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>

10 files changed, 218 insertions, 0 deletions

diff --git a/apps/federatedfilesharing/lib/FederatedShareProvider.php b/apps/federatedfilesharing/lib/FederatedShareProvider.php
index 5a12f8e9be3..f81b826f12c 100644
--- a/apps/federatedfilesharing/lib/FederatedShareProvider.php
+++ b/apps/federatedfilesharing/lib/FederatedShareProvider.php
@@ -38,6 +38,7 @@ use OCP\IConfig;
 use OCP\IL10N;
 use OCP\ILogger;
 use OCP\IUserManager;
+use OCP\Share\Exceptions\GenericShareException;
 use OCP\Share\IShare;
 use OCP\Share\IShareProvider;
 use OC\Share20\Exception\InvalidShare;
@@ -585,6 +586,10 @@ class FederatedShareProvider implements IShareProvider {
 		// TODO move this code over to this app
 	}
 
+	public function restore(IShare $share, string $recipient): IShare {
+		throw new GenericShareException('not implemented');
+	}
+
 
 	public function getSharesInFolder($userId, Folder $node, $reshares) {
 		$qb = $this->dbConnection->getQueryBuilder();
diff --git a/apps/files_sharing/appinfo/routes.php b/apps/files_sharing/appinfo/routes.php
index 8e5110c6a16..eea6715e57d 100644
--- a/apps/files_sharing/appinfo/routes.php
+++ b/apps/files_sharing/appinfo/routes.php
@@ -74,6 +74,19 @@ return [
 			'verb' => 'DELETE',
 		],
 		/*
+		 * Deleted Shares
+		 */
+		[
+			'name' => 'DeletedShareAPI#index',
+			'url'  => '/api/v1/deletedshares',
+			'verb' => 'GET',
+		],
+		[
+			'name' => 'DeletedShareAPI#undelete',
+			'url'  => '/api/v1/deletedshares/{id}',
+			'verb' => 'POST',
+		],
+		/*
 		 * OCS Sharee API
 		 */
 		[
diff --git a/apps/files_sharing/composer/composer/autoload_classmap.php b/apps/files_sharing/composer/composer/autoload_classmap.php
index e5a86bbd095..cb64d44a54d 100644
--- a/apps/files_sharing/composer/composer/autoload_classmap.php
+++ b/apps/files_sharing/composer/composer/autoload_classmap.php
@@ -22,6 +22,7 @@ return array(
     'OCA\\Files_Sharing\\Capabilities' => $baseDir . '/../lib/Capabilities.php',
     'OCA\\Files_Sharing\\Collaboration\\ShareRecipientSorter' => $baseDir . '/../lib/Collaboration/ShareRecipientSorter.php',
     'OCA\\Files_Sharing\\Command\\CleanupRemoteStorages' => $baseDir . '/../lib/Command/CleanupRemoteStorages.php',
+    'OCA\\Files_Sharing\\Controller\\DeletedShareAPIController' => $baseDir . '/../lib/Controller/DeletedShareAPIController.php',
     'OCA\\Files_Sharing\\Controller\\ExternalSharesController' => $baseDir . '/../lib/Controller/ExternalSharesController.php',
     'OCA\\Files_Sharing\\Controller\\PublicPreviewController' => $baseDir . '/../lib/Controller/PublicPreviewController.php',
     'OCA\\Files_Sharing\\Controller\\RemoteController' => $baseDir . '/../lib/Controller/RemoteController.php',
diff --git a/apps/files_sharing/composer/composer/autoload_static.php b/apps/files_sharing/composer/composer/autoload_static.php
index bf41ef45ea1..dcfd5c4fe4f 100644
--- a/apps/files_sharing/composer/composer/autoload_static.php
+++ b/apps/files_sharing/composer/composer/autoload_static.php
@@ -37,6 +37,7 @@ class ComposerStaticInitFiles_Sharing
         'OCA\\Files_Sharing\\Capabilities' => __DIR__ . '/..' . '/../lib/Capabilities.php',
         'OCA\\Files_Sharing\\Collaboration\\ShareRecipientSorter' => __DIR__ . '/..' . '/../lib/Collaboration/ShareRecipientSorter.php',
         'OCA\\Files_Sharing\\Command\\CleanupRemoteStorages' => __DIR__ . '/..' . '/../lib/Command/CleanupRemoteStorages.php',
+        'OCA\\Files_Sharing\\Controller\\DeletedShareAPIController' => __DIR__ . '/..' . '/../lib/Controller/DeletedShareAPIController.php',
         'OCA\\Files_Sharing\\Controller\\ExternalSharesController' => __DIR__ . '/..' . '/../lib/Controller/ExternalSharesController.php',
         'OCA\\Files_Sharing\\Controller\\PublicPreviewController' => __DIR__ . '/..' . '/../lib/Controller/PublicPreviewController.php',
         'OCA\\Files_Sharing\\Controller\\RemoteController' => __DIR__ . '/..' . '/../lib/Controller/RemoteController.php',
diff --git a/apps/files_sharing/lib/Controller/DeletedShareAPIController.php b/apps/files_sharing/lib/Controller/DeletedShareAPIController.php
new file mode 100644
index 00000000000..9dadf8e25b4
--- /dev/null
+++ b/apps/files_sharing/lib/Controller/DeletedShareAPIController.php
@@ -0,0 +1,119 @@
+<?php
+declare(strict_types=1);
+/**
+ * @Copyright 2018, Roeland Jago Douma <roeland@famdouma.nl>
+ * @Copyright 2018, John Molakvoæ (skjnldsv) <skjnldsv@protonmail.com>
+ *
+ * @author John Molakvoæ (skjnldsv) <skjnldsv@protonmail.com>
+ * @author Roeland Jago Douma <roeland@famdouma.nl>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Files_Sharing\Controller;
+
+use OCP\AppFramework\Http\DataResponse;
+use OCP\AppFramework\OCS\OCSException;
+use OCP\AppFramework\OCS\OCSNotFoundException;
+use OCP\AppFramework\OCSController;
+use OCP\IRequest;
+use OCP\IUserManager;
+use OCP\Share\Exceptions\GenericShareException;
+use OCP\Share\Exceptions\ShareNotFound;
+use OCP\Share\IManager as ShareManager;
+use OCP\Share\IShare;
+
+class DeletedShareAPIController extends OCSController {
+
+	/** @var ShareManager */
+	private $shareManager;
+
+	/** @var string */
+	private $userId;
+
+	/** @var IUserManager */
+	private $userManager;
+
+	public function __construct(string $appName,
+								IRequest $request,
+								ShareManager $shareManager,
+								string $UserId,
+								IUserManager $userManager) {
+		parent::__construct($appName, $request);
+
+		$this->shareManager = $shareManager;
+		$this->userId = $UserId;
+		$this->userManager = $userManager;
+	}
+
+	private function formatShare(IShare $share): array {
+		return [
+			'id' => $share->getFullId(),
+			'uid_owner' => $share->getShareOwner(),
+			'displayname_owner' => $this->userManager->get($share->getShareOwner())->getDisplayName(),
+			'path' => $share->getTarget(),
+		];
+	}
+
+	/**
+	 * @NoAdminRequired
+	 */
+	public function index(): DataResponse {
+		$shares = $this->shareManager->getSharedWith($this->userId, \OCP\Share::SHARE_TYPE_GROUP, null, -1, 0);
+
+		// Only get deleted shares
+		$shares = array_filter($shares, function(IShare $share) {
+			return $share->getPermissions() === 0;
+		});
+
+		// Only get shares where the owner still exists
+		$shares = array_filter($shares, function (IShare $share) {
+			return $this->userManager->userExists($share->getShareOwner());
+		});
+
+		$shares = array_map(function (IShare $share) {
+			return $this->formatShare($share);
+		}, $shares);
+
+		return new DataResponse($shares);
+	}
+
+	/**
+	 * @NoAdminRequired
+	 *
+	 * @throws OCSException
+	 */
+	public function undelete(string $id): DataResponse {
+		try {
+			$share = $this->shareManager->getShareById($id, $this->userId);
+		} catch (ShareNotFound $e) {
+			throw new OCSNotFoundException('Share not found');
+		}
+
+		if ($share->getPermissions() !== 0) {
+			throw new OCSNotFoundException('No deleted share found');
+		}
+
+		try {
+			$this->shareManager->restoreShare($share, $this->userId);
+		} catch (GenericShareException $e) {
+			throw new OCSException('Something went wrong');
+		}
+
+		return new DataResponse([]);
+	}
+}
diff --git a/apps/sharebymail/lib/ShareByMailProvider.php b/apps/sharebymail/lib/ShareByMailProvider.php
index 61b479d3e9b..1a1855b9c44 100644
--- a/apps/sharebymail/lib/ShareByMailProvider.php
+++ b/apps/sharebymail/lib/ShareByMailProvider.php
@@ -42,6 +42,7 @@ use OCP\Mail\IMailer;
 use OCP\Security\IHasher;
 use OCP\Security\ISecureRandom;
 use OC\Share20\Share;
+use OCP\Share\Exceptions\GenericShareException;
 use OCP\Share\Exceptions\ShareNotFound;
 use OCP\Share\IShare;
 use OCP\Share\IShareProvider;
@@ -692,6 +693,10 @@ class ShareByMailProvider implements IShareProvider {
 		// nothing to do here, mail shares are only outgoing shares
 	}
 
+	public function restore(IShare $share, string $recipient): IShare {
+		throw new GenericShareException('not implemented');
+	}
+
 	/**
 	 * @inheritdoc
 	 */
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