
  public void testRandomText() throws IOException, InterruptedException {
    textTest(100, 10, 2048, 0, 0, 0, false, true);
  }

  @Test(timeout = 10000)
  public void testLargeKeys() throws IOException, InterruptedException {
    textTest(0, 10, 2048, 10, 0, 0, false, true);
  }

  @Test(timeout = 10000)
  public void testLargevalues() throws IOException, InterruptedException {
    textTest(0, 10, 2048, 0, 10, 0, false, true);
  }

  @Test(timeout = 10000)
  public void testLargeKvPairs() throws IOException, InterruptedException {
    textTest(0, 10, 2048, 0, 0, 10, false, true);
  }

  @Test(timeout = 10000)
  public void testTextMixedRecords() throws IOException, InterruptedException {
    textTest(100, 10, 2048, 10, 10, 10, false, true);
  }

  @Test(timeout = 10000000)
  public void testRandomTextWithoutFinalMerge() throws IOException, InterruptedException {
    textTest(100, 10, 2048, 0, 0, 0, false, false);
  }

  @Test(timeout = 10000)
  public void testLargeKeysWithoutFinalMerge() throws IOException, InterruptedException {
    textTest(0, 10, 2048, 10, 0, 0, false, false);
  }

  @Test(timeout = 10000)
  public void testLargevaluesWithoutFinalMerge() throws IOException, InterruptedException {
    textTest(0, 10, 2048, 0, 10, 0, false, false);
  }

  @Test(timeout = 10000)
  public void testLargeKvPairsWithoutFinalMerge() throws IOException, InterruptedException {
    textTest(0, 10, 2048, 0, 0, 10, false, false);
  }

  @Test(timeout = 10000)
  public void testTextMixedRecordsWithoutFinalMerge() throws IOException, InterruptedException {
    textTest(100, 10, 2048, 10, 10, 10, false, false);
  }

  public void textTest(int numRegularRecords, int numPartitions, long availableMemory,
      int numLargeKeys, int numLargevalues, int numLargeKvPairs,
      boolean pipeliningEnabled, boolean isFinalMergeEnabled) throws IOException,
      InterruptedException {
    Partitioner partitioner = new HashPartitioner();
    ApplicationId appId = ApplicationId.newInstance(10000000, 1);
    TezCounters counters = new TezCounters();
    String uniqueId = UUID.randomUUID().toString();
    int dagId = 1;
    String auxiliaryService = defaultConf.get(TezConfiguration.TEZ_AM_SHUFFLE_AUXILIARY_SERVICE_ID,
        TezConfiguration.TEZ_AM_SHUFFLE_AUXILIARY_SERVICE_ID_DEFAULT);
    OutputContext outputContext = createMockOutputContext(counters, appId, uniqueId, auxiliaryService);
    Random random = new Random();

    Configuration conf = createConfiguration(outputContext, Text.class, Text.class, shouldCompress,
        -1, HashPartitioner.class);
    conf.setBoolean(TezRuntimeConfiguration.TEZ_RUNTIME_PIPELINED_SHUFFLE_ENABLED, pipeliningEnabled);
    conf.setBoolean(TezRuntimeConfiguration.TEZ_RUNTIME_ENABLE_FINAL_MERGE_IN_OUTPUT, isFinalMergeEnabled);

    CompressionCodec codec = null;
    if (shouldCompress) {
      codec = new DefaultCodec();
      ((Configurable) codec).setConf(conf);
    }

    int numRecordsWritten = 0;

    Map<Integer, Multimap<String, String>> expectedValues = new HashMap<Integer, Multimap<String, String>>();
    for (int i = 0; i < numPartitions; i++) {
      expectedValues.put(i, LinkedListMultimap.<String, String> create());
    }

    UnorderedPartitionedKVWriter kvWriter = new UnorderedPartitionedKVWriterForTest(outputContext,
        conf, numPartitions, availableMemory);

    int sizePerBuffer = kvWriter.sizePerBuffer;

    BitSet partitionsWithData = new BitSet(numPartitions);
    Text keyText = new Text();
    Text valText = new Text();
    for (int i = 0; i < numRegularRecords; i++) {
      String key = createRandomString(Math.abs(random.nextInt(10)));
      String val = createRandomString(Math.abs(random.nextInt(20)));
      keyText.set(key);
      valText.set(val);
      int partition = partitioner.getPartition(keyText, valText, numPartitions);
      partitionsWithData.set(partition);
      expectedValues.get(partition).put(key, val);
      kvWriter.write(keyText, valText);
      numRecordsWritten++;
    }

    // Write Large key records
    for (int i = 0; i < numLargeKeys; i++) {
      String key = createRandomString(sizePerBuffer + Math.abs(random.nextInt(100)));
      String val = createRandomString(Math.abs(random.nextInt(20)));
      keyText.set(key);
      valText.set(val);
      int partition = partitioner.getPartition(keyText, valText, numPartitions);
      partitionsWithData.set(partition);
      expectedValues.get(partition).put(key, val);
      kvWriter.write(keyText, valText);
      numRecordsWritten++;
    }
    if (pipeliningEnabled) {
      verify(outputContext, times(numLargeKeys)).sendEvents(anyListOf(Event.class));
    }

    // Write Large val records
    for (int i = 0; i < numLargevalues; i++) {
      String key = createRandomString(Math.abs(random.nextInt(10)));
      String val = createRandomString(sizePerBuffer + Math.abs(random.nextInt(100)));
      keyText.set(key);
      valText.set(val);
      int partition = partitioner.getPartition(keyText, valText, numPartitions);
      partitionsWithData.set(partition);
      expectedValues.get(partition).put(key, val);
      kvWriter.write(keyText, valText);
      numRecordsWritten++;
    }
    if (pipeliningEnabled) {
      verify(outputContext, times(numLargevalues + numLargeKeys)).sendEvents(anyListOf(Event.class));
    }

    // Write records where key + val are large (but both can fit in the buffer individually)
    for (int i = 0; i < numLargeKvPairs; i++) {
      String key = createRandomString(sizePerBuffer / 2 + Math.abs(random.nextInt(100)));
      String val = createRandomString(sizePerBuffer / 2 + Math.abs(random.nextInt(100)));
      keyText.set(key);
      valText.set(val);
      int partition = partitioner.getPartition(keyText, valText, numPartitions);
      partitionsWithData.set(partition);
      expectedValues.get(partition).put(key, val);
      kvWriter.write(keyText, valText);
      numRecordsWritten++;
    }
    if (pipeliningEnabled) {
      verify(outputContext, times(numLargevalues + numLargeKeys + numLargeKvPairs))
          .sendEvents(anyListOf(Event.class));
    }

    List<Event> events = kvWriter.close();
    verify(outputContext, never()).reportFailure(any(TaskFailureType.class), any(Throwable.class), any(String.class));

    if (!pipeliningEnabled) {
      VertexManagerEvent vmEvent = null;
      for (Event event : events) {
        if (event instanceof VertexManagerEvent) {
          assertNull(vmEvent);
          vmEvent = (VertexManagerEvent) event;
        }
      }
      VertexManagerEventPayloadProto vmEventPayload =
        VertexManagerEventPayloadProto.parseFrom(
          ByteString.copyFrom(vmEvent.getUserPayload().asReadOnlyBuffer()));
      assertEquals(numRecordsWritten, vmEventPayload.getNumRecord());
    }

    TezCounter outputLargeRecordsCounter = counters.findCounter(TaskCounter.OUTPUT_LARGE_RECORDS);
    assertEquals(numLargeKeys + numLargevalues + numLargeKvPairs,
        outputLargeRecordsCounter.getValue());

    if (pipeliningEnabled || !isFinalMergeEnabled) {
      // verify spill data files and index file exist
      for (int i = 0; i < kvWriter.numSpills.get(); i++) {
        assertTrue(localFs.exists(kvWriter.outputFileHandler.getSpillFileForWrite(i, 0)));
        assertTrue(localFs.exists(kvWriter.outputFileHandler.getSpillIndexFileForWrite(i, 0)));
      }
      return;
    }

    // Validate the events
    assertEquals(2, events.size());

    assertTrue(events.get(0) instanceof VertexManagerEvent);
    VertexManagerEvent vme = (VertexManagerEvent) events.get(0);
    verifyPartitionStats(vme, partitionsWithData);

    assertTrue(events.get(1) instanceof CompositeDataMovementEvent);
    CompositeDataMovementEvent cdme = (CompositeDataMovementEvent) events.get(1);
    assertEquals(0, cdme.getSourceIndexStart());
    assertEquals(numPartitions, cdme.getCount());
    DataMovementEventPayloadProto eventProto = DataMovementEventPayloadProto.parseFrom(
        ByteString.copyFrom(cdme.getUserPayload()));
    assertFalse(eventProto.hasData());
    BitSet emptyPartitionBits = null;
    if (partitionsWithData.cardinality() != numPartitions) {
      assertTrue(eventProto.hasEmptyPartitions());
      byte[] emptyPartitions = TezCommonUtils.decompressByteStringToByteArray(
          eventProto.getEmptyPartitions());
      emptyPartitionBits = TezUtilsInternal.fromByteArray(emptyPartitions);
      assertEquals(numPartitions - partitionsWithData.cardinality(),
          emptyPartitionBits.cardinality());
    } else {
      assertFalse(eventProto.hasEmptyPartitions());
      emptyPartitionBits = new BitSet(numPartitions);
    }
    assertEquals(HOST_STRING, eventProto.getHost());
    assertEquals(SHUFFLE_PORT, eventProto.getPort());
    assertEquals(uniqueId, eventProto.getPathComponent());

    // Verify the data
    // Verify the actual data
    TezTaskOutput taskOutput = new TezTaskOutputFiles(conf, uniqueId, dagId);
    Path outputFilePath = kvWriter.finalOutPath;
    Path spillFilePath = kvWriter.finalIndexPath;
    if (numRecordsWritten > 0) {
      assertTrue(localFs.exists(outputFilePath));
      assertTrue(localFs.exists(spillFilePath));
      checkPermissions(outputFilePath, spillFilePath);
    } else {
      return;
    }

    // Special case for 0 records.
    TezSpillRecord spillRecord = new TezSpillRecord(spillFilePath, conf);
    DataInputBuffer keyBuffer = new DataInputBuffer();
    DataInputBuffer valBuffer = new DataInputBuffer();
    Text keyDeser = new Text();
    Text valDeser = new Text();
    for (int i = 0; i < numPartitions; i++) {
      if (emptyPartitionBits.get(i)) {
        continue;
      }
      TezIndexRecord indexRecord = spillRecord.getIndex(i);
      FSDataInputStream inStream = FileSystem.getLocal(conf).open(outputFilePath);
      inStream.seek(indexRecord.getStartOffset());
      IFile.Reader reader = new IFile.Reader(inStream, indexRecord.getPartLength(), codec, null,
          null, false, 0, -1);
      while (reader.nextRawKey(keyBuffer)) {
        reader.nextRawValue(valBuffer);
        keyDeser.readFields(keyBuffer);
        valDeser.readFields(valBuffer);
        int partition = partitioner.getPartition(keyDeser, valDeser, numPartitions);
        assertTrue(expectedValues.get(partition).remove(keyDeser.toString(), valDeser.toString()));
      }
      inStream.close();
    }
    for (int i = 0; i < numPartitions; i++) {
      assertEquals(0, expectedValues.get(i).size());
      expectedValues.remove(i);
    }
    assertEquals(0, expectedValues.size());
  }

  private int[] getPartitionStats(VertexManagerEvent vme) throws IOException {
    RoaringBitmap partitionStats = new RoaringBitmap();
    VertexManagerEventPayloadProto
        payload = VertexManagerEventPayloadProto
        .parseFrom(ByteString.copyFrom(vme.getUserPayload()));
    if (!reportPartitionStats.isEnabled()) {
      assertFalse(payload.hasPartitionStats());
      assertFalse(payload.hasDetailedPartitionStats());
      return null;
    }
    if (reportPartitionStats.isPrecise()) {
      assertTrue(payload.hasDetailedPartitionStats());
      List<Integer> sizeInMBList =
          payload.getDetailedPartitionStats().getSizeInMbList();
      int[] stats = new int[sizeInMBList.size()];
      for (int i=0; i<sizeInMBList.size(); i++) {
        stats[i] += sizeInMBList.get(i);
      }
      return stats;
    } else {
      assertTrue(payload.hasPartitionStats());
      ByteString compressedPartitionStats = payload.getPartitionStats();
      byte[] rawData = TezCommonUtils.decompressByteStringToByteArray(
          compressedPartitionStats);
      ByteArrayInputStream bin = new ByteArrayInputStream(rawData);
      partitionStats.deserialize(new DataInputStream(bin));
      int[] stats = new int[partitionStats.getCardinality()];
      Iterator<Integer> it = partitionStats.iterator();
      final DATA_RANGE_IN_MB[] RANGES = DATA_RANGE_IN_MB.values();
      final int RANGE_LEN = RANGES.length;
      while (it.hasNext()) {
        int pos = it.next();
        int index = ((pos) / RANGE_LEN);
        int rangeIndex = ((pos) % RANGE_LEN);
        if (RANGES[rangeIndex].getSizeInMB() > 0) {
          stats[index] += RANGES[rangeIndex].getSizeInMB();
        }
      }
      return stats;
    }
  }

  private void verifyPartitionStats(VertexManagerEvent vme,
      BitSet expectedPartitionsWithData) throws IOException {
    int[] stats = getPartitionStats(vme);
    if (stats == null) {
      return;
    }
    for (int i = 0; i < stats.length; i++) {
      // The stats should be greater than zero if and only if
      // the partition has data
      assertTrue(expectedPartitionsWithData.get(i) == (stats[i] > 0));
    }
  }

  @Test(timeout = 10000)
  public void testNoSpill_WithPipelinedShuffle() throws IOException, InterruptedException {
    baseTestWithPipelinedTransfer(10, 10, null, shouldCompress);
  }

  @Test(timeout = 10000)
  public void testSingleSpill_WithPipelinedShuffle() throws IOException, InterruptedException {
    baseTestWithPipelinedTransfer(50, 10, null, shouldCompress);
  }

  @Test(timeout = 10000)
  public void testMultipleSpills_WithPipelinedShuffle() throws IOException, InterruptedException {
    baseTestWithPipelinedTransfer(200, 10, null, shouldCompress);
  }

  @Test(timeout = 10000)
  public void testNoRecords_WithPipelinedShuffle() throws IOException, InterruptedException {
    baseTestWithPipelinedTransfer(0, 10, null, shouldCompress);
  }

  @Test(timeout = 10000)
  public void testNoRecords_SinglePartition_WithPipelinedShuffle() throws IOException, InterruptedException {
    // skipBuffers
    baseTestWithPipelinedTransfer(0, 1, null, shouldCompress);
  }

  @Test(timeout = 10000)
  public void testSkippedPartitions_WithPipelinedShuffle() throws IOException, InterruptedException {
    baseTestWithPipelinedTransfer(200, 10, Sets.newHashSet(2, 5), shouldCompress);
  }

  @Test(timeout = 10000)
  public void testLargeKvPairs_WithPipelinedShuffle() throws IOException, InterruptedException {
    textTest(0, 10, 2048, 10, 20, 50, true, false);
  }


  @SuppressWarnings("unchecked")
  private void baseTestWithPipelinedTransfer(int numRecords, int numPartitions, Set<Integer>
      skippedPartitions, boolean shouldCompress) throws IOException, InterruptedException {

    PartitionerForTest partitioner = new PartitionerForTest();
    ApplicationId appId = ApplicationId.newInstance(10000000, 1);
    TezCounters counters = new TezCounters();
    String uniqueId = UUID.randomUUID().toString();
    int dagId = 1;
    String auxiliaryService = defaultConf.get(TezConfiguration.TEZ_AM_SHUFFLE_AUXILIARY_SERVICE_ID,
        TezConfiguration.TEZ_AM_SHUFFLE_AUXILIARY_SERVICE_ID_DEFAULT);
    OutputContext outputContext = createMockOutputContext(counters, appId, uniqueId, auxiliaryService);

    Configuration conf = createConfiguration(outputContext, IntWritable.class, LongWritable.class,
        shouldCompress, -1);
    conf.setBoolean(TezRuntimeConfiguration
        .TEZ_RUNTIME_ENABLE_FINAL_MERGE_IN_OUTPUT, false);
    conf.setBoolean(TezRuntimeConfiguration
        .TEZ_RUNTIME_PIPELINED_SHUFFLE_ENABLED, true);

    CompressionCodec codec = null;
    if (shouldCompress) {
      codec = new DefaultCodec();
      ((Configurable) codec).setConf(conf);
    }

    int numOutputs = numPartitions;
    long availableMemory = 2048;
    int numRecordsWritten = 0;

    UnorderedPartitionedKVWriter kvWriter = new UnorderedPartitionedKVWriterForTest(outputContext,
        conf, numOutputs, availableMemory);

    int sizePerBuffer = kvWriter.sizePerBuffer;
    int sizePerRecord = 4 + 8; // IntW + LongW
    int sizePerRecordWithOverhead = sizePerRecord + 12; // Record + META_OVERHEAD

    BitSet partitionsWithData = new BitSet(numPartitions);
    IntWritable intWritable = new IntWritable();
    LongWritable longWritable = new LongWritable();
    for (int i = 0; i < numRecords; i++) {
      intWritable.set(i);
      longWritable.set(i);
      int partition = partitioner.getPartition(intWritable, longWritable, numOutputs);
      if (skippedPartitions != null && skippedPartitions.contains(partition)) {
        continue;
      }
      partitionsWithData.set(partition);
      kvWriter.write(intWritable, longWritable);
      numRecordsWritten++;
    }

    int recordsPerBuffer = sizePerBuffer / sizePerRecordWithOverhead;
    int numExpectedSpills = numRecordsWritten / recordsPerBuffer;

    ArgumentCaptor<List> eventCaptor = ArgumentCaptor.forClass(List.class);
    List<Event> lastEvents = kvWriter.close();

    if (numPartitions == 1) {
      assertEquals(false, kvWriter.skipBuffers);
    }

    //no events are sent to kvWriter upon close with pipelining
    assertTrue(lastEvents.size() == 0);
    verify(outputContext, atLeast(numExpectedSpills)).sendEvents(eventCaptor.capture());
    int numOfCapturedEvents = eventCaptor.getAllValues().size();
    lastEvents = eventCaptor.getAllValues().get(numOfCapturedEvents - 1);
    VertexManagerEvent VMEvent = (VertexManagerEvent)lastEvents.get(0);

    for (int i=0; i<numOfCapturedEvents; i++) {
      List<Event> events = eventCaptor.getAllValues().get(i);
      if (i < numOfCapturedEvents - 1) {
        assertTrue(events.size() == 1);
        assertTrue(events.get(0) instanceof CompositeDataMovementEvent);
      } else {
        assertTrue(events.size() == 2);
        assertTrue(events.get(0) instanceof VertexManagerEvent);
        assertTrue(events.get(1) instanceof CompositeDataMovementEvent);
      }
    }
    verifyPartitionStats(VMEvent, partitionsWithData);

    verify(outputContext, never()).reportFailure(any(TaskFailureType.class),
        any(Throwable.class), any(String.class));

    assertNull(kvWriter.currentBuffer);
    assertEquals(0, kvWriter.availableBuffers.size());

    // Verify the counters
    TezCounter outputRecordBytesCounter =
        counters.findCounter(TaskCounter.OUTPUT_BYTES);
    TezCounter outputRecordsCounter =
        counters.findCounter(TaskCounter.OUTPUT_RECORDS);
    TezCounter outputBytesWithOverheadCounter =
        counters.findCounter(TaskCounter.OUTPUT_BYTES_WITH_OVERHEAD);
    TezCounter fileOutputBytesCounter =
        counters.findCounter(TaskCounter.OUTPUT_BYTES_PHYSICAL);
    TezCounter spilledRecordsCounter =
        counters.findCounter(TaskCounter.SPILLED_RECORDS);
    TezCounter additionalSpillBytesWritternCounter = counters
        .findCounter(TaskCounter.ADDITIONAL_SPILLS_BYTES_WRITTEN);
    TezCounter additionalSpillBytesReadCounter = counters
        .findCounter(TaskCounter.ADDITIONAL_SPILLS_BYTES_READ);
    TezCounter numAdditionalSpillsCounter = counters
        .findCounter(TaskCounter.ADDITIONAL_SPILL_COUNT);
    assertEquals(numRecordsWritten * sizePerRecord,
        outputRecordBytesCounter.getValue());
    assertEquals(numRecordsWritten, outputRecordsCounter.getValue());
    assertEquals(numRecordsWritten * sizePerRecordWithOverhead,
        outputBytesWithOverheadCounter.getValue());
    long fileOutputBytes = fileOutputBytesCounter.getValue();
    if (numRecordsWritten > 0) {
      assertTrue(fileOutputBytes > 0);
      if (!shouldCompress) {
        assertTrue(fileOutputBytes > outputRecordBytesCounter.getValue());
      }
    } else {
      assertEquals(0, fileOutputBytes);
    }
    // due to multiple threads, buffers could be merged in chunks in scheduleSpill.
    assertTrue(recordsPerBuffer * numExpectedSpills >= spilledRecordsCounter.getValue());
    long additionalSpillBytesWritten =
        additionalSpillBytesWritternCounter.getValue();
    long additionalSpillBytesRead = additionalSpillBytesReadCounter.getValue();

    //No additional spill bytes written when final merge is disabled.
    assertEquals(additionalSpillBytesWritten, 0);

    //No additional spills when final merge is disabled.
    assertTrue(additionalSpillBytesWritten == additionalSpillBytesRead);

    //No additional spills when final merge is disabled.
    assertEquals(numAdditionalSpillsCounter.getValue(), 0);

    assertTrue(lastEvents.size() > 0);
    //Get the last event
    int index = lastEvents.size() - 1;
    assertTrue(lastEvents.get(index) instanceof CompositeDataMovementEvent);
    CompositeDataMovementEvent cdme =
        (CompositeDataMovementEvent)lastEvents.get(index);
    assertEquals(0, cdme.getSourceIndexStart());
    assertEquals(numOutputs, cdme.getCount());
    DataMovementEventPayloadProto eventProto =
        DataMovementEventPayloadProto.parseFrom(
            ByteString.copyFrom(cdme.getUserPayload()));
    //Ensure that this is the last event
    assertTrue(eventProto.getLastEvent());
    verifyEmptyPartitions(eventProto, numRecordsWritten, numPartitions, skippedPartitions);

    verify(outputContext, atLeast(1)).notifyProgress();

    // Verify if all spill files are available.
    TezTaskOutput taskOutput = new TezTaskOutputFiles(conf, uniqueId, dagId);

    if (numRecordsWritten > 0) {
      int numSpills = kvWriter.numSpills.get();
      for (int i = 0; i < numSpills; i++) {
        Path outputFile = taskOutput.getSpillFileForWrite(i, 10);
        Path indexFile = taskOutput.getSpillIndexFileForWrite(i, 10);
        assertTrue(localFs.exists(outputFile));
        assertTrue(localFs.exists(indexFile));
        checkPermissions(outputFile, indexFile);
      }
    } else {
      return;
    }
  }

  private void checkPermissions(Path outputFile, Path indexFile) throws IOException {
    assertEquals("Incorrect output permissions (user)", FsAction.READ_WRITE,
        localFs.getFileStatus(outputFile).getPermission().getUserAction());
    assertEquals("Incorrect output permissions (group)", FsAction.READ,
        localFs.getFileStatus(outputFile).getPermission().getGroupAction());
    assertEquals("Incorrect index permissions (user)", FsAction.READ_WRITE,
        localFs.getFileStatus(indexFile).getPermission().getUserAction());
    assertEquals("Incorrect index permissions (group)", FsAction.READ,
        localFs.getFileStatus(indexFile).getPermission().getGroupAction());
  }

  private void verifyEmptyPartitions(DataMovementEventPayloadProto eventProto,
      int numRecordsWritten, int numPartitions, Set<Integer> skippedPartitions)
      throws IOException {
    if (eventProto.hasEmptyPartitions()) {
      byte[] emptyPartitions = TezCommonUtils.decompressByteStringToByteArray(
          eventProto.getEmptyPartitions());
      BitSet emptyPartitionBits = TezUtilsInternal.fromByteArray(emptyPartitions);
      if (numRecordsWritten == 0) {
        assertEquals(numPartitions, emptyPartitionBits.cardinality());
      } else {
        if (skippedPartitions != null) {
          for (Integer e : skippedPartitions) {
            assertTrue(emptyPartitionBits.get(e));
          }
          assertEquals(skippedPartitions.size(), emptyPartitionBits.cardinality());
        }
      }
      if (emptyPartitionBits.cardinality() != numPartitions) {
        assertEquals(HOST_STRING, eventProto.getHost());
        assertEquals(SHUFFLE_PORT, eventProto.getPort());
        assertTrue(eventProto.hasPathComponent());
      } else {
        assertFalse(eventProto.hasHost());
        assertFalse(eventProto.hasPort());
        assertFalse(eventProto.hasPathComponent());
      }
    } else {
      assertEquals(HOST_STRING, eventProto.getHost());
      assertEquals(SHUFFLE_PORT, eventProto.getPort());
      assertTrue(eventProto.hasPathComponent());
    }
  }

  @Test(timeout = 10000)
  public void testNoSpill_WithFinalMergeDisabled() throws IOException, InterruptedException {
    baseTestWithFinalMergeDisabled(10, 10, null, shouldCompress);
  }

  @Test(timeout = 10000)
  public void testSingleSpill_WithFinalMergeDisabled() throws IOException, InterruptedException {
    baseTestWithFinalMergeDisabled(50, 10, null, shouldCompress);
  }

  @Test(timeout = 10000)
  public void testSinglePartition_WithFinalMergeDisabled() throws IOException, InterruptedException {
    baseTestWithFinalMergeDisabled(0, 1, null, shouldCompress);
  }

  @Test(timeout = 10000)
  public void testMultipleSpills_WithFinalMergeDisabled() throws IOException, InterruptedException {
    baseTestWithFinalMergeDisabled(200, 10, null, shouldCompress);
  }

  @Test(timeout = 10000)
  public void testNoRecords_WithFinalMergeDisabled() throws IOException, InterruptedException {
    baseTestWithFinalMergeDisabled(0, 10, null, shouldCompress);
  }

  @Test(timeout = 10000)
  public void testNoRecords_SinglePartition_WithFinalMergeDisabled() throws IOException, InterruptedException {
    baseTestWithFinalMergeDisabled(0, 1, null, shouldCompress);
  }

  @Test(timeout = 10000)
  public void testSkippedPartitions_WithFinalMergeDisabled() throws IOException, InterruptedException {
    baseTestWithFinalMergeDisabled(200, 10, Sets.newHashSet(2, 5), shouldCompress);
  }

  @SuppressWarnings("unchecked")
  private void baseTestWithFinalMergeDisabled(int numRecords, int numPartitions,
      Set<Integer> skippedPartitions, boolean shouldCompress) throws IOException, InterruptedException {

    PartitionerForTest partitioner = new PartitionerForTest();
    ApplicationId appId = ApplicationId.newInstance(10000000, 1);
    TezCounters counters = new TezCounters();
    String uniqueId = UUID.randomUUID().toString();
    int dagId = 1;
    String auxiliaryService = defaultConf.get(TezConfiguration.TEZ_AM_SHUFFLE_AUXILIARY_SERVICE_ID,
        TezConfiguration.TEZ_AM_SHUFFLE_AUXILIARY_SERVICE_ID_DEFAULT);
    OutputContext outputContext = createMockOutputContext(counters, appId, uniqueId, auxiliaryService);

    Configuration conf = createConfiguration(outputContext, IntWritable.class, LongWritable.class,
        shouldCompress, -1);
    conf.setBoolean(TezRuntimeConfiguration
        .TEZ_RUNTIME_ENABLE_FINAL_MERGE_IN_OUTPUT, false);
    conf.setBoolean(TezRuntimeConfiguration
        .TEZ_RUNTIME_PIPELINED_SHUFFLE_ENABLED, false);

    CompressionCodec codec = null;
    if (shouldCompress) {
      codec = new DefaultCodec();
      ((Configurable) codec).setConf(conf);
    }

    int numOutputs = numPartitions;
    long availableMemory = 2048;
    int numRecordsWritten = 0;

    UnorderedPartitionedKVWriter kvWriter = new UnorderedPartitionedKVWriterForTest(outputContext,
        conf, numOutputs, availableMemory);

    int sizePerBuffer = kvWriter.sizePerBuffer;
    int sizePerRecord = 4 + 8; // IntW + LongW
    int sizePerRecordWithOverhead = sizePerRecord + 12; // Record + META_OVERHEAD

    BitSet partitionsWithData = new BitSet(numPartitions);
    IntWritable intWritable = new IntWritable();
    LongWritable longWritable = new LongWritable();
    for (int i = 0; i < numRecords; i++) {
      intWritable.set(i);
      longWritable.set(i);
      int partition = partitioner.getPartition(intWritable, longWritable, numOutputs);
      if (skippedPartitions != null && skippedPartitions.contains(partition)) {
        continue;
      }
      partitionsWithData.set(partition);
      kvWriter.write(intWritable, longWritable);
      numRecordsWritten++;
    }

    int recordsPerBuffer = sizePerBuffer / sizePerRecordWithOverhead;
    int numExpectedSpills = numRecordsWritten / recordsPerBuffer;

    ArgumentCaptor<List> eventCaptor = ArgumentCaptor.forClass(List.class);
    List<Event> lastEvents = kvWriter.close();

    if (numPartitions == 1) {
      assertEquals(true, kvWriter.skipBuffers);
    }

    // max events sent are spills + one VM event. If there are no spills, atleast empty
    // partitions would be sent out finally.
    int spills = Math.max(1, kvWriter.numSpills.get());
    assertEquals((spills + 1), lastEvents.size()); //spills + VMEvent
    verify(outputContext, atMost(0)).sendEvents(eventCaptor.capture());

    for (int i=0; i<lastEvents.size(); i++) {
      Event event =lastEvents.get(i);
      if (event instanceof VertexManagerEvent) {
        //when there are no records, empty IFile with 6 bytes would be created which would add up
        // to stats.
        if (numRecordsWritten > 0) {
          verifyPartitionStats(((VertexManagerEvent) event), partitionsWithData);
        }
      }
    }

    verify(outputContext, never()).reportFailure(any(TaskFailureType.class),
        any(Throwable.class), any(String.class));

    assertNull(kvWriter.currentBuffer);
    assertEquals(0, kvWriter.availableBuffers.size());

    // Verify the counters
    TezCounter outputRecordBytesCounter =
        counters.findCounter(TaskCounter.OUTPUT_BYTES);
    TezCounter outputRecordsCounter =
        counters.findCounter(TaskCounter.OUTPUT_RECORDS);
    TezCounter outputBytesWithOverheadCounter =
        counters.findCounter(TaskCounter.OUTPUT_BYTES_WITH_OVERHEAD);
    TezCounter fileOutputBytesCounter =
        counters.findCounter(TaskCounter.OUTPUT_BYTES_PHYSICAL);
    TezCounter spilledRecordsCounter =
        counters.findCounter(TaskCounter.SPILLED_RECORDS);
    TezCounter additionalSpillBytesWritternCounter = counters
        .findCounter(TaskCounter.ADDITIONAL_SPILLS_BYTES_WRITTEN);
    TezCounter additionalSpillBytesReadCounter = counters
        .findCounter(TaskCounter.ADDITIONAL_SPILLS_BYTES_READ);
    TezCounter numAdditionalSpillsCounter = counters
        .findCounter(TaskCounter.ADDITIONAL_SPILL_COUNT);
    assertEquals(numRecordsWritten * sizePerRecord,
        outputRecordBytesCounter.getValue());
    assertEquals(numRecordsWritten, outputRecordsCounter.getValue());
    if (outputRecordsCounter.getValue() > 0) {
      assertEquals(numRecordsWritten * sizePerRecordWithOverhead,
          outputBytesWithOverheadCounter.getValue());
    } else {
      assertEquals(0, outputBytesWithOverheadCounter.getValue());
    }
    long fileOutputBytes = fileOutputBytesCounter.getValue();
    if (numRecordsWritten > 0) {
      assertTrue(fileOutputBytes > 0);
      if (!shouldCompress) {
        assertTrue("fileOutputBytes=" + fileOutputBytes + ", outputRecordBytes="
                +outputRecordBytesCounter.getValue(),
            fileOutputBytes > outputRecordBytesCounter.getValue());
      }
    } else {
      assertEquals(0, fileOutputBytes);
    }
    // due to multiple threads, buffers could be merged in chunks in scheduleSpill.
    assertTrue(recordsPerBuffer * numExpectedSpills >= spilledRecordsCounter.getValue());
    long additionalSpillBytesWritten = additionalSpillBytesWritternCounter.getValue();
    long additionalSpillBytesRead = additionalSpillBytesReadCounter.getValue();

    //No additional spill bytes written when final merge is disabled.
    assertEquals(additionalSpillBytesWritten, 0);

    //No additional spills when final merge is disabled.
    assertTrue(additionalSpillBytesWritten == additionalSpillBytesRead);

    //No additional spills when final merge is disabled.
    assertEquals(numAdditionalSpillsCounter.getValue(), 0);

    assertTrue(lastEvents.size() > 0);
    //Get the last event
    int index = lastEvents.size() - 1;
    assertTrue(lastEvents.get(index) instanceof CompositeDataMovementEvent);
    CompositeDataMovementEvent cdme =
        (CompositeDataMovementEvent)lastEvents.get(index);
    assertEquals(0, cdme.getSourceIndexStart());
    assertEquals(numOutputs, cdme.getCount());
    DataMovementEventPayloadProto eventProto =
        DataMovementEventPayloadProto.parseFrom(
            ByteString.copyFrom(cdme.getUserPayload()));

    verifyEmptyPartitions(eventProto, numRecordsWritten, numPartitions, skippedPartitions);

    if (outputRecordsCounter.getValue() > 0) {
      //Ensure that this is the last event
      assertTrue(eventProto.getLastEvent());
    }

    // Verify if all path components have spillIds when final merge is disabled
    Pattern mergePathComponentPattern = Pattern.compile("(.*)(_\\d+)");
    for(Event event : lastEvents) {
      if (!(event instanceof CompositeDataMovementEvent)) {
        continue;
      }
      cdme = (CompositeDataMovementEvent)event;
      eventProto = DataMovementEventPayloadProto.parseFrom(ByteString.copyFrom(cdme.getUserPayload()));

      assertEquals(false, eventProto.getPipelined());
      if (eventProto.hasPathComponent()) {
        //for final merge disabled cases, it should have _spillId
        Matcher matcher = mergePathComponentPattern.matcher(eventProto.getPathComponent());
        assertTrue("spill id should be present in path component " + eventProto.getPathComponent(), matcher.matches());
        assertEquals(2, matcher.groupCount());
        assertEquals(uniqueId, matcher.group(1));
        assertTrue("spill id should be present in path component", matcher.group(2) != null);
        Path outputPath = new Path(outputContext.getWorkDirs()[0],
            "output/" + eventProto.getPathComponent() + "/" + Constants.TEZ_RUNTIME_TASK_OUTPUT_FILENAME_STRING);
        Path indexPath = outputPath.suffix(Constants.TEZ_RUNTIME_TASK_OUTPUT_INDEX_SUFFIX_STRING);
        checkPermissions(outputPath, indexPath);
      } else {
        assertEquals(0, eventProto.getSpillId());
        if (outputRecordsCounter.getValue() > 0) {
          assertEquals(true, eventProto.getLastEvent());
        } else {
          byte[] emptyPartitions = TezCommonUtils.decompressByteStringToByteArray(eventProto
              .getEmptyPartitions());
          BitSet emptyPartitionBits = TezUtilsInternal.fromByteArray(emptyPartitions);
          assertEquals(numPartitions, emptyPartitionBits.cardinality());
        }
      }
    }


    verify(outputContext, atLeast(1)).notifyProgress();

    // Verify if all spill files are available.
    TezTaskOutput taskOutput = new TezTaskOutputFiles(conf, uniqueId, dagId);

    if (numRecordsWritten > 0) {
      int numSpills = kvWriter.numSpills.get();
      for (int i = 0; i < numSpills; i++) {
        assertTrue(localFs.exists(taskOutput.getSpillFileForWrite(i, 10)));
        assertTrue(localFs.exists(taskOutput.getSpillIndexFileForWrite(i, 10)));
      }
    } else {
      return;
    }
  }

  private void baseTest(int numRecords, int numPartitions, Set<Integer> skippedPartitions,
      boolean shouldCompress, int maxSingleBufferSizeBytes, int bufferMergePercent)
      throws IOException, InterruptedException {
    baseTest(numRecords, numPartitions, skippedPartitions, shouldCompress,
        maxSingleBufferSizeBytes, bufferMergePercent, 2048, false);
  }

  private void baseTest(int numRecords, int numPartitions, Set<Integer> skippedPartitions,
      boolean shouldCompress, int maxSingleBufferSizeBytes, int bufferMergePercent, int
      availableMemory, boolean dataViaEventEnabled)
          throws IOException, InterruptedException {
    PartitionerForTest partitioner = new PartitionerForTest();
    ApplicationId appId = ApplicationId.newInstance(10000000, 1);
    TezCounters counters = new TezCounters();
    String uniqueId = UUID.randomUUID().toString();
    int dagId = 1;
    String auxiliaryService = defaultConf.get(TezConfiguration.TEZ_AM_SHUFFLE_AUXILIARY_SERVICE_ID,
        TezConfiguration.TEZ_AM_SHUFFLE_AUXILIARY_SERVICE_ID_DEFAULT);
    OutputContext outputContext = createMockOutputContext(counters, appId, uniqueId, auxiliaryService);

    Configuration conf = createConfiguration(outputContext, IntWritable.class, LongWritable.class,
        shouldCompress, maxSingleBufferSizeBytes);
    conf.setInt(
        TezRuntimeConfiguration.TEZ_RUNTIME_UNORDERED_PARTITIONED_KVWRITER_BUFFER_MERGE_PERCENT,
        bufferMergePercent);
    conf.setBoolean(
        TezRuntimeConfiguration.TEZ_RUNTIME_TRANSFER_DATA_VIA_EVENTS_ENABLED,
        dataViaEventEnabled);

    CompressionCodec codec = null;
    if (shouldCompress) {
      codec = new DefaultCodec();
      ((Configurable) codec).setConf(conf);
    }

    int numOutputs = numPartitions;
    int numRecordsWritten = 0;

    Map<Integer, Multimap<Integer, Long>> expectedValues = new HashMap<Integer, Multimap<Integer, Long>>();
    for (int i = 0; i < numOutputs; i++) {
      expectedValues.put(i, LinkedListMultimap.<Integer, Long> create());
    }

    UnorderedPartitionedKVWriter kvWriter = new UnorderedPartitionedKVWriterForTest(outputContext,
        conf, numOutputs, availableMemory);

    int sizePerBuffer = kvWriter.sizePerBuffer;
    int sizePerRecord = 4 + 8; // IntW + LongW
    int sizePerRecordWithOverhead = sizePerRecord + 12; // Record + META_OVERHEAD

    IntWritable intWritable = new IntWritable();
    LongWritable longWritable = new LongWritable();
    BitSet partitionsWithData = new BitSet(numPartitions);
    for (int i = 0; i < numRecords; i++) {
      intWritable.set(i);
      longWritable.set(i);
      int partition = partitioner.getPartition(intWritable, longWritable, numOutputs);
      if (skippedPartitions != null && skippedPartitions.contains(partition)) {
        continue;
      }
      partitionsWithData.set(partition);
      expectedValues.get(partition).put(intWritable.get(), longWritable.get());
      kvWriter.write(intWritable, longWritable);
      numRecordsWritten++;
    }
    List<Event> events = kvWriter.close();

    if (numPartitions == 1) {
      assertEquals(true, kvWriter.skipBuffers);
    }

    int recordsPerBuffer = sizePerBuffer / sizePerRecordWithOverhead;
    int numExpectedSpills = numRecordsWritten / recordsPerBuffer / kvWriter.spillLimit;

    verify(outputContext, never()).reportFailure(any(TaskFailureType.class), any(Throwable.class), any(String.class));

    assertNull(kvWriter.currentBuffer);
    assertEquals(0, kvWriter.availableBuffers.size());

    // Verify the counters
    TezCounter outputRecordBytesCounter = counters.findCounter(TaskCounter.OUTPUT_BYTES);
    TezCounter outputRecordsCounter = counters.findCounter(TaskCounter.OUTPUT_RECORDS);
    TezCounter outputBytesWithOverheadCounter = counters
        .findCounter(TaskCounter.OUTPUT_BYTES_WITH_OVERHEAD);
    TezCounter fileOutputBytesCounter = counters.findCounter(TaskCounter.OUTPUT_BYTES_PHYSICAL);
    TezCounter spilledRecordsCounter = counters.findCounter(TaskCounter.SPILLED_RECORDS);
    TezCounter additionalSpillBytesWritternCounter = counters
        .findCounter(TaskCounter.ADDITIONAL_SPILLS_BYTES_WRITTEN);
    TezCounter additionalSpillBytesReadCounter = counters
        .findCounter(TaskCounter.ADDITIONAL_SPILLS_BYTES_READ);
    TezCounter numAdditionalSpillsCounter = counters
        .findCounter(TaskCounter.ADDITIONAL_SPILL_COUNT);
    assertEquals(numRecordsWritten * sizePerRecord, outputRecordBytesCounter.getValue());
    if (numPartitions > 1) {
      assertEquals(numRecordsWritten * sizePerRecordWithOverhead, outputBytesWithOverheadCounter.getValue());
    }
    assertEquals(numRecordsWritten, outputRecordsCounter.getValue());

    long fileOutputBytes = fileOutputBytesCounter.getValue();
    if (numRecordsWritten > 0) {
      assertTrue(fileOutputBytes > 0);
      if ((!shouldCompress) && (!dataViaEventEnabled)) {
        assertTrue(fileOutputBytes > outputRecordBytesCounter.getValue());
      }
    } else {
      assertEquals(0, fileOutputBytes);
    }
    if (!dataViaEventEnabled) {
      assertEquals(recordsPerBuffer * numExpectedSpills,
          spilledRecordsCounter.getValue());
    }
    long additionalSpillBytesWritten = additionalSpillBytesWritternCounter.getValue();
    long additionalSpillBytesRead = additionalSpillBytesReadCounter.getValue();
    if (numExpectedSpills == 0) {
      assertEquals(0, additionalSpillBytesWritten);
      assertEquals(0, additionalSpillBytesRead);
    } else {
      assertTrue(additionalSpillBytesWritten > 0);
      if (!dataViaEventEnabled) {
        assertTrue(additionalSpillBytesRead > 0);
        if (!shouldCompress) {
          assertTrue(additionalSpillBytesWritten >
              (recordsPerBuffer * numExpectedSpills * sizePerRecord));
          assertTrue(additionalSpillBytesRead >
              (recordsPerBuffer * numExpectedSpills * sizePerRecord));
        }
      } else {
        if (kvWriter.writer.getCompressedLength() >
            TezRuntimeConfiguration.TEZ_RUNTIME_TRANSFER_DATA_VIA_EVENTS_MAX_SIZE_DEFAULT) {
          assertTrue(additionalSpillBytesWritten > 0);
        }
      }
    }
    if (!dataViaEventEnabled) {
      assertEquals(additionalSpillBytesWritten, additionalSpillBytesRead);
    }
    // due to multiple threads, buffers could be merged in chunks in scheduleSpill.
    assertTrue(numExpectedSpills >= numAdditionalSpillsCounter.getValue());

    BitSet emptyPartitionBits = null;
    // Verify the events returned
    assertEquals(2, events.size());
    assertTrue(events.get(0) instanceof VertexManagerEvent);
    VertexManagerEvent vme = (VertexManagerEvent) events.get(0);
    verifyPartitionStats(vme, partitionsWithData);
    assertTrue(events.get(1) instanceof CompositeDataMovementEvent);
    CompositeDataMovementEvent cdme = (CompositeDataMovementEvent) events.get(1);
    assertEquals(0, cdme.getSourceIndexStart());
    assertEquals(numOutputs, cdme.getCount());
    DataMovementEventPayloadProto eventProto =
        DataMovementEventPayloadProto.parseFrom(ByteString.copyFrom(
            cdme.getUserPayload()));
    if (skippedPartitions == null && numRecordsWritten > 0) {
      assertFalse(eventProto.hasEmptyPartitions());
      emptyPartitionBits = new BitSet(numPartitions);
    } else {
      assertTrue(eventProto.hasEmptyPartitions());
      byte[] emptyPartitions = TezCommonUtils.decompressByteStringToByteArray(eventProto
          .getEmptyPartitions());
      emptyPartitionBits = TezUtilsInternal.fromByteArray(emptyPartitions);
      if (numRecordsWritten == 0) {
        assertEquals(numPartitions, emptyPartitionBits.cardinality());
      } else {
        for (Integer e : skippedPartitions) {
          assertTrue(emptyPartitionBits.get(e));
        }
        assertEquals(skippedPartitions.size(), emptyPartitionBits.cardinality());
      }
    }
    if (emptyPartitionBits.cardinality() != numPartitions) {
      assertEquals(HOST_STRING, eventProto.getHost());
      assertEquals(SHUFFLE_PORT, eventProto.getPort());
      assertEquals(uniqueId, eventProto.getPathComponent());
    } else {
      assertFalse(eventProto.hasHost());
      assertFalse(eventProto.hasPort());
      assertFalse(eventProto.hasPathComponent());
    }

    // Verify the actual data
    TezTaskOutput taskOutput = new TezTaskOutputFiles(conf, uniqueId, dagId);
    Path outputFilePath = kvWriter.finalOutPath;
    Path spillFilePath = kvWriter.finalIndexPath;

    if (numRecordsWritten <= 0) {
      return;
    }

    boolean isInMem= eventProto.getData().hasData();
    assertTrue(localFs.exists(outputFilePath));
    assertEquals("Incorrect output permissions (user)", FsAction.READ_WRITE,
            localFs.getFileStatus(outputFilePath).getPermission().getUserAction());
    assertEquals("Incorrect output permissions (group)", FsAction.READ,
            localFs.getFileStatus(outputFilePath).getPermission().getGroupAction());
    if( !isInMem ) {
      assertTrue(localFs.exists(spillFilePath));
      assertEquals("Incorrect index permissions (user)", FsAction.READ_WRITE,
              localFs.getFileStatus(spillFilePath).getPermission().getUserAction());
      assertEquals("Incorrect index permissions (group)", FsAction.READ,
              localFs.getFileStatus(spillFilePath).getPermission().getGroupAction());

      // verify no intermediate spill files have been left around
      synchronized (kvWriter.spillInfoList) {
        for (SpillInfo spill : kvWriter.spillInfoList) {
          assertFalse("lingering intermediate spill file " + spill.outPath,
                  localFs.exists(spill.outPath));
        }
      }
    }

    // Special case for 0 records.
    DataInputBuffer keyBuffer = new DataInputBuffer();
    DataInputBuffer valBuffer = new DataInputBuffer();
    IntWritable keyDeser = new IntWritable();
    LongWritable valDeser = new LongWritable();
    for (int i = 0; i < numOutputs; i++) {
      IFile.Reader reader = null;
      InputStream inStream;
      if (isInMem) {
        // Read from in memory payload
        int dataLoadSize = eventProto.getData().getData().size();
        inStream = new ByteArrayInputStream(eventProto.getData().getData().toByteArray());
        reader = new IFile.Reader(inStream, dataLoadSize, codec, null,
                null, false, 0, -1);
      } else {
        TezSpillRecord spillRecord = new TezSpillRecord(spillFilePath, conf);
        TezIndexRecord indexRecord = spillRecord.getIndex(i);
        if (skippedPartitions != null && skippedPartitions.contains(i)) {
          assertFalse("The Index Record for partition " + i + " should not have any data", indexRecord.hasData());
          continue;
        }

        FSDataInputStream tmpStream = FileSystem.getLocal(conf).open(outputFilePath);
        tmpStream.seek(indexRecord.getStartOffset());
        inStream = tmpStream;
        reader = new IFile.Reader(tmpStream, indexRecord.getPartLength(), codec, null,
                null, false, 0, -1);
      }

      while (reader.nextRawKey(keyBuffer)) {
        reader.nextRawValue(valBuffer);
        keyDeser.readFields(keyBuffer);
        valDeser.readFields(valBuffer);
        int partition = partitioner.getPartition(keyDeser, valDeser, numOutputs);
        assertTrue(expectedValues.get(partition).remove(keyDeser.get(), valDeser.get()));
      }
      inStream.close();
    }
    for (int i = 0; i < numOutputs; i++) {
      assertEquals(0, expectedValues.get(i).size());
      expectedValues.remove(i);
    }
    assertEquals(0, expectedValues.size());
    verify(outputContext, atLeast(1)).notifyProgress();
  }

  private static String createRandomString(int size) {
    StringBuilder sb = new StringBuilder(size);
    Random random = new Random();
    for (int i = 0; i < size; i++) {
      int r = Math.abs(random.nextInt()) % 26;
      sb.append((char) (65 + r));
    }
    return sb.toString();
  }

  private OutputContext createMockOutputContext(TezCounters counters, ApplicationId appId,
      String uniqueId, String auxiliaryService) {
    OutputContext outputContext = mock(OutputContext.class);
    doReturn(counters).when(outputContext).getCounters();
    doReturn(appId).when(outputContext).getApplicationId();
    doReturn(1).when(outputContext).getDAGAttemptNumber();
    doReturn("dagName").when(outputContext).getDAGName();
    doReturn("destinationVertexName").when(outputContext).getDestinationVertexName();
    doReturn(1).when(outputContext).getOutputIndex();
    doReturn(1).when(outputContext).getTaskAttemptNumber();
    doReturn(1).when(outputContext).getTaskIndex();
    doReturn(1).when(outputContext).getTaskVertexIndex();
    doReturn("vertexName").when(outputContext).getTaskVertexName();
    doReturn(uniqueId).when(outputContext).getUniqueIdentifier();

    doAnswer(new Answer<ByteBuffer>() {
      @Override
      public ByteBuffer answer(InvocationOnMock invocation) throws Throwable {
        ByteBuffer portBuffer = ByteBuffer.allocate(4);
        portBuffer.mark();
        portBuffer.putInt(SHUFFLE_PORT);
        portBuffer.reset();
        return portBuffer;
      }
    }).when(outputContext).getServiceProviderMetaData(eq(auxiliaryService));

    Path outDirBase = new Path(TEST_ROOT_DIR, "outDir_" + uniqueId);
    String[] outDirs = new String[] { outDirBase.toString() };
    doReturn(outDirs).when(outputContext).getWorkDirs();
    return outputContext;
  }

  private Configuration createConfiguration(OutputContext outputContext,
      Class<? extends Writable> keyClass, Class<? extends Writable> valClass,
      boolean shouldCompress, int maxSingleBufferSizeBytes) {
    return createConfiguration(outputContext, keyClass, valClass, shouldCompress,
        maxSingleBufferSizeBytes, PartitionerForTest.class);
  }

  private Configuration createConfiguration(OutputContext outputContext,
      Class<? extends Writable> keyClass, Class<? extends Writable> valClass,
      boolean shouldCompress, int maxSingleBufferSizeBytes,
      Class<? extends Partitioner> partitionerClass) {
    Configuration conf = new Configuration(false);
    conf.set(CommonConfigurationKeys.FS_PERMISSIONS_UMASK_KEY, "077");
    conf.setStrings(TezRuntimeFrameworkConfigs.LOCAL_DIRS, outputContext.getWorkDirs());
    conf.set(TezRuntimeConfiguration.TEZ_RUNTIME_KEY_CLASS, keyClass.getName());
    conf.set(TezRuntimeConfiguration.TEZ_RUNTIME_VALUE_CLASS, valClass.getName());
    conf.set(TezRuntimeConfiguration.TEZ_RUNTIME_PARTITIONER_CLASS, partitionerClass.getName());
    if (maxSingleBufferSizeBytes >= 0) {
      conf.setInt(TezRuntimeConfiguration.TEZ_RUNTIME_UNORDERED_OUTPUT_MAX_PER_BUFFER_SIZE_BYTES,
          maxSingleBufferSizeBytes);
    }
    conf.setBoolean(TezRuntimeConfiguration.TEZ_RUNTIME_COMPRESS, shouldCompress);
    if (shouldCompress) {
      conf.set(TezRuntimeConfiguration.TEZ_RUNTIME_COMPRESS_CODEC,
          DefaultCodec.class.getName());
    }
    conf.set(TezRuntimeConfiguration.TEZ_RUNTIME_REPORT_PARTITION_STATS,
        reportPartitionStats.getType());
    return conf;
  }

  public static class PartitionerForTest implements Partitioner {
    @Override
    public int getPartition(Object key, Object value, int numPartitions) {
      if (key instanceof IntWritable) {
        return ((IntWritable) key).get() % numPartitions;
      } else {
        throw new UnsupportedOperationException(
            "Test partitioner expected to be called with IntWritable only");
      }
    }
  }

  private static class UnorderedPartitionedKVWriterForTest extends UnorderedPartitionedKVWriter {

    public UnorderedPartitionedKVWriterForTest(OutputContext outputContext, Configuration conf,
        int numOutputs, long availableMemoryBytes) throws IOException {
      super(outputContext, conf, numOutputs, availableMemoryBytes);
    }

    @Override
    String getHost() {
      return HOST_STRING;
    }
  }
}
