DomainEventEmitter: migrate logic from DerivedDataUpdater

Migrates the following updates from DerivedDataUpdater to ServiceWiring:
- SearchUpdate
- MessageCache

Bug: T378936
Change-Id: Ice7651900423e25f8c907c9f4c5e47085ef9edf0

1 files changed, 54 insertions, 0 deletions

diff --git a/includes/search/SearchEventIngress.php b/includes/search/SearchEventIngress.php
new file mode 100644
index 000000000000..fb275299c0c4
--- /dev/null
+++ b/includes/search/SearchEventIngress.php
@@ -0,0 +1,54 @@
+<?php
+
+namespace MediaWiki\Search;
+
+use MediaWiki\Deferred\SearchUpdate;
+use MediaWiki\DomainEvent\EventSubscriberBase;
+use MediaWiki\Revision\RevisionRecord;
+use MediaWiki\Revision\SlotRecord;
+use MediaWiki\Storage\PageUpdatedEvent;
+
+/**
+ * The ingres adapter for the search component. It updates search related state
+ * according to domain events coming from other components.
+ *
+ * @internal
+ */
+class SearchEventIngress extends EventSubscriberBase {
+
+	/** Object spec intented for use with {@link DomainEventSource::registerSubscriber()} */
+	public const OBJECT_SPEC = [
+		'class' => self::class,
+		'services' => [],
+		'events' => [
+			PageUpdatedEvent::TYPE
+		],
+	];
+
+	/**
+	 * Listener method for PageUpdatedEvent, to be registered with a DomainEventSource.
+	 *
+	 * @noinspection PhpUnused
+	 */
+	public function handlePageUpdatedEventAfterCommit( PageUpdatedEvent $event ) {
+		$newRevision = $event->getNewRevision();
+		$mainSlot = $newRevision->getSlot( SlotRecord::MAIN );
+		if (
+			!$mainSlot->isInherited() &&
+			!$newRevision->isDeleted( RevisionRecord::DELETED_TEXT )
+		) {
+			// NOTE: no need to go through DeferredUpdates,
+			// we are already deferred.
+			$update = new SearchUpdate(
+				$event->getPage()->getId(),
+				$event->getPage(),
+				$mainSlot->getContent()
+			);
+
+			// No need to schedule a DeferredUpdate, listeners use deferred
+			// delivery anyway.
+			$update->doUpdate();
+		}
+	}
+
+}