/** Used for redirections or when discovering sitemap URLs * */
private void handleOutlink(Tuple t, URL sURL, String newUrl, Metadata sourceMetadata) {
// build an absolute URL
try {
URL tmpURL = URLUtil.resolveURL(sURL, newUrl);
newUrl = tmpURL.toExternalForm();
} catch (MalformedURLException e) {
LOG.debug("MalformedURLException on {} or {}: {}", sURL.toExternalForm(), newUrl, e);
return;
}
// apply URL filters
if (this.urlFilters != null) {
newUrl = this.urlFilters.filter(sURL, sourceMetadata, newUrl);
}
// filtered
if (newUrl == null) {
return;
}
Metadata metadata =
metadataTransfer.getMetaForOutlink(newUrl, sURL.toExternalForm(), sourceMetadata);
// TODO check that hasn't exceeded max number of redirections
_collector.emit(
com.digitalpebble.storm.crawler.Constants.StatusStreamName,
t,
new Values(newUrl, metadata, Status.DISCOVERED));
}
private List<Outlink> toOutlinks(
String url, Metadata metadata, Map<String, List<String>> slinks) {
List<Outlink> outlinks = new LinkedList<>();
URL sourceUrl;
try {
sourceUrl = new URL(url);
} catch (MalformedURLException e) {
// we would have known by now as previous components check whether
// the URL is valid
LOG.error("MalformedURLException on {}", url);
eventCounter.scope("error_invalid_source_url").incrBy(1);
return outlinks;
}
Map<String, List<String>> linksKept = new HashMap<>();
for (Map.Entry<String, List<String>> linkEntry : slinks.entrySet()) {
String targetURL = linkEntry.getKey();
// filter the urls
if (urlFilters != null) {
targetURL = urlFilters.filter(sourceUrl, metadata, targetURL);
if (targetURL == null) {
eventCounter.scope("outlink_filtered").incr();
continue;
}
}
// the link has survived the various filters
if (targetURL != null) {
List<String> anchors = linkEntry.getValue();
linksKept.put(targetURL, anchors);
eventCounter.scope("outlink_kept").incr();
}
}
for (String outlink : linksKept.keySet()) {
// configure which metadata gets inherited from parent
Metadata linkMetadata = metadataTransfer.getMetaForOutlink(outlink, url, metadata);
Outlink ol = new Outlink(outlink);
// add the anchors to the metadata?
if (trackAnchors) {
List<String> anchors = linksKept.get(outlink);
if (anchors.size() > 0) {
linkMetadata.addValues(ANCHORS_KEY_NAME, anchors);
// sets the first anchor
ol.setAnchor(anchors.get(0));
}
}
ol.setMetadata(linkMetadata);
outlinks.add(ol);
}
return outlinks;
}