summaryrefslogtreecommitdiff
path: root/www/wiki/includes/jobqueue/jobs/RefreshLinksJob.php
diff options
context:
space:
mode:
Diffstat (limited to 'www/wiki/includes/jobqueue/jobs/RefreshLinksJob.php')
-rw-r--r--www/wiki/includes/jobqueue/jobs/RefreshLinksJob.php320
1 files changed, 320 insertions, 0 deletions
diff --git a/www/wiki/includes/jobqueue/jobs/RefreshLinksJob.php b/www/wiki/includes/jobqueue/jobs/RefreshLinksJob.php
new file mode 100644
index 00000000..8854c656
--- /dev/null
+++ b/www/wiki/includes/jobqueue/jobs/RefreshLinksJob.php
@@ -0,0 +1,320 @@
+<?php
+/**
+ * Job to update link tables for pages
+ *
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ * @ingroup JobQueue
+ */
+use MediaWiki\MediaWikiServices;
+use Wikimedia\Rdbms\DBReplicationWaitError;
+
+/**
+ * Job to update link tables for pages
+ *
+ * This job comes in a few variants:
+ * - a) Recursive jobs to update links for backlink pages for a given title.
+ * These jobs have (recursive:true,table:<table>) set.
+ * - b) Jobs to update links for a set of pages (the job title is ignored).
+ * These jobs have (pages:(<page ID>:(<namespace>,<title>),...) set.
+ * - c) Jobs to update links for a single page (the job title)
+ * These jobs need no extra fields set.
+ *
+ * @ingroup JobQueue
+ */
+class RefreshLinksJob extends Job {
+ /** @var float Cache parser output when it takes this long to render */
+ const PARSE_THRESHOLD_SEC = 1.0;
+ /** @var int Lag safety margin when comparing root job times to last-refresh times */
+ const CLOCK_FUDGE = 10;
+ /** @var int How many seconds to wait for replica DBs to catch up */
+ const LAG_WAIT_TIMEOUT = 15;
+
+ function __construct( Title $title, array $params ) {
+ parent::__construct( 'refreshLinks', $title, $params );
+ // Avoid the overhead of de-duplication when it would be pointless
+ $this->removeDuplicates = (
+ // Ranges rarely will line up
+ !isset( $params['range'] ) &&
+ // Multiple pages per job make matches unlikely
+ !( isset( $params['pages'] ) && count( $params['pages'] ) != 1 )
+ );
+ $this->params += [ 'causeAction' => 'unknown', 'causeAgent' => 'unknown' ];
+ }
+
+ /**
+ * @param Title $title
+ * @param array $params
+ * @return RefreshLinksJob
+ */
+ public static function newPrioritized( Title $title, array $params ) {
+ $job = new self( $title, $params );
+ $job->command = 'refreshLinksPrioritized';
+
+ return $job;
+ }
+
+ /**
+ * @param Title $title
+ * @param array $params
+ * @return RefreshLinksJob
+ */
+ public static function newDynamic( Title $title, array $params ) {
+ $job = new self( $title, $params );
+ $job->command = 'refreshLinksDynamic';
+
+ return $job;
+ }
+
+ function run() {
+ global $wgUpdateRowsPerJob;
+
+ // Job to update all (or a range of) backlink pages for a page
+ if ( !empty( $this->params['recursive'] ) ) {
+ // When the base job branches, wait for the replica DBs to catch up to the master.
+ // From then on, we know that any template changes at the time the base job was
+ // enqueued will be reflected in backlink page parses when the leaf jobs run.
+ if ( !isset( $this->params['range'] ) ) {
+ try {
+ $lbFactory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
+ $lbFactory->waitForReplication( [
+ 'wiki' => wfWikiID(),
+ 'timeout' => self::LAG_WAIT_TIMEOUT
+ ] );
+ } catch ( DBReplicationWaitError $e ) { // only try so hard
+ $stats = MediaWikiServices::getInstance()->getStatsdDataFactory();
+ $stats->increment( 'refreshlinks.lag_wait_failed' );
+ }
+ }
+ // Carry over information for de-duplication
+ $extraParams = $this->getRootJobParams();
+ $extraParams['triggeredRecursive'] = true;
+ // Carry over cause information for logging
+ $extraParams['causeAction'] = $this->params['causeAction'];
+ $extraParams['causeAgent'] = $this->params['causeAgent'];
+ // Convert this into no more than $wgUpdateRowsPerJob RefreshLinks per-title
+ // jobs and possibly a recursive RefreshLinks job for the rest of the backlinks
+ $jobs = BacklinkJobUtils::partitionBacklinkJob(
+ $this,
+ $wgUpdateRowsPerJob,
+ 1, // job-per-title
+ [ 'params' => $extraParams ]
+ );
+ JobQueueGroup::singleton()->push( $jobs );
+ // Job to update link tables for a set of titles
+ } elseif ( isset( $this->params['pages'] ) ) {
+ foreach ( $this->params['pages'] as $nsAndKey ) {
+ list( $ns, $dbKey ) = $nsAndKey;
+ $this->runForTitle( Title::makeTitleSafe( $ns, $dbKey ) );
+ }
+ // Job to update link tables for a given title
+ } else {
+ $this->runForTitle( $this->title );
+ }
+
+ return true;
+ }
+
+ /**
+ * @param Title $title
+ * @return bool
+ */
+ protected function runForTitle( Title $title ) {
+ $services = MediaWikiServices::getInstance();
+ $stats = $services->getStatsdDataFactory();
+ $lbFactory = $services->getDBLoadBalancerFactory();
+ $ticket = $lbFactory->getEmptyTransactionTicket( __METHOD__ );
+
+ $page = WikiPage::factory( $title );
+ $page->loadPageData( WikiPage::READ_LATEST );
+
+ // Serialize links updates by page ID so they see each others' changes
+ $dbw = $lbFactory->getMainLB()->getConnection( DB_MASTER );
+ /** @noinspection PhpUnusedLocalVariableInspection */
+ $scopedLock = LinksUpdate::acquirePageLock( $dbw, $page->getId(), 'job' );
+ // Get the latest ID *after* acquirePageLock() flushed the transaction.
+ // This is used to detect edits/moves after loadPageData() but before the scope lock.
+ // The works around the chicken/egg problem of determining the scope lock key.
+ $latest = $title->getLatestRevID( Title::GAID_FOR_UPDATE );
+
+ if ( !empty( $this->params['triggeringRevisionId'] ) ) {
+ // Fetch the specified revision; lockAndGetLatest() below detects if the page
+ // was edited since and aborts in order to avoid corrupting the link tables
+ $revision = Revision::newFromId(
+ $this->params['triggeringRevisionId'],
+ Revision::READ_LATEST
+ );
+ } else {
+ // Fetch current revision; READ_LATEST reduces lockAndGetLatest() check failures
+ $revision = Revision::newFromTitle( $title, false, Revision::READ_LATEST );
+ }
+
+ if ( !$revision ) {
+ $stats->increment( 'refreshlinks.rev_not_found' );
+ $this->setLastError( "Revision not found for {$title->getPrefixedDBkey()}" );
+ return false; // just deleted?
+ } elseif ( $revision->getId() != $latest || $revision->getPage() !== $page->getId() ) {
+ // Do not clobber over newer updates with older ones. If all jobs where FIFO and
+ // serialized, it would be OK to update links based on older revisions since it
+ // would eventually get to the latest. Since that is not the case (by design),
+ // only update the link tables to a state matching the current revision's output.
+ $stats->increment( 'refreshlinks.rev_not_current' );
+ $this->setLastError( "Revision {$revision->getId()} is not current" );
+ return false;
+ }
+
+ $content = $revision->getContent( Revision::RAW );
+ if ( !$content ) {
+ // If there is no content, pretend the content is empty
+ $content = $revision->getContentHandler()->makeEmptyContent();
+ }
+
+ $parserOutput = false;
+ $parserOptions = $page->makeParserOptions( 'canonical' );
+ // If page_touched changed after this root job, then it is likely that
+ // any views of the pages already resulted in re-parses which are now in
+ // cache. The cache can be reused to avoid expensive parsing in some cases.
+ if ( isset( $this->params['rootJobTimestamp'] ) ) {
+ $opportunistic = !empty( $this->params['isOpportunistic'] );
+
+ $skewedTimestamp = $this->params['rootJobTimestamp'];
+ if ( $opportunistic ) {
+ // Neither clock skew nor DB snapshot/replica DB lag matter much for such
+ // updates; focus on reusing the (often recently updated) cache
+ } else {
+ // For transclusion updates, the template changes must be reflected
+ $skewedTimestamp = wfTimestamp( TS_MW,
+ wfTimestamp( TS_UNIX, $skewedTimestamp ) + self::CLOCK_FUDGE
+ );
+ }
+
+ if ( $page->getLinksTimestamp() > $skewedTimestamp ) {
+ // Something already updated the backlinks since this job was made
+ $stats->increment( 'refreshlinks.update_skipped' );
+ return true;
+ }
+
+ if ( $page->getTouched() >= $this->params['rootJobTimestamp'] || $opportunistic ) {
+ // Cache is suspected to be up-to-date. As long as the cache rev ID matches
+ // and it reflects the job's triggering change, then it is usable.
+ $parserOutput = $services->getParserCache()->getDirty( $page, $parserOptions );
+ if ( !$parserOutput
+ || $parserOutput->getCacheRevisionId() != $revision->getId()
+ || $parserOutput->getCacheTime() < $skewedTimestamp
+ ) {
+ $parserOutput = false; // too stale
+ }
+ }
+ }
+
+ // Fetch the current revision and parse it if necessary...
+ if ( $parserOutput ) {
+ $stats->increment( 'refreshlinks.parser_cached' );
+ } else {
+ $start = microtime( true );
+ // Revision ID must be passed to the parser output to get revision variables correct
+ $parserOutput = $content->getParserOutput(
+ $title, $revision->getId(), $parserOptions, false );
+ $elapsed = microtime( true ) - $start;
+ // If it took a long time to render, then save this back to the cache to avoid
+ // wasted CPU by other apaches or job runners. We don't want to always save to
+ // cache as this can cause high cache I/O and LRU churn when a template changes.
+ if ( $elapsed >= self::PARSE_THRESHOLD_SEC
+ && $page->shouldCheckParserCache( $parserOptions, $revision->getId() )
+ && $parserOutput->isCacheable()
+ ) {
+ $ctime = wfTimestamp( TS_MW, (int)$start ); // cache time
+ $services->getParserCache()->save(
+ $parserOutput, $page, $parserOptions, $ctime, $revision->getId()
+ );
+ }
+ $stats->increment( 'refreshlinks.parser_uncached' );
+ }
+
+ $updates = $content->getSecondaryDataUpdates(
+ $title,
+ null,
+ !empty( $this->params['useRecursiveLinksUpdate'] ),
+ $parserOutput
+ );
+
+ // For legacy hook handlers doing updates via LinksUpdateConstructed, make sure
+ // any pending writes they made get flushed before the doUpdate() calls below.
+ // This avoids snapshot-clearing errors in LinksUpdate::acquirePageLock().
+ $lbFactory->commitAndWaitForReplication( __METHOD__, $ticket );
+
+ foreach ( $updates as $update ) {
+ // Carry over cause in case so the update can do extra logging
+ $update->setCause( $this->params['causeAction'], $this->params['causeAgent'] );
+ // FIXME: This code probably shouldn't be here?
+ // Needed by things like Echo notifications which need
+ // to know which user caused the links update
+ if ( $update instanceof LinksUpdate ) {
+ $update->setRevision( $revision );
+ if ( !empty( $this->params['triggeringUser'] ) ) {
+ $userInfo = $this->params['triggeringUser'];
+ if ( $userInfo['userId'] ) {
+ $user = User::newFromId( $userInfo['userId'] );
+ } else {
+ // Anonymous, use the username
+ $user = User::newFromName( $userInfo['userName'], false );
+ }
+ $update->setTriggeringUser( $user );
+ }
+ }
+ }
+
+ foreach ( $updates as $update ) {
+ $update->setTransactionTicket( $ticket );
+ $update->doUpdate();
+ }
+
+ InfoAction::invalidateCache( $title );
+
+ // Commit any writes here in case this method is called in a loop.
+ // In that case, the scoped lock will fail to be acquired.
+ $lbFactory->commitAndWaitForReplication( __METHOD__, $ticket );
+
+ return true;
+ }
+
+ public function getDeduplicationInfo() {
+ $info = parent::getDeduplicationInfo();
+ unset( $info['causeAction'] );
+ unset( $info['causeAgent'] );
+ if ( is_array( $info['params'] ) ) {
+ // For per-pages jobs, the job title is that of the template that changed
+ // (or similar), so remove that since it ruins duplicate detection
+ if ( isset( $info['params']['pages'] ) ) {
+ unset( $info['namespace'] );
+ unset( $info['title'] );
+ }
+ }
+
+ return $info;
+ }
+
+ public function workItemCount() {
+ if ( !empty( $this->params['recursive'] ) ) {
+ return 0; // nothing actually refreshed
+ } elseif ( isset( $this->params['pages'] ) ) {
+ return count( $this->params['pages'] );
+ }
+
+ return 1; // one title
+ }
+}
generated by cgit v1.2.1 (git 2.18.0) at 2024-05-05 02:00:59 +0000