Merge pull request #16498 from nextcloud/feature/noid/room_metadata

Allow calendar resources/rooms to provide metadata

12 files changed, 873 insertions, 1000 deletions

diff --git a/apps/dav/appinfo/info.xml b/apps/dav/appinfo/info.xml
index 2a11eacd9be..71b3699b1ec 100644
--- a/apps/dav/appinfo/info.xml
+++ b/apps/dav/appinfo/info.xml
@@ -5,7 +5,7 @@
 	<name>WebDAV</name>
 	<summary>WebDAV endpoint</summary>
 	<description>WebDAV endpoint</description>
-	<version>1.10.0</version>
+	<version>1.11.0</version>
 	<licence>agpl</licence>
 	<author>owncloud.org</author>
 	<namespace>DAV</namespace>
diff --git a/apps/dav/composer/composer/autoload_classmap.php b/apps/dav/composer/composer/autoload_classmap.php
index b550e37a31c..18b94dbf71f 100644
--- a/apps/dav/composer/composer/autoload_classmap.php
+++ b/apps/dav/composer/composer/autoload_classmap.php
@@ -179,6 +179,7 @@ return array(
     'OCA\\DAV\\Migration\\Version1008Date20181105110300' => $baseDir . '/../lib/Migration/Version1008Date20181105110300.php',
     'OCA\\DAV\\Migration\\Version1008Date20181105112049' => $baseDir . '/../lib/Migration/Version1008Date20181105112049.php',
     'OCA\\DAV\\Migration\\Version1008Date20181114084440' => $baseDir . '/../lib/Migration/Version1008Date20181114084440.php',
+    'OCA\\DAV\\Migration\\Version1011Date20190725113607' => $baseDir . '/../lib/Migration/Version1011Date20190725113607.php',
     'OCA\\DAV\\Provisioning\\Apple\\AppleProvisioningNode' => $baseDir . '/../lib/Provisioning/Apple/AppleProvisioningNode.php',
     'OCA\\DAV\\Provisioning\\Apple\\AppleProvisioningPlugin' => $baseDir . '/../lib/Provisioning/Apple/AppleProvisioningPlugin.php',
     'OCA\\DAV\\RootCollection' => $baseDir . '/../lib/RootCollection.php',
diff --git a/apps/dav/composer/composer/autoload_static.php b/apps/dav/composer/composer/autoload_static.php
index 736b77aa11a..4c45dc60e4f 100644
--- a/apps/dav/composer/composer/autoload_static.php
+++ b/apps/dav/composer/composer/autoload_static.php
@@ -194,6 +194,7 @@ class ComposerStaticInitDAV
         'OCA\\DAV\\Migration\\Version1008Date20181105110300' => __DIR__ . '/..' . '/../lib/Migration/Version1008Date20181105110300.php',
         'OCA\\DAV\\Migration\\Version1008Date20181105112049' => __DIR__ . '/..' . '/../lib/Migration/Version1008Date20181105112049.php',
         'OCA\\DAV\\Migration\\Version1008Date20181114084440' => __DIR__ . '/..' . '/../lib/Migration/Version1008Date20181114084440.php',
+        'OCA\\DAV\\Migration\\Version1011Date20190725113607' => __DIR__ . '/..' . '/../lib/Migration/Version1011Date20190725113607.php',
         'OCA\\DAV\\Provisioning\\Apple\\AppleProvisioningNode' => __DIR__ . '/..' . '/../lib/Provisioning/Apple/AppleProvisioningNode.php',
         'OCA\\DAV\\Provisioning\\Apple\\AppleProvisioningPlugin' => __DIR__ . '/..' . '/../lib/Provisioning/Apple/AppleProvisioningPlugin.php',
         'OCA\\DAV\\RootCollection' => __DIR__ . '/..' . '/../lib/RootCollection.php',
diff --git a/apps/dav/lib/BackgroundJob/UpdateCalendarResourcesRoomsBackgroundJob.php b/apps/dav/lib/BackgroundJob/UpdateCalendarResourcesRoomsBackgroundJob.php
index 3a9e3def05d..1327a095056 100644
--- a/apps/dav/lib/BackgroundJob/UpdateCalendarResourcesRoomsBackgroundJob.php
+++ b/apps/dav/lib/BackgroundJob/UpdateCalendarResourcesRoomsBackgroundJob.php
@@ -1,6 +1,6 @@
 <?php
 /**
- * @copyright 2018, Georg Ehrke <oc.list@georgehrke.com>
+ * @copyright 2019, Georg Ehrke <oc.list@georgehrke.com>
  *
  * @author Georg Ehrke <oc.list@georgehrke.com>
  *
@@ -26,6 +26,8 @@ namespace OCA\DAV\BackgroundJob;
 use OC\BackgroundJob\TimedJob;
 use OCA\DAV\CalDAV\CalDavBackend;
 use OCP\Calendar\BackendTemporarilyUnavailableException;
+use OCP\Calendar\IMetadataProvider;
+use OCP\Calendar\Resource\IBackend as IResourceBackend;
 use OCP\Calendar\Resource\IManager as IResourceManager;
 use OCP\Calendar\Resource\IResource;
 use OCP\Calendar\Room\IManager as IRoomManager;
@@ -41,23 +43,11 @@ class UpdateCalendarResourcesRoomsBackgroundJob extends TimedJob {
 	private $roomManager;
 
 	/** @var IDBConnection */
-	private $db;
+	private $dbConnection;
 
 	/** @var CalDavBackend */
 	private $calDavBackend;
 
-	/** @var string */
-	private $resourceDbTable;
-
-	/** @var string */
-	private $resourcePrincipalUri;
-
-	/** @var string */
-	private $roomDbTable;
-
-	/** @var string */
-	private $roomPrincipalUri;
-
 	/**
 	 * UpdateCalendarResourcesRoomsBackgroundJob constructor.
 	 *
@@ -66,16 +56,14 @@ class UpdateCalendarResourcesRoomsBackgroundJob extends TimedJob {
 	 * @param IDBConnection $dbConnection
 	 * @param CalDavBackend $calDavBackend
 	 */
-	public function __construct(IResourceManager $resourceManager, IRoomManager $roomManager,
-								IDBConnection $dbConnection, CalDavBackend $calDavBackend) {
+	public function __construct(IResourceManager $resourceManager,
+								IRoomManager $roomManager,
+								IDBConnection $dbConnection,
+								CalDavBackend $calDavBackend) {
 		$this->resourceManager = $resourceManager;
 		$this->roomManager = $roomManager;
-		$this->db = $dbConnection;
+		$this->dbConnection = $dbConnection;
 		$this->calDavBackend = $calDavBackend;
-		$this->resourceDbTable = 'calendar_resources';
-		$this->resourcePrincipalUri = 'principals/calendar-resources';
-		$this->roomDbTable = 'calendar_rooms';
-		$this->roomPrincipalUri = 'principals/calendar-rooms';
 
 		// run once an hour
 		$this->setInterval(60 * 60);
@@ -84,211 +72,132 @@ class UpdateCalendarResourcesRoomsBackgroundJob extends TimedJob {
 	/**
 	 * @param $argument
 	 */
-	public function run($argument) {
-		$this->runResources();
-		$this->runRooms();
+	public function run($argument):void {
+		$this->runForBackend(
+			$this->resourceManager,
+			'calendar_resources',
+			'calendar_resources_md',
+			'resource_id',
+			'principals/calendar-resources'
+		);
+		$this->runForBackend(
+			$this->roomManager,
+			'calendar_rooms',
+			'calendar_rooms_md',
+			'room_id',
+			'principals/calendar-rooms'
+		);
 	}
 
 	/**
-	 * run timed job for resources
+	 * Run background-job for one specific backendManager
+	 * either ResourceManager or RoomManager
+	 *
+	 * @param IResourceManager|IRoomManager $backendManager
+	 * @param string $dbTable
+	 * @param string $dbTableMetadata
+	 * @param string $foreignKey
+	 * @param string $principalPrefix
 	 */
-	private function runResources() {
-		$resourceBackends = $this->resourceManager->getBackends();
-		$cachedResources = $this->getCached($this->resourceDbTable);
-		$cachedResourceIds = $this->getCachedResourceIds($cachedResources);
+	private function runForBackend($backendManager,
+								   string $dbTable,
+								   string $dbTableMetadata,
+								   string $foreignKey,
+								   string $principalPrefix):void {
+		$backends = $backendManager->getBackends();
+
+		foreach($backends as $backend) {
+			$backendId = $backend->getBackendIdentifier();
 
-		$remoteResourceIds = [];
-		foreach($resourceBackends as $resourceBackend) {
 			try {
-				$remoteResourceIds[$resourceBackend->getBackendIdentifier()] =
-					$resourceBackend->listAllResources();
+				if ($backend instanceof IResourceBackend) {
+					$list = $backend->listAllResources();
+				} else {
+					$list = $backend->listAllRooms();
+				}
 			} catch(BackendTemporarilyUnavailableException $ex) {
-				// If the backend is temporarily unavailable
-				// ignore this backend in this execution
-				unset($cachedResourceIds[$resourceBackend->getBackendIdentifier()]);
+				continue;
 			}
-		}
-
-		$sortedResources = $this->sortByNewDeletedExisting($cachedResourceIds, $remoteResourceIds);
 
-		foreach($sortedResources['new'] as $backendId => $newResources) {
-			foreach ($newResources as $newResource) {
-				$backend = $this->resourceManager->getBackend($backendId);
-				if ($backend === null) {
+			$cachedList = $this->getAllCachedByBackend($dbTable, $backendId);
+			$newIds = array_diff($list, $cachedList);
+			$deletedIds = array_diff($cachedList, $list);
+			$editedIds = array_intersect($list, $cachedList);
+
+			foreach($newIds as $newId) {
+				try {
+					if ($backend instanceof IResourceBackend) {
+						$resource = $backend->getResource($newId);
+					} else {
+						$resource = $backend->getRoom($newId);
+					}
+
+					$metadata = [];
+					if ($resource instanceof IMetadataProvider) {
+						$metadata = $this->getAllMetadataOfBackend($resource);
+					}
+				} catch(BackendTemporarilyUnavailableException $ex) {
 					continue;
 				}
 
-				$resource = $backend->getResource($newResource);
-				$this->addToCache($this->resourceDbTable, $resource);
+				$id = $this->addToCache($dbTable, $backendId, $resource);
+				$this->addMetadataToCache($dbTableMetadata, $foreignKey, $id, $metadata);
+				// we don't create the calendar here, it is created lazily
+				// when an event is actually scheduled with this resource / room
 			}
-		}
-		foreach($sortedResources['deleted'] as $backendId => $deletedResources) {
-			foreach ($deletedResources as $deletedResource) {
-				$this->deleteFromCache($this->resourceDbTable,
-					$this->resourcePrincipalUri, $backendId, $deletedResource);
-			}
-		}
-		foreach($sortedResources['edited'] as $backendId => $editedResources) {
-			foreach ($editedResources as $editedResource) {
-				$backend = $this->resourceManager->getBackend($backendId);
-				if ($backend === null) {
-					continue;
-				}
 
-				$resource = $backend->getResource($editedResource);
-				$this->updateCache($this->resourceDbTable, $resource);
-			}
-		}
-	}
+			foreach($deletedIds as $deletedId) {
+				$id = $this->getIdForBackendAndResource($dbTable, $backendId, $deletedId);
+				$this->deleteFromCache($dbTable, $id);
+				$this->deleteMetadataFromCache($dbTableMetadata, $foreignKey, $id);
 
-	/**
-	 * run timed job for rooms
-	 */
-	private function runRooms() {
-		$roomBackends = $this->roomManager->getBackends();
-		$cachedRooms = $this->getCached($this->roomDbTable);
-		$cachedRoomIds = $this->getCachedRoomIds($cachedRooms);
-
-		$remoteRoomIds = [];
-		foreach($roomBackends as $roomBackend) {
-			try {
-				$remoteRoomIds[$roomBackend->getBackendIdentifier()] =
-					$roomBackend->listAllRooms();
-			} catch(BackendTemporarilyUnavailableException $ex) {
-				// If the backend is temporarily unavailable
-				// ignore this backend in this execution
-				unset($cachedRoomIds[$roomBackend->getBackendIdentifier()]);
+				$principalName = implode('-', [$backendId, $deletedId]);
+				$this->deleteCalendarDataForResource($principalPrefix, $principalName);
 			}
-		}
 
-		$sortedRooms = $this->sortByNewDeletedExisting($cachedRoomIds, $remoteRoomIds);
-
-		foreach($sortedRooms['new'] as $backendId => $newRooms) {
-			foreach ($newRooms as $newRoom) {
-				$backend = $this->roomManager->getBackend($backendId);
-				if ($backend === null) {
+			foreach($editedIds as $editedId) {
+				$id = $this->getIdForBackendAndResource($dbTable, $backendId, $editedId);
+
+				try {
+					if ($backend instanceof IResourceBackend) {
+						$resource = $backend->getResource($editedId);
+					} else {
+						$resource = $backend->getRoom($editedId);
+					}
+
+					$metadata = [];
+					if ($resource instanceof IMetadataProvider) {
+						$metadata = $this->getAllMetadataOfBackend($resource);
+					}
+				} catch(BackendTemporarilyUnavailableException $ex) {
 					continue;
 				}
 
-				$resource = $backend->getRoom($newRoom);
-				$this->addToCache($this->roomDbTable, $resource);
-			}
-		}
-		foreach($sortedRooms['deleted'] as $backendId => $deletedRooms) {
-			foreach ($deletedRooms as $deletedRoom) {
-				$this->deleteFromCache($this->roomDbTable,
-					$this->roomPrincipalUri, $backendId, $deletedRoom);
-			}
-		}
-		foreach($sortedRooms['edited'] as $backendId => $editedRooms) {
-			foreach ($editedRooms as $editedRoom) {
-				$backend = $this->roomManager->getBackend($backendId);
-				if ($backend === null) {
-					continue;
-				}
-
-				$resource = $backend->getRoom($editedRoom);
-				$this->updateCache($this->roomDbTable, $resource);
-			}
-		}
-	}
+				$this->updateCache($dbTable, $id, $resource);
 
-	/**
-	 * get cached db rows for resources / rooms
-	 * @param string $tableName
-	 * @return array
-	 */
-	private function getCached($tableName):array {
-		$query = $this->db->getQueryBuilder();
-		$query->select('*')->from($tableName);
-
-		$rows = [];
-		$stmt = $query->execute();
-		while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
-			$rows[] = $row;
-		}
-
-		return $rows;
-	}
-
-	/**
-	 * @param array $cachedResources
-	 * @return array
-	 */
-	private function getCachedResourceIds(array $cachedResources):array {
-		$cachedResourceIds = [];
-		foreach ($cachedResources as $cachedResource) {
-			if (!isset($cachedResourceIds[$cachedResource['backend_id']])) {
-				$cachedResourceIds[$cachedResource['backend_id']] = [];
-			}
-
-			$cachedResourceIds[$cachedResource['backend_id']][] =
-				$cachedResource['resource_id'];
-		}
-
-		return $cachedResourceIds;
-	}
-
-	/**
-	 * @param array $cachedRooms
-	 * @return array
-	 */
-	private function getCachedRoomIds(array $cachedRooms):array {
-		$cachedRoomIds = [];
-		foreach ($cachedRooms as $cachedRoom) {
-			if (!isset($cachedRoomIds[$cachedRoom['backend_id']])) {
-				$cachedRoomIds[$cachedRoom['backend_id']] = [];
-			}
-
-			$cachedRoomIds[$cachedRoom['backend_id']][] =
-				$cachedRoom['resource_id'];
-		}
-
-		return $cachedRoomIds;
-	}
-
-	/**
-	 * sort list of ids by whether they appear only in the backend /
-	 * only in the cache / in both
-	 *
-	 * @param array $cached
-	 * @param array $remote
-	 * @return array
-	 */
-	private function sortByNewDeletedExisting(array $cached, array $remote):array {
-		$sorted = [
-			'new' => [],
-			'deleted' => [],
-			'edited' => [],
-		];
-
-		$backendIds = array_merge(array_keys($cached), array_keys($remote));
-		foreach($backendIds as $backendId) {
-			if (!isset($cached[$backendId])) {
-				$sorted['new'][$backendId] = $remote[$backendId];
-			} elseif (!isset($remote[$backendId])) {
-				$sorted['deleted'][$backendId] = $cached[$backendId];
-			} else {
-				$sorted['new'][$backendId] = array_diff($remote[$backendId], $cached[$backendId]);
-				$sorted['deleted'][$backendId] = array_diff($cached[$backendId], $remote[$backendId]);
-				$sorted['edited'][$backendId] = array_intersect($remote[$backendId], $cached[$backendId]);
+				if ($resource instanceof IMetadataProvider) {
+					$cachedMetadata = $this->getAllMetadataOfCache($dbTableMetadata, $foreignKey, $id);
+					$this->updateMetadataCache($dbTableMetadata, $foreignKey, $id, $metadata, $cachedMetadata);
+				}
 			}
 		}
-
-		return $sorted;
 	}
 
 	/**
 	 * add entry to cache that exists remotely but not yet in cache
 	 *
 	 * @param string $table
+	 * @param string $backendId
 	 * @param IResource|IRoom $remote
+	 * @return int Insert id
 	 */
-	private function addToCache($table, $remote) {
-		$query = $this->db->getQueryBuilder();
+	private function addToCache(string $table,
+								string $backendId,
+								$remote):int {
+		$query = $this->dbConnection->getQueryBuilder();
 		$query->insert($table)
 			->values([
-				'backend_id' => $query->createNamedParameter($remote->getBackend()->getBackendIdentifier()),
+				'backend_id' => $query->createNamedParameter($backendId),
 				'resource_id' => $query->createNamedParameter($remote->getId()),
 				'email' => $query->createNamedParameter($remote->getEMail()),
 				'displayname' => $query->createNamedParameter($remote->getDisplayName()),
@@ -298,37 +207,70 @@ class UpdateCalendarResourcesRoomsBackgroundJob extends TimedJob {
 					))
 			])
 			->execute();
+		return $query->getLastInsertId();
+	}
+
+	/**
+	 * @param string $table
+	 * @param string $foreignKey
+	 * @param int $foreignId
+	 * @param array $metadata
+	 */
+	private function addMetadataToCache(string $table,
+										string $foreignKey,
+										int $foreignId,
+										array $metadata):void {
+		foreach($metadata as $key => $value) {
+			$query = $this->dbConnection->getQueryBuilder();
+			$query->insert($table)
+				->values([
+					$foreignKey => $query->createNamedParameter($foreignId),
+					'key' => $query->createNamedParameter($key),
+					'value' => $query->createNamedParameter($value),
+				])
+				->execute();
+		}
 	}
 
 	/**
 	 * delete entry from cache that does not exist anymore remotely
 	 *
 	 * @param string $table
-	 * @param string $principalUri
-	 * @param string $backendId
-	 * @param string $resourceId
+	 * @param int $id
 	 */
-	private function deleteFromCache($table, $principalUri, $backendId, $resourceId) {
-		$query = $this->db->getQueryBuilder();
+	private function deleteFromCache(string $table,
+									 int $id):void {
+		$query = $this->dbConnection->getQueryBuilder();
 		$query->delete($table)
-			->where($query->expr()->eq('backend_id', $query->createNamedParameter($backendId)))
-			->andWhere($query->expr()->eq('resource_id', $query->createNamedParameter($resourceId)))
+			->where($query->expr()->eq('id', $query->createNamedParameter($id)))
 			->execute();
+	}
 
-		$calendar = $this->calDavBackend->getCalendarByUri($principalUri, implode('-', [$backendId, $resourceId]));
-		if ($calendar !== null) {
-			$this->calDavBackend->deleteCalendar($calendar['id']);
-		}
+	/**
+	 * @param string $table
+	 * @param string $foreignKey
+	 * @param int $id
+	 */
+	private function deleteMetadataFromCache(string $table,
+											 string $foreignKey,
+											 int $id):void {
+		$query = $this->dbConnection->getQueryBuilder();
+		$query->delete($table)
+			->where($query->expr()->eq($foreignKey, $query->createNamedParameter($id)))
+			->execute();
 	}
 
 	/**
 	 * update an existing entry in cache
 	 *
 	 * @param string $table
+	 * @param int $id
 	 * @param IResource|IRoom $remote
 	 */
-	private function updateCache($table, $remote) {
-		$query = $this->db->getQueryBuilder();
+	private function updateCache(string $table,
+								 int $id,
+								 $remote):void {
+		$query = $this->dbConnection->getQueryBuilder();
 		$query->update($table)
 			->set('email', $query->createNamedParameter($remote->getEMail()))
 			->set('displayname', $query->createNamedParameter($remote->getDisplayName()))
@@ -336,12 +278,58 @@ class UpdateCalendarResourcesRoomsBackgroundJob extends TimedJob {
 				$this->serializeGroupRestrictions(
 					$remote->getGroupRestrictions()
 				)))
-			->where($query->expr()->eq('backend_id', $query->createNamedParameter($remote->getBackend()->getBackendIdentifier())))
-			->andWhere($query->expr()->eq('resource_id', $query->createNamedParameter($remote->getId())))
+			->where($query->expr()->eq('id', $query->createNamedParameter($id)))
 			->execute();
 	}
 
 	/**
+	 * @param string $dbTable
+	 * @param string $foreignKey
+	 * @param int $id
+	 * @param array $metadata
+	 * @param array $cachedMetadata
+	 */
+	private function updateMetadataCache(string $dbTable,
+										 string $foreignKey,
+										 int $id,
+										 array $metadata,
+										 array $cachedMetadata):void {
+		$newMetadata = array_diff_key($metadata, $cachedMetadata);
+		$deletedMetadata = array_diff_key($cachedMetadata, $metadata);
+
+		foreach ($newMetadata as $key => $value) {
+			$query = $this->dbConnection->getQueryBuilder();
+			$query->insert($dbTable)
+				->values([
+					$foreignKey => $query->createNamedParameter($id),
+					'key' => $query->createNamedParameter($key),
+					'value' => $query->createNamedParameter($value),
+				])
+				->execute();
+		}
+
+		foreach($deletedMetadata as $key => $value) {
+			$query = $this->dbConnection->getQueryBuilder();
+			$query->delete($dbTable)
+				->where($query->expr()->eq($foreignKey, $query->createNamedParameter($id)))
+				->andWhere($query->expr()->eq('key', $query->createNamedParameter($key)))
+				->execute();
+		}
+
+		$existingKeys = array_keys(array_intersect_key($metadata, $cachedMetadata));
+		foreach($existingKeys as $existingKey) {
+			if ($metadata[$existingKey] !== $cachedMetadata[$existingKey]) {
+				$query = $this->dbConnection->getQueryBuilder();
+				$query->update($dbTable)
+					->set('value', $query->createNamedParameter($metadata[$existingKey]))
+					->where($query->expr()->eq($foreignKey, $query->createNamedParameter($id)))
+					->andWhere($query->expr()->eq('key', $query->createNamedParameter($existingKey)))
+					->execute();
+			}
+		}
+	}
+
+	/**
 	 * serialize array of group restrictions to store them in database
 	 *
 	 * @param array $groups
@@ -350,4 +338,102 @@ class UpdateCalendarResourcesRoomsBackgroundJob extends TimedJob {
 	private function serializeGroupRestrictions(array $groups):string {
 		return \json_encode($groups);
 	}
+
+	/**
+	 * Gets all metadata of a backend
+	 *
+	 * @param IResource|IRoom $resource
+	 * @return array
+	 */
+	private function getAllMetadataOfBackend($resource):array {
+		if (!($resource instanceof IMetadataProvider)) {
+			return [];
+		}
+
+		$keys = $resource->getAllAvailableMetadataKeys();
+		$metadata = [];
+		foreach($keys as $key) {
+			$metadata[$key] = $resource->getMetadataForKey($key);
+		}
+
+		return $metadata;
+	}
+
+	/**
+	 * @param string $table
+	 * @param string $foreignKey
+	 * @param int $id
+	 * @return array
+	 */
+	private function getAllMetadataOfCache(string $table,
+										   string $foreignKey,
+										   int $id):array {
+		$query = $this->dbConnection->getQueryBuilder();
+		$query->select(['key', 'value'])
+			->from($table)
+			->where($query->expr()->eq($foreignKey, $query->createNamedParameter($id)));
+		$stmt = $query->execute();
+		$rows = $stmt->fetchAll(\PDO::FETCH_ASSOC);
+
+		$metadata = [];
+		foreach($rows as $row) {
+			$metadata[$row['key']] = $row['value'];
+		}
+
+		return $metadata;
+	}
+
+	/**
+	 * Gets all cached rooms / resources by backend
+	 *
+	 * @param $tableName
+	 * @param $backendId
+	 * @return array
+	 */
+	private function getAllCachedByBackend(string $tableName,
+										   string $backendId):array {
+		$query = $this->dbConnection->getQueryBuilder();
+		$query->select('resource_id')
+			->from($tableName)
+			->where($query->expr()->eq('backend_id', $query->createNamedParameter($backendId)));
+		$stmt = $query->execute();
+
+		return array_map(function($row) {
+			return $row['resource_id'];
+		}, $stmt->fetchAll(\PDO::FETCH_NAMED));
+	}
+
+	/**
+	 * @param $principalPrefix
+	 * @param $principalUri
+	 */
+	private function deleteCalendarDataForResource(string $principalPrefix,
+												   string $principalUri):void {
+		$calendar = $this->calDavBackend->getCalendarByUri(
+			implode('/', [$principalPrefix, $principalUri]),
+			CalDavBackend::RESOURCE_BOOKING_CALENDAR_URI);
+
+		if ($calendar !== null) {
+			$this->calDavBackend->deleteCalendar($calendar['id']);
+		}
+	}
+
+	/**
+	 * @param $table
+	 * @param $backendId
+	 * @param $resourceId
+	 * @return int
+	 */
+	private function getIdForBackendAndResource(string $table,
+												string $backendId,
+												string $resourceId):int {
+		$query = $this->dbConnection->getQueryBuilder();
+		$query->select('id')
+			->from($table)
+			->where($query->expr()->eq('backend_id', $query->createNamedParameter($backendId)))
+			->andWhere($query->expr()->eq('resource_id', $query->createNamedParameter($resourceId)));
+		$stmt = $query->execute();
+
+		return $stmt->fetch(\PDO::FETCH_NAMED)['id'];
+	}
 }
diff --git a/apps/dav/lib/CalDAV/ResourceBooking/AbstractPrincipalBackend.php b/apps/dav/lib/CalDAV/ResourceBooking/AbstractPrincipalBackend.php
index 90d147f6741..aab5fcab8ad 100644
--- a/apps/dav/lib/CalDAV/ResourceBooking/AbstractPrincipalBackend.php
+++ b/apps/dav/lib/CalDAV/ResourceBooking/AbstractPrincipalBackend.php
@@ -1,6 +1,6 @@
 <?php
 /**
- * @copyright 2018, Georg Ehrke <oc.list@georgehrke.com>
+ * @copyright 2019, Georg Ehrke <oc.list@georgehrke.com>
  *
  * @author Georg Ehrke <oc.list@georgehrke.com>
  *
@@ -51,6 +51,12 @@ abstract class AbstractPrincipalBackend implements BackendInterface {
 	private $dbTableName;
 
 	/** @var string */
+	private $dbMetaDataTableName;
+
+	/** @var string */
+	private $dbForeignKeyName;
+
+	/** @var string */
 	private $cuType;
 
 	/**
@@ -74,7 +80,9 @@ abstract class AbstractPrincipalBackend implements BackendInterface {
 		$this->groupManager = $groupManager;
 		$this->logger = $logger;
 		$this->principalPrefix = $principalPrefix;
-		$this->dbTableName = 'calendar_' . $dbPrefix;
+		$this->dbTableName = 'calendar_' . $dbPrefix . 's';
+		$this->dbMetaDataTableName = $this->dbTableName . '_md';
+		$this->dbForeignKeyName = $dbPrefix . '_id';
 		$this->cuType = $cuType;
 	}
 
@@ -100,8 +108,31 @@ abstract class AbstractPrincipalBackend implements BackendInterface {
 				->from($this->dbTableName);
 			$stmt = $query->execute();
 
+			$metaDataQuery = $this->db->getQueryBuilder();
+			$metaDataQuery->select([$this->dbForeignKeyName, 'key', 'value'])
+				->from($this->dbMetaDataTableName);
+			$metaDataStmt = $metaDataQuery->execute();
+			$metaDataRows = $metaDataStmt->fetchAll(\PDO::FETCH_ASSOC);
+
+			$metaDataById = [];
+			foreach($metaDataRows as $metaDataRow) {
+				if (!isset($metaDataById[$metaDataRow[$this->dbForeignKeyName]])) {
+					$metaDataById[$metaDataRow[$this->dbForeignKeyName]] = [];
+				}
+
+				$metaDataById[$metaDataRow[$this->dbForeignKeyName]][$metaDataRow['key']] =
+					$metaDataRow['value'];
+			}
+
 			while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
-				$principals[] = $this->rowToPrincipal($row);
+				$id = $row['id'];
+
+				if (isset($metaDataById[$id])) {
+					$principals[] = $this->rowToPrincipal($row, $metaDataById[$id]);
+				} else {
+					$principals[] = $this->rowToPrincipal($row);
+				}
+
 			}
 
 			$stmt->closeCursor();
@@ -138,7 +169,50 @@ abstract class AbstractPrincipalBackend implements BackendInterface {
 			return null;
 		}
 
-		return $this->rowToPrincipal($row);
+		$metaDataQuery = $this->db->getQueryBuilder();
+		$metaDataQuery->select(['key', 'value'])
+			->from($this->dbMetaDataTableName)
+			->where($metaDataQuery->expr()->eq($this->dbForeignKeyName, $metaDataQuery->createNamedParameter($row['id'])));
+		$metaDataStmt = $metaDataQuery->execute();
+		$metaDataRows = $metaDataStmt->fetchAll(\PDO::FETCH_ASSOC);
+		$metadata = [];
+
+		foreach($metaDataRows as $metaDataRow) {
+			$metadata[$metaDataRow['key']] = $metaDataRow['value'];
+		}
+
+		return $this->rowToPrincipal($row, $metadata);
+	}
+
+	/**
+	 * @param int $id
+	 * @return array|null
+	 */
+	public function getPrincipalById($id):?array {
+		$query = $this->db->getQueryBuilder();
+		$query->select(['id', 'backend_id', 'resource_id', 'email', 'displayname'])
+			->from($this->dbTableName)
+			->where($query->expr()->eq('id', $query->createNamedParameter($id)));
+		$stmt = $query->execute();
+		$row = $stmt->fetch(\PDO::FETCH_ASSOC);
+
+		if(!$row) {
+			return null;
+		}
+
+		$metaDataQuery = $this->db->getQueryBuilder();
+		$metaDataQuery->select(['key', 'value'])
+			->from($this->dbMetaDataTableName)
+			->where($metaDataQuery->expr()->eq($this->dbForeignKeyName, $metaDataQuery->createNamedParameter($row['id'])));
+		$metaDataStmt = $metaDataQuery->execute();
+		$metaDataRows = $metaDataStmt->fetchAll(\PDO::FETCH_ASSOC);
+		$metadata = [];
+
+		foreach($metaDataRows as $metaDataRow) {
+			$metadata[$metaDataRow['key']] = $metaDataRow['value'];
+		}
+
+		return $this->rowToPrincipal($row, $metadata);
 	}
 
 	/**
@@ -253,7 +327,15 @@ abstract class AbstractPrincipalBackend implements BackendInterface {
 					break;
 
 				default:
-					$results[] = [];
+					$rowsByMetadata = $this->searchPrincipalsByMetadataKey($prop, $value);
+					$filteredRows = array_filter($rowsByMetadata, function($row) use ($usersGroups) {
+						return $this->isAllowedToAccessResource($row, $usersGroups);
+					});
+
+					$results[] = array_map(function($row) {
+						return $row['uri'];
+					}, $filteredRows);
+
 					break;
 			}
 		}
@@ -275,6 +357,39 @@ abstract class AbstractPrincipalBackend implements BackendInterface {
 	}
 
 	/**
+	 * Searches principals based on their metadata keys.
+	 * This allows to search for all principals with a specific key.
+	 * e.g.:
+	 * '{http://nextcloud.com/ns}room-building-address' => 'ABC Street 123, ...'
+	 *
+	 * @param $key
+	 * @param $value
+	 * @return array
+	 */
+	private function searchPrincipalsByMetadataKey($key, $value):array {
+		$query = $this->db->getQueryBuilder();
+		$query->select([$this->dbForeignKeyName])
+			->from($this->dbMetaDataTableName)
+			->where($query->expr()->eq('key', $query->createNamedParameter($key)))
+			->andWhere($query->expr()->iLike('value', $query->createNamedParameter('%' . $this->db->escapeLikeParameter($value) . '%')));
+		$stmt = $query->execute();
+
+		$rows = [];
+		while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+			$id = $row[$this->dbForeignKeyName];
+
+			$principalRow = $this->getPrincipalById($id);
+			if (!$principalRow) {
+				continue;
+			}
+
+			$rows[] = $principalRow;
+		}
+
+		return $rows;
+	}
+
+	/**
 	 * @param string $uri
 	 * @param string $principalPrefix
 	 * @return null|string
@@ -338,14 +453,18 @@ abstract class AbstractPrincipalBackend implements BackendInterface {
 
 	/**
 	 * convert database row to principal
+	 *
+	 * @param String[] $row
+	 * @param String[] $metadata
+	 * @return Array
 	 */
-	private function rowToPrincipal($row) {
-		return [
+	private function rowToPrincipal(array $row, array $metadata=[]):array {
+		return array_merge([
 			'uri' => $this->principalPrefix . '/' . $row['backend_id'] . '-' . $row['resource_id'],
 			'{DAV:}displayname' => $row['displayname'],
 			'{http://sabredav.org/ns}email-address' => $row['email'],
 			'{urn:ietf:params:xml:ns:caldav}calendar-user-type' => $this->cuType,
-		];
+		], $metadata);
 	}
 
 	/**
@@ -353,7 +472,7 @@ abstract class AbstractPrincipalBackend implements BackendInterface {
 	 * @param $userGroups
 	 * @return bool
 	 */
-	private function isAllowedToAccessResource($row, $userGroups) {
+	private function isAllowedToAccessResource(array $row, array $userGroups):bool {
 		if (!isset($row['group_restrictions']) ||
 			$row['group_restrictions'] === null ||
 			$row['group_restrictions'] === '') {
diff --git a/apps/dav/lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php b/apps/dav/lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php
index f8f10e78f94..0f6e6e7b4fd 100644
--- a/apps/dav/lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php
+++ b/apps/dav/lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php
@@ -40,6 +40,6 @@ class ResourcePrincipalBackend extends AbstractPrincipalBackend {
 								IGroupManager $groupManager,
 								ILogger $logger) {
 		parent::__construct($dbConnection, $userSession, $groupManager, $logger,
-			'principals/calendar-resources', 'resources', 'RESOURCE');
+			'principals/calendar-resources', 'resource', 'RESOURCE');
 	}
 }
diff --git a/apps/dav/lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php b/apps/dav/lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php
index 3059ed80ea6..68a344aa0ca 100644
--- a/apps/dav/lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php
+++ b/apps/dav/lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php
@@ -40,6 +40,6 @@ class RoomPrincipalBackend extends AbstractPrincipalBackend {
 								IGroupManager $groupManager,
 								ILogger $logger) {
 		parent::__construct($dbConnection, $userSession, $groupManager, $logger,
-			'principals/calendar-rooms', 'rooms', 'ROOM');
+			'principals/calendar-rooms', 'room', 'ROOM');
 	}
 }
diff --git a/apps/dav/lib/Migration/Version1011Date20190725113607.php b/apps/dav/lib/Migration/Version1011Date20190725113607.php
new file mode 100644
index 00000000000..ac4019e64e6
--- /dev/null
+++ b/apps/dav/lib/Migration/Version1011Date20190725113607.php
@@ -0,0 +1,69 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OCA\DAV\Migration;
+
+use Closure;
+use Doctrine\DBAL\Types\Type;
+use OCP\DB\ISchemaWrapper;
+use OCP\Migration\SimpleMigrationStep;
+use OCP\Migration\IOutput;
+
+/**
+ * Auto-generated migration step: Please modify to your needs!
+ */
+class Version1011Date20190725113607 extends SimpleMigrationStep {
+
+	/**
+	 * @param IOutput $output
+	 * @param \Closure $schemaClosure The `\Closure` returns a `ISchemaWrapper`
+	 * @param array $options
+	 * @return null|ISchemaWrapper
+	 * @since 13.0.0
+	 */
+	public function changeSchema(IOutput $output, \Closure $schemaClosure, array $options) {
+		/** @var ISchemaWrapper $schema */
+		$schema = $schemaClosure();
+
+		$types = ['resource', 'room'];
+		foreach($types as $type) {
+			if (!$schema->hasTable($this->getMetadataTableName($type))) {
+				$table = $schema->createTable($this->getMetadataTableName($type));
+
+				$table->addColumn('id', Type::BIGINT, [
+					'autoincrement' => true,
+					'notnull' => true,
+					'length' => 11,
+					'unsigned' => true,
+				]);
+				$table->addColumn($type . '_id', Type::BIGINT, [
+					'notnull' => true,
+					'length' => 11,
+					'unsigned' => true,
+				]);
+				$table->addColumn('key', Type::STRING, [
+					'notnull' => true,
+					'length' => 255,
+				]);
+				$table->addColumn('value', Type::STRING, [
+					'notnull' => false,
+					'length' => 4000,
+				]);
+
+				$table->setPrimaryKey(['id']);
+				$table->addIndex([$type . '_id', 'key'], $this->getMetadataTableName($type) . '_idk');
+			}
+		}
+
+		return $schema;
+	}
+
+	/**
+	 * @param string $type
+	 * @return string
+	 */
+	private function getMetadataTableName(string $type):string {
+		return 'calendar_' . $type . 's_md';
+	}
+}
diff --git a/apps/dav/tests/unit/BackgroundJob/UpdateCalendarResourcesRoomsBackgroundJobTest.php b/apps/dav/tests/unit/BackgroundJob/UpdateCalendarResourcesRoomsBackgroundJobTest.php
index e012d5e3f18..e451570b73f 100644
--- a/apps/dav/tests/unit/BackgroundJob/UpdateCalendarResourcesRoomsBackgroundJobTest.php
+++ b/apps/dav/tests/unit/BackgroundJob/UpdateCalendarResourcesRoomsBackgroundJobTest.php
@@ -26,6 +26,7 @@ use OCA\DAV\BackgroundJob\UpdateCalendarResourcesRoomsBackgroundJob;
 
 use OCA\DAV\CalDAV\CalDavBackend;
 use OCP\Calendar\BackendTemporarilyUnavailableException;
+use OCP\Calendar\IMetadataProvider;
 use OCP\Calendar\Resource\IBackend;
 use OCP\Calendar\Resource\IManager as IResourceManager;
 use OCP\Calendar\Resource\IResource;
@@ -61,34 +62,38 @@ class UpdateCalendarResourcesRoomsBackgroundJobTest extends TestCase {
 	protected function tearDown() {
 		$query = self::$realDatabase->getQueryBuilder();
 		$query->delete('calendar_resources')->execute();
+		$query->delete('calendar_resources_md')->execute();
 		$query->delete('calendar_rooms')->execute();
+		$query->delete('calendar_rooms_md')->execute();
 	}
 
 	/**
 	 * Data in Cache:
 	 * resources:
-	 *  [backend1, res1, Beamer1, {}]
-	 *  [backend1, res2, TV1, {}]
-	 *  [backend2, res3, Beamer2, {}]
-	 *  [backend2, res4, TV2, {}]
-	 *  [backend3, res5, Beamer3, {}]
-	 *  [backend3, res6, Pointer, {foo, bar}]
+	 *  [backend1, res1, Beamer1, {}] - []
+	 *  [backend1, res2, TV1, {}] - []
+	 *  [backend2, res3, Beamer2, {}] - ['meta1' => 'value1', 'meta2' => 'value2']
+	 *  [backend2, res4, TV2, {}] - ['meta1' => 'value1', 'meta3' => 'value3-old']
+	 *  [backend3, res5, Beamer3, {}] - []
+	 *  [backend3, res6, Pointer, {foo, bar}] - ['meta99' => 'value99']
 	 *
 	 * Data in Backend:
 	 *  backend1 gone
 	 *  backend2 throws BackendTemporarilyUnavailableException
-	 *  [backend3, res6, Pointer123, {foo, biz}]
-	 *  [backend3, res7, Resource4, {biz}]
-	 *  [backend4, res8, Beamer, {}]
-	 *  [backend4, res9, Beamer2, {}]
+	 *  [backend3, res6, Pointer123, {foo, biz}] - ['meta99' => 'value99-new', 'meta123' => 'meta456']
+	 *  [backend3, res7, Resource4, {biz}] - ['meta1' => 'value1']
+	 *  [backend4, res8, Beamer, {}] - ['meta2' => 'value2']
+	 *  [backend4, res9, Beamer2, {}] - []
 	 *
 	 * Expected after run:
-	 *  [backend2, res3, Beamer2, {}]
-	 *  [backend2, res4, TV2, {}]
-	 *  [backend3, res6, Pointer123, {foo, biz}]
-	 *  [backend3, res7, Resource4, {biz}]
-	 *  [backend4, res8, Beamer, {}]
-	 *  [backend4, res9, Beamer2, {}]
+	 * 	[backend1, res1, Beamer1, {}] - []
+	 *  [backend1, res2, TV1, {}] - []
+	 *  [backend2, res3, Beamer2, {}] - ['meta1' => 'value1', 'meta2' => 'value2']
+	 *  [backend2, res4, TV2, {}] - ['meta1' => 'value1', 'meta3' => 'value3-old']
+	 *  [backend3, res6, Pointer123, {foo, biz}]  - ['meta99' => 'value99-new', 'meta123' => 'meta456']
+	 *  [backend3, res7, Resource4, {biz}] - ['meta1' => 'value1']
+	 *  [backend4, res8, Beamer, {}] - ['meta2' => 'value2']
+	 *  [backend4, res9, Beamer2, {}] - []
 	 */
 
 	public function testRun() {
@@ -98,9 +103,9 @@ class UpdateCalendarResourcesRoomsBackgroundJobTest extends TestCase {
 		$backend3 = $this->createMock(IBackend::class);
 		$backend4 = $this->createMock(IBackend::class);
 
-		$res6 = $this->createMock(IResource::class);
-		$res7 = $this->createMock(IResource::class);
-		$res8 = $this->createMock(IResource::class);
+		$res6 = $this->createMock([IResource::class, IMetadataProvider::class]);
+		$res7 = $this->createMock([IResource::class, IMetadataProvider::class]);
+		$res8 = $this->createMock([IResource::class, IMetadataProvider::class]);
 		$res9 = $this->createMock(IResource::class);
 
 		$backend2->method('getBackendIdentifier')
@@ -136,17 +141,51 @@ class UpdateCalendarResourcesRoomsBackgroundJobTest extends TestCase {
 		$res6->method('getEMail')->will($this->returnValue('res6@foo.bar'));
 		$res6->method('getBackend')->will($this->returnValue($backend3));
 
+		$res6->method('getAllAvailableMetadataKeys')->will($this->returnValue(['meta99', 'meta123']));
+		$res6->method('getMetadataForKey')->will($this->returnCallback(function($key) {
+			switch($key) {
+				case 'meta99':
+					return 'value99-new';
+
+				case 'meta123':
+					return 'meta456';
+
+				default:
+					return null;
+			}
+		}));
+
 		$res7->method('getId')->will($this->returnValue('res7'));
 		$res7->method('getDisplayName')->will($this->returnValue('Resource4'));
 		$res7->method('getGroupRestrictions')->will($this->returnValue(['biz']));
 		$res7->method('getEMail')->will($this->returnValue('res7@foo.bar'));
 		$res7->method('getBackend')->will($this->returnValue($backend3));
+		$res7->method('getAllAvailableMetadataKeys')->will($this->returnValue(['meta1']));
+		$res7->method('getMetadataForKey')->will($this->returnCallback(function($key) {
+			switch($key) {
+				case 'meta1':
+					return 'value1';
+
+				default:
+					return null;
+			}
+		}));
 
 		$res8->method('getId')->will($this->returnValue('res8'));
 		$res8->method('getDisplayName')->will($this->returnValue('Beamer'));
 		$res8->method('getGroupRestrictions')->will($this->returnValue([]));
 		$res8->method('getEMail')->will($this->returnValue('res8@foo.bar'));
 		$res8->method('getBackend')->will($this->returnValue($backend4));
+		$res8->method('getAllAvailableMetadataKeys')->will($this->returnValue(['meta2']));
+		$res8->method('getMetadataForKey')->will($this->returnCallback(function($key) {
+			switch($key) {
+				case 'meta2':
+					return 'value2';
+
+				default:
+					return null;
+			}
+		}));
 
 		$res9->method('getId')->will($this->returnValue('res9'));
 		$res9->method('getDisplayName')->will($this->returnValue('Beamer2'));
@@ -173,14 +212,30 @@ class UpdateCalendarResourcesRoomsBackgroundJobTest extends TestCase {
 		$query->select('*')->from('calendar_resources');
 
 		$rows = [];
+		$ids = [];
 		$stmt = $query->execute();
 		while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+			$ids[$row['backend_id'] . '::' . $row['resource_id']] = $row['id'];
 			unset($row['id']);
 			$rows[] = $row;
 		}
 
 		$this->assertEquals([
 			[
+				'backend_id' => 'backend1',
+				'resource_id' => 'res1',
+				'displayname' => 'Beamer1',
+				'email' => 'res1@foo.bar',
+				'group_restrictions' => '[]',
+			],
+			[
+				'backend_id' => 'backend1',
+				'resource_id' => 'res2',
+				'displayname' => 'TV1',
+				'email' => 'res2@foo.bar',
+				'group_restrictions' => '[]',
+			],
+			[
 				'backend_id' => 'backend2',
 				'resource_id' => 'res3',
 				'displayname' => 'Beamer2',
@@ -223,6 +278,59 @@ class UpdateCalendarResourcesRoomsBackgroundJobTest extends TestCase {
 				'group_restrictions' => '[]',
 			],
 		], $rows);
+
+		$query2 = self::$realDatabase->getQueryBuilder();
+		$query2->select('*')->from('calendar_resources_md');
+
+		$rows2 = [];
+		$stmt = $query2->execute();
+		while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+			unset($row['id']);
+			$rows2[] = $row;
+		}
+
+		$this->assertEquals([
+			[
+				'resource_id' => $ids['backend2::res3'],
+				'key' => 'meta1',
+				'value' => 'value1',
+			],
+			[
+				'resource_id' => $ids['backend2::res3'],
+				'key' => 'meta2',
+				'value' => 'value2',
+			],
+			[
+				'resource_id' => $ids['backend2::res4'],
+				'key' => 'meta1',
+				'value' => 'value1',
+			],
+			[
+				'resource_id' => $ids['backend2::res4'],
+				'key' => 'meta3',
+				'value' => 'value3-old',
+			],
+			[
+				'resource_id' => $ids['backend3::res6'],
+				'key' => 'meta99',
+				'value' => 'value99-new',
+			],
+			[
+				'resource_id' => $ids['backend3::res7'],
+				'key' => 'meta1',
+				'value' => 'value1',
+			],
+			[
+				'resource_id' => $ids['backend3::res6'],
+				'key' => 'meta123',
+				'value' => 'meta456',
+			],
+			[
+				'resource_id' => $ids['backend4::res8'],
+				'key' => 'meta2',
+				'value' => 'value2',
+			]
+		], $rows2);
 	}
 
 	protected function createTestResourcesInCache() {
@@ -236,6 +344,7 @@ class UpdateCalendarResourcesRoomsBackgroundJobTest extends TestCase {
 				'group_restrictions' => $query->createNamedParameter('[]'),
 			])
 			->execute();
+
 		$query->insert('calendar_resources')
 			->values([
 				'backend_id' => $query->createNamedParameter('backend1'),
@@ -245,6 +354,7 @@ class UpdateCalendarResourcesRoomsBackgroundJobTest extends TestCase {
 				'group_restrictions' => $query->createNamedParameter('[]'),
 			])
 			->execute();
+
 		$query->insert('calendar_resources')
 			->values([
 				'backend_id' => $query->createNamedParameter('backend2'),
@@ -254,6 +364,8 @@ class UpdateCalendarResourcesRoomsBackgroundJobTest extends TestCase {
 				'group_restrictions' => $query->createNamedParameter('[]'),
 			])
 			->execute();
+		$id3 = $query->getLastInsertId();
+
 		$query->insert('calendar_resources')
 			->values([
 				'backend_id' => $query->createNamedParameter('backend2'),
@@ -263,6 +375,8 @@ class UpdateCalendarResourcesRoomsBackgroundJobTest extends TestCase {
 				'group_restrictions' => $query->createNamedParameter('[]'),
 			])
 			->execute();
+		$id4 = $query->getLastInsertId();
+
 		$query->insert('calendar_resources')
 			->values([
 				'backend_id' => $query->createNamedParameter('backend3'),
@@ -272,6 +386,7 @@ class UpdateCalendarResourcesRoomsBackgroundJobTest extends TestCase {
 				'group_restrictions' => $query->createNamedParameter('[]'),
 			])
 			->execute();
+
 		$query->insert('calendar_resources')
 			->values([
 				'backend_id' => $query->createNamedParameter('backend3'),
@@ -281,5 +396,42 @@ class UpdateCalendarResourcesRoomsBackgroundJobTest extends TestCase {
 				'group_restrictions' => $query->createNamedParameter('["foo", "bar"]'),
 			])
 			->execute();
+		$id6 = $query->getLastInsertId();
+
+		$query->insert('calendar_resources_md')
+			->values([
+				'resource_id' => $query->createNamedParameter($id3),
+				'key' => $query->createNamedParameter('meta1'),
+				'value' => $query->createNamedParameter('value1')
+			])
+			->execute();
+		$query->insert('calendar_resources_md')
+			->values([
+				'resource_id' => $query->createNamedParameter($id3),
+				'key' => $query->createNamedParameter('meta2'),
+				'value' => $query->createNamedParameter('value2')
+			])
+			->execute();
+		$query->insert('calendar_resources_md')
+			->values([
+				'resource_id' => $query->createNamedParameter($id4),
+				'key' => $query->createNamedParameter('meta1'),
+				'value' => $query->createNamedParameter('value1')
+			])
+			->execute();
+		$query->insert('calendar_resources_md')
+			->values([
+				'resource_id' => $query->createNamedParameter($id4),
+				'key' => $query->createNamedParameter('meta3'),
+				'value' => $query->createNamedParameter('value3-old')
+			])
+			->execute();
+		$query->insert('calendar_resources_md')
+			->values([
+				'resource_id' => $query->createNamedParameter($id6),
+				'key' => $query->createNamedParameter('meta99'),
+				'value' => $query->createNamedParameter('value99')
+			])
+			->execute();
 	}
 }
diff --git a/apps/dav/tests/unit/CalDAV/ResourceBooking/AbstractPrincipalBackendTest.php b/apps/dav/tests/unit/CalDAV/ResourceBooking/AbstractPrincipalBackendTest.php
index 19da1782ccd..f4019d86e2b 100644
--- a/apps/dav/tests/unit/CalDAV/ResourceBooking/AbstractPrincipalBackendTest.php
+++ b/apps/dav/tests/unit/CalDAV/ResourceBooking/AbstractPrincipalBackendTest.php
@@ -22,7 +22,6 @@
 namespace OCA\DAV\Tests\unit\CalDAV\ResourceBooking;
 
 use OCP\DB\QueryBuilder\IQueryBuilder;
-use OCP\IDBConnection;
 use OCP\IGroupManager;
 use OCP\ILogger;
 use OCP\IUser;
@@ -35,9 +34,6 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 	/** @var \OCA\DAV\CalDAV\ResourceBooking\ResourcePrincipalBackend|\OCA\DAV\CalDAV\ResourceBooking\RoomPrincipalBackend */
 	protected $principalBackend;
 
-	/** @var IDBConnection|\PHPUnit_Framework_MockObject_MockObject */
-	protected $dbConnection;
-
 	/** @var IUserSession|\PHPUnit_Framework_MockObject_MockObject */
 	protected $userSession;
 
@@ -48,7 +44,13 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 	protected $logger;
 
 	/** @var string */
-	protected $expectedDbTable;
+	protected $mainDbTable;
+
+	/** @var string */
+	protected $metadataDbTable;
+
+	/** @var string */
+	protected $foreignKey;
 
 	/** @var string */
 	protected $principalPrefix;
@@ -59,222 +61,92 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 	public function setUp() {
 		parent::setUp();
 
-		$this->dbConnection = $this->createMock(IDBConnection::class);
 		$this->userSession = $this->createMock(IUserSession::class);
 		$this->groupManager = $this->createMock(IGroupManager::class);
 		$this->logger = $this->createMock(ILogger::class);
 	}
 
-	public function testGetPrincipalsByPrefix() {
-		$queryBuilder = $this->createMock(IQueryBuilder::class);
-		$stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$this->dbConnection->expects($this->once())
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder));
-
-		$queryBuilder->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname'])
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(2))
-			->method('execute')
-			->with()
-			->will($this->returnValue($stmt));
+	protected function tearDown() {
+		$query = self::$realDatabase->getQueryBuilder();
 
-		$stmt->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 0,
-				'backend_id' => 'db',
-				'resource_id' => '123',
-				'email' => 'foo@bar.com',
-				'displayname' => 'Resource 123'
-			]));
-		$stmt->expects($this->at(1))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 1,
-				'backend_id' => 'ldap',
-				'resource_id' => '123',
-				'email' => 'ldap@bar.com',
-				'displayname' => 'Resource 123 ldap'
-			]));
-		$stmt->expects($this->at(2))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 2,
-				'backend_id' => 'db',
-				'resource_id' => '456',
-				'email' => 'bli@bar.com',
-				'displayname' => 'Resource 456'
-			]));
-		$stmt->expects($this->at(3))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue(null));
-		$stmt->expects($this->at(4))
-			->method('closeCursor')
-			->with();
+		$query->delete('calendar_resources')->execute();
+		$query->delete('calendar_resources_md')->execute();
+		$query->delete('calendar_rooms')->execute();
+		$query->delete('calendar_rooms_md')->execute();
+	}
 
+	public function testGetPrincipalsByPrefix() {
 		$actual = $this->principalBackend->getPrincipalsByPrefix($this->principalPrefix);
+
 		$this->assertEquals([
 			[
-				'uri' => $this->principalPrefix . '/db-123',
-				'{DAV:}displayname' => 'Resource 123',
-				'{http://sabredav.org/ns}email-address' => 'foo@bar.com',
+				'uri' => $this->principalPrefix . '/backend1-res1',
+				'{DAV:}displayname' => 'Beamer1',
+				'{http://sabredav.org/ns}email-address' => 'res1@foo.bar',
 				'{urn:ietf:params:xml:ns:caldav}calendar-user-type' => $this->expectedCUType,
 			],
 			[
-				'uri' => $this->principalPrefix . '/ldap-123',
-				'{DAV:}displayname' => 'Resource 123 ldap',
-				'{http://sabredav.org/ns}email-address' => 'ldap@bar.com',
+				'uri' => $this->principalPrefix . '/backend1-res2',
+				'{DAV:}displayname' => 'TV1',
+				'{http://sabredav.org/ns}email-address' => 'res2@foo.bar',
 				'{urn:ietf:params:xml:ns:caldav}calendar-user-type' => $this->expectedCUType,
 			],
 			[
-				'uri' => $this->principalPrefix . '/db-456',
-				'{DAV:}displayname' => 'Resource 456',
-				'{http://sabredav.org/ns}email-address' => 'bli@bar.com',
+				'uri' => $this->principalPrefix . '/backend2-res3',
+				'{DAV:}displayname' => 'Beamer2',
+				'{http://sabredav.org/ns}email-address' => 'res3@foo.bar',
 				'{urn:ietf:params:xml:ns:caldav}calendar-user-type' => $this->expectedCUType,
+				'{http://nextcloud.com/ns}foo' => 'value1',
+				'{http://nextcloud.com/ns}meta2' => 'value2',
 			],
+			[
+				'uri' => $this->principalPrefix . '/backend2-res4',
+				'{DAV:}displayname' => 'TV2',
+				'{http://sabredav.org/ns}email-address' => 'res4@foo.bar',
+				'{urn:ietf:params:xml:ns:caldav}calendar-user-type' => $this->expectedCUType,
+				'{http://nextcloud.com/ns}meta1' => 'value1',
+				'{http://nextcloud.com/ns}meta3' => 'value3-old',
+			],
+			[
+				'uri' => $this->principalPrefix . '/backend3-res5',
+				'{DAV:}displayname' => 'Beamer3',
+				'{http://sabredav.org/ns}email-address' => 'res5@foo.bar',
+				'{urn:ietf:params:xml:ns:caldav}calendar-user-type' => $this->expectedCUType,
+			],
+			[
+				'uri' => $this->principalPrefix . '/backend3-res6',
+				'{DAV:}displayname' => 'Pointer',
+				'{http://sabredav.org/ns}email-address' => 'res6@foo.bar',
+				'{urn:ietf:params:xml:ns:caldav}calendar-user-type' => $this->expectedCUType,
+				'{http://nextcloud.com/ns}meta99' => 'value99'
+			]
 		], $actual);
 
 	}
 
 	public function testGetNoPrincipalsByPrefixForWrongPrincipalPrefix() {
-		$this->dbConnection->expects($this->never())
-			->method('getQueryBuilder');
-
 		$actual = $this->principalBackend->getPrincipalsByPrefix('principals/users');
 		$this->assertEquals([], $actual);
 	}
 
 	public function testGetPrincipalByPath() {
-		$queryBuilder = $this->createMock(IQueryBuilder::class);
-		$stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
-
-		$this->dbConnection->expects($this->at(0))
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->method('expr')
-			->will($this->returnValue($expr));
-		$expr->method('eq')
-			->will($this->returnValueMap([
-				['backend_id', 'createNamedParameter-1', null, 'WHERE_CLAUSE_1'],
-				['resource_id', 'createNamedParameter-2', null, 'WHERE_CLAUSE_2'],
-			]));
-		$queryBuilder->method('createNamedParameter')
-			->will($this->returnValueMap([
-				['db', \PDO::PARAM_STR, null, 'createNamedParameter-1'],
-				['123', \PDO::PARAM_STR, null, 'createNamedParameter-2'],
-			]));
-
-		$queryBuilder->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname'])
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(4))
-			->method('where')
-			->with('WHERE_CLAUSE_1')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(7))
-			->method('andWhere')
-			->with('WHERE_CLAUSE_2')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(8))
-			->method('execute')
-			->with()
-			->will($this->returnValue($stmt));
-
-		$stmt->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 0,
-				'backend_id' => 'db',
-				'resource_id' => '123',
-				'email' => 'foo@bar.com',
-				'displayname' => 'Resource 123'
-			]));
-
-		$actual = $this->principalBackend->getPrincipalByPath($this->principalPrefix . '/db-123');
+		$actual = $this->principalBackend->getPrincipalByPath($this->principalPrefix . '/backend2-res3');
 		$this->assertEquals([
-			'uri' => $this->principalPrefix . '/db-123',
-			'{DAV:}displayname' => 'Resource 123',
-			'{http://sabredav.org/ns}email-address' => 'foo@bar.com',
+			'uri' => $this->principalPrefix . '/backend2-res3',
+			'{DAV:}displayname' => 'Beamer2',
+			'{http://sabredav.org/ns}email-address' => 'res3@foo.bar',
 			'{urn:ietf:params:xml:ns:caldav}calendar-user-type' => $this->expectedCUType,
+			'{http://nextcloud.com/ns}foo' => 'value1',
+			'{http://nextcloud.com/ns}meta2' => 'value2',
 		], $actual);
 	}
 
 	public function testGetPrincipalByPathNotFound() {
-		$queryBuilder = $this->createMock(IQueryBuilder::class);
-		$stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
-
-		$this->dbConnection->expects($this->at(0))
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->method('expr')
-			->will($this->returnValue($expr));
-		$expr->method('eq')
-			->will($this->returnValueMap([
-				['backend_id', 'createNamedParameter-1', null, 'WHERE_CLAUSE_1'],
-				['resource_id', 'createNamedParameter-2', null, 'WHERE_CLAUSE_2'],
-			]));
-		$queryBuilder->method('createNamedParameter')
-			->will($this->returnValueMap([
-				['db', \PDO::PARAM_STR, null, 'createNamedParameter-1'],
-				['123', \PDO::PARAM_STR, null, 'createNamedParameter-2'],
-			]));
-
-		$queryBuilder->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname'])
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(4))
-			->method('where')
-			->with('WHERE_CLAUSE_1')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(7))
-			->method('andWhere')
-			->with('WHERE_CLAUSE_2')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(8))
-			->method('execute')
-			->with()
-			->will($this->returnValue($stmt));
-
-		$stmt->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue(false));
-
 		$actual = $this->principalBackend->getPrincipalByPath($this->principalPrefix . '/db-123');
 		$this->assertEquals(null, $actual);
 	}
 
 	public function testGetPrincipalByPathWrongPrefix() {
-		$this->dbConnection->expects($this->never())
-			->method('getQueryBuilder');
-
 		$actual = $this->principalBackend->getPrincipalByPath('principals/users/foo-bar');
 		$this->assertEquals(null, $actual);
 	}
@@ -318,182 +190,9 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 			->with($user)
 			->will($this->returnValue(['group1', 'group2']));
 
-		$queryBuilder1 = $this->createMock(IQueryBuilder::class);
-		$queryBuilder2 = $this->createMock(IQueryBuilder::class);
-		$stmt1 = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$stmt2 = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$expr1 = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
-		$expr2 = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
-
-		$this->dbConnection->expects($this->at(0))
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder1));
-		$this->dbConnection->expects($this->at(1))
-			->method('escapeLikeParameter')
-			->with('foo')
-			->will($this->returnValue('escapedFoo'));
-		$this->dbConnection->expects($this->at(2))
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder2));
-		$this->dbConnection->expects($this->at(3))
-			->method('escapeLikeParameter')
-			->with('bar')
-			->will($this->returnValue('escapedBar'));
-
-		$queryBuilder1->method('expr')
-			->will($this->returnValue($expr1));
-		$queryBuilder2->method('expr')
-			->will($this->returnValue($expr2));
-
-		$expr1->method('iLike')
-			->will($this->returnValueMap([
-				['email', 'createNamedParameter-1', null, 'ILIKE_CLAUSE_1'],
-			]));
-		$expr2->method('iLike')
-			->will($this->returnValueMap([
-				['displayname', 'createNamedParameter-2', null, 'ILIKE_CLAUSE_2'],
-			]));
-
-		$queryBuilder1->method('expr')
-			->will($this->returnValue($expr1));
-		$queryBuilder2->method('expr')
-			->will($this->returnValue($expr2));
-
-		$queryBuilder1->method('createNamedParameter')
-			->will($this->returnValueMap([
-				['%escapedFoo%', \PDO::PARAM_STR, null, 'createNamedParameter-1'],
-			]));
-		$queryBuilder2->method('createNamedParameter')
-			->will($this->returnValueMap([
-				['%escapedBar%', \PDO::PARAM_STR, null, 'createNamedParameter-2'],
-			]));
-
-		$queryBuilder1->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
-			->will($this->returnValue($queryBuilder1));
-		$queryBuilder1->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder1));
-		$queryBuilder1->expects($this->at(4))
-			->method('where')
-			->with('ILIKE_CLAUSE_1')
-			->will($this->returnValue($queryBuilder1));
-		$queryBuilder1->expects($this->at(5))
-			->method('execute')
-			->with()
-			->will($this->returnValue($stmt1));
-
-		$queryBuilder2->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
-			->will($this->returnValue($queryBuilder2));
-		$queryBuilder2->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder2));
-		$queryBuilder2->expects($this->at(4))
-			->method('where')
-			->with('ILIKE_CLAUSE_2')
-			->will($this->returnValue($queryBuilder2));
-		$queryBuilder2->expects($this->at(5))
-			->method('execute')
-			->with()
-			->will($this->returnValue($stmt2));
-
-		$stmt1->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 0,
-				'backend_id' => 'db',
-				'resource_id' => '1',
-				'email' => '1',
-				'displayname' => 'Resource 1',
-				'group_restrictions' => null,
-			]));
-		$stmt1->expects($this->at(1))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 1,
-				'backend_id' => 'db',
-				'resource_id' => '2',
-				'email' => '2',
-				'displayname' => 'Resource 2',
-				'group_restrictions' => '',
-			]));
-		$stmt1->expects($this->at(2))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 2,
-				'backend_id' => 'db',
-				'resource_id' => '3',
-				'email' => '3',
-				'displayname' => 'Resource 3',
-				'group_restrictions' => '["group3"]',
-			]));
-		$stmt1->expects($this->at(3))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 99,
-				'backend_id' => 'db',
-				'resource_id' => '99',
-				'email' => '99',
-				'displayname' => 'Resource 99',
-				'group_restrictions' => '["group1", "group2"]',
-			]));
-		$stmt1->expects($this->at(4))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue(null));
-
-		$stmt2->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 0,
-				'backend_id' => 'db',
-				'resource_id' => '4',
-				'email' => '4',
-				'displayname' => 'Resource 4',
-				'group_restrictions' => '[]'
-			]));
-		$stmt2->expects($this->at(1))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 1,
-				'backend_id' => 'db',
-				'resource_id' => '5',
-				'email' => '5',
-				'displayname' => 'Resource 5',
-				'group_restrictions' => '["group1", "group5"]'
-			]));
-		$stmt2->expects($this->at(2))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 99,
-				'backend_id' => 'db',
-				'resource_id' => '99',
-				'email' => '99',
-				'displayname' => 'Resource 99',
-				'group_restrictions' => '["group1", "group2"]',
-			]));
-		$stmt2->expects($this->at(3))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue(null));
-
 		$actual = $this->principalBackend->searchPrincipals($this->principalPrefix, [
 			'{http://sabredav.org/ns}email-address' => 'foo',
-			'{DAV:}displayname' => 'bar',
+			'{DAV:}displayname' => 'Beamer',
 		], $test);
 
 		$this->assertEquals(
@@ -507,133 +206,55 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 		// at that point, so we need this hack
 		return [
 			[[
-				'%prefix%/db-99'
+				'%prefix%/backend1-res1',
+				'%prefix%/backend2-res3',
 			], 'allof'],
 			[[
-				'%prefix%/db-1',
-				'%prefix%/db-2',
-				'%prefix%/db-99',
-				'%prefix%/db-4',
-				'%prefix%/db-5',
+				'%prefix%/backend1-res1',
+				'%prefix%/backend1-res2',
+				'%prefix%/backend2-res3',
+				'%prefix%/backend2-res4',
+				'%prefix%/backend3-res6',
 			], 'anyof'],
 		];
 	}
 
-	public function testSearchPrincipalsByCalendarUserAddressSet() {
+	public function testSearchPrincipalsByMetadataKey() {
 		$user = $this->createMock(IUser::class);
-		$this->userSession->expects($this->exactly(2))
+		$this->userSession->expects($this->once())
 			->method('getUser')
 			->with()
 			->will($this->returnValue($user));
-		$this->groupManager->expects($this->exactly(2))
+		$this->groupManager->expects($this->once())
 			->method('getUserGroupIds')
 			->with($user)
 			->will($this->returnValue(['group1', 'group2']));
 
-		$queryBuilder1 = $this->createMock(IQueryBuilder::class);
-		$stmt1 = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$expr1 = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
-
-		$this->dbConnection->expects($this->at(0))
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder1));
-		$this->dbConnection->expects($this->at(1))
-			->method('escapeLikeParameter')
-			->with('foo')
-			->will($this->returnValue('escapedFoo'));
-
-		$queryBuilder1->method('expr')
-			->will($this->returnValue($expr1));
-
-		$expr1->method('iLike')
-			->will($this->returnValueMap([
-				['email', 'createNamedParameter-1', null, 'ILIKE_CLAUSE_1'],
-			]));
-
-		$queryBuilder1->method('expr')
-			->will($this->returnValue($expr1));
+		$actual = $this->principalBackend->searchPrincipals($this->principalPrefix, [
+			'{http://nextcloud.com/ns}meta3' => 'value',
+		]);
 
-		$queryBuilder1->method('createNamedParameter')
-			->will($this->returnValueMap([
-				['%escapedFoo%', \PDO::PARAM_STR, null, 'createNamedParameter-1'],
-			]));
+		$this->assertEquals([
+			$this->principalPrefix . '/backend2-res4',
+		], $actual);
+	}
 
-		$queryBuilder1->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
-			->will($this->returnValue($queryBuilder1));
-		$queryBuilder1->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder1));
-		$queryBuilder1->expects($this->at(4))
-			->method('where')
-			->with('ILIKE_CLAUSE_1')
-			->will($this->returnValue($queryBuilder1));
-		$queryBuilder1->expects($this->at(5))
-			->method('execute')
+	public function testSearchPrincipalsByCalendarUserAddressSet() {
+		$user = $this->createMock(IUser::class);
+		$this->userSession->method('getUser')
 			->with()
-			->will($this->returnValue($stmt1));
-
-		$stmt1->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 0,
-				'backend_id' => 'db',
-				'resource_id' => '1',
-				'email' => '1',
-				'displayname' => 'Resource 1',
-				'group_restrictions' => null,
-			]));
-		$stmt1->expects($this->at(1))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 1,
-				'backend_id' => 'db',
-				'resource_id' => '2',
-				'email' => '2',
-				'displayname' => 'Resource 2',
-				'group_restrictions' => '',
-			]));
-		$stmt1->expects($this->at(2))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 2,
-				'backend_id' => 'db',
-				'resource_id' => '3',
-				'email' => '3',
-				'displayname' => 'Resource 3',
-				'group_restrictions' => '["group3"]',
-			]));
-		$stmt1->expects($this->at(3))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 99,
-				'backend_id' => 'db',
-				'resource_id' => '99',
-				'email' => '99',
-				'displayname' => 'Resource 99',
-				'group_restrictions' => '["group1", "group2"]',
-			]));
-		$stmt1->expects($this->at(4))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue(null));
+			->will($this->returnValue($user));
+		$this->groupManager->method('getUserGroupIds')
+			->with($user)
+			->will($this->returnValue(['group1', 'group2']));
 
 		$actual = $this->principalBackend->searchPrincipals($this->principalPrefix, [
-			'{urn:ietf:params:xml:ns:caldav}calendar-user-address-set' => 'foo',
+			'{urn:ietf:params:xml:ns:caldav}calendar-user-address-set' => 'res2@foo.bar',
 		]);
 
 		$this->assertEquals(
 			str_replace('%prefix%', $this->principalPrefix, [
-				'%prefix%/db-1',
-				'%prefix%/db-2',
-				'%prefix%/db-99',
+				'%prefix%/backend1-res2',
 			]),
 			$actual);
 	}
@@ -643,8 +264,6 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 			->method('getUser');
 		$this->groupManager->expects($this->never())
 			->method('getUserGroupIds');
-		$this->dbConnection->expects($this->never())
-			->method('getQueryBuilder');
 
 		$this->principalBackend->searchPrincipals($this->principalPrefix, []);
 	}
@@ -654,8 +273,6 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 			->method('getUser');
 		$this->groupManager->expects($this->never())
 			->method('getUserGroupIds');
-		$this->dbConnection->expects($this->never())
-			->method('getQueryBuilder');
 
 		$this->principalBackend->searchPrincipals('principals/users', [
 			'{http://sabredav.org/ns}email-address' => 'foo'
@@ -673,56 +290,8 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 			->with($user)
 			->will($this->returnValue(['group1', 'group2']));
 
-		$queryBuilder = $this->createMock(IQueryBuilder::class);
-		$stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
-
-		$this->dbConnection->expects($this->at(0))
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->method('expr')
-			->will($this->returnValue($expr));
-		$expr->method('eq')
-			->will($this->returnValueMap([
-				['email', 'createNamedParameter-1', null, 'WHERE_CLAUSE_1'],
-			]));
-		$queryBuilder->method('createNamedParameter')
-			->will($this->returnValueMap([
-				['foo@bar.com', \PDO::PARAM_STR, null, 'createNamedParameter-1'],
-			]));
-
-		$queryBuilder->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(4))
-			->method('where')
-			->with('WHERE_CLAUSE_1')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(5))
-			->method('execute')
-			->with()
-			->will($this->returnValue($stmt));
-
-		$stmt->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 0,
-				'backend_id' => 'db',
-				'resource_id' => '123',
-				'email' => 'foo@bar.com',
-				'displayname' => 'Resource 123',
-				'group_restrictions' => '["group1"]',
-			]));
-
-		$actual = $this->principalBackend->findByUri('mailto:foo@bar.com', $this->principalPrefix);
-		$this->assertEquals($this->principalPrefix . '/db-123', $actual);
+		$actual = $this->principalBackend->findByUri('mailto:res1@foo.bar', $this->principalPrefix);
+		$this->assertEquals($this->principalPrefix . '/backend1-res1', $actual);
 	}
 
 	public function testFindByUriByEmailForbiddenResource() {
@@ -736,55 +305,7 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 			->with($user)
 			->will($this->returnValue(['group1', 'group2']));
 
-		$queryBuilder = $this->createMock(IQueryBuilder::class);
-		$stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
-
-		$this->dbConnection->expects($this->at(0))
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->method('expr')
-			->will($this->returnValue($expr));
-		$expr->method('eq')
-			->will($this->returnValueMap([
-				['email', 'createNamedParameter-1', null, 'WHERE_CLAUSE_1'],
-			]));
-		$queryBuilder->method('createNamedParameter')
-			->will($this->returnValueMap([
-				['foo@bar.com', \PDO::PARAM_STR, null, 'createNamedParameter-1'],
-			]));
-
-		$queryBuilder->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(4))
-			->method('where')
-			->with('WHERE_CLAUSE_1')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(5))
-			->method('execute')
-			->with()
-			->will($this->returnValue($stmt));
-
-		$stmt->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 0,
-				'backend_id' => 'db',
-				'resource_id' => '123',
-				'email' => 'foo@bar.com',
-				'displayname' => 'Resource 123',
-				'group_restrictions' => '["group3"]',
-			]));
-
-		$actual = $this->principalBackend->findByUri('mailto:foo@bar.com', $this->principalPrefix);
+		$actual = $this->principalBackend->findByUri('mailto:res5@foo.bar', $this->principalPrefix);
 		$this->assertEquals(null, $actual);
 	}
 
@@ -799,48 +320,7 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 			->with($user)
 			->will($this->returnValue(['group1', 'group2']));
 
-		$queryBuilder = $this->createMock(IQueryBuilder::class);
-		$stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
-
-		$this->dbConnection->expects($this->at(0))
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->method('expr')
-			->will($this->returnValue($expr));
-		$expr->method('eq')
-			->will($this->returnValueMap([
-				['email', 'createNamedParameter-1', null, 'WHERE_CLAUSE_1'],
-			]));
-		$queryBuilder->method('createNamedParameter')
-			->will($this->returnValueMap([
-				['foo@bar.com', \PDO::PARAM_STR, null, 'createNamedParameter-1'],
-			]));
-
-		$queryBuilder->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(4))
-			->method('where')
-			->with('WHERE_CLAUSE_1')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(5))
-			->method('execute')
-			->with()
-			->will($this->returnValue($stmt));
-
-		$stmt->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue(null));
-
-		$actual = $this->principalBackend->findByUri('mailto:foo@bar.com', $this->principalPrefix);
+		$actual = $this->principalBackend->findByUri('mailto:res99@foo.bar', $this->principalPrefix);
 		$this->assertEquals(null, $actual);
 	}
 
@@ -855,56 +335,8 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 			->with($user)
 			->will($this->returnValue(['group1', 'group2']));
 
-		$queryBuilder = $this->createMock(IQueryBuilder::class);
-		$stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
-
-		$this->dbConnection->expects($this->at(0))
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->method('expr')
-			->will($this->returnValue($expr));
-		$expr->method('eq')
-			->will($this->returnValueMap([
-				['email', 'createNamedParameter-1', null, 'WHERE_CLAUSE_1'],
-			]));
-		$queryBuilder->method('createNamedParameter')
-			->will($this->returnValueMap([
-				['foo@bar.com', \PDO::PARAM_STR, null, 'createNamedParameter-1'],
-			]));
-
-		$queryBuilder->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(4))
-			->method('where')
-			->with('WHERE_CLAUSE_1')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(5))
-			->method('execute')
-			->with()
-			->will($this->returnValue($stmt));
-
-		$stmt->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 0,
-				'backend_id' => 'db',
-				'resource_id' => '123',
-				'email' => 'foo@bar.com',
-				'displayname' => 'Resource 123',
-				'group_restrictions' => '["group1"]',
-			]));
-
-		$actual = $this->principalBackend->findByUri('mailto:foo@bar.com', $this->principalPrefix);
-		$this->assertEquals($this->principalPrefix . '/db-123', $actual);
+		$actual = $this->principalBackend->findByUri('mailto:res6@foo.bar', $this->principalPrefix);
+		$this->assertEquals($this->principalPrefix . '/backend3-res6', $actual);
 	}
 
 	public function testFindByUriByPrincipalForbiddenResource() {
@@ -918,61 +350,7 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 			->with($user)
 			->will($this->returnValue(['group1', 'group2']));
 
-		$queryBuilder = $this->createMock(IQueryBuilder::class);
-		$stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
-
-		$this->dbConnection->expects($this->at(0))
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->method('expr')
-			->will($this->returnValue($expr));
-		$expr->method('eq')
-			->will($this->returnValueMap([
-				['backend_id', 'createNamedParameter-1', null, 'WHERE_CLAUSE_1'],
-				['resource_id', 'createNamedParameter-2', null, 'WHERE_CLAUSE_2'],
-			]));
-		$queryBuilder->method('createNamedParameter')
-			->will($this->returnValueMap([
-				['db', \PDO::PARAM_STR, null, 'createNamedParameter-1'],
-				['123', \PDO::PARAM_STR, null, 'createNamedParameter-2'],
-			]));
-
-		$queryBuilder->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(4))
-			->method('where')
-			->with('WHERE_CLAUSE_1')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(7))
-			->method('andWhere')
-			->with('WHERE_CLAUSE_2')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(8))
-			->method('execute')
-			->with()
-			->will($this->returnValue($stmt));
-
-		$stmt->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue([
-				'id' => 0,
-				'backend_id' => 'db',
-				'resource_id' => '123',
-				'email' => 'foo@bar.com',
-				'displayname' => 'Resource 123',
-				'group_restrictions' => '["group3"]',
-			]));
-
-		$actual = $this->principalBackend->findByUri('principal:' . $this->principalPrefix . '/db-123', $this->principalPrefix);
+		$actual = $this->principalBackend->findByUri('principal:' . $this->principalPrefix . '/backend3-res5', $this->principalPrefix);
 		$this->assertEquals(null, $actual);
 	}
 
@@ -987,53 +365,6 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 			->with($user)
 			->will($this->returnValue(['group1', 'group2']));
 
-		$queryBuilder = $this->createMock(IQueryBuilder::class);
-		$stmt = $this->createMock(\Doctrine\DBAL\Driver\Statement::class);
-		$expr = $this->createMock(\OCP\DB\QueryBuilder\IExpressionBuilder::class);
-
-		$this->dbConnection->expects($this->at(0))
-			->method('getQueryBuilder')
-			->with()
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->method('expr')
-			->will($this->returnValue($expr));
-		$expr->method('eq')
-			->will($this->returnValueMap([
-				['backend_id', 'createNamedParameter-1', null, 'WHERE_CLAUSE_1'],
-				['resource_id', 'createNamedParameter-2', null, 'WHERE_CLAUSE_2'],
-			]));
-		$queryBuilder->method('createNamedParameter')
-			->will($this->returnValueMap([
-				['db', \PDO::PARAM_STR, null, 'createNamedParameter-1'],
-				['123', \PDO::PARAM_STR, null, 'createNamedParameter-2'],
-			]));
-
-		$queryBuilder->expects($this->at(0))
-			->method('select')
-			->with(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(1))
-			->method('from')
-			->with($this->expectedDbTable)
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(4))
-			->method('where')
-			->with('WHERE_CLAUSE_1')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(7))
-			->method('andWhere')
-			->with('WHERE_CLAUSE_2')
-			->will($this->returnValue($queryBuilder));
-		$queryBuilder->expects($this->at(8))
-			->method('execute')
-			->with()
-			->will($this->returnValue($stmt));
-
-		$stmt->expects($this->at(0))
-			->method('fetch')
-			->with(\PDO::FETCH_ASSOC)
-			->will($this->returnValue(null));
-
 		$actual = $this->principalBackend->findByUri('principal:' . $this->principalPrefix . '/db-123', $this->principalPrefix);
 		$this->assertEquals(null, $actual);
 	}
@@ -1053,4 +384,106 @@ abstract class AbstractPrincipalBackendTest extends TestCase {
 		$this->assertEquals(null, $actual);
 	}
 
+	protected function createTestDatasetInDb() {
+		$query = self::$realDatabase->getQueryBuilder();
+		$query->insert($this->mainDbTable)
+			->values([
+				'backend_id' => $query->createNamedParameter('backend1'),
+				'resource_id' => $query->createNamedParameter('res1'),
+				'email' => $query->createNamedParameter('res1@foo.bar'),
+				'displayname' => $query->createNamedParameter('Beamer1'),
+				'group_restrictions' => $query->createNamedParameter('[]'),
+			])
+			->execute();
+
+		$query->insert($this->mainDbTable)
+			->values([
+				'backend_id' => $query->createNamedParameter('backend1'),
+				'resource_id' => $query->createNamedParameter('res2'),
+				'email' => $query->createNamedParameter('res2@foo.bar'),
+				'displayname' => $query->createNamedParameter('TV1'),
+				'group_restrictions' => $query->createNamedParameter('[]'),
+			])
+			->execute();
+
+		$query->insert($this->mainDbTable)
+			->values([
+				'backend_id' => $query->createNamedParameter('backend2'),
+				'resource_id' => $query->createNamedParameter('res3'),
+				'email' => $query->createNamedParameter('res3@foo.bar'),
+				'displayname' => $query->createNamedParameter('Beamer2'),
+				'group_restrictions' => $query->createNamedParameter('[]'),
+			])
+			->execute();
+		$id3 = $query->getLastInsertId();
+
+		$query->insert($this->mainDbTable)
+			->values([
+				'backend_id' => $query->createNamedParameter('backend2'),
+				'resource_id' => $query->createNamedParameter('res4'),
+				'email' => $query->createNamedParameter('res4@foo.bar'),
+				'displayname' => $query->createNamedParameter('TV2'),
+				'group_restrictions' => $query->createNamedParameter('[]'),
+			])
+			->execute();
+		$id4 = $query->getLastInsertId();
+
+		$query->insert($this->mainDbTable)
+			->values([
+				'backend_id' => $query->createNamedParameter('backend3'),
+				'resource_id' => $query->createNamedParameter('res5'),
+				'email' => $query->createNamedParameter('res5@foo.bar'),
+				'displayname' => $query->createNamedParameter('Beamer3'),
+				'group_restrictions' => $query->createNamedParameter('["foo", "bar"]'),
+			])
+			->execute();
+
+		$query->insert($this->mainDbTable)
+			->values([
+				'backend_id' => $query->createNamedParameter('backend3'),
+				'resource_id' => $query->createNamedParameter('res6'),
+				'email' => $query->createNamedParameter('res6@foo.bar'),
+				'displayname' => $query->createNamedParameter('Pointer'),
+				'group_restrictions' => $query->createNamedParameter('["group1", "bar"]'),
+			])
+			->execute();
+		$id6 = $query->getLastInsertId();
+
+		$query->insert($this->metadataDbTable)
+			->values([
+				$this->foreignKey => $query->createNamedParameter($id3),
+				'key' => $query->createNamedParameter('{http://nextcloud.com/ns}foo'),
+				'value' => $query->createNamedParameter('value1')
+			])
+			->execute();
+		$query->insert($this->metadataDbTable)
+			->values([
+				$this->foreignKey => $query->createNamedParameter($id3),
+				'key' => $query->createNamedParameter('{http://nextcloud.com/ns}meta2'),
+				'value' => $query->createNamedParameter('value2')
+			])
+			->execute();
+		$query->insert($this->metadataDbTable)
+			->values([
+				$this->foreignKey => $query->createNamedParameter($id4),
+				'key' => $query->createNamedParameter('{http://nextcloud.com/ns}meta1'),
+				'value' => $query->createNamedParameter('value1')
+			])
+			->execute();
+		$query->insert($this->metadataDbTable)
+			->values([
+				$this->foreignKey => $query->createNamedParameter($id4),
+				'key' => $query->createNamedParameter('{http://nextcloud.com/ns}meta3'),
+				'value' => $query->createNamedParameter('value3-old')
+			])
+			->execute();
+		$query->insert($this->metadataDbTable)
+			->values([
+				$this->foreignKey => $query->createNamedParameter($id6),
+				'key' => $query->createNamedParameter('{http://nextcloud.com/ns}meta99'),
+				'value' => $query->createNamedParameter('value99')
+			])
+			->execute();
+	}
+
 }
diff --git a/apps/dav/tests/unit/CalDAV/ResourceBooking/ResourcePrincipalBackendTest.php b/apps/dav/tests/unit/CalDAV/ResourceBooking/ResourcePrincipalBackendTest.php
index d3c774417c0..3787e4df951 100644
--- a/apps/dav/tests/unit/CalDAV/ResourceBooking/ResourcePrincipalBackendTest.php
+++ b/apps/dav/tests/unit/CalDAV/ResourceBooking/ResourcePrincipalBackendTest.php
@@ -27,10 +27,16 @@ Class ResourcePrincipalBackendTest extends AbstractPrincipalBackendTest {
 	public function setUp() {
 		parent::setUp();
 
-		$this->principalBackend = new ResourcePrincipalBackend($this->dbConnection,
+		$this->principalBackend = new ResourcePrincipalBackend(self::$realDatabase,
 			$this->userSession, $this->groupManager, $this->logger);
-		$this->expectedDbTable = 'calendar_resources';
+
+		$this->mainDbTable = 'calendar_resources';
+		$this->metadataDbTable = 'calendar_resources_md';
+		$this->foreignKey = 'resource_id';
+
 		$this->principalPrefix = 'principals/calendar-resources';
 		$this->expectedCUType = 'RESOURCE';
+
+		$this->createTestDatasetInDb();
 	}
 }
diff --git a/apps/dav/tests/unit/CalDAV/ResourceBooking/RoomPrincipalBackendTest.php b/apps/dav/tests/unit/CalDAV/ResourceBooking/RoomPrincipalBackendTest.php
index a10aaa26b35..9b259c30adf 100644
--- a/apps/dav/tests/unit/CalDAV/ResourceBooking/RoomPrincipalBackendTest.php
+++ b/apps/dav/tests/unit/CalDAV/ResourceBooking/RoomPrincipalBackendTest.php
@@ -27,10 +27,16 @@ Class RoomPrincipalBackendTest extends AbstractPrincipalBackendTest {
 	public function setUp() {
 		parent::setUp();
 
-		$this->principalBackend = new RoomPrincipalBackend($this->dbConnection,
+		$this->principalBackend = new RoomPrincipalBackend(self::$realDatabase,
 			$this->userSession, $this->groupManager, $this->logger);
-		$this->expectedDbTable = 'calendar_rooms';
+
+		$this->mainDbTable = 'calendar_rooms';
+		$this->metadataDbTable = 'calendar_rooms_md';
+		$this->foreignKey = 'room_id';
+
 		$this->principalPrefix = 'principals/calendar-rooms';
 		$this->expectedCUType = 'ROOM';
+
+		$this->createTestDatasetInDb();
 	}
 }