/*
* Cloud9: A Hadoop toolkit for working with big data
*
* 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 edu.umd.cloud9.collection.trec;
import java.io.IOException;
import java.net.URI;
import java.util.Arrays;
import java.util.Random;
import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.CommandLineParser;
import org.apache.commons.cli.GnuParser;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.OptionBuilder;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.ParseException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.filecache.DistributedCache;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileSystem;
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.Counters;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.LineReader;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.apache.log4j.Logger;
import edu.umd.cloud9.collection.DocnoMapping;
/**
* Tool for building a document forward index for TREC collections. Run without any arguments
* for help. The guava jar must be included using {@code -libjar} for this tool to run.
*
* @author Jimmy Lin
*/
public class TrecForwardIndexBuilder extends Configured implements Tool {
private static final Logger LOG = Logger.getLogger(TrecForwardIndexBuilder.class);
private static final Random random = new Random();
private static enum Count { DOCS };
private static final String DOCNO_MAPPING_FILE_PROPERTY = "DocnoMappingFile";
private static class MyMapper extends Mapper<LongWritable, TrecDocument, IntWritable, Text> {
private static final IntWritable docno = new IntWritable(1);
private static final Text text = new Text();
private DocnoMapping docMapping;
@Override
public void setup(Context context) {
// load the docid to docno mappings
try {
Configuration conf = context.getConfiguration();
docMapping = new TrecDocnoMapping();
// Detect if we're in standalone mode; if so, we can't us the
// DistributedCache because it does not (currently) work in
// standalone mode...
if (conf.get("mapred.job.tracker").equals("local")) {
FileSystem fs = FileSystem.get(conf);
String mappingFile = conf.get(DOCNO_MAPPING_FILE_PROPERTY);
docMapping.loadMapping(new Path(mappingFile), fs);
} else {
Path[] localFiles = DistributedCache.getLocalCacheFiles(conf);
docMapping.loadMapping(localFiles[0], FileSystem.getLocal(conf));
}
} catch (Exception e) {
e.printStackTrace();
throw new RuntimeException("Error initializing DocnoMapping!");
}
}
@Override
public void map(LongWritable key, TrecDocument doc, Context context)
throws IOException, InterruptedException {
context.getCounter(Count.DOCS).increment(1);
int len = doc.getContent().getBytes().length;
docno.set(docMapping.getDocno(doc.getDocid()));
text.set(key + "\t" + len);
context.write(docno, text);
}
}
public TrecForwardIndexBuilder() {}
public static final String COLLECTION_OPTION = "collection";
public static final String INDEX_OPTION = "index";
public static final String MAPPING_OPTION = "docnoMapping";
/**
* Runs this tool.
*/
@SuppressWarnings("static-access")
public int run(String[] args) throws Exception {
Options options = new Options();
options.addOption(OptionBuilder.withArgName("path").hasArg()
.withDescription("(required) collection path").create(COLLECTION_OPTION));
options.addOption(OptionBuilder.withArgName("path").hasArg()
.withDescription("(required) output index path").create(INDEX_OPTION));
options.addOption(OptionBuilder.withArgName("path").hasArg()
.withDescription("(required) DocnoMapping data").create(MAPPING_OPTION));
CommandLine cmdline;
CommandLineParser parser = new GnuParser();
try {
cmdline = parser.parse(options, args);
} catch (ParseException exp) {
System.err.println("Error parsing command line: " + exp.getMessage());
return -1;
}
if (!cmdline.hasOption(COLLECTION_OPTION) || !cmdline.hasOption(INDEX_OPTION) ||
!cmdline.hasOption(MAPPING_OPTION)) {
HelpFormatter formatter = new HelpFormatter();
formatter.printHelp(this.getClass().getName(), options);
ToolRunner.printGenericCommandUsage(System.out);
return -1;
}
String collectionPath = cmdline.getOptionValue(COLLECTION_OPTION);
String indexFile = cmdline.getOptionValue(INDEX_OPTION);
String mappingFile = cmdline.getOptionValue(MAPPING_OPTION);
String tmpDir = "tmp-" + TrecForwardIndexBuilder.class.getSimpleName() + "-"
+ random.nextInt(10000);
Job job = new Job(getConf(),
TrecForwardIndexBuilder.class.getSimpleName() + ":" + collectionPath);
job.setJarByClass(TrecForwardIndexBuilder.class);
FileSystem fs = FileSystem.get(getConf());
LOG.info("Tool name: " + TrecForwardIndexBuilder.class.getSimpleName());
LOG.info(" - collection path: " + collectionPath);
LOG.info(" - index file: " + indexFile);
LOG.info(" - DocnoMapping file: " + mappingFile);
LOG.info(" - temp output directory: " + tmpDir);
job.setNumReduceTasks(1);
if (job.getConfiguration().get("mapred.job.tracker").equals("local")) {
job.getConfiguration().set(DOCNO_MAPPING_FILE_PROPERTY, mappingFile);
} else {
DistributedCache.addCacheFile(new URI(mappingFile), job.getConfiguration());
}
FileInputFormat.setInputPaths(job, new Path(collectionPath));
FileOutputFormat.setOutputPath(job, new Path(tmpDir));
FileOutputFormat.setCompressOutput(job, false);
job.setInputFormatClass(TrecDocumentInputFormat.class);
job.setOutputKeyClass(IntWritable.class);
job.setOutputValueClass(Text.class);
job.setMapperClass(MyMapper.class);
// delete the output directory if it exists already
FileSystem.get(getConf()).delete(new Path(tmpDir), true);
job.waitForCompletion(true);
Counters counters = job.getCounters();
int numDocs = (int) counters.findCounter(Count.DOCS).getValue();
String inputFile = tmpDir + "/" + "part-r-00000";
LOG.info("Writing " + numDocs + " doc offseta to " + indexFile);
LineReader reader = new LineReader(fs.open(new Path(inputFile)));
FSDataOutputStream writer = fs.create(new Path(indexFile), true);
writer.writeUTF(edu.umd.cloud9.collection.trec.TrecForwardIndex.class.getCanonicalName());
writer.writeUTF(collectionPath);
writer.writeInt(numDocs);
int cnt = 0;
Text line = new Text();
while (reader.readLine(line) > 0) {
String[] arr = line.toString().split("\\t");
long offset = Long.parseLong(arr[1]);
int len = Integer.parseInt(arr[2]);
writer.writeLong(offset);
writer.writeInt(len);
cnt++;
if (cnt % 100000 == 0) {
LOG.info(cnt + " docs");
}
}
reader.close();
writer.close();
LOG.info(cnt + " docs total. Done!");
if (numDocs != cnt) {
throw new RuntimeException("Unexpected number of documents in building forward index!");
}
fs.delete(new Path(tmpDir), true);
return 0;
}
/**
* Dispatches command-line arguments to the tool via the <code>ToolRunner</code>.
*/
public static void main(String[] args) throws Exception {
LOG.info("Running " + TrecForwardIndexBuilder.class.getCanonicalName() +
" with args " + Arrays.toString(args));
ToolRunner.run(new Configuration(), new TrecForwardIndexBuilder(), args);
}
}