[Share 2.0] Add deleteFromSelf method

This allows recipient to delete a share. For user shares this is the
same as deleting (at least for now).
But for group shares this means creating a new share with type 2. With
permissions set to 0.

3 files changed, 104 insertions, 0 deletions

diff --git a/lib/private/share20/defaultshareprovider.php b/lib/private/share20/defaultshareprovider.php
index 5d768a4bc4b..8c193c437d3 100644
--- a/lib/private/share20/defaultshareprovider.php
+++ b/lib/private/share20/defaultshareprovider.php
@@ -21,6 +21,7 @@
 namespace OC\Share20;
 
 use OC\Share20\Exception\InvalidShare;
+use OC\Share20\Exception\ProviderException;
 use OC\Share20\Exception\ShareNotFound;
 use OC\Share20\Exception\BackendError;
 use OCP\Files\NotFoundException;
@@ -242,6 +243,84 @@ class DefaultShareProvider implements IShareProvider {
 	}
 
 	/**
+	 * Unshare a share from the recipient. If this is a group share
+	 * this means we need a special entry in the share db.
+	 *
+	 * @param IShare $share
+	 * @param IUser $recipient
+	 * @throws BackendError
+	 * @throws ProviderException
+	 */
+	public function deleteFromSelf(IShare $share, IUser $recipient) {
+		if ($share->getShareType() === \OCP\Share::SHARE_TYPE_GROUP) {
+
+			/** @var IGroup $group */
+			$group = $share->getSharedWith();
+
+			if (!$group->inGroup($recipient)) {
+				throw new ProviderException('Recipient not in receiving group');
+			}
+
+			// Try to fetch user specific share
+			$qb = $this->dbConn->getQueryBuilder();
+			$stmt = $qb->select('*')
+				->from('share')
+				->where($qb->expr()->eq('share_type', $qb->createNamedParameter(self::SHARE_TYPE_USERGROUP)))
+				->andWhere($qb->expr()->eq('share_with', $qb->createNamedParameter($recipient->getUID())))
+				->andWhere($qb->expr()->eq('parent', $qb->createNamedParameter($share->getId())))
+				->execute();
+
+			$data = $stmt->fetch();
+
+			/*
+			 * Check if there already is a user specific group share.
+			 * If there is update it (if required).
+			 */
+			if ($data === false) {
+				$qb = $this->dbConn->getQueryBuilder();
+
+				$type = $share->getPath() instanceof \OCP\Files\File ? 'file' : 'folder';
+
+				//Insert new share
+				$qb->insert('share')
+					->values([
+						'share_type' => $qb->createNamedParameter(self::SHARE_TYPE_USERGROUP),
+						'share_with' => $qb->createNamedParameter($recipient->getUID()),
+						'uid_owner' => $qb->createNamedParameter($share->getShareOwner()->getUID()),
+						'uid_initiator' => $qb->createNamedParameter($share->getSharedBy()->getUID()),
+						'parent' => $qb->createNamedParameter($share->getId()),
+						'item_type' => $qb->createNamedParameter($type),
+						'item_source' => $qb->createNamedParameter($share->getPath()->getId()),
+						'file_source' => $qb->createNamedParameter($share->getPath()->getId()),
+						'file_target' => $qb->createNamedParameter($share->getTarget()),
+						'permissions' => $qb->createNamedParameter(0),
+						'stime' => $qb->createNamedParameter($share->getSharetime()),
+					])->execute();
+
+			} else if ($data['permissions'] !== 0) {
+
+				// Update existing usergroup share
+				$qb = $this->dbConn->getQueryBuilder();
+				$qb->update('share')
+					->set('permissions', $qb->createNamedParameter(0))
+					->where($qb->expr()->eq('id', $qb->createNamedParameter($data['id'])))
+					->execute();
+			}
+
+		} else if ($share->getShareType() === \OCP\Share::SHARE_TYPE_USER) {
+
+			if ($share->getSharedWith() !== $recipient) {
+				throw new ProviderException('Recipient does not match');
+			}
+
+			// We can just delete user and link shares
+			$this->delete($share);
+		} else {
+			throw new ProviderException('Invalid shareType');
+		}
+	}
+
+	/**
 	 * Get all shares by the given user. Sharetype and path can be used to filter.
 	 *
 	 * @param IUser $user
diff --git a/lib/private/share20/ishareprovider.php b/lib/private/share20/ishareprovider.php
index 36d0f10c7f1..17ee4abb9a8 100644
--- a/lib/private/share20/ishareprovider.php
+++ b/lib/private/share20/ishareprovider.php
@@ -58,6 +58,15 @@ interface IShareProvider {
 	public function delete(IShare $share);
 
 	/**
+	 * Unshare a file from self as recipient.
+	 * This may require special handling.
+	 *
+	 * @param IShare $share
+	 * @param IUser $recipient
+	 */
+	public function deleteFromSelf(IShare $share, IUser $recipient);
+
+	/**
 	 * Get all shares by the given user
 	 *
 	 * @param IUser $user
diff --git a/lib/private/share20/manager.php b/lib/private/share20/manager.php
index 3935307b977..ea6463c745c 100644
--- a/lib/private/share20/manager.php
+++ b/lib/private/share20/manager.php
@@ -607,6 +607,22 @@ class Manager {
 
 
 	/**
+	 * Unshare a file as the recipient.
+	 * This can be different from a regular delete for example when one of
+	 * the users in a groups deletes that share. But the provider should
+	 * handle this.
+	 *
+	 * @param IShare $share
+	 * @param IUser $recipient
+	 */
+	public function deleteFromSelf(IShare $share, IUser $recipient) {
+		list($providerId, $id) = $this->splitFullId($share->getId());
+		$provider = $this->factory->getProvider($providerId);
+
+		$provider->deleteFromSelf($share, $recipient);
+	}
+
+	/**
 	 * Get shares shared by (initiated) by the provided user.
 	 *
 	 * @param IUser $user