RefreshLinksJob.php

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<?php
class RefreshLinksJob extends Job {
        function __construct( $title, $params = '', $id = 0 ) {
                parent::__construct( 'refreshLinks', $title, $params, $id );
                $this->removeDuplicates = true; // job is expensive
        }

        function run() {
                wfProfileIn( __METHOD__ );

                $linkCache = LinkCache::singleton();
                $linkCache->clear();

                if ( is_null( $this->title ) ) {
                        $this->error = "refreshLinks: Invalid title";
                        wfProfileOut( __METHOD__ );
                        return false;
                }

                # Wait for the DB of the current/next slave DB handle to catch up to the master.
                # This way, we get the correct page_latest for templates or files that just changed
                # milliseconds ago, having triggered this job to begin with.
                if ( isset( $this->params['masterPos'] ) ) {
                        wfGetLB()->waitFor( $this->params['masterPos'] );
                }

                $revision = Revision::newFromTitle( $this->title, false, Revision::READ_NORMAL );
                if ( !$revision ) {
                        $this->error = 'refreshLinks: Article not found "' .
                                $this->title->getPrefixedDBkey() . '"';
                        wfProfileOut( __METHOD__ );
                        return false; // XXX: what if it was just deleted?
                }

                self::runForTitleInternal( $this->title, $revision, __METHOD__ );

                wfProfileOut( __METHOD__ );
                return true;
        }

        public function getDeduplicationInfo() {
                $info = parent::getDeduplicationInfo();
                // Don't let highly unique "masterPos" values ruin duplicate detection
                if ( is_array( $info['params'] ) ) {
                        unset( $info['params']['masterPos'] );
                }
                return $info;
        }

        public static function runForTitleInternal( Title $title, Revision $revision, $fname ) {
                wfProfileIn( $fname );
                $content = $revision->getContent( Revision::RAW );

                if ( !$content ) {
                        // if there is no content, pretend the content is empty
                        $content = $revision->getContentHandler()->makeEmptyContent();
                }

                // Revision ID must be passed to the parser output to get revision variables correct
                $parserOutput = $content->getParserOutput( $title, $revision->getId(), null, false );

                $updates = $content->getSecondaryDataUpdates( $title, null, false, $parserOutput );
                DataUpdate::runUpdates( $updates );
                wfProfileOut( $fname );
        }
}

class RefreshLinksJob2 extends Job {
        function __construct( $title, $params, $id = 0 ) {
                parent::__construct( 'refreshLinks2', $title, $params, $id );
        }

        function run() {
                global $wgUpdateRowsPerJob;

                wfProfileIn( __METHOD__ );

                $linkCache = LinkCache::singleton();
                $linkCache->clear();

                if ( is_null( $this->title ) ) {
                        $this->error = "refreshLinks2: Invalid title";
                        wfProfileOut( __METHOD__ );
                        return false;
                }

                // Back compat for pre-r94435 jobs
                $table = isset( $this->params['table'] ) ? $this->params['table'] : 'templatelinks';

                // Avoid slave lag when fetching templates.
                // When the outermost job is run, we know that the caller that enqueued it must have
                // committed the relevant changes to the DB by now. At that point, record the master
                // position and pass it along as the job recursively breaks into smaller range jobs.
                // Hopefully, when leaf jobs are popped, the slaves will have reached that position.
                if ( isset( $this->params['masterPos'] ) ) {
                        $masterPos = $this->params['masterPos'];
                } elseif ( wfGetLB()->getServerCount() > 1  ) {
                        $masterPos = wfGetLB()->getMasterPos();
                } else {
                        $masterPos = false;
                }

                $tbc = $this->title->getBacklinkCache();

                $jobs = array(); // jobs to insert
                if ( isset( $this->params['start'] ) && isset( $this->params['end'] ) ) {
                        # This is a partition job to trigger the insertion of leaf jobs...
                        $jobs = array_merge( $jobs, $this->getSingleTitleJobs( $table, $masterPos ) );
                } else {
                        # This is a base job to trigger the insertion of partitioned jobs...
                        if ( $tbc->getNumLinks( $table ) <= $wgUpdateRowsPerJob ) {
                                # Just directly insert the single per-title jobs
                                $jobs = array_merge( $jobs, $this->getSingleTitleJobs( $table, $masterPos ) );
                        } else {
                                # Insert the partition jobs to make per-title jobs
                                foreach ( $tbc->partition( $table, $wgUpdateRowsPerJob ) as $batch ) {
                                        list( $start, $end ) = $batch;
                                        $jobs[] = new RefreshLinksJob2( $this->title,
                                                array(
                                                        'table'            => $table,
                                                        'start'            => $start,
                                                        'end'              => $end,
                                                        'masterPos'        => $masterPos,
                                                ) + $this->getRootJobParams() // carry over information for de-duplication
                                        );
                                }
                        }
                }

                if ( count( $jobs ) ) {
                        JobQueueGroup::singleton()->push( $jobs );
                }

                wfProfileOut( __METHOD__ );
                return true;
        }

        protected function getSingleTitleJobs( $table, $masterPos ) {
                # The "start"/"end" fields are not set for the base jobs
                $start = isset( $this->params['start'] ) ? $this->params['start'] : false;
                $end = isset( $this->params['end'] ) ? $this->params['end'] : false;
                $titles = $this->title->getBacklinkCache()->getLinks( $table, $start, $end );
                # Convert into single page refresh links jobs.
                # This handles well when in sapi mode and is useful in any case for job
                # de-duplication. If many pages use template A, and that template itself
                # uses template B, then an edit to both will create many duplicate jobs.
                # Roughly speaking, for each page, one of the "RefreshLinksJob" jobs will
                # get run first, and when it does, it will remove the duplicates. Of course,
                # one page could have its job popped when the other page's job is still
                # buried within the logic of a refreshLinks2 job.
                $jobs = array();
                foreach ( $titles as $title ) {
                        $jobs[] = new RefreshLinksJob( $title,
                                array( 'masterPos' => $masterPos ) + $this->getRootJobParams()
                        ); // carry over information for de-duplication
                }
                return $jobs;
        }

        public function getDeduplicationInfo() {
                $info = parent::getDeduplicationInfo();
                // Don't let highly unique "masterPos" values ruin duplicate detection
                if ( is_array( $info['params'] ) ) {
                        unset( $info['params']['masterPos'] );
                }
                return $info;
        }
}