From 8af96afbff2edee36019727bfeaa061ce45b0f79 Mon Sep 17 00:00:00 2001
From: Louis Chemineau <louis@chmn.me>
Date: Thu, 20 Oct 2022 16:37:47 +0200
Subject: [PATCH] Listen to cache event for managing metadata

Signed-off-by: Louis Chemineau <louis@chmn.me>
---
 core/Application.php                       |  9 +--
 lib/private/Metadata/FileEventListener.php | 81 +++++++---------------
 2 files changed, 27 insertions(+), 63 deletions(-)

diff --git a/core/Application.php b/core/Application.php
index 749f2d176d440..41123fb3eeae4 100644
--- a/core/Application.php
+++ b/core/Application.php
@@ -52,9 +52,8 @@
 use OC\TagManager;
 use OCP\AppFramework\App;
 use OCP\EventDispatcher\IEventDispatcher;
-use OCP\Files\Events\Node\NodeDeletedEvent;
-use OCP\Files\Events\Node\NodeWrittenEvent;
-use OCP\Files\Events\NodeRemovedFromCache;
+use OCP\Files\Cache\NodeWrittenEvent;
+use OCP\Files\Cache\CacheEntryRemovedEvent;
 use OCP\IDBConnection;
 use OCP\User\Events\BeforeUserDeletedEvent;
 use OCP\User\Events\UserDeletedEvent;
@@ -327,9 +326,7 @@ function (GenericEvent $event) use ($container) {
 		$config = $container->get(IConfig::class);
 		if ($config->getSystemValueBool('enable_file_metadata', true)) {
 			/** @psalm-suppress InvalidArgument */
-			$eventDispatcher->addServiceListener(NodeDeletedEvent::class, FileEventListener::class);
-			/** @psalm-suppress InvalidArgument */
-			$eventDispatcher->addServiceListener(NodeRemovedFromCache::class, FileEventListener::class);
+			$eventDispatcher->addServiceListener(CacheEntryRemovedEvent::class, FileEventListener::class);
 			/** @psalm-suppress InvalidArgument */
 			$eventDispatcher->addServiceListener(NodeWrittenEvent::class, FileEventListener::class);
 		}
diff --git a/lib/private/Metadata/FileEventListener.php b/lib/private/Metadata/FileEventListener.php
index 162e85ff3aa9d..fe6e676cac522 100644
--- a/lib/private/Metadata/FileEventListener.php
+++ b/lib/private/Metadata/FileEventListener.php
@@ -21,89 +21,56 @@
 
 namespace OC\Metadata;
 
-use OC\Files\Filesystem;
 use OCP\EventDispatcher\Event;
 use OCP\EventDispatcher\IEventListener;
-use OCP\Files\Events\Node\NodeDeletedEvent;
+use OCP\Files\Cache\CacheEntryRemovedEvent;
 use OCP\Files\Events\Node\NodeWrittenEvent;
-use OCP\Files\Events\NodeRemovedFromCache;
 use OCP\Files\File;
-use OCP\Files\Node;
-use OCP\Files\NotFoundException;
-use OCP\Files\FileInfo;
-use Psr\Log\LoggerInterface;
 
 /**
- * @template-implements IEventListener<NodeRemovedFromCache>
- * @template-implements IEventListener<NodeDeletedEvent>
- * @template-implements IEventListener<NodeWrittenEvent>
+ * @template-implements IEventListener<CacheEntryRemovedEvent>
+ * @template-implements IEventListener<CacheEntryInsertedEvent>
  */
 class FileEventListener implements IEventListener {
 	private IMetadataManager $manager;
-	private LoggerInterface $logger;
 
-	public function __construct(IMetadataManager $manager, LoggerInterface $logger) {
+	public function __construct(
+		IMetadataManager $manager
+	) {
 		$this->manager = $manager;
-		$this->logger = $logger;
-	}
-
-	private function shouldExtractMetadata(Node $node): bool {
-		try {
-			if ($node->getMimetype() === 'httpd/unix-directory') {
-				return false;
-			}
-		} catch (NotFoundException $e) {
-			return false;
-		}
-		if ($node->getSize(false) <= 0) {
-			return false;
-		}
-
-		$path = $node->getPath();
-		return $this->isCorrectPath($path);
 	}
 
 	private function isCorrectPath(string $path): bool {
 		// TODO make this more dynamic, we have the same issue in other places
-		return !str_starts_with($path, 'appdata_') && !str_starts_with($path, 'files_versions/') && !str_starts_with($path, 'files_trashbin/');
+		return !str_starts_with($path, 'appdata_') && !str_starts_with($path, 'files_versions/');
 	}
 
+	/**
+	 * @param NodeWrittenEvent|CacheEntryRemovedEvent $event
+	 */
 	public function handle(Event $event): void {
-		if ($event instanceof NodeRemovedFromCache) {
-			if (!$this->isCorrectPath($event->getPath())) {
-				// Don't listen to paths for which we don't extract metadata
-				return;
-			}
-			$view = Filesystem::getView();
-			if (!$view) {
-				// Should not happen since a scan in the user folder should setup
-				// the file system.
-				$e = new \Exception(); // don't trigger, just get backtrace
-				$this->logger->error('Detecting deletion of a file with possible metadata but file system setup is not setup', [
-					'exception' => $e,
-					'app' => 'metadata'
-				]);
+		if ($event instanceof CacheEntryRemovedEvent) {
+			if ($event->getStorage()->is_dir($event->getPath())) {
 				return;
 			}
-			$info = $view->getFileInfo($event->getPath());
-			if ($info && $info->getType() === FileInfo::TYPE_FILE) {
-				$this->manager->clearMetadata($info->getId());
-			}
-		}
 
-		if ($event instanceof NodeDeletedEvent) {
-			$node = $event->getNode();
-			if ($this->shouldExtractMetadata($node)) {
-				/** @var File $node */
-				$this->manager->clearMetadata($event->getNode()->getId());
+			if ($this->isCorrectPath($event->getPath())) {
+				$this->manager->clearMetadata($event->getFileId());
 			}
 		}
 
 		if ($event instanceof NodeWrittenEvent) {
 			$node = $event->getNode();
-			if ($this->shouldExtractMetadata($node)) {
-				/** @var File $node */
-				$this->manager->generateMetadata($event->getNode(), false);
+			if ($node->getSize(false) <= 0) {
+				return;
+			}
+
+			if (!$this->isCorrectPath($node->getPath())) {
+				return;
+			}
+
+			if ($node instanceof File) {
+				$this->manager->generateMetadata($node, false);
 			}
 		}
 	}