/*
* Sifarish: Recommendation Engine
* Author: Pranab Ghosh
*
* 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 org.sifarish.feature;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.chombo.util.SecondarySort;
import org.chombo.util.Tuple;
import org.chombo.util.Utility;
/**
* Top match map reduce based on distance with neighbors
* @author pranab
*
*/
public class TopMatches extends Configured implements Tool {
@Override
public int run(String[] args) throws Exception {
Job job = new Job(getConf());
String jobName = "Top n matches MR";
job.setJobName(jobName);
job.setJarByClass(TopMatches.class);
FileInputFormat.addInputPath(job, new Path(args[0]));
FileOutputFormat.setOutputPath(job, new Path(args[1]));
job.setMapperClass(TopMatches.TopMatchesMapper.class);
job.setReducerClass(TopMatches.TopMatchesReducer.class);
job.setCombinerClass(TopMatches.TopMatchesCombiner.class);
job.setMapOutputKeyClass(Tuple.class);
job.setMapOutputValueClass(Text.class);
job.setOutputKeyClass(NullWritable.class);
job.setOutputValueClass(Text.class);
job.setGroupingComparatorClass(SecondarySort.TuplePairGroupComprator.class);
job.setPartitionerClass(SecondarySort.TupleTextPartitioner.class);
Utility.setConfiguration(job.getConfiguration());
int numReducer = job.getConfiguration().getInt("tom.num.reducer", -1);
numReducer = -1 == numReducer ? job.getConfiguration().getInt("num.reducer", 1) : numReducer;
job.setNumReduceTasks(numReducer);
int status = job.waitForCompletion(true) ? 0 : 1;
return status;
}
/**
* @author pranab
*
*/
public static class TopMatchesMapper extends Mapper<LongWritable, Text, Tuple, Text> {
private String srcEntityId;
private String trgEntityId;
private int rank;
private Tuple outKey = new Tuple();
private Text outVal = new Text();
private String fieldDelimRegex;
private String fieldDelim;
private int distOrdinal;
private boolean recordInOutput;
private int recLength = -1;
private String srcRec;
private String trgRec;
private int srcRecBeg;
private int srcRecEnd;
private int trgRecBeg;
private int trgRecEnd;
/* (non-Javadoc)
* @see org.apache.hadoop.mapreduce.Mapper#setup(org.apache.hadoop.mapreduce.Mapper.Context)
*/
protected void setup(Context context) throws IOException, InterruptedException {
Configuration conf = context.getConfiguration();
fieldDelim = conf.get("field.delim", ",");
fieldDelimRegex = conf.get("field.delim.regex", ",");
distOrdinal = conf.getInt("tom.distance.ordinal", -1);
recordInOutput = conf.getBoolean("tom.record.in.output", false);
}
/* (non-Javadoc)
* @see org.apache.hadoop.mapreduce.Mapper#map(KEYIN, VALUEIN, org.apache.hadoop.mapreduce.Mapper.Context)
*/
@Override
protected void map(LongWritable key, Text value, Context context)
throws IOException, InterruptedException {
String[] items = value.toString().split(fieldDelimRegex);
srcEntityId = items[0];
trgEntityId = items[1];
rank = Integer.parseInt(items[items.length - 1]);
outKey.initialize();
if (recordInOutput) {
//include source and taraget record
if (recLength == -1) {
recLength = (items.length - 3) / 2;
srcRecBeg = 2;
srcRecEnd = trgRecBeg = 2 + recLength;
trgRecEnd = trgRecBeg + recLength;
}
srcRec = org.chombo.util.Utility.join(items, srcRecBeg, srcRecEnd, fieldDelim);
trgRec = org.chombo.util.Utility.join(items, trgRecBeg, trgRecEnd, fieldDelim);
outKey.add(srcEntityId, srcRec, rank);
outVal.set(trgEntityId + fieldDelim + trgRec + fieldDelim + items[items.length - 1]);
} else {
//only target entity id and distance
outKey.add(srcEntityId, rank);
outVal.set(trgEntityId + fieldDelim + items[items.length - 1]);
}
context.write(outKey, outVal);
}
}
/**
* @author pranab
*
*/
public static class TopMatchesCombiner extends Reducer<Tuple, Text, Tuple, Text> {
private boolean nearestByCount;
private int topMatchCount;
private int topMatchDistance;
private int count;
private int distance;
private String fieldDelim;
/* (non-Javadoc)
* @see org.apache.hadoop.mapreduce.Reducer#setup(org.apache.hadoop.mapreduce.Reducer.Context)
*/
protected void setup(Context context) throws IOException, InterruptedException {
Configuration conf = context.getConfiguration();
fieldDelim = conf.get("field.delim", ",");
nearestByCount = conf.getBoolean("tom.nearest.by.count", true);
if (nearestByCount) {
topMatchCount = conf.getInt("tom.match.count", 10);
} else {
topMatchDistance = conf.getInt("tom.match.distance", 200);
}
}
/* (non-Javadoc)
* @see org.apache.hadoop.mapreduce.Reducer#reduce(KEYIN, java.lang.Iterable, org.apache.hadoop.mapreduce.Reducer.Context)
*/
protected void reduce(Tuple key, Iterable<Text> values, Context context)
throws IOException, InterruptedException {
count = 0;
for (Text value : values){
//count based neighbor
if (nearestByCount) {
context.write(key, value);
if (++count == topMatchCount){
break;
}
} else {
//distance based neighbor
distance =Integer.parseInt( value.toString().split(fieldDelim)[1]);
if (distance <= topMatchDistance ) {
context.write(key, value);
} else {
break;
}
}
}
}
}
/**
* @author pranab
*
*/
public static class TopMatchesReducer extends Reducer<Tuple, Text, NullWritable, Text> {
private boolean nearestByCount;
private boolean nearestByDistance;
private int topMatchCount;
private int topMatchDistance;
private String srcEntityId;
private int count;
private int distance;
private Text outVal = new Text();
private String fieldDelim;
private boolean recordInOutput;
private boolean compactOutput;
private List<String> valueList = new ArrayList<String>();
private boolean outputWithNoNeighbor;
/* (non-Javadoc)
* @see org.apache.hadoop.mapreduce.Reducer#setup(org.apache.hadoop.mapreduce.Reducer.Context)
*/
protected void setup(Context context) throws IOException, InterruptedException {
Configuration conf = context.getConfiguration();
fieldDelim = conf.get("field.delim", ",");
nearestByCount = conf.getBoolean("tom.nearest.by.count", true);
nearestByDistance = conf.getBoolean("tom.nearest.by.distance", false);
if (nearestByCount) {
topMatchCount = conf.getInt("tom.top.match.count", 10);
} else {
topMatchDistance = conf.getInt("tom.top.match.distance", 200);
}
recordInOutput = conf.getBoolean("tom.record.in.output", false);
compactOutput = conf.getBoolean("tom.compact.output", false);
outputWithNoNeighbor = conf.getBoolean("tom.output.with.no.neighbor", false);
}
/* (non-Javadoc)
* @see org.apache.hadoop.mapreduce.Reducer#reduce(KEYIN, java.lang.Iterable, org.apache.hadoop.mapreduce.Reducer.Context)
*/
protected void reduce(Tuple key, Iterable<Text> values, Context context)
throws IOException, InterruptedException {
srcEntityId = key.getString(0);
count = 0;
boolean doEmitNeighbor = false;
valueList.clear();
for (Text value : values){
doEmitNeighbor = false;
//count based neighbor
if (nearestByCount) {
doEmitNeighbor = true;
if (++count >= topMatchCount){
doEmitNeighbor = false;
}
}
//distance based neighbors
if (nearestByDistance) {
//distance based neighbor
String[] items = value.toString().split(fieldDelim);
distance = Integer.parseInt(items[items.length - 1]);
if (distance <= topMatchDistance ) {
if (!nearestByCount) {
doEmitNeighbor = true;
}
} else {
doEmitNeighbor = false;
}
}
if (doEmitNeighbor) {
//along with neighbors
if (compactOutput) {
if (recordInOutput) {
//contains id,record,rank - strip out entity ID and rank
String[] valueItems = value.toString().split(fieldDelim);
valueList.add(org.chombo.util.Utility.join(valueItems, 1, valueItems.length -1));
} else {
//contains id, rank
valueList.add(value.toString());
}
} else {
outVal.set(srcEntityId + fieldDelim + value.toString());
context.write(NullWritable.get(), outVal);
}
} else {
//only source entity if neighborhood condition not met
if (outputWithNoNeighbor && !compactOutput) {
outVal.set(srcEntityId);
context.write(NullWritable.get(), outVal);
}
}
}
//emit in compact format
if (compactOutput) {
boolean doEmit = true;
String srcRec = recordInOutput ? key.getString(1) : "";
int numNeighbor = valueList.size();
if ( 0 == numNeighbor) {
//only source entity if neighborhood condition not met
if (outputWithNoNeighbor) {
outVal.set(recordInOutput ? srcEntityId + fieldDelim + srcRec + fieldDelim + numNeighbor:
srcEntityId);
} else {
doEmit = false;
}
} else {
String targetValues = org.chombo.util.Utility.join(valueList, fieldDelim);
outVal.set(recordInOutput ? srcEntityId + fieldDelim + srcRec + fieldDelim + numNeighbor + targetValues :
srcEntityId + fieldDelim + targetValues);
}
if (doEmit) {
context.write(NullWritable.get(), outVal);
}
}
}
}
/**
* @param args
* @throws Exception
*/
public static void main(String[] args) throws Exception {
int exitCode = ToolRunner.run(new TopMatches(), args);
System.exit(exitCode);
}
}