Add API to undelete delete group shares

When a group share is deleted we keep track of this in the DB.
Right now it is only possible for a recipient to get back the share by
asking the sharer to delete it and to share it again. This doesn't
scale.

This endpoint makes it possible to get back the share.

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>

4 files changed, 74 insertions, 0 deletions

diff --git a/lib/private/Share20/DefaultShareProvider.php b/lib/private/Share20/DefaultShareProvider.php
index 3c56b24707c..5e52156d1d0 100644
--- a/lib/private/Share20/DefaultShareProvider.php
+++ b/lib/private/Share20/DefaultShareProvider.php
@@ -31,6 +31,7 @@ namespace OC\Share20;
 
 use OC\Files\Cache\Cache;
 use OCP\Files\Folder;
+use OCP\Share\IShare;
 use OCP\Share\IShareProvider;
 use OC\Share20\Exception\InvalidShare;
 use OC\Share20\Exception\ProviderException;
@@ -412,6 +413,41 @@ class DefaultShareProvider implements IShareProvider {
 
 	/**
 	 * @inheritdoc
+	 *
+	 * For now this only works for group shares
+	 * If this gets implemented for normal shares we have to extend it
+	 */
+	public function restore(IShare $share, string $recipient): IShare {
+		$qb = $this->dbConn->getQueryBuilder();
+		$qb->select('permissions')
+			->from('share')
+			->where(
+				$qb->expr()->eq('id', $qb->createNamedParameter($share->getId()))
+			);
+		$cursor = $qb->execute();
+		$data = $cursor->fetch();
+		$cursor->closeCursor();
+
+		$originalPermission = $data['permissions'];
+
+		$qb = $this->dbConn->getQueryBuilder();
+		$qb->update('share')
+			->set('permissions', $qb->createNamedParameter($originalPermission))
+			->where(
+				$qb->expr()->eq('parent', $qb->createNamedParameter($share->getParent()))
+			)->andWhere(
+				$qb->expr()->eq('share_type', $qb->createNamedParameter(self::SHARE_TYPE_USERGROUP))
+			)->andWhere(
+				$qb->expr()->eq('share_with', $qb->createNamedParameter($recipient))
+			);
+
+		$qb->execute();
+
+		return $this->getShareById($share->getId(), $recipient);
+	}
+
+	/**
+	 * @inheritdoc
 	 */
 	public function move(\OCP\Share\IShare $share, $recipient) {
 		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER) {
@@ -922,6 +958,7 @@ class DefaultShareProvider implements IShareProvider {
 			while($data = $stmt->fetch()) {
 				$shareMap[$data['parent']]->setPermissions((int)$data['permissions']);
 				$shareMap[$data['parent']]->setTarget($data['file_target']);
+				$shareMap[$data['parent']]->setParent($data['parent']);
 			}
 
 			$stmt->closeCursor();
diff --git a/lib/private/Share20/Manager.php b/lib/private/Share20/Manager.php
index cddd8c8d92b..c0827f13732 100644
--- a/lib/private/Share20/Manager.php
+++ b/lib/private/Share20/Manager.php
@@ -61,6 +61,7 @@ use OCP\Share\Exceptions\GenericShareException;
 use OCP\Share\Exceptions\ShareNotFound;
 use OCP\Share\IManager;
 use OCP\Share\IProviderFactory;
+use OCP\Share\IShare;
 use Symfony\Component\EventDispatcher\EventDispatcher;
 use Symfony\Component\EventDispatcher\GenericEvent;
 use OCP\Share\IShareProvider;
@@ -978,6 +979,13 @@ class Manager implements IManager {
 		$this->eventDispatcher->dispatch('OCP\Share::postUnshareFromSelf', $event);
 	}
 
+	public function restoreShare(IShare $share, string $recipientId): IShare {
+		list($providerId, ) = $this->splitFullId($share->getFullId());
+		$provider = $this->factory->getProvider($providerId);
+
+		return $provider->restore($share, $recipientId);
+	}
+
 	/**
 	 * @inheritdoc
 	 */
diff --git a/lib/public/Share/IManager.php b/lib/public/Share/IManager.php
index 493db5e5149..56e35f517c1 100644
--- a/lib/public/Share/IManager.php
+++ b/lib/public/Share/IManager.php
@@ -29,6 +29,7 @@ namespace OCP\Share;
 use OCP\Files\Folder;
 use OCP\Files\Node;
 
+use OCP\Share\Exceptions\GenericShareException;
 use OCP\Share\Exceptions\ShareNotFound;
 
 /**
@@ -84,6 +85,20 @@ interface IManager {
 	public function deleteFromSelf(IShare $share, $recipientId);
 
 	/**
+	 * Restore the share when it has been deleted
+	 * Certain share types can be restored when they have been deleted
+	 * but the provider should properly handle this\
+	 *
+	 * @param IShare $share The share to restore
+	 * @param string $recipientId The user to restore the share for
+	 * @return IShare The restored share object
+	 * @throws GenericShareException In case restoring the share failed
+	 *
+	 * @since 14.0.0
+	 */
+	public function restoreShare(IShare $share, string $recipientId): IShare;
+
+	/**
 	 * Move the share as a recipient of the share.
 	 * This is updating the share target. So where the recipient has the share mounted.
 	 *
diff --git a/lib/public/Share/IShareProvider.php b/lib/public/Share/IShareProvider.php
index 4a1ac9b8b8d..6731bf8882b 100644
--- a/lib/public/Share/IShareProvider.php
+++ b/lib/public/Share/IShareProvider.php
@@ -25,6 +25,8 @@
 namespace OCP\Share;
 
 use OCP\Files\Folder;
+use OCP\Share\Exceptions\GenericShareException;
+use OCP\Share\Exceptions\ShareNotFound;
 use OCP\Files\Node;
 
 /**
@@ -81,6 +83,18 @@ interface IShareProvider {
 	public function deleteFromSelf(\OCP\Share\IShare $share, $recipient);
 
 	/**
+	 * Restore a share for a given recipient. The implementation could be provider independant.
+	 *
+	 * @param IShare $share
+	 * @param string $recipient
+	 * @return IShare The restored share object
+	 *
+	 * @since 14.0.0
+	 * @throws GenericShareException In case the share could not be restored
+	 */
+	public function restore(IShare $share, string $recipient): IShare;
+
+	/**
 	 * Move a share as a recipient.
 	 * This is updating the share target. Thus the mount point of the recipient.
 	 * This may require special handling. If a user moves a group share