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diff --git a/www/wiki/includes/jobqueue/jobs/HTMLCacheUpdateJob.php b/www/wiki/includes/jobqueue/jobs/HTMLCacheUpdateJob.php
new file mode 100644
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+++ b/www/wiki/includes/jobqueue/jobs/HTMLCacheUpdateJob.php
@@ -0,0 +1,202 @@
+<?php
+/**
+ * HTML cache invalidation of all pages linking to a given title.
+ *
+ * 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
+ * @ingroup Cache
+ */
+
+use MediaWiki\MediaWikiServices;
+
+/**
+ * Job to purge the cache for all pages that link to or use another page or file
+ *
+ * This job comes in a few variants:
+ *   - a) Recursive jobs to purge caches for backlink pages for a given title.
+ *        These jobs have (recursive:true,table:<table>) set.
+ *   - b) Jobs to purge caches for a set of titles (the job title is ignored).
+ *        These jobs have (pages:(<page ID>:(<namespace>,<title>),...) set.
+ *
+ * @ingroup JobQueue
+ */
+class HTMLCacheUpdateJob extends Job {
+	function __construct( Title $title, array $params ) {
+		parent::__construct( 'htmlCacheUpdate', $title, $params );
+		// Avoid the overhead of de-duplication when it would be pointless.
+		// Note that these jobs always set page_touched to the current time,
+		// so letting the older existing job "win" is still correct.
+		$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 Title to purge backlink pages from
+	 * @param string $table Backlink table name
+	 * @param array $params Additional job parameters
+	 * @return HTMLCacheUpdateJob
+	 */
+	public static function newForBacklinks( Title $title, $table, $params = [] ) {
+		return new self(
+			$title,
+			[
+				'table' => $table,
+				'recursive' => true
+			] + Job::newRootJobParams( // "overall" refresh links job info
+				"htmlCacheUpdate:{$table}:{$title->getPrefixedText()}"
+			) + $params
+		);
+	}
+
+	function run() {
+		global $wgUpdateRowsPerJob, $wgUpdateRowsPerQuery;
+
+		if ( isset( $this->params['table'] ) && !isset( $this->params['pages'] ) ) {
+			$this->params['recursive'] = true; // b/c; base job
+		}
+
+		// Job to purge all (or a range of) backlink pages for a page
+		if ( !empty( $this->params['recursive'] ) ) {
+			// Carry over information for de-duplication
+			$extraParams = $this->getRootJobParams();
+			// Carry over cause information for logging
+			$extraParams['causeAction'] = $this->params['causeAction'];
+			$extraParams['causeAgent'] = $this->params['causeAgent'];
+			// Convert this into no more than $wgUpdateRowsPerJob HTMLCacheUpdateJob per-title
+			// jobs and possibly a recursive HTMLCacheUpdateJob job for the rest of the backlinks
+			$jobs = BacklinkJobUtils::partitionBacklinkJob(
+				$this,
+				$wgUpdateRowsPerJob,
+				$wgUpdateRowsPerQuery, // jobs-per-title
+				// Carry over information for de-duplication
+				[ 'params' => $extraParams ]
+			);
+			JobQueueGroup::singleton()->push( $jobs );
+		// Job to purge pages for a set of titles
+		} elseif ( isset( $this->params['pages'] ) ) {
+			$this->invalidateTitles( $this->params['pages'] );
+		// Job to update a single title
+		} else {
+			$t = $this->title;
+			$this->invalidateTitles( [
+				$t->getArticleID() => [ $t->getNamespace(), $t->getDBkey() ]
+			] );
+		}
+
+		return true;
+	}
+
+	/**
+	 * @param array $pages Map of (page ID => (namespace, DB key)) entries
+	 */
+	protected function invalidateTitles( array $pages ) {
+		global $wgUpdateRowsPerQuery, $wgUseFileCache, $wgPageLanguageUseDB;
+
+		// Get all page IDs in this query into an array
+		$pageIds = array_keys( $pages );
+		if ( !$pageIds ) {
+			return;
+		}
+
+		// Bump page_touched to the current timestamp. This used to use the root job timestamp
+		// (e.g. template/file edit time), which was a bit more efficient when template edits are
+		// rare and don't effect the same pages much. However, this way allows for better
+		// de-duplication, which is much more useful for wikis with high edit rates. Note that
+		// RefreshLinksJob, which is enqueued alongside HTMLCacheUpdateJob, saves the parser output
+		// since it has to parse anyway. We assume that vast majority of the cache jobs finish
+		// before the link jobs, so using the current timestamp instead of the root timestamp is
+		// not expected to invalidate these cache entries too often.
+		$touchTimestamp = wfTimestampNow();
+		// If page_touched is higher than this, then something else already bumped it after enqueue
+		$condTimestamp = isset( $this->params['rootJobTimestamp'] )
+			? $this->params['rootJobTimestamp']
+			: $touchTimestamp;
+
+		$dbw = wfGetDB( DB_MASTER );
+		$factory = MediaWikiServices::getInstance()->getDBLoadBalancerFactory();
+		$ticket = $factory->getEmptyTransactionTicket( __METHOD__ );
+		// Update page_touched (skipping pages already touched since the root job).
+		// Check $wgUpdateRowsPerQuery for sanity; batch jobs are sized by that already.
+		foreach ( array_chunk( $pageIds, $wgUpdateRowsPerQuery ) as $batch ) {
+			$factory->commitAndWaitForReplication( __METHOD__, $ticket );
+
+			$dbw->update( 'page',
+				[ 'page_touched' => $dbw->timestamp( $touchTimestamp ) ],
+				[ 'page_id' => $batch,
+					// don't invalidated pages that were already invalidated
+					"page_touched < " . $dbw->addQuotes( $dbw->timestamp( $condTimestamp ) )
+				],
+				__METHOD__
+			);
+		}
+		// Get the list of affected pages (races only mean something else did the purge)
+		$titleArray = TitleArray::newFromResult( $dbw->select(
+			'page',
+			array_merge(
+				[ 'page_namespace', 'page_title' ],
+				$wgPageLanguageUseDB ? [ 'page_lang' ] : []
+			),
+			[ 'page_id' => $pageIds, 'page_touched' => $dbw->timestamp( $touchTimestamp ) ],
+			__METHOD__
+		) );
+
+		// Update CDN; call purge() directly so as to not bother with secondary purges
+		$urls = [];
+		foreach ( $titleArray as $title ) {
+			/** @var Title $title */
+			$urls = array_merge( $urls, $title->getCdnUrls() );
+		}
+		CdnCacheUpdate::purge( $urls );
+
+		// Update file cache
+		if ( $wgUseFileCache ) {
+			foreach ( $titleArray as $title ) {
+				HTMLFileCache::clearFileCache( $title );
+			}
+		}
+	}
+
+	public function getDeduplicationInfo() {
+		$info = parent::getDeduplicationInfo();
+		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 purged
+		} elseif ( isset( $this->params['pages'] ) ) {
+			return count( $this->params['pages'] );
+		}
+
+		return 1; // one title
+	}
+}