SubcollectionIndexingFilter.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.subcollection;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.io.Text;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.apache.nutch.parse.Parse;
import org.apache.nutch.util.NutchConfiguration;

import org.apache.nutch.indexer.IndexingFilter;
import org.apache.nutch.indexer.IndexingException;
import org.apache.nutch.indexer.NutchDocument;
import org.apache.nutch.indexer.lucene.LuceneWriter;

import org.apache.nutch.collection.CollectionManager;
import org.apache.nutch.crawl.CrawlDatum;
import org.apache.nutch.crawl.Inlinks;


public class SubcollectionIndexingFilter extends Configured implements IndexingFilter {

  public SubcollectionIndexingFilter(){
    super(NutchConfiguration.create());
  }
  
  public SubcollectionIndexingFilter(Configuration conf) {
    super(conf);
  }

  /**
   * Doc field name
   */
  public static final String FIELD_NAME = "subcollection";

  /**
   * Logger
   */
  public static final Log LOG = LogFactory.getLog(SubcollectionIndexingFilter.class);

  /**
   * "Mark" document to be a part of subcollection
   * 
   * @param doc
   * @param url
   */
  private void addSubCollectionField(NutchDocument doc, String url) {
    String collname = CollectionManager.getCollectionManager(getConf()).getSubCollections(url);
    doc.add(FIELD_NAME, collname);
  }

  public NutchDocument filter(NutchDocument doc, Parse parse, Text url, CrawlDatum datum, Inlinks inlinks) throws IndexingException {
    String sUrl = url.toString();
    addSubCollectionField(doc, sUrl);
    return doc;
  }

  public void addIndexBackendOptions(Configuration conf) {
    LuceneWriter.addFieldOptions(FIELD_NAME, LuceneWriter.STORE.YES,
        LuceneWriter.INDEX.UNTOKENIZED, conf);
  }
}