fix(shares): Promote reshares into direct shares when share is deleted

Signed-off-by: Côme Chilliet <come.chilliet@nextcloud.com>

1 files changed, 14 insertions, 6 deletions

diff --git a/lib/private/Share20/Manager.php b/lib/private/Share20/Manager.php
index e5e5166b4a9..dfb270eb6e3 100644
--- a/lib/private/Share20/Manager.php
+++ b/lib/private/Share20/Manager.php
@@ -783,6 +783,7 @@ class Manager implements IManager {
 	 * @param IShare $share
 	 * @return IShare The share object
 	 * @throws \InvalidArgumentException
+	 * @throws GenericShareException
 	 */
 	public function updateShare(IShare $share) {
 		$expirationDateUpdated = false;
@@ -1040,7 +1041,8 @@ class Manager implements IManager {
 		return $deletedShares;
 	}
 
-	protected function deleteReshares(IShare $share): void {
+	/* Promote reshares into direct shares so that target user keeps access */
+	protected function promoteReshares(IShare $share): void {
 		try {
 			$node = $share->getNode();
 		} catch (NotFoundException) {
@@ -1058,7 +1060,7 @@ class Manager implements IManager {
 
 			foreach ($users as $user) {
 				/* Skip share owner */
-				if ($user->getUID() === $share->getShareOwner()) {
+				if ($user->getUID() === $share->getShareOwner() || $user->getUID() === $share->getSharedBy()) {
 					continue;
 				}
 				$userIds[] = $user->getUID();
@@ -1101,8 +1103,14 @@ class Manager implements IManager {
 			try {
 				$this->generalCreateChecks($child);
 			} catch (GenericShareException $e) {
-				$this->logger->debug('Delete reshare because of exception '.$e->getMessage(), ['exception' => $e]);
-				$this->deleteShare($child);
+				/* The check is invalid, promote it to a direct share from the sharer of parent share */
+				$this->logger->debug('Promote reshare because of exception ' . $e->getMessage(), ['exception' => $e, 'fullId' => $child->getFullId()]);
+				try {
+					$child->setSharedBy($share->getSharedBy());
+					$this->updateShare($child);
+				} catch (GenericShareException|\InvalidArgumentException $e) {
+					$this->logger->warning('Failed to promote reshare because of exception ' . $e->getMessage(), ['exception' => $e, 'fullId' => $child->getFullId()]);
+				}
 			}
 		}
 	}
@@ -1132,8 +1140,8 @@ class Manager implements IManager {
 
 		$this->dispatcher->dispatchTyped(new ShareDeletedEvent($share));
 
-		// Delete reshares of the deleted share
-		$this->deleteReshares($share);
+		// Promote reshares of the deleted share
+		$this->promoteReshares($share);
 	}