@Override
  protected void reduce(SelectorEntry key, Iterable<WebPage> values, Context context)
      throws IOException, InterruptedException {
    for (WebPage page : values) {
      if (count >= limit) {
        return;
      }
      if (maxCount > 0) {
        String hostordomain;
        if (byDomain) {
          hostordomain = URLUtil.getDomainName(key.url);
        } else {
          hostordomain = URLUtil.getHost(key.url);
        }

        Integer hostCount = hostCountMap.get(hostordomain);
        if (hostCount == null) {
          hostCountMap.put(hostordomain, 0);
          hostCount = 0;
        }
        if (hostCount >= maxCount) {
          return;
        }
        hostCountMap.put(hostordomain, hostCount + 1);
      }

      Mark.GENERATE_MARK.putMark(page, batchId);
      page.setBatchId(batchId);
      try {
        context.write(TableUtil.reverseUrl(key.url), page);
      } catch (MalformedURLException e) {
        context.getCounter("Generator", "MALFORMED_URL").increment(1);
        continue;
      }
      context.getCounter("Generator", "GENERATE_MARK").increment(1);
      count++;
    }
  }
Ejemplo n.º 2
0
  private ParseStatus output(
      Text key,
      CrawlDatum datum,
      Content content,
      ProtocolStatus pstatus,
      int status,
      int outlinkDepth) {

    datum.setStatus(status);
    datum.setFetchTime(System.currentTimeMillis());
    if (pstatus != null) datum.getMetaData().put(Nutch.WRITABLE_PROTO_STATUS_KEY, pstatus);

    ParseResult parseResult = null;
    if (content != null) {
      Metadata metadata = content.getMetadata();

      // store the guessed content type in the crawldatum
      if (content.getContentType() != null)
        datum
            .getMetaData()
            .put(new Text(Metadata.CONTENT_TYPE), new Text(content.getContentType()));

      // add segment to metadata
      metadata.set(Nutch.SEGMENT_NAME_KEY, segmentName);
      // add score to content metadata so that ParseSegment can pick it up.
      try {
        scfilters.passScoreBeforeParsing(key, datum, content);
      } catch (Exception e) {
        if (LOG.isWarnEnabled()) {
          LOG.warn("Couldn't pass score, url " + key + " (" + e + ")");
        }
      }
      /*
       * Note: Fetcher will only follow meta-redirects coming from the
       * original URL.
       */
      if (parsing && status == CrawlDatum.STATUS_FETCH_SUCCESS) {
        if (!skipTruncated || (skipTruncated && !ParseSegment.isTruncated(content))) {
          try {
            parseResult = this.parseUtil.parse(content);
          } catch (Exception e) {
            LOG.warn("Error parsing: " + key + ": " + StringUtils.stringifyException(e));
          }
        }

        if (parseResult == null) {
          byte[] signature =
              SignatureFactory.getSignature(conf)
                  .calculate(content, new ParseStatus().getEmptyParse(conf));
          datum.setSignature(signature);
        }
      }

      /*
       * Store status code in content So we can read this value during parsing
       * (as a separate job) and decide to parse or not.
       */
      content.getMetadata().add(Nutch.FETCH_STATUS_KEY, Integer.toString(status));
    }

    try {
      output.collect(key, new NutchWritable(datum));
      if (content != null && storingContent) output.collect(key, new NutchWritable(content));
      if (parseResult != null) {
        for (Entry<Text, Parse> entry : parseResult) {
          Text url = entry.getKey();
          Parse parse = entry.getValue();
          ParseStatus parseStatus = parse.getData().getStatus();
          ParseData parseData = parse.getData();

          if (!parseStatus.isSuccess()) {
            LOG.warn("Error parsing: " + key + ": " + parseStatus);
            parse = parseStatus.getEmptyParse(conf);
          }

          // Calculate page signature. For non-parsing fetchers this will
          // be done in ParseSegment
          byte[] signature = SignatureFactory.getSignature(conf).calculate(content, parse);
          // Ensure segment name and score are in parseData metadata
          parseData.getContentMeta().set(Nutch.SEGMENT_NAME_KEY, segmentName);
          parseData.getContentMeta().set(Nutch.SIGNATURE_KEY, StringUtil.toHexString(signature));
          // Pass fetch time to content meta
          parseData.getContentMeta().set(Nutch.FETCH_TIME_KEY, Long.toString(datum.getFetchTime()));
          if (url.equals(key)) datum.setSignature(signature);
          try {
            scfilters.passScoreAfterParsing(url, content, parse);
          } catch (Exception e) {
            if (LOG.isWarnEnabled()) {
              LOG.warn("Couldn't pass score, url " + key + " (" + e + ")");
            }
          }

          String origin = null;

          // collect outlinks for subsequent db update
          Outlink[] links = parseData.getOutlinks();
          int outlinksToStore = Math.min(maxOutlinks, links.length);
          if (ignoreExternalLinks || ignoreInternalLinks) {
            URL originURL = new URL(url.toString());
            // based on domain?
            if ("bydomain".equalsIgnoreCase(ignoreExternalLinksMode)) {
              origin = URLUtil.getDomainName(originURL).toLowerCase();
            }
            // use host
            else {
              origin = originURL.getHost().toLowerCase();
            }
          }

          // used by fetchNode
          if (fetchNode != null) {
            fetchNode.setOutlinks(links);
            fetchNode.setTitle(parseData.getTitle());
            FetchNodeDb.getInstance().put(fetchNode.getUrl().toString(), fetchNode);
          }
          int validCount = 0;

          // Process all outlinks, normalize, filter and deduplicate
          List<Outlink> outlinkList = new ArrayList<Outlink>(outlinksToStore);
          HashSet<String> outlinks = new HashSet<String>(outlinksToStore);
          for (int i = 0; i < links.length && validCount < outlinksToStore; i++) {
            String toUrl = links[i].getToUrl();

            toUrl =
                ParseOutputFormat.filterNormalize(
                    url.toString(),
                    toUrl,
                    origin,
                    ignoreInternalLinks,
                    ignoreExternalLinks,
                    ignoreExternalLinksMode,
                    urlFilters,
                    urlExemptionFilters,
                    normalizers);
            if (toUrl == null) {
              continue;
            }

            validCount++;
            links[i].setUrl(toUrl);
            outlinkList.add(links[i]);
            outlinks.add(toUrl);
          }

          // Only process depth N outlinks
          if (maxOutlinkDepth > 0 && outlinkDepth < maxOutlinkDepth) {
            reporter.incrCounter("FetcherOutlinks", "outlinks_detected", outlinks.size());

            // Counter to limit num outlinks to follow per page
            int outlinkCounter = 0;

            // Calculate variable number of outlinks by depth using the
            // divisor (outlinks = Math.floor(divisor / depth * num.links))
            int maxOutlinksByDepth =
                (int)
                    Math.floor(outlinksDepthDivisor / (outlinkDepth + 1) * maxOutlinkDepthNumLinks);

            String followUrl;

            // Walk over the outlinks and add as new FetchItem to the queues
            Iterator<String> iter = outlinks.iterator();
            while (iter.hasNext() && outlinkCounter < maxOutlinkDepthNumLinks) {
              followUrl = iter.next();

              // Check whether we'll follow external outlinks
              if (outlinksIgnoreExternal) {
                if (!URLUtil.getHost(url.toString()).equals(URLUtil.getHost(followUrl))) {
                  continue;
                }
              }

              reporter.incrCounter("FetcherOutlinks", "outlinks_following", 1);

              // Create new FetchItem with depth incremented
              FetchItem fit =
                  FetchItem.create(
                      new Text(followUrl),
                      new CrawlDatum(CrawlDatum.STATUS_LINKED, interval),
                      queueMode,
                      outlinkDepth + 1);
              ((FetchItemQueues) fetchQueues).addFetchItem(fit);

              outlinkCounter++;
            }
          }

          // Overwrite the outlinks in ParseData with the normalized and
          // filtered set
          parseData.setOutlinks(outlinkList.toArray(new Outlink[outlinkList.size()]));

          output.collect(
              url,
              new NutchWritable(
                  new ParseImpl(new ParseText(parse.getText()), parseData, parse.isCanonical())));
        }
      }
    } catch (IOException e) {
      if (LOG.isErrorEnabled()) {
        LOG.error("fetcher caught:" + e.toString());
      }
    }

    // return parse status if it exits
    if (parseResult != null && !parseResult.isEmpty()) {
      Parse p = parseResult.get(content.getUrl());
      if (p != null) {
        reporter.incrCounter(
            "ParserStatus", ParseStatus.majorCodes[p.getData().getStatus().getMajorCode()], 1);
        return p.getData().getStatus();
      }
    }
    return null;
  }