/**
* 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.crawl;
import java.io.*;
import java.util.*;
// Commons Logging imports
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.io.*;
import org.apache.hadoop.fs.*;
import org.apache.hadoop.conf.*;
import org.apache.hadoop.mapred.*;
import org.apache.hadoop.util.*;
import org.apache.nutch.net.*;
import org.apache.nutch.scoring.ScoringFilterException;
import org.apache.nutch.scoring.ScoringFilters;
import org.apache.nutch.util.NutchConfiguration;
import org.apache.nutch.util.NutchJob;
/** This class takes a flat file of URLs and adds them to the of pages to be
* crawled. Useful for bootstrapping the system.
* The URL files contain one URL per line, optionally followed by custom metadata
* separated by tabs with the metadata key separated from the corresponding value by '='. <br>
* Note that some metadata keys are reserved : <br>
* - <i>nutch.score</i> : allows to set a custom score for a specific URL <br>
* - <i>nutch.fetchInterval</i> : allows to set a custom fetch interval for a specific URL <br>
* e.g. http://www.nutch.org/ \t nutch.score=10 \t nutch.fetchInterval=2592000 \t userType=open_source
**/
public class Injector extends Configured implements Tool {
public static final Log LOG = LogFactory.getLog(Injector.class);
/** metadata key reserved for setting a custom score for a specific URL */
public static String nutchScoreMDName = "nutch.score";
/** metadata key reserved for setting a custom fetchInterval for a specific URL */
public static String nutchFetchIntervalMDName = "nutch.fetchInterval";
/** Normalize and filter injected urls. */
public static class InjectMapper implements Mapper<WritableComparable, Text, Text, CrawlDatum> {
private URLNormalizers urlNormalizers;
private int interval;
private float scoreInjected;
private JobConf jobConf;
private URLFilters filters;
private ScoringFilters scfilters;
private long curTime;
public void configure(JobConf job) {
this.jobConf = job;
urlNormalizers = new URLNormalizers(job, URLNormalizers.SCOPE_INJECT);
interval = jobConf.getInt("db.fetch.interval.default", 2592000);
filters = new URLFilters(jobConf);
scfilters = new ScoringFilters(jobConf);
scoreInjected = jobConf.getFloat("db.score.injected", 1.0f);
curTime = job.getLong("injector.current.time", System.currentTimeMillis());
}
public void close() {}
public void map(WritableComparable key, Text value,
OutputCollector<Text, CrawlDatum> output, Reporter reporter)
throws IOException {
String url = value.toString(); // value is line of text
// if tabs : metadata that could be stored
// must be name=value and separated by \t
float customScore = -1f;
int customInterval = interval;
Map<String,String> metadata = new TreeMap<String,String>();
if (url.indexOf("\t")!=-1){
String[] splits = url.split("\t");
url = splits[0];
for (int s=1;s<splits.length;s++){
// find separation between name and value
int indexEquals = splits[s].indexOf("=");
if (indexEquals==-1) {
// skip anything without a =
continue;
}
String metaname = splits[s].substring(0, indexEquals);
String metavalue = splits[s].substring(indexEquals+1);
if (metaname.equals(nutchScoreMDName)) {
try {
customScore = Float.parseFloat(metavalue);}
catch (NumberFormatException nfe){}
}
else if (metaname.equals(nutchFetchIntervalMDName)) {
try {
customInterval = Integer.parseInt(metavalue);}
catch (NumberFormatException nfe){}
}
else metadata.put(metaname,metavalue);
}
}
try {
url = urlNormalizers.normalize(url, URLNormalizers.SCOPE_INJECT);
url = filters.filter(url); // filter the url
} catch (Exception e) {
if (LOG.isWarnEnabled()) { LOG.warn("Skipping " +url+":"+e); }
url = null;
}
if (url != null) { // if it passes
value.set(url); // collect it
CrawlDatum datum = new CrawlDatum(CrawlDatum.STATUS_INJECTED, customInterval);
datum.setFetchTime(curTime);
if (customScore != -1) datum.setScore(customScore);
else {
datum.setScore(scoreInjected);
try {
scfilters.injectedScore(value, datum);
} catch (ScoringFilterException e) {
if (LOG.isWarnEnabled()) {
LOG.warn("Cannot filter injected score for url " + url
+ ", using default (" + e.getMessage() + ")");
}
datum.setScore(scoreInjected);
}
}
// now add the metadata
Iterator<String> keysIter = metadata.keySet().iterator();
while (keysIter.hasNext()){
String keymd = keysIter.next();
String valuemd = metadata.get(keymd);
datum.getMetaData().put(new Text(keymd), new Text(valuemd));
}
output.collect(value, datum);
}
}
}
/** Combine multiple new entries for a url. */
public static class InjectReducer implements Reducer<Text, CrawlDatum, Text, CrawlDatum> {
public void configure(JobConf job) {}
public void close() {}
private CrawlDatum old = new CrawlDatum();
private CrawlDatum injected = new CrawlDatum();
public void reduce(Text key, Iterator<CrawlDatum> values,
OutputCollector<Text, CrawlDatum> output, Reporter reporter)
throws IOException {
boolean oldSet = false;
while (values.hasNext()) {
CrawlDatum val = values.next();
if (val.getStatus() == CrawlDatum.STATUS_INJECTED) {
injected.set(val);
injected.setStatus(CrawlDatum.STATUS_DB_UNFETCHED);
} else {
old.set(val);
oldSet = true;
}
}
CrawlDatum res = null;
if (oldSet) res = old; // don't overwrite existing value
else res = injected;
output.collect(key, res);
}
}
public Injector() {}
public Injector(Configuration conf) {
setConf(conf);
}
public void inject(Path crawlDb, Path urlDir) throws IOException {
if (LOG.isInfoEnabled()) {
LOG.info("Injector: starting");
LOG.info("Injector: crawlDb: " + crawlDb);
LOG.info("Injector: urlDir: " + urlDir);
}
Path tempDir =
new Path(getConf().get("mapred.temp.dir", ".") +
"/inject-temp-"+
Integer.toString(new Random().nextInt(Integer.MAX_VALUE)));
// map text input file to a <url,CrawlDatum> file
if (LOG.isInfoEnabled()) {
LOG.info("Injector: Converting injected urls to crawl db entries.");
}
JobConf sortJob = new NutchJob(getConf());
sortJob.setJobName("inject " + urlDir);
FileInputFormat.addInputPath(sortJob, urlDir);
sortJob.setMapperClass(InjectMapper.class);
FileOutputFormat.setOutputPath(sortJob, tempDir);
sortJob.setOutputFormat(SequenceFileOutputFormat.class);
sortJob.setOutputKeyClass(Text.class);
sortJob.setOutputValueClass(CrawlDatum.class);
sortJob.setLong("injector.current.time", System.currentTimeMillis());
JobClient.runJob(sortJob);
// merge with existing crawl db
if (LOG.isInfoEnabled()) {
LOG.info("Injector: Merging injected urls into crawl db.");
}
JobConf mergeJob = CrawlDb.createJob(getConf(), crawlDb);
FileInputFormat.addInputPath(mergeJob, tempDir);
mergeJob.setReducerClass(InjectReducer.class);
JobClient.runJob(mergeJob);
CrawlDb.install(mergeJob, crawlDb);
// clean up
FileSystem fs = FileSystem.get(getConf());
fs.delete(tempDir, true);
if (LOG.isInfoEnabled()) { LOG.info("Injector: done"); }
}
public static void main(String[] args) throws Exception {
int res = ToolRunner.run(NutchConfiguration.create(), new Injector(), args);
System.exit(res);
}
public int run(String[] args) throws Exception {
if (args.length < 2) {
System.err.println("Usage: Injector <crawldb> <url_dir>");
return -1;
}
try {
inject(new Path(args[0]), new Path(args[1]));
return 0;
} catch (Exception e) {
LOG.fatal("Injector: " + StringUtils.stringifyException(e));
return -1;
}
}
}