org.commoncrawl.mapred.pipelineV3.domainmeta.crawlstats.DNSAndCrawlStatsJoinStep.java Source code

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Here is the source code for org.commoncrawl.mapred.pipelineV3.domainmeta.crawlstats.DNSAndCrawlStatsJoinStep.java

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/**
 * Copyright 2012 - CommonCrawl Foundation
 * 
 *    This program is free software: you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation, either version 3 of the License, or
 *    (at your option) any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 **/

package org.commoncrawl.mapred.pipelineV3.domainmeta.crawlstats;

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

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;
import org.commoncrawl.crawl.common.internal.CrawlEnvironment;
import org.commoncrawl.mapred.pipelineV3.CrawlPipelineStep;
import org.commoncrawl.mapred.pipelineV3.CrawlPipelineTask;
import org.commoncrawl.util.JobBuilder;
import org.commoncrawl.util.JoinMapper;
import org.commoncrawl.util.JoinValue;
import org.commoncrawl.util.TextBytes;

import com.google.common.collect.ImmutableList;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;

/**
 * 
 * @author rana
 *
 */
public class DNSAndCrawlStatsJoinStep extends CrawlPipelineStep
        implements Reducer<TextBytes, JoinValue, TextBytes, TextBytes> {

    enum Counters {
        GOT_CRAWL_STATS, GOT_DNS_STASTS
    }

    public static final String OUTPUT_DIR_NAME = "dnsCrawlStatsJoin";

    private static final Log LOG = LogFactory.getLog(DNSAndCrawlStatsJoinStep.class);

    JsonParser parser = new JsonParser();

    public DNSAndCrawlStatsJoinStep() {
        super(null, null, null);
    }

    public DNSAndCrawlStatsJoinStep(CrawlPipelineTask task) {
        super(task, "DNS to CrawlStats Join", OUTPUT_DIR_NAME);
    }

    @Override
    public void close() throws IOException {

    }

    @Override
    public void configure(JobConf job) {

    }

    @Override
    public Log getLogger() {
        return LOG;
    }

    @Override
    public void reduce(TextBytes key, Iterator<JoinValue> values, OutputCollector<TextBytes, TextBytes> output,
            Reporter reporter) throws IOException {
        JsonObject crawlStatsObject = null;
        JsonObject dnsStats = null;

        while (values.hasNext()) {

            JoinValue value = values.next();

            if (value.getTag().toString().equals(WWWPrefixStatsWriterStep.OUTPUT_DIR_NAME)) {
                reporter.incrCounter(Counters.GOT_CRAWL_STATS, 1);
                crawlStatsObject = parser.parse(value.getTextValue().toString()).getAsJsonObject();
            } else {
                reporter.incrCounter(Counters.GOT_DNS_STASTS, 1);
                JsonObject dnsStatsItem = parser.parse(value.getTextValue().toString()).getAsJsonObject();
                if (dnsStats == null) {
                    dnsStats = new JsonObject();
                }

                String domain = dnsStatsItem.get("domain").getAsString();
                dnsStatsItem.remove("domain");
                dnsStats.add(domain, dnsStatsItem);
            }
        }
        if (crawlStatsObject == null) {
            crawlStatsObject = new JsonObject();
        }
        if (dnsStats != null) {
            crawlStatsObject.add("dnsStats", dnsStats);
        }

        output.collect(key, new TextBytes(crawlStatsObject.toString()));
    }

    @Override
    public void runStep(Path outputPathLocation) throws IOException {
        ImmutableList<Path> inputs = new ImmutableList.Builder<Path>()
                .add(getOutputDirForStep(WWWPrefixStatsWriterStep.class))
                .add(getOutputDirForStep(DNSFailuresCollectorStep.class)).build();

        JobConf job = new JobBuilder(getDescription(), getConf())

                .inputs(inputs).inputIsSeqFile().mapper(JoinMapper.class)
                .mapperKeyValue(TextBytes.class, JoinValue.class).reducer(DNSAndCrawlStatsJoinStep.class, false)
                .outputKeyValue(TextBytes.class, TextBytes.class).reducer(DNSAndCrawlStatsJoinStep.class, false)
                .numReducers(CrawlEnvironment.NUM_DB_SHARDS / 2).outputIsSeqFile().output(outputPathLocation)

                .build();

        JobClient.runJob(job);
    }

}