// CrawlQueues.java
// (C) 2007 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
// first published 29.10.2007 on http://yacy.net
//
// This is a part of YaCy, a peer-to-peer based web search engine
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
// LICENSE
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
package net.yacy.crawler.data;
import java.io.File;
import java.io.IOException;
import java.net.MalformedURLException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;
import org.apache.solr.client.solrj.SolrQuery;
import org.apache.solr.client.solrj.response.QueryResponse;
import org.apache.solr.common.SolrDocument;
import org.apache.solr.common.SolrException;
import net.yacy.cora.document.encoding.ASCII;
import net.yacy.cora.document.encoding.UTF8;
import net.yacy.cora.document.feed.Hit;
import net.yacy.cora.document.feed.RSSFeed;
import net.yacy.cora.document.id.DigestURL;
import net.yacy.cora.federate.solr.FailCategory;
import net.yacy.cora.federate.solr.connector.SolrConnector;
import net.yacy.cora.federate.yacy.CacheStrategy;
import net.yacy.cora.order.Base64Order;
import net.yacy.cora.protocol.ConnectionInfo;
import net.yacy.cora.util.ConcurrentLog;
import net.yacy.crawler.HarvestProcess;
import net.yacy.crawler.data.NoticedURL.StackType;
import net.yacy.crawler.retrieval.Request;
import net.yacy.crawler.retrieval.Response;
import net.yacy.crawler.robots.RobotsTxtEntry;
import net.yacy.kelondro.workflow.WorkflowJob;
import net.yacy.peers.DHTSelection;
import net.yacy.peers.Protocol;
import net.yacy.peers.Seed;
import net.yacy.repository.Blacklist.BlacklistType;
import net.yacy.search.IndexingQueueEntry;
import net.yacy.search.Switchboard;
import net.yacy.search.SwitchboardConstants;
import net.yacy.search.index.ErrorCache;
public class CrawlQueues {
private final static Request POISON_REQUEST = new Request();
private final static ConcurrentLog log = new ConcurrentLog("CRAWLER");
private final Switchboard sb;
private final Loader[] worker;
private final ArrayBlockingQueue<Request> workerQueue;
private ArrayList<String> remoteCrawlProviderHashes;
public NoticedURL noticeURL;
public ErrorCache errorURL;
public Map<String, DigestURL> delegatedURL;
public CrawlQueues(final Switchboard sb, final File queuePath) {
this.sb = sb;
final int maxWorkers = (int) sb.getConfigLong(SwitchboardConstants.CRAWLER_THREADS_ACTIVE_MAX, 10);
this.worker = new Loader[maxWorkers];
this.workerQueue = new ArrayBlockingQueue<Request>(200);
this.remoteCrawlProviderHashes = null;
// start crawling management
log.config("Starting Crawling Management");
log.config("Opening noticeURL..");
this.noticeURL = new NoticedURL(queuePath, sb.getConfigInt("crawler.onDemandLimit", 1000), sb.exceed134217727);
log.config("Opening errorURL..");
this.errorURL = new ErrorCache(sb.index.fulltext());
log.config("Opening delegatedURL..");
this.delegatedURL = null;
}
public void initRemoteCrawlQueues () {
if (this.remoteCrawlProviderHashes == null) this.remoteCrawlProviderHashes = new ArrayList<String>();
if (this.delegatedURL == null) {
this.delegatedURL = new ConcurrentHashMap<String, DigestURL>();
log.config("Finishted Startup of Crawling Management");
}
}
/**
* Relocation is necessary if the user switches the network.
* Because this object is part of the scheduler we cannot simply close that object and create a new one.
* Instead, the 'living' content of this object is destroyed.
* @param newQueuePath
*/
public void relocate(final File newQueuePath) {
// removed pending requests
this.workerQueue.clear();
this.errorURL.clearCache();
if (this.remoteCrawlProviderHashes != null) this.remoteCrawlProviderHashes.clear();
this.noticeURL.close();
this.noticeURL = new NoticedURL(newQueuePath, sb.getConfigInt("crawler.onDemandLimit", 1000), this.sb.exceed134217727);
if (this.delegatedURL != null) this.delegatedURL.clear();
}
public synchronized void close() {
// removed pending requests
this.workerQueue.clear();
// wait for all workers to finish
for (int i = 0; i < this.worker.length; i++) {
try {this.workerQueue.put(POISON_REQUEST);} catch (InterruptedException e) {}
}
for (final Loader w: this.worker) {
if (w != null && w.isAlive()) {
try {
w.join(1000);
if (w.isAlive()) w.interrupt();
} catch (final InterruptedException e) {
ConcurrentLog.logException(e);
}
}
}
this.noticeURL.close();
if (this.delegatedURL != null) this.delegatedURL.clear();
}
public void clear() {
// wait for all workers to finish
this.workerQueue.clear();
for (final Loader w: this.worker) if (w != null) w.interrupt();
if (this.remoteCrawlProviderHashes != null) this.remoteCrawlProviderHashes.clear();
this.noticeURL.clear();
if (this.delegatedURL != null) this.delegatedURL.clear();
}
/**
* tests if hash occurs in any database
* @param hash
* @return if the hash exists, the name of the database is returned, otherwise null is returned
*/
public HarvestProcess exists(final byte[] hash) {
if (this.delegatedURL != null && this.delegatedURL.containsKey(ASCII.String(hash))) {
return HarvestProcess.DELEGATED;
}
//if (this.noticeURL.existsInStack(hash)) {
// return HarvestProcess.CRAWLER;
//} // this is disabled because it prevents proper crawling of smb shares. The cause is unknown
for (final Request request: activeWorkerEntries().values()) {
if (Base64Order.enhancedCoder.equal(request.url().hash(), hash)) {
return HarvestProcess.WORKER;
}
}
return null;
}
/**
* count the number of same host names in the worker
* @param host
* @return
*/
public int hostcount(final String host) {
if (host == null || host.length() == 0) return 0;
int c = 0;
for (final DigestURL url: activeWorkerEntries().keySet()) {
if (host.equals(url.getHost())) {
c++;
}
}
return c;
}
public void removeURL(final byte[] hash) {
assert hash != null && hash.length == 12;
this.noticeURL.removeByURLHash(hash);
if (this.delegatedURL != null) this.delegatedURL.remove(hash);
}
public int removeHosts(final Set<String> hosthashes) {
return this.noticeURL.removeByHostHash(hosthashes);
//this.delegatedURL.remove(hash);
}
public DigestURL getURL(final byte[] urlhash) {
assert urlhash != null;
if (urlhash == null || urlhash.length == 0) {
return null;
}
if (this.delegatedURL != null) {
DigestURL u = this.delegatedURL.get(ASCII.String(urlhash));
if (u != null) {
return u;
}
}
for (final DigestURL url: activeWorkerEntries().keySet()) {
if (Base64Order.enhancedCoder.equal(url.hash(), urlhash)) {
return url;
}
}
final Request ne = this.noticeURL.get(urlhash);
if (ne != null) {
return ne.url();
}
return null;
}
public void freemem() {
if ((this.errorURL.stackSize() > 1)) {
log.warn("freemem: Cleaning Error-URLs report stack, "
+ this.errorURL.stackSize()
+ " entries on stack");
this.errorURL.clearStack();
}
}
public Map<DigestURL, Request> activeWorkerEntries() {
synchronized (this.worker) {
Map<DigestURL, Request> map = new HashMap<DigestURL, Request>();
for (final Loader w: this.worker) {
if (w != null) {
Request r = w.loading();
if (r != null) map.put(r.url(), r);
}
}
return map;
}
}
public int coreCrawlJobSize() {
return this.noticeURL.stackSize(NoticedURL.StackType.LOCAL) + this.noticeURL.stackSize(NoticedURL.StackType.NOLOAD);
}
public boolean coreCrawlJob() {
final boolean robinsonPrivateCase = (this.sb.isRobinsonMode() &&
!this.sb.getConfig(SwitchboardConstants.CLUSTER_MODE, "").equals(SwitchboardConstants.CLUSTER_MODE_PUBLIC_CLUSTER));
if ((robinsonPrivateCase || coreCrawlJobSize() <= 20) && limitCrawlJobSize() > 0) {
// move some tasks to the core crawl job so we have something to do
final int toshift = Math.min(10, limitCrawlJobSize()); // this cannot be a big number because the balancer makes a forced waiting if it cannot balance
for (int i = 0; i < toshift; i++) {
this.noticeURL.shift(NoticedURL.StackType.GLOBAL, NoticedURL.StackType.LOCAL, this.sb.crawler, this.sb.robots);
}
CrawlQueues.log.info("shifted " + toshift + " jobs from global crawl to local crawl (coreCrawlJobSize()=" + coreCrawlJobSize() +
", limitCrawlJobSize()=" + limitCrawlJobSize() + ", cluster.mode=" + this.sb.getConfig(SwitchboardConstants.CLUSTER_MODE, "") +
", robinsonMode=" + ((this.sb.isRobinsonMode()) ? "on" : "off"));
}
final String queueCheckCore = loadIsPossible(NoticedURL.StackType.LOCAL);
final String queueCheckNoload = loadIsPossible(NoticedURL.StackType.NOLOAD);
if (queueCheckCore != null && queueCheckNoload != null) {
if (CrawlQueues.log.isFine()) {
CrawlQueues.log.fine("omitting de-queue/local: " + queueCheckCore + ":" + queueCheckNoload);
}
return false;
}
if (isPaused(SwitchboardConstants.CRAWLJOB_LOCAL_CRAWL)) {
if (CrawlQueues.log.isFine()) {
CrawlQueues.log.fine("omitting de-queue/local: paused");
}
return false;
}
// do a local crawl
Request urlEntry;
while (!this.noticeURL.isEmpty(NoticedURL.StackType.LOCAL) || !this.noticeURL.isEmpty(NoticedURL.StackType.NOLOAD)) {
final String stats = "LOCALCRAWL[" +
this.noticeURL.stackSize(NoticedURL.StackType.NOLOAD) + ", " +
this.noticeURL.stackSize(NoticedURL.StackType.LOCAL) + ", " +
this.noticeURL.stackSize(NoticedURL.StackType.GLOBAL) +
", " + this.noticeURL.stackSize(NoticedURL.StackType.REMOTE) + "]";
try {
if (!this.noticeURL.isEmpty(NoticedURL.StackType.NOLOAD)) {
// get one entry that will not be loaded, just indexed
urlEntry = this.noticeURL.pop(NoticedURL.StackType.NOLOAD, true, this.sb.crawler, this.sb.robots);
if (urlEntry == null) {
continue;
}
final String profileHandle = urlEntry.profileHandle();
if (profileHandle == null) {
CrawlQueues.log.severe(stats + ": NULL PROFILE HANDLE '" + urlEntry.profileHandle() + "' for URL " + urlEntry.url());
return true;
}
final CrawlProfile profile = this.sb.crawler.get(ASCII.getBytes(profileHandle));
if (profile == null) {
CrawlQueues.log.severe(stats + ": NULL PROFILE HANDLE '" + urlEntry.profileHandle() + "' for URL " + urlEntry.url());
return true;
}
this.sb.indexingDocumentProcessor.enQueue(new IndexingQueueEntry(new Response(urlEntry, profile), null, null));
ConcurrentLog.info("CrawlQueues", "placed NOLOAD URL on indexing queue: " + urlEntry.url().toNormalform(true));
return true;
}
urlEntry = this.noticeURL.pop(NoticedURL.StackType.LOCAL, true, this.sb.crawler, this.sb.robots);
if (urlEntry == null) {
continue;
}
// System.out.println("DEBUG plasmaSwitchboard.processCrawling:
// profileHandle = " + profileHandle + ", urlEntry.url = " + urlEntry.url());
if (urlEntry.profileHandle() == null) {
CrawlQueues.log.severe(stats + ": NULL PROFILE HANDLE '" + urlEntry.profileHandle() + "' for URL " + urlEntry.url());
return true;
}
load(urlEntry, stats);
return true;
} catch (final IOException e) {
CrawlQueues.log.severe(stats + ": CANNOT FETCH ENTRY: " + e.getMessage(), e);
if (e.getMessage() != null && e.getMessage().indexOf("hash is null",0) > 0) {
this.noticeURL.clear(NoticedURL.StackType.LOCAL);
}
}
}
return true;
}
/**
* Make some checks if crawl is valid and start it
*
* @param urlEntry
* @param profileHandle
* @param stats String for log prefixing
* @return
*/
private void load(final Request urlEntry, final String stats) {
final CrawlProfile profile = this.sb.crawler.get(UTF8.getBytes(urlEntry.profileHandle()));
if (profile != null) {
// check if the protocol is supported
final DigestURL url = urlEntry.url();
final String urlProtocol = url.getProtocol();
if (this.sb.loader.isSupportedProtocol(urlProtocol)) {
if (CrawlQueues.log.isFine()) {
CrawlQueues.log.fine(stats + ": URL=" + urlEntry.url()
+ ", initiator=" + ((urlEntry.initiator() == null) ? "" : ASCII.String(urlEntry.initiator()))
+ ", crawlOrder=" + ((profile.remoteIndexing()) ? "true" : "false")
+ ", depth=" + urlEntry.depth()
+ ", crawlDepth=" + profile.depth()
+ ", must-match=" + profile.urlMustMatchPattern().toString()
+ ", must-not-match=" + profile.urlMustNotMatchPattern().toString()
+ ", permission=" + ((this.sb.peers == null) ? "undefined" : (((this.sb.peers.mySeed().isSenior()) || (this.sb.peers.mySeed().isPrincipal())) ? "true" : "false")));
}
// work off one Crawl stack entry
if (urlEntry == null || urlEntry.url() == null) {
CrawlQueues.log.info(stats + ": urlEntry = null");
} else {
if (!activeWorkerEntries().containsKey(urlEntry.url())) {
try {
ensureLoaderRunning();
this.workerQueue.put(urlEntry);
} catch (InterruptedException e) {
ConcurrentLog.logException(e);
}
}
}
} else {
CrawlQueues.log.severe("Unsupported protocol in URL '" + url.toNormalform(false));
}
} else {
if (CrawlQueues.log.isFine()) CrawlQueues.log.fine(stats + ": LOST PROFILE HANDLE '" + urlEntry.profileHandle() + "' for URL " + urlEntry.url());
}
}
/**
* if crawling was paused we have to wait until we were notified to continue
* blocks until pause is ended
* @param crawljob
* @return
*/
private boolean isPaused(final String crawljob) {
final Object[] status = this.sb.crawlJobsStatus.get(crawljob);
boolean pauseEnded = false;
synchronized(status[SwitchboardConstants.CRAWLJOB_SYNC]) {
if (((Boolean)status[SwitchboardConstants.CRAWLJOB_STATUS]).booleanValue()) {
try {
status[SwitchboardConstants.CRAWLJOB_SYNC].wait();
}
catch (final InterruptedException e) { pauseEnded = true;}
}
}
return pauseEnded;
}
/**
* Checks if crawl queue has elements and new crawl will not exceed thread-limit
* @param stackType
* @return
*/
private String loadIsPossible(final StackType stackType) {
//System.out.println("stacksize = " + noticeURL.stackSize(stackType));
if (this.noticeURL.isEmpty(stackType)) {
//log.logDebug("GlobalCrawl: queue is empty");
return "stack is empty";
}
// check again
if (this.workerQueue.remainingCapacity() == 0) {
return "too many workers active: " + this.workerQueue.size();
}
final String cautionCause = this.sb.onlineCaution();
if (cautionCause != null) {
return "online caution: " + cautionCause;
}
return null;
}
public boolean remoteCrawlLoaderJob() {
// check if we are allowed to crawl urls provided by other peers
if (!this.sb.peers.mySeed().getFlagAcceptRemoteCrawl()) {
//this.log.logInfo("remoteCrawlLoaderJob: not done, we are not allowed to do that");
return false;
}
// check if we are a senior peer
if (!this.sb.peers.mySeed().isActive()) {
//this.log.logInfo("remoteCrawlLoaderJob: not done, this should be a senior or principal peer");
return false;
}
// check again
if (this.workerQueue.remainingCapacity() == 0) {
if (CrawlQueues.log.isFine()) {
CrawlQueues.log.fine("remoteCrawlLoaderJob: too many processes in loader queue, dismissed (" + "workerQueue=" + this.workerQueue.size() + "), httpClients = " + ConnectionInfo.getCount());
}
return false;
}
final String cautionCause = this.sb.onlineCaution();
if (cautionCause != null) {
if (CrawlQueues.log.isFine()) {
CrawlQueues.log.fine("remoteCrawlLoaderJob: online caution for " + cautionCause + ", omitting processing");
}
return false;
}
if (remoteTriggeredCrawlJobSize() > 200) {
if (CrawlQueues.log.isFine()) {
CrawlQueues.log.fine("remoteCrawlLoaderJob: the remote-triggered crawl job queue is filled, omitting processing");
}
return false;
}
if (coreCrawlJobSize() > 0 /*&& sb.indexingStorageProcessor.queueSize() > 0*/) {
if (CrawlQueues.log.isFine()) {
CrawlQueues.log.fine("remoteCrawlLoaderJob: a local crawl is running, omitting processing");
}
return false;
}
// check if we have an entry in the provider list, otherwise fill the list
Seed seed;
if (this.remoteCrawlProviderHashes != null && this.remoteCrawlProviderHashes.isEmpty()) {
if (this.sb.peers != null && this.sb.peers.sizeConnected() > 0) {
final Iterator<Seed> e = DHTSelection.getProvidesRemoteCrawlURLs(this.sb.peers);
while (e.hasNext()) {
seed = e.next();
if (seed != null) {
this.remoteCrawlProviderHashes.add(seed.hash);
}
}
}
}
if (this.remoteCrawlProviderHashes == null || this.remoteCrawlProviderHashes.isEmpty()) {
return false;
}
// take one entry from the provider list and load the entries from the remote peer
seed = null;
String hash = null;
while (seed == null && (this.remoteCrawlProviderHashes != null && !this.remoteCrawlProviderHashes.isEmpty())) {
hash = this.remoteCrawlProviderHashes.remove(this.remoteCrawlProviderHashes.size() - 1);
if (hash == null) {
continue;
}
seed = this.sb.peers.get(hash);
if (seed == null) {
continue;
}
// check if the peer is inside our cluster
if ((this.sb.isRobinsonMode()) && (!this.sb.isInMyCluster(seed))) {
seed = null;
continue;
}
}
if (seed == null) {
return false;
}
// we know a peer which should provide remote crawl entries. load them now.
final RSSFeed feed = Protocol.queryRemoteCrawlURLs(this.sb.peers, seed, 60, 10000);
if (feed == null || feed.isEmpty()) {
// try again and ask another peer
return remoteCrawlLoaderJob();
}
// parse the rss
DigestURL url, referrer;
Date loaddate;
for (final Hit item: feed) {
//System.out.println("URL=" + item.getLink() + ", desc=" + item.getDescription() + ", pubDate=" + item.getPubDate());
// put url on remote crawl stack
try {
url = new DigestURL(item.getLink());
} catch (final MalformedURLException e) {
continue;
}
try {
referrer = new DigestURL(item.getReferrer());
} catch (final MalformedURLException e) {
referrer = null;
}
loaddate = item.getPubDate();
final String urlRejectReason = this.sb.crawlStacker.urlInAcceptedDomain(url);
if (urlRejectReason == null) {
// stack url
if (this.sb.getLog().isFinest()) {
this.sb.getLog().finest("crawlOrder: stack: url='" + url + "'");
}
this.sb.crawlStacker.enqueueEntry(new Request(
ASCII.getBytes(hash),
url,
(referrer == null) ? null : referrer.hash(),
item.getDescriptions().size() > 0 ? item.getDescriptions().get(0) : "",
loaddate,
this.sb.crawler.defaultRemoteProfile.handle(),
0,
this.sb.crawler.defaultRemoteProfile.timezoneOffset()
));
} else {
CrawlQueues.log.warn("crawlOrder: Rejected URL '" + urlToString(url) + "': " + urlRejectReason);
}
}
return true;
}
public boolean autocrawlJob() {
if (!this.sb.getConfigBool(SwitchboardConstants.AUTOCRAWL, false)) {
return false;
}
if (isPaused(SwitchboardConstants.CRAWLJOB_LOCAL_CRAWL)) {
return false;
}
if (coreCrawlJobSize() > 200) {
return false;
}
String rows = this.sb.getConfig(SwitchboardConstants.AUTOCRAWL_ROWS, "100");
String dateQuery = String.format("load_date_dt:[* TO NOW-%sDAY]", this.sb.getConfig(SwitchboardConstants.AUTOCRAWL_DAYS, "1"));
final SolrQuery query = new SolrQuery();
query.add("group", "true");
query.add("group.field", "host_s");
query.add("group.limit", "1");
query.add("group.main", "true");
query.add("rows", rows);
query.setQuery(this.sb.getConfig(SwitchboardConstants.AUTOCRAWL_QUERY, "*:*"));
query.setFields("host_s,url_protocol_s");
query.addSort("load_date_dt", SolrQuery.ORDER.asc);
query.addFilterQuery(dateQuery);
try {
QueryResponse resp = sb.index.fulltext().getDefaultConnector().getResponseByParams(query);
int i = 0;
int deepRatio = Integer.parseInt(this.sb.getConfig(SwitchboardConstants.AUTOCRAWL_RATIO, "50"));
for (SolrDocument doc: resp.getResults()) {
boolean deep = false;
i++;
if( i % deepRatio == 0 ){
deep = true;
}
DigestURL url;
final String u = doc.getFieldValue("url_protocol_s").toString() + "://" + doc.getFieldValue("host_s").toString();
try {
url = new DigestURL(u);
} catch (final MalformedURLException e) {
continue;
}
final String urlRejectReason = this.sb.crawlStacker.urlInAcceptedDomain(url);
if (urlRejectReason == null) {
this.sb.crawlStacker.enqueueEntry(new Request(
ASCII.getBytes(this.sb.peers.mySeed().hash),
url,
null,
"CRAWLING-ROOT",
new Date(),
deep ? this.sb.crawler.defaultAutocrawlDeepProfile.handle() : this.sb.crawler.defaultAutocrawlShallowProfile.handle(),
0,
deep ? this.sb.crawler.defaultAutocrawlDeepProfile.timezoneOffset() : this.sb.crawler.defaultAutocrawlShallowProfile.timezoneOffset()
));
} else {
CrawlQueues.log.warn("autocrawl: Rejected URL '" + urlToString(url) + "': " + urlRejectReason);
}
}
} catch (SolrException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return true;
}
/**
* @param url
* @return
*/
private static String urlToString(final DigestURL url) {
return (url == null ? "null" : url.toNormalform(true));
}
public int limitCrawlJobSize() {
return this.noticeURL.stackSize(NoticedURL.StackType.GLOBAL);
}
public int noloadCrawlJobSize() {
return this.noticeURL.stackSize(NoticedURL.StackType.NOLOAD);
}
public int remoteTriggeredCrawlJobSize() {
return this.noticeURL.stackSize(NoticedURL.StackType.REMOTE);
}
public boolean remoteTriggeredCrawlJob() {
// work off crawl requests that had been placed by other peers to our crawl stack
// do nothing if either there are private processes to be done
// or there is no global crawl on the stack
final String queueCheck = loadIsPossible(NoticedURL.StackType.REMOTE);
if (queueCheck != null) {
if (CrawlQueues.log.isFinest()) {
CrawlQueues.log.finest("omitting de-queue/remote: " + queueCheck);
}
return false;
}
if (isPaused(SwitchboardConstants.CRAWLJOB_REMOTE_TRIGGERED_CRAWL)) {
if (CrawlQueues.log.isFinest()) {
CrawlQueues.log.finest("omitting de-queue/remote: paused");
}
return false;
}
// we don't want to crawl a global URL globally, since WE are the global part. (from this point of view)
final String stats = "REMOTETRIGGEREDCRAWL[" + this.noticeURL.stackSize(NoticedURL.StackType.LOCAL) + ", " + this.noticeURL.stackSize(NoticedURL.StackType.GLOBAL) + ", "
+ this.noticeURL.stackSize(NoticedURL.StackType.REMOTE) + "]";
try {
final Request urlEntry = this.noticeURL.pop(NoticedURL.StackType.REMOTE, true, this.sb.crawler, this.sb.robots);
if (urlEntry == null) return false;
load(urlEntry, stats);
return true;
} catch (final IOException e) {
CrawlQueues.log.severe(stats + ": CANNOT FETCH ENTRY: " + e.getMessage(), e);
if (e.getMessage().indexOf("hash is null",0) > 0) {
this.noticeURL.clear(NoticedURL.StackType.REMOTE);
}
return true;
}
}
private void ensureLoaderRunning() {
// check if there is at least one loader available
for (int i = 0; i < this.worker.length; i++) {
if (this.worker[i] == null || !this.worker[i].isAlive()) {
this.worker[i] = new Loader();
this.worker[i].start();
return;
}
if (this.worker[i].loading() == null) return;
}
}
private final class Loader extends Thread {
private Request request = null;
private Loader() {
}
public Request loading() {
return request;
}
@Override
public void run() {
this.setPriority(Thread.MIN_PRIORITY); // http requests from the crawler should not cause that other functions work worse
try {
while ((request = CrawlQueues.this.workerQueue.poll(10, TimeUnit.SECONDS)) != POISON_REQUEST) {
if (request == null) break; // we run this only for a specific time and then let the process die to clear up resources
request.setStatus("worker-initialized", WorkflowJob.STATUS_INITIATED);
this.setName("CrawlQueues.Loader(" + request.url().toNormalform(false) + ")");
CrawlProfile profile = CrawlQueues.this.sb.crawler.get(UTF8.getBytes(request.profileHandle()));
try {
// checking robots.txt for http(s) resources
request.setStatus("worker-checkingrobots", WorkflowJob.STATUS_STARTED);
RobotsTxtEntry robotsEntry;
if ((request.url().getProtocol().equals("http") || request.url().getProtocol().equals("https")) &&
(robotsEntry = CrawlQueues.this.sb.robots.getEntry(request.url(), profile.getAgent())) != null &&
robotsEntry.isDisallowed(request.url())) {
//if (log.isFine()) log.logFine("Crawling of URL '" + request.url().toString() + "' disallowed by robots.txt.");
CrawlQueues.this.errorURL.push(request.url(), request.depth(), profile, FailCategory.FINAL_ROBOTS_RULE, "denied by robots.txt", -1);
request.setStatus("worker-disallowed", WorkflowJob.STATUS_FINISHED);
} else {
// starting a load from the internet
request.setStatus("worker-loading", WorkflowJob.STATUS_RUNNING);
String error = null;
// load a resource and push queue entry to switchboard queue
// returns null if everything went fine, a fail reason string if a problem occurred
try {
request.setStatus("loading", WorkflowJob.STATUS_RUNNING);
final Response response = CrawlQueues.this.sb.loader.load(request, profile == null ? CacheStrategy.IFEXIST : profile.cacheStrategy(), BlacklistType.CRAWLER, profile.getAgent());
if (response == null) {
request.setStatus("error", WorkflowJob.STATUS_FINISHED);
if (CrawlQueues.log.isFine()) {
CrawlQueues.log.fine("problem loading " + request.url().toString() + ": no content (possibly caused by cache policy)");
}
error = "no content (possibly caused by cache policy)";
} else {
request.setStatus("loaded", WorkflowJob.STATUS_RUNNING);
final String storedFailMessage = CrawlQueues.this.sb.toIndexer(response);
request.setStatus("enqueued-" + ((storedFailMessage == null) ? "ok" : "fail"), WorkflowJob.STATUS_FINISHED);
error = (storedFailMessage == null) ? null : "not enqueued to indexer: " + storedFailMessage;
}
} catch (final IOException e) {
request.setStatus("error", WorkflowJob.STATUS_FINISHED);
if (CrawlQueues.log.isFine()) {
CrawlQueues.log.fine("problem loading " + request.url().toString() + ": " + e.getMessage());
}
error = "load error - " + e.getMessage();
}
if (error != null) {
if (error.endsWith("$")) {
// the "$" mark at the end of the error message means, that the error was already pushed to the error-db by the reporting method
// thus we only push this message if we don't have that mark
error = error.substring(0, error.length() - 1).trim();
} else {
CrawlQueues.this.errorURL.push(request.url(), request.depth(), profile, FailCategory.TEMPORARY_NETWORK_FAILURE, "cannot load: " + error, -1);
}
request.setStatus("worker-error", WorkflowJob.STATUS_FINISHED);
} else {
request.setStatus("worker-processed", WorkflowJob.STATUS_FINISHED);
}
}
} catch (final Exception e) {
CrawlQueues.this.errorURL.push(request.url(), request.depth(), profile, FailCategory.TEMPORARY_NETWORK_FAILURE, e.getMessage() + " - in worker", -1);
request.setStatus("worker-exception", WorkflowJob.STATUS_FINISHED);
} finally {
request = null;
this.setName("CrawlQueues.Loader(WAITING)");
}
profile = null;
}
} catch (InterruptedException e2) {
ConcurrentLog.logException(e2);
}
}
}
}