Only store currently-existing categories in the categories table

[mediawiki.git] / includes / poolcounter / PoolWorkArticleView.php

<?php
/**
 * 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
 */

class PoolWorkArticleView extends PoolCounterWork {
        /** @var WikiPage */
        private $page;

        /** @var string */
        private $cacheKey;

        /** @var int */
        private $revid;

        /** @var ParserOptions */
        private $parserOptions;

        /** @var Content|null */
        private $content = null;

        /** @var ParserOutput|bool */
        private $parserOutput = false;

        /** @var bool */
        private $isDirty = false;

        /** @var Status|bool */
        private $error = false;

        /**
         * @param WikiPage $page
         * @param ParserOptions $parserOptions ParserOptions to use for the parse
         * @param int $revid ID of the revision being parsed.
         * @param bool $useParserCache Whether to use the parser cache.
         *   operation.
         * @param Content|string $content Content to parse or null to load it; may
         *   also be given as a wikitext string, for BC.
         */
        public function __construct( WikiPage $page, ParserOptions $parserOptions,
                $revid, $useParserCache, $content = null
        ) {
                if ( is_string( $content ) ) { // BC: old style call
                        $modelId = $page->getRevision()->getContentModel();
                        $format = $page->getRevision()->getContentFormat();
                        $content = ContentHandler::makeContent( $content, $page->getTitle(), $modelId, $format );
                }

                $this->page = $page;
                $this->revid = $revid;
                $this->cacheable = $useParserCache;
                $this->parserOptions = $parserOptions;
                $this->content = $content;
                $this->cacheKey = ParserCache::singleton()->getKey( $page, $parserOptions );
                $keyPrefix = $this->cacheKey ?: wfMemcKey( 'articleview', 'missingcachekey' );
                parent::__construct( 'ArticleView', $keyPrefix . ':revid:' . $revid );
        }

        /**
         * Get the ParserOutput from this object, or false in case of failure
         *
         * @return ParserOutput
         */
        public function getParserOutput() {
                return $this->parserOutput;
        }

        /**
         * Get whether the ParserOutput is a dirty one (i.e. expired)
         *
         * @return bool
         */
        public function getIsDirty() {
                return $this->isDirty;
        }

        /**
         * Get a Status object in case of error or false otherwise
         *
         * @return Status|bool
         */
        public function getError() {
                return $this->error;
        }

        /**
         * @return bool
         */
        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();

                if ( $this->content !== null ) {
                        $content = $this->content;
                } elseif ( $isCurrent ) {
                        // XXX: why use RAW audience here, and PUBLIC (default) below?
                        $content = $this->page->getContent( Revision::RAW );
                } else {
                        $rev = Revision::newFromTitle( $this->page->getTitle(), $this->revid );

                        if ( $rev === null ) {
                                $content = null;
                        } else {
                                // XXX: why use PUBLIC audience here (default), and RAW above?
                                $content = $rev->getContent();
                        }
                }

                if ( $content === null ) {
                        return false;
                }

                // Reduce effects of race conditions for slow parses (bug 46014)
                $cacheTime = wfTimestampNow();

                $time = - microtime( true );
                $this->parserOutput = $content->getParserOutput(
                        $this->page->getTitle(),
                        $this->revid,
                        $this->parserOptions
                );
                $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(),
                                'trigger' => 'view',
                        ] );
                }

                if ( $this->cacheable && $this->parserOutput->isCacheable() && $isCurrent ) {
                        ParserCache::singleton()->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;
        }

        /**
         * @return bool
         */
        public function getCachedWork() {
                $this->parserOutput = ParserCache::singleton()->get( $this->page, $this->parserOptions );

                if ( $this->parserOutput === false ) {
                        wfDebug( __METHOD__ . ": parser cache miss\n" );
                        return false;
                } else {
                        wfDebug( __METHOD__ . ": parser cache hit\n" );
                        return true;
                }
        }

        /**
         * @return bool
         */
        public function fallback() {
                $this->parserOutput = ParserCache::singleton()->getDirty( $this->page, $this->parserOptions );

                if ( $this->parserOutput === false ) {
                        wfDebugLog( 'dirty', 'dirty missing' );
                        wfDebug( __METHOD__ . ": no dirty cache\n" );
                        return false;
                } else {
                        wfDebug( __METHOD__ . ": sending dirty output\n" );
                        wfDebugLog( 'dirty', "dirty output {$this->cacheKey}" );
                        $this->isDirty = true;
                        return true;
                }
        }

        /**
         * @param Status $status
         * @return bool
         */
        public function error( $status ) {
                $this->error = $status;
                return false;
        }
}