com.datasalt.utils.mapred.joiner.TestMultiJoiner.java Source code

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Here is the source code for com.datasalt.utils.mapred.joiner.TestMultiJoiner.java

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/**
 * Copyright [2011] [Datasalt Systems S.L.]
 *
 * Licensed 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.datasalt.utils.mapred.joiner;

import static org.junit.Assert.*;

import java.io.IOException;
import java.util.Iterator;

import com.datasalt.utils.thrift.test.A;
import com.datasalt.utils.thrift.test.B;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
import org.junit.Test;

import com.datasalt.utils.commons.HadoopUtils;
import com.datasalt.utils.commons.test.BaseTest;
import com.datasalt.utils.mapred.joiner.MultiJoinChanneledMapper;
import com.datasalt.utils.mapred.joiner.MultiJoinDatum;
import com.datasalt.utils.mapred.joiner.MultiJoinPair;
import com.datasalt.utils.mapred.joiner.MultiJoinReducer;
import com.datasalt.utils.mapred.joiner.MultiJoiner;

public class TestMultiJoiner extends BaseTest {

    public static final String OUTPUT_FOR_TEST = "test-" + TestMultiJoiner.class.getName();

    /**
     * ID -> URL
     * 
     * @author pere
     *
     */
    public static class AMapper extends MultiJoinChanneledMapper<LongWritable, Text, A> {

        protected void map(LongWritable key, Text value, Context context)
                throws java.io.IOException, InterruptedException {

            A a = new A();
            String[] fields = value.toString().split("\t");
            a.setId(fields[0]);
            a.setUrl(fields[1]);
            emit(a.getUrl(), a);
        };
    }

    /**
     * URL -> URL_NORM
     * 
     * @author pere
     *
     */
    public static class BMapper extends MultiJoinChanneledMapper<LongWritable, Text, B> {

        protected void map(LongWritable key, Text value, Context context)
                throws java.io.IOException, InterruptedException {

            B b = new B();
            String[] fields = value.toString().split("\t");
            b.setUrl(fields[0]);
            b.setUrlNorm(fields[1]);
            emit(b.getUrl(), b);
        };
    }

    public static class TestReducer extends MultiJoinReducer<Text, Text> {

        @Override
        protected void reduce(@SuppressWarnings("rawtypes") MultiJoinPair arg0, Iterable<MultiJoinDatum<?>> arg1,
                Context arg2) throws java.io.IOException, InterruptedException {

            Iterator<MultiJoinDatum<?>> datums = arg1.iterator();
            /*
             * We must receive exactly two datums and the order must be A, B
             */
            MultiJoinDatum<?> datum = datums.next();
            A a = deserialize(datum);
            datum = datums.next();
            B b = deserialize(datum);
            arg2.write(new Text(a.getUrl()), new Text(b.getUrlNorm()));
        };
    }

    @Test
    public void test() throws IOException, InterruptedException, ClassNotFoundException {

        Configuration conf = getConf();
        MultiJoiner multiJoiner = new MultiJoiner("MultiJoiner Test", conf);
        multiJoiner.setReducer(TestReducer.class);
        multiJoiner.setOutputKeyClass(Text.class);
        multiJoiner.setOutputValueClass(Text.class);
        multiJoiner.setOutputFormat(TextOutputFormat.class);
        multiJoiner.setOutputPath(new Path(OUTPUT_FOR_TEST));

        Job job = multiJoiner
                .addChanneledInput(2, new Path("src/test/resources/multijoiner.test.a.txt"), A.class,
                        TextInputFormat.class, AMapper.class)
                .addChanneledInput(4, new Path("src/test/resources/multijoiner.test.b.txt"), B.class,
                        TextInputFormat.class, BMapper.class)
                .getJob();
        job.waitForCompletion(true);
        assertTrue(job.isSuccessful());

        HadoopUtils.deleteIfExists(FileSystem.get(conf), new Path(OUTPUT_FOR_TEST));
    }
}