/**
* 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.mahout.classifier.df.mapreduce.partial;
import java.io.IOException;
import java.util.Arrays;
import java.util.Collection;
import java.util.Random;
import com.google.common.collect.Lists;
import com.google.common.io.Closeables;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.SequenceFile;
import org.apache.hadoop.io.SequenceFile.Writer;
import org.apache.hadoop.mapreduce.Job;
import org.apache.mahout.common.MahoutTestCase;
import org.apache.mahout.common.RandomUtils;
import org.apache.mahout.classifier.df.builder.DefaultTreeBuilder;
import org.apache.mahout.classifier.df.builder.TreeBuilder;
import org.apache.mahout.classifier.df.mapreduce.MapredOutput;
import org.apache.mahout.classifier.df.node.Leaf;
import org.apache.mahout.classifier.df.node.Node;
import org.junit.Test;
public final class PartialBuilderTest extends MahoutTestCase {
private static final int NUM_MAPS = 5;
private static final int NUM_TREES = 32;
/** instances per partition */
private static final int NUM_INSTANCES = 20;
@Test
public void testProcessOutput() throws Exception {
Configuration conf = new Configuration();
conf.setInt("mapred.map.tasks", NUM_MAPS);
Random rng = RandomUtils.getRandom();
// prepare the output
TreeID[] keys = new TreeID[NUM_TREES];
MapredOutput[] values = new MapredOutput[NUM_TREES];
int[] firstIds = new int[NUM_MAPS];
randomKeyValues(rng, keys, values, firstIds);
// store the output in a sequence file
Path base = getTestTempDirPath("testdata");
FileSystem fs = base.getFileSystem(conf);
Path outputFile = new Path(base, "PartialBuilderTest.seq");
Writer writer = SequenceFile.createWriter(fs, conf, outputFile,
TreeID.class, MapredOutput.class);
try {
for (int index = 0; index < NUM_TREES; index++) {
writer.append(keys[index], values[index]);
}
} finally {
Closeables.close(writer, false);
}
// load the output and make sure its valid
TreeID[] newKeys = new TreeID[NUM_TREES];
Node[] newTrees = new Node[NUM_TREES];
PartialBuilder.processOutput(new Job(conf), base, newKeys, newTrees);
// check the forest
for (int tree = 0; tree < NUM_TREES; tree++) {
assertEquals(values[tree].getTree(), newTrees[tree]);
}
assertTrue("keys not equal", Arrays.deepEquals(keys, newKeys));
}
/**
* Make sure that the builder passes the good parameters to the job
*
*/
@Test
public void testConfigure() {
TreeBuilder treeBuilder = new DefaultTreeBuilder();
Path dataPath = new Path("notUsedDataPath");
Path datasetPath = new Path("notUsedDatasetPath");
Long seed = 5L;
new PartialBuilderChecker(treeBuilder, dataPath, datasetPath, seed);
}
/**
* Generates random (key, value) pairs. Shuffles the partition's order
*
* @param rng
* @param keys
* @param values
* @param firstIds partitions's first ids in hadoop's order
*/
private static void randomKeyValues(Random rng, TreeID[] keys, MapredOutput[] values, int[] firstIds) {
int index = 0;
int firstId = 0;
Collection<Integer> partitions = Lists.newArrayList();
for (int p = 0; p < NUM_MAPS; p++) {
// select a random partition, not yet selected
int partition;
do {
partition = rng.nextInt(NUM_MAPS);
} while (partitions.contains(partition));
partitions.add(partition);
int nbTrees = Step1Mapper.nbTrees(NUM_MAPS, NUM_TREES, partition);
for (int treeId = 0; treeId < nbTrees; treeId++) {
Node tree = new Leaf(rng.nextInt(100));
keys[index] = new TreeID(partition, treeId);
values[index] = new MapredOutput(tree, nextIntArray(rng, NUM_INSTANCES));
index++;
}
firstIds[p] = firstId;
firstId += NUM_INSTANCES;
}
}
private static int[] nextIntArray(Random rng, int size) {
int[] array = new int[size];
for (int index = 0; index < size; index++) {
array[index] = rng.nextInt(101) - 1;
}
return array;
}
static class PartialBuilderChecker extends PartialBuilder {
private final Long seed;
private final TreeBuilder treeBuilder;
private final Path datasetPath;
PartialBuilderChecker(TreeBuilder treeBuilder, Path dataPath,
Path datasetPath, Long seed) {
super(treeBuilder, dataPath, datasetPath, seed);
this.seed = seed;
this.treeBuilder = treeBuilder;
this.datasetPath = datasetPath;
}
@Override
protected boolean runJob(Job job) throws IOException {
// no need to run the job, just check if the params are correct
Configuration conf = job.getConfiguration();
assertEquals(seed, getRandomSeed(conf));
// PartialBuilder should detect the 'local' mode and overrides the number
// of map tasks
assertEquals(1, conf.getInt("mapred.map.tasks", -1));
assertEquals(NUM_TREES, getNbTrees(conf));
assertFalse(isOutput(conf));
assertEquals(treeBuilder, getTreeBuilder(conf));
assertEquals(datasetPath, getDistributedCacheFile(conf, 0));
return true;
}
}
}