1 files changed, 143 insertions, 0 deletions
diff --git a/www/wiki/extensions/SemanticMediaWiki/src/MediaWiki/Hooks/ArticleDelete.php b/www/wiki/extensions/SemanticMediaWiki/src/MediaWiki/Hooks/ArticleDelete.php
new file mode 100644
index 00000000..5d77c30d
--- /dev/null
+++ b/www/wiki/extensions/SemanticMediaWiki/src/MediaWiki/Hooks/ArticleDelete.php
@@ -0,0 +1,143 @@
+<?php
+
+namespace SMW\MediaWiki\Hooks;
+
+use SMW\ApplicationFactory;
+use SMW\DIWikiPage;
+use SMW\EventHandler;
+use SMW\MediaWiki\Jobs\UpdateDispatcherJob;
+use SMW\SemanticData;
+use SMW\Store;
+use Title;
+use Wikipage;
+
+/**
+ * @see https://www.mediawiki.org/wiki/Manual:Hooks/ArticleDelete
+ *
+ * @license GNU GPL v2+
+ * @since 2.0
+ *
+ * @author mwjames
+ */
+class ArticleDelete extends HookHandler {
+
+	/**
+	 * @var
+	 */
+	private $store;
+
+	/**
+	 * @since 3.0
+	 *
+	 * @param Store $store
+	 */
+	public function __construct( Store $store ) {
+		$this->store = $store;
+	}
+
+	/**
+	 * @since 2.0
+	 *
+	 * @param Wikipage $wikiPage
+	 *
+	 * @return true
+	 */
+	public function process( Wikipage $wikiPage ) {
+
+		$deferredCallableUpdate = ApplicationFactory::getInstance()->newDeferredCallableUpdate( function() use( $wikiPage ) {
+			$this->doDelete( $wikiPage->getTitle() );
+		} );
+
+		$deferredCallableUpdate->setOrigin( __METHOD__ );
+		$deferredCallableUpdate->pushUpdate();
+
+		return true;
+	}
+
+	/**
+	 * @since 3.0
+	 *
+	 * @param Title $title
+	 */
+	public function doDelete( Title $title ) {
+
+		$applicationFactory = ApplicationFactory::getInstance();
+		$subject = DIWikiPage::newFromTitle( $title );
+
+		$semanticDataSerializer = $applicationFactory->newSerializerFactory()->newSemanticDataSerializer();
+		$jobFactory = $applicationFactory->newJobFactory();
+
+		// Instead of Store::getSemanticData, construct the SemanticData by
+		// attaching only the incoming properties indicating which entities
+		// carry an actual reference to this subject
+		$semanticData = new SemanticData(
+			$subject
+		);
+
+		$properties = $this->store->getInProperties( $subject );
+
+		foreach ( $properties as $property ) {
+			// Avoid doing $propertySubjects = $store->getPropertySubjects( $property, $subject );
+			// as it may produce a too large pool of entities and ultimately
+			// block the delete transaction
+			// Use the subject as dataItem with the UpdateDispatcherJob because
+			// Store::getAllPropertySubjects is only scanning the property
+			$semanticData->addPropertyObjectValue( $property, $subject );
+		}
+
+		$parameters['semanticData'] = $semanticDataSerializer->serialize(
+			$semanticData
+		);
+
+		$parameters['origin'] = 'ArticleDelete';
+
+		// Fetch the ID before the delete process marks it as outdated to help
+		// run a dispatch process on secondary tables
+		$parameters['_id'] = $this->store->getObjectIds()->getId(
+			$subject
+		);
+
+		// Restricted to the available SemanticData
+		$parameters[UpdateDispatcherJob::RESTRICTED_DISPATCH_POOL] = true;
+
+		$updateDispatcherJob = $jobFactory->newUpdateDispatcherJob( $title, $parameters );
+		$updateDispatcherJob->insert();
+
+		$parserCachePurgeJob = $jobFactory->newParserCachePurgeJob(
+			$title,
+			[
+				'idlist' => [
+					$parameters['_id']
+				],
+				'origin' => 'ArticleDelete',
+
+				// Insert will only be done for when the links store is active
+				// otherwise the job wouldn't have any work to do
+				'is.enabled' => $this->getOption( 'smwgEnabledQueryDependencyLinksStore' )
+			]
+		);
+
+		$parserCachePurgeJob->insert();
+
+		$this->store->deleteSubject( $title );
+
+		$eventHandler = EventHandler::getInstance();
+		$dispatchContext = $eventHandler->newDispatchContext();
+
+		$dispatchContext->set( 'title', $title );
+		$dispatchContext->set( 'subject', $subject );
+		$dispatchContext->set( 'context', 'ArticleDelete' );
+
+		$eventHandler->getEventDispatcher()->dispatch(
+			'cached.prefetcher.reset',
+			$dispatchContext
+		);
+
+		// Removes any related update marker
+		$eventHandler->getEventDispatcher()->dispatch(
+			'cached.update.marker.delete',
+			$dispatchContext
+		);
+	}
+
+}