[WIP] Authoritative share mount provider

apps/files_sharing/composer/composer/autoload_classmap.php

@@ -69,6 +69,7 @@
     'OCA\\Files_Sharing\\Listener\\LoadPublicFileRequestAuthListener' => $baseDir . '/../lib/Listener/LoadPublicFileRequestAuthListener.php',
     'OCA\\Files_Sharing\\Listener\\LoadSidebarListener' => $baseDir . '/../lib/Listener/LoadSidebarListener.php',
     'OCA\\Files_Sharing\\Listener\\ShareInteractionListener' => $baseDir . '/../lib/Listener/ShareInteractionListener.php',
+    'OCA\\Files_Sharing\\Listener\\SharesUpdatedListener' => $baseDir . '/../lib/Listener/SharesUpdatedListener.php',
     'OCA\\Files_Sharing\\Listener\\UserAddedToGroupListener' => $baseDir . '/../lib/Listener/UserAddedToGroupListener.php',
     'OCA\\Files_Sharing\\Listener\\UserShareAcceptanceListener' => $baseDir . '/../lib/Listener/UserShareAcceptanceListener.php',
     'OCA\\Files_Sharing\\Middleware\\OCSShareAPIMiddleware' => $baseDir . '/../lib/Middleware/OCSShareAPIMiddleware.php',
@@ -94,6 +95,7 @@
     'OCA\\Files_Sharing\\Settings\\Personal' => $baseDir . '/../lib/Settings/Personal.php',
     'OCA\\Files_Sharing\\ShareBackend\\File' => $baseDir . '/../lib/ShareBackend/File.php',
     'OCA\\Files_Sharing\\ShareBackend\\Folder' => $baseDir . '/../lib/ShareBackend/Folder.php',
+    'OCA\\Files_Sharing\\ShareTargetValidator' => $baseDir . '/../lib/ShareTargetValidator.php',
     'OCA\\Files_Sharing\\SharedMount' => $baseDir . '/../lib/SharedMount.php',
     'OCA\\Files_Sharing\\SharedStorage' => $baseDir . '/../lib/SharedStorage.php',
     'OCA\\Files_Sharing\\SharesReminderJob' => $baseDir . '/../lib/SharesReminderJob.php',

apps/files_sharing/composer/composer/autoload_static.php

@@ -84,6 +84,7 @@ class ComposerStaticInitFiles_Sharing
         'OCA\\Files_Sharing\\Listener\\LoadPublicFileRequestAuthListener' => __DIR__ . '/..' . '/../lib/Listener/LoadPublicFileRequestAuthListener.php',
         'OCA\\Files_Sharing\\Listener\\LoadSidebarListener' => __DIR__ . '/..' . '/../lib/Listener/LoadSidebarListener.php',
         'OCA\\Files_Sharing\\Listener\\ShareInteractionListener' => __DIR__ . '/..' . '/../lib/Listener/ShareInteractionListener.php',
+        'OCA\\Files_Sharing\\Listener\\SharesUpdatedListener' => __DIR__ . '/..' . '/../lib/Listener/SharesUpdatedListener.php',
         'OCA\\Files_Sharing\\Listener\\UserAddedToGroupListener' => __DIR__ . '/..' . '/../lib/Listener/UserAddedToGroupListener.php',
         'OCA\\Files_Sharing\\Listener\\UserShareAcceptanceListener' => __DIR__ . '/..' . '/../lib/Listener/UserShareAcceptanceListener.php',
         'OCA\\Files_Sharing\\Middleware\\OCSShareAPIMiddleware' => __DIR__ . '/..' . '/../lib/Middleware/OCSShareAPIMiddleware.php',
@@ -109,6 +110,7 @@ class ComposerStaticInitFiles_Sharing
         'OCA\\Files_Sharing\\Settings\\Personal' => __DIR__ . '/..' . '/../lib/Settings/Personal.php',
         'OCA\\Files_Sharing\\ShareBackend\\File' => __DIR__ . '/..' . '/../lib/ShareBackend/File.php',
         'OCA\\Files_Sharing\\ShareBackend\\Folder' => __DIR__ . '/..' . '/../lib/ShareBackend/Folder.php',
+        'OCA\\Files_Sharing\\ShareTargetValidator' => __DIR__ . '/..' . '/../lib/ShareTargetValidator.php',
         'OCA\\Files_Sharing\\SharedMount' => __DIR__ . '/..' . '/../lib/SharedMount.php',
         'OCA\\Files_Sharing\\SharedStorage' => __DIR__ . '/..' . '/../lib/SharedStorage.php',
         'OCA\\Files_Sharing\\SharesReminderJob' => __DIR__ . '/..' . '/../lib/SharesReminderJob.php',

apps/files_sharing/lib/AppInfo/Application.php

@@ -24,6 +24,7 @@
 use OCA\Files_Sharing\Listener\LoadPublicFileRequestAuthListener;
 use OCA\Files_Sharing\Listener\LoadSidebarListener;
 use OCA\Files_Sharing\Listener\ShareInteractionListener;
+use OCA\Files_Sharing\Listener\SharesUpdatedListener;
 use OCA\Files_Sharing\Listener\UserAddedToGroupListener;
 use OCA\Files_Sharing\Listener\UserShareAcceptanceListener;
 use OCA\Files_Sharing\Middleware\OCSShareAPIMiddleware;
@@ -49,9 +50,11 @@
 use OCP\Group\Events\GroupChangedEvent;
 use OCP\Group\Events\GroupDeletedEvent;
 use OCP\Group\Events\UserAddedEvent;
+use OCP\Group\Events\UserRemovedEvent;
 use OCP\IDBConnection;
 use OCP\IGroup;
 use OCP\Share\Events\ShareCreatedEvent;
+use OCP\Share\Events\ShareDeletedEvent;
 use OCP\User\Events\UserChangedEvent;
 use OCP\User\Events\UserDeletedEvent;
 use OCP\Util;
@@ -109,6 +112,12 @@ function () use ($c) {
 		// File request auth
 		$context->registerEventListener(BeforeTemplateRenderedEvent::class, LoadPublicFileRequestAuthListener::class);
 
+		// Update mounts
+		$context->registerEventListener(ShareCreatedEvent::class, SharesUpdatedListener::class);
+		$context->registerEventListener(ShareDeletedEvent::class, SharesUpdatedListener::class);
+		$context->registerEventListener(UserAddedEvent::class, SharesUpdatedListener::class);
+		$context->registerEventListener(UserRemovedEvent::class, SharesUpdatedListener::class);
+
 		$context->registerConfigLexicon(ConfigLexicon::class);
 	}
 

apps/files_sharing/lib/Listener/SharesUpdatedListener.php

@@ -0,0 +1,71 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2025 Robin Appelman <[email protected]>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Files_Sharing\Listener;
+
+use OCA\Files_Sharing\MountProvider;
+use OCA\Files_Sharing\ShareTargetValidator;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+use OCP\Files\Config\IUserMountCache;
+use OCP\Files\Storage\IStorageFactory;
+use OCP\Group\Events\UserAddedEvent;
+use OCP\Group\Events\UserRemovedEvent;
+use OCP\IUser;
+use OCP\Share\Events\ShareCreatedEvent;
+use OCP\Share\Events\ShareDeletedEvent;
+use OCP\Share\IManager;
+
+/**
+ * Listen to various events that can change what shares a user has access to
+ *
+ * @template-implements IEventListener<UserAddedEvent|UserRemovedEvent|ShareCreatedEvent|ShareDeletedEvent>
+ */
+class SharesUpdatedListener implements IEventListener {
+	public function __construct(
+		private readonly IManager $shareManager,
+		private readonly IUserMountCache $userMountCache,
+		private readonly MountProvider $shareMountProvider,
+		private readonly IStorageFactory $storageFactory,
+		private readonly ShareTargetValidator $shareTargetValidator,
+	) {
+	}
+
+	public function handle(Event $event): void {
+		if ($event instanceof UserAddedEvent || $event instanceof UserRemovedEvent) {
+			$this->updateForUser($event->getUser());
+		}
+		if ($event instanceof ShareCreatedEvent || $event instanceof ShareDeletedEvent) {
+			foreach ($this->shareManager->getUsersForShare($event->getShare()) as $user) {
+				$this->updateForUser($user);
+			}
+		}
+	}
+
+	private function updateForUser(IUser $user): void {
+		$cachedMounts = $this->userMountCache->getMountsForUser($user);
+
+		$shares = $this->shareMountProvider->getSuperSharesForUser($user);
+
+		$foundUpdate = count($shares) !== count($cachedMounts);
+		foreach ($shares as &$share) {
+			[$parentShare, $groupedShares] = $share;
+			$mountPoint = '/' . $user->getUID() . '/files/' . $parentShare->getTarget();
+			$mountKey = $parentShare->getNodeId() . '::' . $mountPoint;
+			if (!isset($cachedMounts[$mountKey])) {
+				$foundUpdate = true;
+				$this->shareTargetValidator->verifyMountPoint($user, $parentShare, $cachedMounts, $groupedShares);
+			}
+		}
+
+		if ($foundUpdate) {
+			$mounts = $this->shareMountProvider->getMountsFromSuperShares($user, $shares, $this->storageFactory);
+			$this->userMountCache->registerMounts($user, $mounts, [MountProvider::class]);
+		}
+	}
+}

apps/files_sharing/lib/MountProvider.php

@@ -50,6 +50,14 @@ public function __construct(
 	 * @return IMountPoint[]
 	 */
 	public function getMountsForUser(IUser $user, IStorageFactory $loader) {
+		return $this->getMountsFromSuperShares($user, $this->getSuperSharesForUser($user), $loader);
+	}
+
+	/**
+	 * @param IUser $user
+	 * @return list<array{IShare, array<IShare>}> Tuple of [superShare, groupedShares]
+	 */
+	public function getSuperSharesForUser(IUser $user): array {
 		$userId = $user->getUID();
 		$shares = array_merge(
 			$this->shareManager->getSharedWith($userId, IShare::TYPE_USER, null, -1),
@@ -61,9 +69,7 @@ public function getMountsForUser(IUser $user, IStorageFactory $loader) {
 		);
 
 		$shares = $this->filterShares($shares, $userId);
-		$superShares = $this->buildSuperShares($shares, $user);
-
-		return $this->getMountsFromSuperShares($userId, $superShares, $loader, $user);
+		return $this->buildSuperShares($shares, $user);
 	}
 
 	/**
@@ -246,18 +252,18 @@ private function adjustTarget(
 	}
 	/**
 	 * @param string $userId
-	 * @param array $superShares
+	 * @param list<array{IShare, array<IShare>}> $superShares
 	 * @param IStorageFactory $loader
 	 * @param IUser $user
 	 * @return array
 	 * @throws Exception
 	 */
-	private function getMountsFromSuperShares(
-		string $userId,
+	public function getMountsFromSuperShares(
+		IUser $user,
 		array $superShares,
 		IStorageFactory $loader,
-		IUser $user,
 	): array {
+		$userId = $user->getUID();
 		$allMounts = $this->mountManager->getAll();
 		$mounts = [];
 		$view = new View('/' . $userId . '/files');
@@ -290,7 +296,6 @@ private function getMountsFromSuperShares(
 				$shareId = (int)$parentShare->getId();
 				$mount = new SharedMount(
 					'\OCA\Files_Sharing\SharedStorage',
-					$allMounts,
 					[
 						'user' => $userId,
 						// parent share
@@ -301,11 +306,8 @@ private function getMountsFromSuperShares(
 						'sharingDisabledForUser' => $sharingDisabledForUser
 					],
 					$loader,
-					$view,
-					$foldersExistCache,
 					$this->eventDispatcher,
 					$user,
-					$shareId <= $maxValidatedShare,
 				);
 
 				$newMaxValidatedShare = max($shareId, $newMaxValidatedShare);

apps/files_sharing/lib/ShareTargetValidator.php

@@ -0,0 +1,141 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * SPDX-FileCopyrightText: 2025 Robin Appelman <[email protected]>
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace OCA\Files_Sharing;
+
+use OC\Files\Filesystem;
+use OC\Files\SetupManager;
+use OC\Files\View;
+use OCP\Cache\CappedMemoryCache;
+use OCP\EventDispatcher\IEventDispatcher;
+use OCP\Files\Config\ICachedMountInfo;
+use OCP\Files\Mount\IMountManager;
+use OCP\Files\Mount\IMountPoint;
+use OCP\IUser;
+use OCP\Share\Events\VerifyMountPointEvent;
+use OCP\Share\IManager;
+use OCP\Share\IShare;
+
+/**
+ * Validate that mount target is valid
+ */
+class ShareTargetValidator {
+	private CappedMemoryCache $folderExistsCache;
+
+	public function __construct(
+		private readonly IManager $shareManager,
+		private readonly IEventDispatcher $eventDispatcher,
+		private readonly SetupManager $setupManager,
+		private readonly IMountManager $mountManager,
+	) {
+		$this->folderExistsCache = new CappedMemoryCache();
+	}
+
+	private function getViewForUser(IUser $user): View {
+		/**
+		 * @psalm-suppress InternalClass
+		 * @psalm-suppress InternalMethod
+		 */
+		return new View('/' . $user->getUID() . '/files');
+	}
+
+	/**
+	 * check if the parent folder exists otherwise move the mount point up
+	 *
+	 * @param ICachedMountInfo[] $allCachedMounts
+	 * @param IShare[] $childShares
+	 * @return string
+	 */
+	public function verifyMountPoint(
+		IUser $user,
+		IShare &$share,
+		array $allCachedMounts,
+		array $childShares,
+	): string {
+		$mountPoint = basename($share->getTarget());
+		$parent = dirname($share->getTarget());
+
+		$recipientView = $this->getViewForUser($user);
+		$event = new VerifyMountPointEvent($share, $recipientView, $parent);
+		$this->eventDispatcher->dispatchTyped($event);
+		$parent = $event->getParent();
+
+		/** @psalm-suppress InternalMethod */
+		$absoluteParent = $recipientView->getAbsolutePath($parent);
+		$this->setupManager->setupForPath($absoluteParent);
+		$parentMount = $this->mountManager->find($absoluteParent);
+
+		$cached = $this->folderExistsCache->get($parent);
+		if ($cached) {
+			$parentExists = $cached;
+		} else {
+			$parentCache = $parentMount->getStorage()->getCache();
+			$parentExists = $parentCache->inCache($parentMount->getInternalPath($absoluteParent));
+			$this->folderExistsCache->set($parent, $parentExists);
+		}
+		if (!$parentExists) {
+			$parent = Helper::getShareFolder($recipientView, $user->getUID());
+			/** @psalm-suppress InternalMethod */
+			$absoluteParent = $recipientView->getAbsolutePath($parent);
+		}
+
+		$newAbsoluteMountPoint = $this->generateUniqueTarget(
+			Filesystem::normalizePath($absoluteParent . '/' . $mountPoint),
+			$parentMount,
+			$allCachedMounts,
+		);
+
+		/** @psalm-suppress InternalMethod */
+		$newMountPoint = $recipientView->getRelativePath($newAbsoluteMountPoint);
+		if ($newMountPoint === null) {
+			return $share->getTarget();
+		}
+
+		if ($newMountPoint !== $share->getTarget()) {
+			$this->updateFileTarget($user, $newMountPoint, $share, $childShares);
+		}
+
+		return $newMountPoint;
+	}
+
+
+	/**
+	 * @param ICachedMountInfo[] $allCachedMounts
+	 */
+	private function generateUniqueTarget(string $absolutePath, IMountPoint $parentMount, array $allCachedMounts): string {
+		$pathInfo = pathinfo($absolutePath);
+		$ext = isset($pathInfo['extension']) ? '.' . $pathInfo['extension'] : '';
+		$name = $pathInfo['filename'];
+		$dir = $pathInfo['dirname'];
+
+		$i = 2;
+		$parentCache = $parentMount->getStorage()->getCache();
+		$internalPath = $parentMount->getInternalPath($absolutePath);
+		while ($parentCache->inCache($internalPath) || isset($allCachedMounts[$absolutePath . '/'])) {
+			$absolutePath = Filesystem::normalizePath($dir . '/' . $name . ' (' . $i . ')' . $ext);
+			$internalPath = $parentMount->getInternalPath($absolutePath);
+			$i++;
+		}
+
+		return $absolutePath;
+	}
+
+	/**
+	 * update fileTarget in the database if the mount point changed
+	 *
+	 * @param IShare[] $childShares
+	 */
+	private function updateFileTarget(IUser $user, string $newPath, IShare &$share, array $childShares) {
+		$share->setTarget($newPath);
+
+		foreach ($childShares as $tmpShare) {
+			$tmpShare->setTarget($newPath);
+			$this->shareManager->moveShare($tmpShare, $user->getUID());
+		}
+	}
+}