IndexingFiltersChecker.java

/**
 * 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.nutch.indexer;

import java.util.Arrays;
import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.apache.nutch.crawl.CrawlDatum;
import org.apache.nutch.crawl.Inlinks;
import org.apache.nutch.indexer.IndexingException;
import org.apache.nutch.indexer.IndexingFilters;
import org.apache.nutch.indexer.NutchDocument;
import org.apache.nutch.metadata.Metadata;
import org.apache.nutch.parse.Parse;
import org.apache.nutch.parse.ParseResult;
import org.apache.nutch.parse.ParseUtil;
import org.apache.nutch.protocol.Content;
import org.apache.nutch.protocol.Protocol;
import org.apache.nutch.protocol.ProtocolFactory;
import org.apache.nutch.util.NutchConfiguration;
import org.apache.nutch.util.URLUtil;

/**
 * Reads and parses a URL and run the indexers on it. Displays the fields obtained and the first
 * 100 characters of their value
 *
 * Tested with e.g. ./nutch org.apache.nutch.indexer.IndexingFiltersChecker http://www.lemonde.fr
 * @author Julien Nioche
 **/

public class IndexingFiltersChecker extends Configured implements Tool {

  public static final Logger LOG = LoggerFactory.getLogger(IndexingFiltersChecker.class);

  public IndexingFiltersChecker() {

  }

  public int run(String[] args) throws Exception {
    String contentType = null;
    String url = null;

    String usage = "Usage: IndexingFiltersChecker <url>";

    if (args.length != 1) {
      System.err.println(usage);
      System.exit(-1);
    }

    url = URLUtil.toASCII(args[0]);

    if (LOG.isInfoEnabled()) {
      LOG.info("fetching: " + url);
    }

    IndexingFilters indexers = new IndexingFilters(conf);

    ProtocolFactory factory = new ProtocolFactory(conf);
    Protocol protocol = factory.getProtocol(url);
    CrawlDatum datum = new CrawlDatum();

    Content content = protocol.getProtocolOutput(new Text(url), datum)
        .getContent();

    if (content == null) {
      System.out.println("No content for " + url);
      return 0;
    }

    contentType = content.getContentType();

    if (contentType == null) {
      return -1;
    }

    // store the guessed content type in the crawldatum
    datum.getMetaData().put(new Text(Metadata.CONTENT_TYPE), new Text(contentType));

    if (LOG.isInfoEnabled()) {
      LOG.info("parsing: " + url);
      LOG.info("contentType: " + contentType);
    }

    ParseResult parseResult = new ParseUtil(conf).parse(content);

    NutchDocument doc = new NutchDocument();
    Text urlText = new Text(url);

    Inlinks inlinks = null;
    Parse parse = parseResult.get(urlText);
    try {
      doc = indexers.filter(doc, parse, urlText, datum, inlinks);
    } catch (IndexingException e) {
      e.printStackTrace();
    }

    if (doc == null) {
      System.out.println("Document discarded by indexing filter");
      return 0;
    }
    
    for (String fname : doc.getFieldNames()) {
      List<Object> values = doc.getField(fname).getValues();
      if (values != null) {
        for (Object value : values) {
          String str = value.toString();
          int minText = Math.min(100, str.length());
          System.out.println(fname + " :\t" + str.substring(0, minText));
        }
      }
    }
    return 0;
  }

  public static void main(String[] args) throws Exception {
    final int res = ToolRunner.run(NutchConfiguration.create(),
        new IndexingFiltersChecker(), args);
    System.exit(res);
  }

  Configuration conf;

  public Configuration getConf() {
    return conf;
  }

  @Override
  public void setConf(Configuration arg0) {
    conf = arg0;
  }
}