001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.snapshot;
019
020import static org.junit.Assert.assertEquals;
021
022import java.util.ArrayList;
023import java.util.List;
024import org.apache.hadoop.hbase.HBaseClassTestRule;
025import org.apache.hadoop.hbase.testclassification.RegionServerTests;
026import org.apache.hadoop.hbase.testclassification.SmallTests;
027import org.apache.hadoop.hbase.util.Pair;
028import org.junit.ClassRule;
029import org.junit.Test;
030import org.junit.experimental.categories.Category;
031
032import org.apache.hadoop.hbase.shaded.protobuf.generated.SnapshotProtos.SnapshotFileInfo;
033
034/**
035 * Test Export Snapshot Tool helpers
036 */
037@Category({ RegionServerTests.class, SmallTests.class })
038public class TestExportSnapshotHelpers {
039
040  @ClassRule
041  public static final HBaseClassTestRule CLASS_RULE =
042    HBaseClassTestRule.forClass(TestExportSnapshotHelpers.class);
043
044  /**
045   * Verfy the result of getBalanceSplits() method. The result are groups of files, used as input
046   * list for the "export" mappers. All the groups should have similar amount of data. The input
047   * list is a pair of file path and length. The getBalanceSplits() function sort it by length, and
048   * assign to each group a file, going back and forth through the groups.
049   */
050  @Test
051  public void testBalanceSplit() throws Exception {
052    // Create a list of files
053    List<Pair<SnapshotFileInfo, Long>> files = new ArrayList<>(21);
054    for (long i = 0; i <= 20; i++) {
055      SnapshotFileInfo fileInfo = SnapshotFileInfo.newBuilder().setType(SnapshotFileInfo.Type.HFILE)
056        .setHfile("file-" + i).build();
057      files.add(new Pair<>(fileInfo, i));
058    }
059
060    // Create 5 groups (total size 210)
061    // group 0: 20, 11, 10, 1 (total size: 42)
062    // group 1: 19, 12, 9, 2 (total size: 42)
063    // group 2: 18, 13, 8, 3 (total size: 42)
064    // group 3: 17, 12, 7, 4 (total size: 42)
065    // group 4: 16, 11, 6, 5 (total size: 42)
066    List<List<Pair<SnapshotFileInfo, Long>>> splits = ExportSnapshot.getBalancedSplits(files, 5);
067    assertEquals(5, splits.size());
068
069    String[] split0 = new String[] { "file-20", "file-11", "file-10", "file-1", "file-0" };
070    verifyBalanceSplit(splits.get(0), split0, 42);
071    String[] split1 = new String[] { "file-19", "file-12", "file-9", "file-2" };
072    verifyBalanceSplit(splits.get(1), split1, 42);
073    String[] split2 = new String[] { "file-18", "file-13", "file-8", "file-3" };
074    verifyBalanceSplit(splits.get(2), split2, 42);
075    String[] split3 = new String[] { "file-17", "file-14", "file-7", "file-4" };
076    verifyBalanceSplit(splits.get(3), split3, 42);
077    String[] split4 = new String[] { "file-16", "file-15", "file-6", "file-5" };
078    verifyBalanceSplit(splits.get(4), split4, 42);
079  }
080
081  private void verifyBalanceSplit(final List<Pair<SnapshotFileInfo, Long>> split,
082    final String[] expected, final long expectedSize) {
083    assertEquals(expected.length, split.size());
084    long totalSize = 0;
085    for (int i = 0; i < expected.length; ++i) {
086      Pair<SnapshotFileInfo, Long> fileInfo = split.get(i);
087      assertEquals(expected[i], fileInfo.getFirst().getHfile());
088      totalSize += fileInfo.getSecond();
089    }
090    assertEquals(expectedSize, totalSize);
091  }
092}