fix: preserve link shares on ownership transfer

Signed-off-by: Salvatore Martire <4652631+salmart-dev@users.noreply.github.com>

Author: salmart-dev

apps/files/lib/Service/OwnershipTransferService.php

@@ -18,6 +18,7 @@
 use OCA\Files\Exception\TransferOwnershipException;
 use OCA\Files_External\Config\ConfigAdapter;
 use OCA\GroupFolders\Mount\GroupMountPoint;
+use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\Encryption\IManager as IEncryptionManager;
 use OCP\Files\Config\IHomeMountProvider;
 use OCP\Files\Config\IUserMountCache;
@@ -27,6 +28,7 @@
 use OCP\Files\IRootFolder;
 use OCP\Files\Mount\IMountManager;
 use OCP\Files\NotFoundException;
+use OCP\IDBConnection;
 use OCP\IUser;
 use OCP\IUserManager;
 use OCP\L10N\IFactory;
@@ -53,6 +55,7 @@ public function __construct(
 		private IUserManager $userManager,
 		private IFactory $l10nFactory,
 		private IRootFolder $rootFolder,
+		private IDBConnection $connection,
 	) {
 	}
 
@@ -388,6 +391,9 @@ private function collectUsersShares(
 		}, $shares)));
 	}
 
+	/**
+	 * @return array<int, IShare> shares keyed by node ID
+	 */
 	private function collectIncomingShares(
 		string $sourceUid,
 		OutputInterface $output,
@@ -517,6 +523,8 @@ private function restoreShares(
 					if ($shareMountPoint) {
 						$this->mountManager->removeMount($shareMountPoint->getMountPoint());
 					}
+
+					$this->promoteLinkShares($share);
 					$this->shareManager->deleteShare($share);
 				} else {
 					if ($share->getShareOwner() === $sourceUid) {
@@ -565,6 +573,10 @@ private function restoreShares(
 		$output->writeln('');
 	}
 
+	/**
+	 * @param array<int, IShare> $sourceShares shares of the source user, keyed by node ID
+	 * @param array<int, IShare> $destinationShares shares of the destination user, keyed by node ID
+	 */
 	private function transferIncomingShares(string $sourceUid,
 		string $destinationUid,
 		array $sourceShares,
@@ -594,11 +606,13 @@ private function transferIncomingShares(string $sourceUid,
 				$shareTarget = $finalShareTarget . $shareTarget;
 				if ($share->getShareType() === IShare::TYPE_USER
 					&& $share->getSharedBy() === $destinationUid) {
+					$this->promoteLinkShares($share);
 					$this->shareManager->deleteShare($share);
 				} elseif (isset($destinationShares[$share->getNodeId()])) {
 					$destinationShare = $destinationShares[$share->getNodeId()];
 					// Keep the share which has the most permissions and discard the other one.
 					if ($destinationShare->getPermissions() < $share->getPermissions()) {
+						$this->promoteLinkShares($destinationShare, $share->getId());
 						$this->shareManager->deleteShare($destinationShare);
 						$share->setSharedWith($destinationUid);
 						// trigger refetching of the node so that the new owner and mountpoint are taken into account
@@ -615,8 +629,10 @@ private function transferIncomingShares(string $sourceUid,
 						$this->shareManager->moveShare($share, $destinationUid);
 						continue;
 					}
+					$this->promoteLinkShares($share, $destinationShare->getId());
 					$this->shareManager->deleteShare($share);
 				} elseif ($share->getShareOwner() === $destinationUid) {
+					$this->promoteLinkShares($share);
 					$this->shareManager->deleteShare($share);
 				} else {
 					$share->setSharedWith($destinationUid);
@@ -644,4 +660,19 @@ private function transferIncomingShares(string $sourceUid,
 		$progress->finish();
 		$output->writeln('');
 	}
+
+	/**
+	 * Sets the parent column of the link/email shares with $share as parent to
+	 * `null` or, if provided, to $newParentId.
+	 */
+	private function promoteLinkShares(IShare $share, ?string $newParentId = null): void {
+		$qb = $this->connection->getQueryBuilder();
+		$parentParam = $newParentId === null ? $qb->createNamedParameter(null, IQueryBuilder::PARAM_NULL) : $qb->createNamedParameter($newParentId, IQueryBuilder::PARAM_STR);
+
+		$qb->update('share')
+			->set('parent', $parentParam)
+			->where($qb->expr()->eq('parent', $qb->createNamedParameter($share->getId())))
+			->andWhere($qb->expr()->in('share_type', $qb->createNamedParameter([IShare::TYPE_LINK, IShare::TYPE_EMAIL], IQueryBuilder::PARAM_INT_ARRAY)))
+			->executeStatement();
+	}
 }