PoolWorkArticleView.php

Go to the documentation of this file.

<?php
use MediaWiki\MediaWikiServices;
use MediaWiki\Revision\MutableRevisionRecord;
use MediaWiki\Revision\RevisionRecord;
use MediaWiki\Revision\RevisionRenderer;
use MediaWiki\Revision\RevisionStore;
use MediaWiki\Revision\SlotRecord;
 
class PoolWorkArticleView extends PoolCounterWork {
    private $page;
 
    private $cacheKey;
 
    private $revid;
 
    private $parserCache;
 
    private $parserOptions;
 
    private $revision = null;
 
    private $audience;
 
    private $revisionStore = null;
 
    private $renderer = null;
 
    private $parserOutput = false;
 
    private $isDirty = false;
 
    private $isFast = false;
 
    private $error = false;
 
    public function __construct( WikiPage $page, ParserOptions $parserOptions,
        $revid, $useParserCache, $revision = null, $audience = RevisionRecord::FOR_PUBLIC
    ) {
        if ( is_string( $revision ) ) { // BC: very old style call
            $revRecord = $page->getRevisionRecord();
            $mainSlot = $revRecord->getSlot( SlotRecord::MAIN, RevisionRecord::RAW );
            $modelId = $mainSlot->getModel();
            $format = $mainSlot->getFormat();
 
            if ( $format === null ) {
                $format = MediaWikiServices::getInstance()
                    ->getContentHandlerFactory()
                    ->getContentHandler( $modelId )
                    ->getDefaultFormat();
            }
 
            $revision = ContentHandler::makeContent( $revision, $page->getTitle(), $modelId, $format );
        }
 
        if ( $revision instanceof Content ) { // BC: old style call
            $content = $revision;
            $revision = new MutableRevisionRecord( $page->getTitle() );
            $revision->setId( $revid );
            $revision->setPageId( $page->getId() );
            $revision->setContent( SlotRecord::MAIN, $content );
        }
 
        if ( $revision ) {
            // Check that the RevisionRecord matches $revid and $page, but still allow
            // fake RevisionRecords coming from errors or hooks in Article to be rendered.
            if ( $revision->getId() && $revision->getId() !== $revid ) {
                throw new InvalidArgumentException( '$revid parameter mismatches $revision parameter' );
            }
            if ( $revision->getPageId()
                && $revision->getPageId() !== $page->getTitle()->getArticleID()
            ) {
                throw new InvalidArgumentException( '$page parameter mismatches $revision parameter' );
            }
        }
 
        // TODO: DI: inject services
        $this->renderer = MediaWikiServices::getInstance()->getRevisionRenderer();
        $this->revisionStore = MediaWikiServices::getInstance()->getRevisionStore();
        $this->parserCache = MediaWikiServices::getInstance()->getParserCache();
 
        $this->page = $page;
        $this->revid = $revid;
        $this->cacheable = $useParserCache;
        $this->parserOptions = $parserOptions;
        $this->revision = $revision;
        $this->audience = $audience;
        $this->cacheKey = $this->parserCache->getKey( $page, $parserOptions );
        $keyPrefix = $this->cacheKey ?: ObjectCache::getLocalClusterInstance()->makeKey(
            'articleview', 'missingcachekey'
        );
 
        parent::__construct( 'ArticleView', $keyPrefix . ':revid:' . $revid );
    }
 
    public function getParserOutput() {
        return $this->parserOutput;
    }
 
    public function getIsDirty() {
        return $this->isDirty;
    }
 
    public function getIsFastStale() {
        return $this->isFast;
    }
 
    public function getError() {
        return $this->error;
    }
 
    public function doWork() {
        global $wgUseFileCache;
 
        // @todo several of the methods called on $this->page are not declared in Page, but present
        //        in WikiPage and delegated by Article.
 
        $isCurrent = $this->revid === $this->page->getLatest();
 
        // The current revision cannot be hidden so we can skip some checks.
        $audience = $isCurrent ? RevisionRecord::RAW : $this->audience;
 
        if ( $this->revision !== null ) {
            $rev = $this->revision;
        } elseif ( $isCurrent ) {
            $rev = $this->page->getRevisionRecord();
        } else {
            $rev = $this->revisionStore->getRevisionByTitle( $this->page->getTitle(), $this->revid );
        }
 
        if ( !$rev ) {
            // couldn't load
            return false;
        }
 
        $renderedRevision = $this->renderer->getRenderedRevision(
            $rev,
            $this->parserOptions,
            null,
            [ 'audience' => $audience ]
        );
 
        if ( !$renderedRevision ) {
            // audience check failed
            return false;
        }
 
        // Reduce effects of race conditions for slow parses (T48014)
        $cacheTime = wfTimestampNow();
 
        $time = -microtime( true );
        $this->parserOutput = $renderedRevision->getRevisionParserOutput();
        $time += microtime( true );
 
        // Timing hack
        if ( $time > 3 ) {
            // TODO: Use Parser's logger (once it has one)
            $logger = MediaWiki\Logger\LoggerFactory::getInstance( 'slow-parse' );
            $logger->info( '{time} {title}', [
                'time' => number_format( $time, 2 ),
                'title' => $this->page->getTitle()->getPrefixedDBkey(),
                'ns' => $this->page->getTitle()->getNamespace(),
                'trigger' => 'view',
            ] );
        }
 
        if ( $this->cacheable && $this->parserOutput->isCacheable() && $isCurrent ) {
            $this->parserCache->save(
                $this->parserOutput, $this->page, $this->parserOptions, $cacheTime, $this->revid );
        }
 
        // Make sure file cache is not used on uncacheable content.
        // Output that has magic words in it can still use the parser cache
        // (if enabled), though it will generally expire sooner.
        if ( !$this->parserOutput->isCacheable() ) {
            $wgUseFileCache = false;
        }
 
        if ( $isCurrent ) {
            $this->page->triggerOpportunisticLinksUpdate( $this->parserOutput );
        }
 
        return true;
    }
 
    public function getCachedWork() {
        $this->parserOutput = $this->parserCache->get( $this->page, $this->parserOptions );
 
        if ( $this->parserOutput === false ) {
            wfDebug( __METHOD__ . ": parser cache miss" );
            return false;
        } else {
            wfDebug( __METHOD__ . ": parser cache hit" );
            return true;
        }
    }
 
    public function fallback( $fast ) {
        $this->parserOutput = $this->parserCache->getDirty( $this->page, $this->parserOptions );
 
        $fastMsg = '';
        if ( $this->parserOutput && $fast ) {
            /* Check if the stale response is from before the last write to the
             * DB by this user. Declining to return a stale response in this
             * case ensures that the user will see their own edit after page
             * save.
             *
             * Note that the CP touch time is the timestamp of the shutdown of
             * the save request, so there is a bias towards avoiding fast stale
             * responses of potentially several seconds.
             */
            $lastWriteTime = MediaWikiServices::getInstance()->getDBLoadBalancerFactory()
                ->getChronologyProtectorTouched();
            $cacheTime = MWTimestamp::convert( TS_UNIX, $this->parserOutput->getCacheTime() );
            if ( $lastWriteTime && $cacheTime <= $lastWriteTime ) {
                wfDebugLog( 'dirty', "declining to send dirty output since cache time " .
                    $cacheTime . " is before last write time $lastWriteTime" );
                // Forget this ParserOutput -- we will request it again if
                // necessary in slow mode. There might be a newer entry
                // available by that time.
                $this->parserOutput = false;
                return false;
            }
            $this->isFast = true;
            $fastMsg = 'fast ';
        }
 
        if ( $this->parserOutput === false ) {
            wfDebugLog( 'dirty', 'dirty missing' );
            return false;
        } else {
            wfDebugLog( 'dirty', "{$fastMsg}dirty output {$this->cacheKey}" );
            $this->isDirty = true;
            return true;
        }
    }
 
    public function error( $status ) {
        $this->error = $status;
        return false;
    }
}