/**
* 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.crunch.lib;
import static org.junit.Assert.assertEquals;
import java.io.Serializable;
import org.apache.crunch.MapFn;
import org.apache.crunch.PCollection;
import org.apache.crunch.PTable;
import org.apache.crunch.Pair;
import org.apache.crunch.Pipeline;
import org.apache.crunch.PipelineResult;
import org.apache.crunch.PipelineResult.StageResult;
import org.apache.crunch.impl.mr.MRPipeline;
import org.apache.crunch.io.From;
import org.apache.crunch.io.To;
import org.apache.crunch.test.CrunchTestSupport;
import org.apache.crunch.types.avro.Avros;
import org.apache.crunch.types.writable.Writables;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.Reducer;
import org.junit.Before;
import org.junit.Test;
public class MapreduceIT extends CrunchTestSupport implements Serializable {
private static class TestMapper extends Mapper<IntWritable, Text, IntWritable, Text> {
@Override
protected void map(IntWritable k, Text v, Mapper<IntWritable, Text, IntWritable, Text>.Context ctxt) {
try {
ctxt.getCounter("written", "out").increment(1L);
ctxt.write(new IntWritable(v.getLength()), v);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
private static class TestReducer extends Reducer<IntWritable, Text, Text, LongWritable> {
protected void reduce(IntWritable key, Iterable<Text> values,
org.apache.hadoop.mapreduce.Reducer<IntWritable, Text, Text, LongWritable>.Context ctxt) {
boolean hasWhere = false;
String notWhere = "";
for (Text t : values) {
String next = t.toString();
if (next.contains("where")) {
hasWhere = true;
ctxt.getCounter("words", "where").increment(1);
} else {
notWhere = next;
}
}
try {
ctxt.write(new Text(notWhere), hasWhere ? new LongWritable(1L) : new LongWritable(0L));
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
@Test
public void testMapper() throws Exception {
Pipeline p = new MRPipeline(MapreduceIT.class, tempDir.getDefaultConfiguration());
Path shakesPath = tempDir.copyResourcePath("shakes.txt");
PCollection<String> in = p.read(From.textFile(shakesPath));
PTable<IntWritable, Text> two = in.parallelDo(new MapFn<String, Pair<IntWritable, Text>>() {
@Override
public Pair<IntWritable, Text> map(String input) {
return Pair.of(new IntWritable(input.length()), new Text(input));
}
}, Writables.tableOf(Writables.writables(IntWritable.class), Writables.writables(Text.class)));
PTable<IntWritable, Text> out = Mapreduce.map(two, TestMapper.class, IntWritable.class, Text.class);
out.write(To.sequenceFile(tempDir.getPath("temp")));
PipelineResult res = p.done();
assertEquals(1, res.getStageResults().size());
StageResult sr = res.getStageResults().get(0);
assertEquals(3667, sr.getCounters().findCounter("written", "out").getValue());
}
@Test
public void testReducer() throws Exception {
Pipeline p = new MRPipeline(MapredIT.class, tempDir.getDefaultConfiguration());
Path shakesPath = tempDir.copyResourcePath("shakes.txt");
PCollection<String> in = p.read(From.textFile(shakesPath));
PTable<IntWritable, Text> two = in.parallelDo(new MapFn<String, Pair<IntWritable, Text>>() {
@Override
public Pair<IntWritable, Text> map(String input) {
return Pair.of(new IntWritable(input.length()), new Text(input));
}
}, Writables.tableOf(Writables.writables(IntWritable.class), Writables.writables(Text.class)));
PTable<Text, LongWritable> out = Mapreduce.reduce(two.groupByKey(), TestReducer.class, Text.class, LongWritable.class);
out.write(To.sequenceFile(tempDir.getPath("temp")));
PipelineResult res = p.done();
assertEquals(1, res.getStageResults().size());
StageResult sr = res.getStageResults().get(0);
assertEquals(19, sr.getCounters().findCounter("words", "where").getValue());
}
}