Merge pull request #9773 from nextcloud/feature/noid/resource_booking

resource booking

11 files changed, 953 insertions, 13 deletions

diff --git a/apps/dav/lib/BackgroundJob/UpdateCalendarResourcesRoomsBackgroundJob.php b/apps/dav/lib/BackgroundJob/UpdateCalendarResourcesRoomsBackgroundJob.php
new file mode 100644
index 00000000000..a01540a6292
--- /dev/null
+++ b/apps/dav/lib/BackgroundJob/UpdateCalendarResourcesRoomsBackgroundJob.php
@@ -0,0 +1,337 @@
+<?php
+/**
+ * @copyright 2018, Georg Ehrke <oc.list@georgehrke.com>
+ *
+ * @author Georg Ehrke <oc.list@georgehrke.com>
+ *
+ * @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\DAV\BackgroundJob;
+
+use OC\BackgroundJob\TimedJob;
+use OCA\DAV\CalDAV\CalDavBackend;
+use OCP\Calendar\BackendTemporarilyUnavailableException;
+use OCP\Calendar\Resource\IManager as IResourceManager;
+use OCP\Calendar\Resource\IResource;
+use OCP\Calendar\Room\IManager as IRoomManager;
+use OCP\Calendar\Room\IRoom;
+use OCP\IDBConnection;
+
+class UpdateCalendarResourcesRoomsBackgroundJob extends TimedJob {
+
+	/** @var IResourceManager */
+	private $resourceManager;
+
+	/** @var IRoomManager */
+	private $roomManager;
+
+	/** @var IDBConnection */
+	private $db;
+
+	/** @var CalDavBackend */
+	private $calDavBackend;
+
+	/** @var string */
+	private $resourceDbTable;
+
+	/** @var string */
+	private $resourcePrincipalUri;
+
+	/** @var string */
+	private $roomDbTable;
+
+	/** @var string */
+	private $roomPrincipalUri;
+
+	/**
+	 * UpdateCalendarResourcesRoomsBackgroundJob constructor.
+	 *
+	 * @param IResourceManager $resourceManager
+	 * @param IRoomManager $roomManager
+	 * @param IDBConnection $dbConnection
+	 * @param CalDavBackend $calDavBackend
+	 */
+	public function __construct(IResourceManager $resourceManager, IRoomManager $roomManager,
+								IDBConnection $dbConnection, CalDavBackend $calDavBackend) {
+		$this->resourceManager = $resourceManager;
+		$this->roomManager = $roomManager;
+		$this->db = $dbConnection;
+		$this->calDavBackend = $calDavBackend;
+		$this->resourceDbTable = 'calendar_resources_cache';
+		$this->resourcePrincipalUri = 'principals/calendar-resources';
+		$this->roomDbTable = 'calendar_rooms_cache';
+		$this->roomPrincipalUri = 'principals/calendar-rooms';
+
+		// run once an hour
+		$this->setInterval(60 * 60);
+	}
+
+	/**
+	 * @param $argument
+	 */
+	public function run($argument) {
+		$this->runResources();
+		$this->runRooms();
+	}
+
+	/**
+	 * run timed job for resources
+	 */
+	private function runResources() {
+		$resourceBackends = $this->resourceManager->getBackends();
+		$cachedResources = $this->getCached($this->resourceDbTable);
+		$cachedResourceIds = $this->getCachedResourceIds($cachedResources);
+
+		$remoteResourceIds = [];
+		foreach($resourceBackends as $resourceBackend) {
+			try {
+				$remoteResourceIds[$resourceBackend->getBackendIdentifier()] =
+					$resourceBackend->listAllResources();
+			} catch(BackendTemporarilyUnavailableException $ex) {
+				// If the backend is temporarily unavailable
+				// ignore this backend in this execution
+				unset($cachedResourceIds[$resourceBackend->getBackendIdentifier()]);
+			}
+		}
+
+		$sortedResources = $this->sortByNewDeletedExisting($cachedResourceIds, $remoteResourceIds);
+
+		foreach($sortedResources['new'] as $backendId => $newResources) {
+			foreach ($newResources as $newResource) {
+				$resource = $this->resourceManager->getBackend($backendId)
+					->getResource($newResource);
+				$this->addToCache($this->resourceDbTable, $resource);
+			}
+		}
+		foreach($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) {
+				$resource = $this->resourceManager->getBackend($backendId)
+					->getResource($editedResource);
+				$this->updateCache($this->resourceDbTable, $resource);
+			}
+		}
+	}
+
+	/**
+	 * 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()]);
+			}
+		}
+
+		$sortedRooms = $this->sortByNewDeletedExisting($cachedRoomIds, $remoteRoomIds);
+
+		foreach($sortedRooms['new'] as $backendId => $newRooms) {
+			foreach ($newRooms as $newRoom) {
+				$resource = $this->roomManager->getBackend($backendId)
+					->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) {
+				$resource = $this->roomManager->getBackend($backendId)
+					->getRoom($editedRoom);
+				$this->updateCache($this->roomDbTable, $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]);
+			}
+		}
+
+		return $sorted;
+	}
+
+	/**
+	 * add entry to cache that exists remotely but not yet in cache
+	 *
+	 * @param string $table
+	 * @param IResource|IRoom $remote
+	 */
+	private function addToCache($table, $remote) {
+		$query = $this->db->getQueryBuilder();
+		$query->insert($table)
+			->values([
+				'backend_id' => $query->createNamedParameter($remote->getBackend()->getBackendIdentifier()),
+				'resource_id' => $query->createNamedParameter($remote->getId()),
+				'email' => $query->createNamedParameter($remote->getEMail()),
+				'displayname' => $query->createNamedParameter($remote->getDisplayName()),
+				'group_restrictions' => $query->createNamedParameter(
+					$this->serializeGroupRestrictions(
+						$remote->getGroupRestrictions()
+					))
+			])
+			->execute();
+	}
+
+	/**
+	 * delete entry from cache that does not exist anymore remotely
+	 *
+	 * @param string $table
+	 * @param string $principalUri
+	 * @param string $backendId
+	 * @param string $resourceId
+	 */
+	private function deleteFromCache($table, $principalUri, $backendId, $resourceId) {
+		$query = $this->db->getQueryBuilder();
+		$query->delete($table)
+			->where($query->expr()->eq('backend_id', $query->createNamedParameter($backendId)))
+			->andWhere($query->expr()->eq('resource_id', $query->createNamedParameter($resourceId)))
+			->execute();
+
+		$calendar = $this->calDavBackend->getCalendarByUri($principalUri, implode('-', [$backendId, $resourceId]));
+		if ($calendar !== null) {
+			$this->calDavBackend->deleteCalendar($calendar['id']);
+		}
+	}
+
+	/**
+	 * update an existing entry in cache
+	 *
+	 * @param string $table
+	 * @param IResource|IRoom $remote
+	 */
+	private function updateCache($table, $remote) {
+		$query = $this->db->getQueryBuilder();
+		$query->update($table)
+			->set('email', $query->createNamedParameter($remote->getEMail()))
+			->set('displayname', $query->createNamedParameter($remote->getDisplayName()))
+			->set('group_restrictions', $query->createNamedParameter(
+				$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())))
+			->execute();
+	}
+
+	/**
+	 * serialize array of group restrictions to store them in database
+	 *
+	 * @param array $groups
+	 * @return string
+	 */
+	private function serializeGroupRestrictions(array $groups):string {
+		return \json_encode($groups);
+	}
+}
diff --git a/apps/dav/lib/CalDAV/CalDavBackend.php b/apps/dav/lib/CalDAV/CalDavBackend.php
index b28c8534aaa..de46dfeb244 100644
--- a/apps/dav/lib/CalDAV/CalDavBackend.php
+++ b/apps/dav/lib/CalDAV/CalDavBackend.php
@@ -76,6 +76,9 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	const PERSONAL_CALENDAR_URI = 'personal';
 	const PERSONAL_CALENDAR_NAME = 'Personal';
 
+	const RESOURCE_BOOKING_CALENDAR_URI = 'calendar';
+	const RESOURCE_BOOKING_CALENDAR_NAME = 'Calendar';
+
 	/**
 	 * We need to specify a max date, because we need to stop *somewhere*
 	 *
diff --git a/apps/dav/lib/CalDAV/CalendarRoot.php b/apps/dav/lib/CalDAV/CalendarRoot.php
index 2c1c8bb4ef2..f84e8a96780 100644
--- a/apps/dav/lib/CalDAV/CalendarRoot.php
+++ b/apps/dav/lib/CalDAV/CalendarRoot.php
@@ -27,4 +27,15 @@ class CalendarRoot extends \Sabre\CalDAV\CalendarRoot {
 	function getChildForPrincipal(array $principal) {
 		return new CalendarHome($this->caldavBackend, $principal);
 	}
+
+	function getName() {
+		if ($this->principalPrefix === 'principals/calendar-resources' ||
+			$this->principalPrefix === 'principals/calendar-rooms') {
+			$parts = explode('/', $this->principalPrefix);
+
+			return $parts[1];
+		}
+
+		return parent::getName();
+	}
 }
\ No newline at end of file
diff --git a/apps/dav/lib/CalDAV/Plugin.php b/apps/dav/lib/CalDAV/Plugin.php
index 4aa9762899f..f37d9c571a0 100644
--- a/apps/dav/lib/CalDAV/Plugin.php
+++ b/apps/dav/lib/CalDAV/Plugin.php
@@ -25,15 +25,27 @@ namespace OCA\DAV\CalDAV;
 
 class Plugin extends \Sabre\CalDAV\Plugin {
 
+	const SYSTEM_CALENDAR_ROOT = 'system-calendars';
+
 	/**
 	 * @inheritdoc
 	 */
-	function getCalendarHomeForPrincipal($principalUrl) {
+	function getCalendarHomeForPrincipal($principalUrl):string {
 
 		if (strrpos($principalUrl, 'principals/users', -strlen($principalUrl)) !== false) {
 			list(, $principalId) = \Sabre\Uri\split($principalUrl);
-			return self::CALENDAR_ROOT .'/' . $principalId;
+			return self::CALENDAR_ROOT . '/' . $principalId;
+		}
+		if (strrpos($principalUrl, 'principals/calendar-resources', -strlen($principalUrl)) !== false) {
+			list(, $principalId) = \Sabre\Uri\split($principalUrl);
+			return self::SYSTEM_CALENDAR_ROOT . '/calendar-resources/' . $principalId;
 		}
+		if (strrpos($principalUrl, 'principals/calendar-rooms', -strlen($principalUrl)) !== false) {
+			list(, $principalId) = \Sabre\Uri\split($principalUrl);
+			return self::SYSTEM_CALENDAR_ROOT . '/calendar-rooms/' . $principalId;
+		}
+
+		throw new \LogicException('This is not supposed to happen');
 	}
 
 }
diff --git a/apps/dav/lib/CalDAV/ResourceBooking/AbstractPrincipalBackend.php b/apps/dav/lib/CalDAV/ResourceBooking/AbstractPrincipalBackend.php
new file mode 100644
index 00000000000..135bbe5827e
--- /dev/null
+++ b/apps/dav/lib/CalDAV/ResourceBooking/AbstractPrincipalBackend.php
@@ -0,0 +1,361 @@
+<?php
+/**
+ * @copyright 2018, Georg Ehrke <oc.list@georgehrke.com>
+ *
+ * @author Georg Ehrke <oc.list@georgehrke.com>
+ *
+ * @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\DAV\CalDAV\ResourceBooking;
+
+use OCP\IDBConnection;
+use OCP\IGroupManager;
+use OCP\ILogger;
+use OCP\IUserSession;
+use Sabre\DAVACL\PrincipalBackend\BackendInterface;
+use Sabre\DAV\Exception;
+use \Sabre\DAV\PropPatch;
+
+abstract class AbstractPrincipalBackend implements BackendInterface {
+
+	/** @var IDBConnection */
+	private $db;
+
+	/** @var IUserSession */
+	private $userSession;
+
+	/** @var IGroupManager */
+	private $groupManager;
+
+	/** @var ILogger */
+	private $logger;
+
+	/** @var string */
+	private $principalPrefix;
+
+	/** @var string */
+	private $dbTableName;
+
+	/**
+	 * @param IDBConnection $dbConnection
+	 * @param IUserSession $userSession
+	 * @param IGroupManager $groupManager
+	 * @param ILogger $logger
+	 * @param string $principalPrefix
+	 * @param string $dbPrefix
+	 */
+	public function __construct(IDBConnection $dbConnection,
+								IUserSession $userSession,
+								IGroupManager $groupManager,
+								ILogger $logger,
+								$principalPrefix, $dbPrefix) {
+		$this->db = $dbConnection;
+		$this->userSession = $userSession;
+		$this->groupManager = $groupManager;
+		$this->logger = $logger;
+		$this->principalPrefix = $principalPrefix;
+		$this->dbTableName = 'calendar_' . $dbPrefix . '_cache';
+	}
+
+	/**
+	 * Returns a list of principals based on a prefix.
+	 *
+	 * This prefix will often contain something like 'principals'. You are only
+	 * expected to return principals that are in this base path.
+	 *
+	 * You are expected to return at least a 'uri' for every user, you can
+	 * return any additional properties if you wish so. Common properties are:
+	 *   {DAV:}displayname
+	 *
+	 * @param string $prefixPath
+	 * @return string[]
+	 */
+	public function getPrincipalsByPrefix($prefixPath) {
+		$principals = [];
+
+		if ($prefixPath === $this->principalPrefix) {
+			$query = $this->db->getQueryBuilder();
+			$query->select(['id', 'backend_id', 'resource_id', 'email', 'displayname'])
+				->from($this->dbTableName);
+			$stmt = $query->execute();
+
+			while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+				$principals[] = $this->rowToPrincipal($row);
+			}
+
+			$stmt->closeCursor();
+		}
+
+		return $principals;
+	}
+
+	/**
+	 * Returns a specific principal, specified by it's path.
+	 * The returned structure should be the exact same as from
+	 * getPrincipalsByPrefix.
+	 *
+	 * @param string $path
+	 * @return array
+	 */
+	public function getPrincipalByPath($path) {
+		if (strpos($path, $this->principalPrefix) !== 0) {
+			return null;
+		}
+		list(, $name) = \Sabre\Uri\split($path);
+
+		list($backendId, $resourceId) = explode('-',  $name, 2);
+
+		$query = $this->db->getQueryBuilder();
+		$query->select(['id', 'backend_id', 'resource_id', 'email', 'displayname'])
+			->from($this->dbTableName)
+			->where($query->expr()->eq('backend_id', $query->createNamedParameter($backendId)))
+			->andWhere($query->expr()->eq('resource_id', $query->createNamedParameter($resourceId)));
+		$stmt = $query->execute();
+		$row = $stmt->fetch(\PDO::FETCH_ASSOC);
+
+		if(!$row) {
+			return null;
+		}
+
+		return $this->rowToPrincipal($row);
+	}
+
+	/**
+	 * Returns the list of members for a group-principal
+	 *
+	 * @param string $principal
+	 * @return string[]
+	 */
+	public function getGroupMemberSet($principal) {
+		return [];
+	}
+
+	/**
+	 * Returns the list of groups a principal is a member of
+	 *
+	 * @param string $principal
+	 * @return array
+	 */
+	public function getGroupMembership($principal) {
+		return [];
+	}
+
+	/**
+	 * Updates the list of group members for a group principal.
+	 *
+	 * The principals should be passed as a list of uri's.
+	 *
+	 * @param string $principal
+	 * @param string[] $members
+	 * @throws Exception
+	 */
+	public function setGroupMemberSet($principal, array $members) {
+		throw new Exception('Setting members of the group is not supported yet');
+	}
+
+	/**
+	 * @param string $path
+	 * @param PropPatch $propPatch
+	 * @return int
+	 */
+	function updatePrincipal($path, PropPatch $propPatch) {
+		return 0;
+	}
+
+	/**
+	 * @param string $prefixPath
+	 * @param array $searchProperties
+	 * @param string $test
+	 * @return array
+	 */
+	function searchPrincipals($prefixPath, array $searchProperties, $test = 'allof') {
+		$results = [];
+		if (\count($searchProperties) === 0) {
+			return [];
+		}
+		if ($prefixPath !== $this->principalPrefix) {
+			return [];
+		}
+
+		$user = $this->userSession->getUser();
+		if (!$user) {
+			return [];
+		}
+		$usersGroups = $this->groupManager->getUserGroupIds($user);
+
+		foreach ($searchProperties as $prop => $value) {
+			switch ($prop) {
+				case '{http://sabredav.org/ns}email-address':
+					$query = $this->db->getQueryBuilder();
+					$query->select(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
+						->from($this->dbTableName)
+						->where($query->expr()->iLike('email', $query->createNamedParameter('%' . $this->db->escapeLikeParameter($value) . '%')));
+
+					$stmt = $query->execute();
+					$principals = [];
+					while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+						if (!$this->isAllowedToAccessResource($row, $usersGroups)) {
+							continue;
+						}
+						$principals[] = $this->rowToPrincipal($row)['uri'];
+					}
+					$results[] = $principals;
+
+					$stmt->closeCursor();
+					break;
+
+				case '{DAV:}displayname':
+					$query = $this->db->getQueryBuilder();
+					$query->select(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
+						->from($this->dbTableName)
+						->where($query->expr()->iLike('displayname', $query->createNamedParameter('%' . $this->db->escapeLikeParameter($value) . '%')));
+
+					$stmt = $query->execute();
+					$principals = [];
+					while($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+						if (!$this->isAllowedToAccessResource($row, $usersGroups)) {
+							continue;
+						}
+						$principals[] = $this->rowToPrincipal($row)['uri'];
+					}
+					$results[] = $principals;
+
+					$stmt->closeCursor();
+					break;
+
+				default:
+					$results[] = [];
+					break;
+			}
+		}
+
+		// results is an array of arrays, so this is not the first search result
+		// but the results of the first searchProperty
+		if (count($results) === 1) {
+			return $results[0];
+		}
+
+		switch ($test) {
+			case 'anyof':
+				return array_values(array_unique(array_merge(...$results)));
+
+			case 'allof':
+			default:
+				return array_values(array_intersect(...$results));
+		}
+	}
+
+	/**
+	 * @param string $uri
+	 * @param string $principalPrefix
+	 * @return null|string
+	 */
+	function findByUri($uri, $principalPrefix) {
+		$user = $this->userSession->getUser();
+		if (!$user) {
+			return null;
+		}
+		$usersGroups = $this->groupManager->getUserGroupIds($user);
+
+		if (strpos($uri, 'mailto:') === 0) {
+			$email = substr($uri, 7);
+			$query = $this->db->getQueryBuilder();
+			$query->select(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
+				->from($this->dbTableName)
+				->where($query->expr()->eq('email', $query->createNamedParameter($email)));
+
+			$stmt = $query->execute();
+			$row = $stmt->fetch(\PDO::FETCH_ASSOC);
+
+			if(!$row) {
+				return null;
+			}
+			if (!$this->isAllowedToAccessResource($row, $usersGroups)) {
+				return null;
+			}
+
+			return $this->rowToPrincipal($row)['uri'];
+		}
+
+		if (strpos($uri, 'principal:') === 0) {
+			$path = substr($uri, 10);
+			if (strpos($path, $this->principalPrefix) !== 0) {
+				return null;
+			}
+
+			list(, $name) = \Sabre\Uri\split($path);
+			list($backendId, $resourceId) = explode('-',  $name, 2);
+
+			$query = $this->db->getQueryBuilder();
+			$query->select(['id', 'backend_id', 'resource_id', 'email', 'displayname', 'group_restrictions'])
+				->from($this->dbTableName)
+				->where($query->expr()->eq('backend_id', $query->createNamedParameter($backendId)))
+				->andWhere($query->expr()->eq('resource_id', $query->createNamedParameter($resourceId)));
+			$stmt = $query->execute();
+			$row = $stmt->fetch(\PDO::FETCH_ASSOC);
+
+			if(!$row) {
+				return null;
+			}
+			if (!$this->isAllowedToAccessResource($row, $usersGroups)) {
+				return null;
+			}
+
+			return $this->rowToPrincipal($row)['uri'];
+		}
+
+		return null;
+	}
+
+	/**
+	 * convert database row to principal
+	 */
+	private function rowToPrincipal($row) {
+		return [
+			'uri' => $this->principalPrefix . '/' . $row['backend_id'] . '-' . $row['resource_id'],
+			'{DAV:}displayname' => $row['displayname'],
+			'{http://sabredav.org/ns}email-address' => $row['email']
+		];
+	}
+
+	/**
+	 * @param $row
+	 * @param $userGroups
+	 * @return bool
+	 */
+	private function isAllowedToAccessResource($row, $userGroups) {
+		if (!isset($row['group_restrictions']) ||
+			$row['group_restrictions'] === null ||
+			$row['group_restrictions'] === '') {
+			return true;
+		}
+
+		// group restrictions contains something, but not parsable, deny access and log warning
+		$json = json_decode($row['group_restrictions']);
+		if (!\is_array($json)) {
+			$this->logger->info('group_restrictions field could not be parsed for ' . $this->dbTableName . '::' . $row['id'] . ', denying access to resource');
+			return false;
+		}
+
+		// empty array => no group restrictions
+		if (empty($json)) {
+			return true;
+		}
+
+		return !empty(array_intersect($json, $userGroups));
+	}
+}
diff --git a/apps/dav/lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php b/apps/dav/lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php
new file mode 100644
index 00000000000..a1030376c11
--- /dev/null
+++ b/apps/dav/lib/CalDAV/ResourceBooking/ResourcePrincipalBackend.php
@@ -0,0 +1,45 @@
+<?php
+/**
+ * @copyright 2018, Georg Ehrke <oc.list@georgehrke.com>
+ *
+ * @author Georg Ehrke <oc.list@georgehrke.com>
+ *
+ * @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\DAV\CalDAV\ResourceBooking;
+
+use OCP\IDBConnection;
+use OCP\IGroupManager;
+use OCP\ILogger;
+use OCP\IUserSession;
+
+class ResourcePrincipalBackend extends AbstractPrincipalBackend {
+
+	/**
+	 * @param IDBConnection $dbConnection
+	 * @param IUserSession $userSession
+	 * @param IGroupManager $groupManager
+	 * @param ILogger $logger
+	 */
+	public function __construct(IDBConnection $dbConnection,
+								IUserSession $userSession,
+								IGroupManager $groupManager,
+								ILogger $logger) {
+		parent::__construct($dbConnection, $userSession, $groupManager, $logger,
+			'principals/calendar-resources', 'resources');
+	}
+}
diff --git a/apps/dav/lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php b/apps/dav/lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php
new file mode 100644
index 00000000000..1d22299515f
--- /dev/null
+++ b/apps/dav/lib/CalDAV/ResourceBooking/RoomPrincipalBackend.php
@@ -0,0 +1,45 @@
+<?php
+/**
+ * @copyright 2018, Georg Ehrke <oc.list@georgehrke.com>
+ *
+ * @author Georg Ehrke <oc.list@georgehrke.com>
+ *
+ * @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\DAV\CalDAV\ResourceBooking;
+
+use OCP\IDBConnection;
+use OCP\IGroupManager;
+use OCP\ILogger;
+use OCP\IUserSession;
+
+class RoomPrincipalBackend extends AbstractPrincipalBackend {
+
+	/**
+	 * @param IDBConnection $dbConnection
+	 * @param IUserSession $userSession
+	 * @param IGroupManager $groupManager
+	 * @param ILogger $logger
+	 */
+	public function __construct(IDBConnection $dbConnection,
+								IUserSession $userSession,
+								IGroupManager $groupManager,
+								ILogger $logger) {
+		parent::__construct($dbConnection, $userSession, $groupManager, $logger,
+			'principals/calendar-rooms', 'rooms');
+	}
+}
diff --git a/apps/dav/lib/CalDAV/Schedule/Plugin.php b/apps/dav/lib/CalDAV/Schedule/Plugin.php
index faf495a4de6..b3f7232c2fe 100644
--- a/apps/dav/lib/CalDAV/Schedule/Plugin.php
+++ b/apps/dav/lib/CalDAV/Schedule/Plugin.php
@@ -80,20 +80,32 @@ class Plugin extends \Sabre\CalDAV\Schedule\Plugin {
 				$principalUrl = $node->getPrincipalUrl();
 
 				$calendarHomePath = $caldavPlugin->getCalendarHomeForPrincipal($principalUrl);
-
 				if (!$calendarHomePath) {
 					return null;
 				}
 
+				if (strpos($principalUrl, 'principals/users') === 0) {
+					$uri = CalDavBackend::PERSONAL_CALENDAR_URI;
+					$displayname = CalDavBackend::PERSONAL_CALENDAR_NAME;
+				} elseif (strpos($principalUrl, 'principals/calendar-resources') === 0 ||
+						  strpos($principalUrl, 'principals/calendar-rooms') === 0) {
+					$uri = CalDavBackend::RESOURCE_BOOKING_CALENDAR_URI;
+					$displayname = CalDavBackend::RESOURCE_BOOKING_CALENDAR_NAME;
+				} else {
+					// How did we end up here?
+					// TODO - throw exception or just ignore?
+					return null;
+				}
+
 				/** @var CalendarHome $calendarHome */
 				$calendarHome = $this->server->tree->getNodeForPath($calendarHomePath);
-				if (!$calendarHome->childExists(CalDavBackend::PERSONAL_CALENDAR_URI)) {
-					$calendarHome->getCalDAVBackend()->createCalendar($principalUrl, CalDavBackend::PERSONAL_CALENDAR_URI, [
-						'{DAV:}displayname' => CalDavBackend::PERSONAL_CALENDAR_NAME,
+				if (!$calendarHome->childExists($uri)) {
+					$calendarHome->getCalDAVBackend()->createCalendar($principalUrl, $uri, [
+						'{DAV:}displayname' => $displayname,
 					]);
 				}
 
-				$result = $this->server->getPropertiesForPath($calendarHomePath . '/' . CalDavBackend::PERSONAL_CALENDAR_URI, [], 1);
+				$result = $this->server->getPropertiesForPath($calendarHomePath . '/' . $uri, [], 1);
 				if (empty($result)) {
 					return null;
 				}
diff --git a/apps/dav/lib/Migration/Version1005Date20180530124431.php b/apps/dav/lib/Migration/Version1005Date20180530124431.php
new file mode 100644
index 00000000000..ae9a40dc5b2
--- /dev/null
+++ b/apps/dav/lib/Migration/Version1005Date20180530124431.php
@@ -0,0 +1,87 @@
+<?php
+/**
+ * @copyright 2017 Georg Ehrke <oc.list@georgehrke.com>
+ *
+ * @author Georg Ehrke <oc.list@georgehrke.com>
+ *
+ * @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\DAV\Migration;
+
+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 Version1005Date20180530124431 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();
+
+		$types = ['resources', 'rooms'];
+		foreach($types as $type) {
+			if (!$schema->hasTable('calendar_' . $type . '_cache')) {
+				$table = $schema->createTable('calendar_' . $type . '_cache');
+
+				$table->addColumn('id', Type::BIGINT, [
+					'autoincrement' => true,
+					'notnull' => true,
+					'length' => 11,
+					'unsigned' => true,
+				]);
+				$table->addColumn('backend_id', Type::STRING, [
+					'notnull' => false,
+					'length' => 64,
+				]);
+				$table->addColumn('resource_id', Type::STRING, [
+					'notnull' => false,
+					'length' => 64,
+				]);
+				$table->addColumn('email', Type::STRING, [
+					'notnull' => false,
+					'length' => 255,
+				]);
+				$table->addColumn('displayname', Type::STRING, [
+					'notnull' => false,
+					'length' => 255,
+				]);
+				$table->addColumn('group_restrictions', Type::STRING, [
+					'notnull' => false,
+					'length' => 4000,
+				]);
+
+				$table->setPrimaryKey(['id'], 'calendar_' . $type . '_cache_id_idx');
+				$table->addIndex(['backend_id', 'resource_id'], 'calendar_' . $type . '_cache_backendresource_idx');
+				$table->addIndex(['email'], 'calendar_' . $type . '_cache_email_idx');
+				$table->addIndex(['displayname'], 'calendar_' . $type . '_cache_displayname_idx');
+			}
+		}
+
+		return $schema;
+	}
+}
diff --git a/apps/dav/lib/RootCollection.php b/apps/dav/lib/RootCollection.php
index b9f381b4b92..9a3261c388c 100644
--- a/apps/dav/lib/RootCollection.php
+++ b/apps/dav/lib/RootCollection.php
@@ -27,6 +27,8 @@ namespace OCA\DAV;
 use OCA\DAV\CalDAV\CalDavBackend;
 use OCA\DAV\CalDAV\CalendarRoot;
 use OCA\DAV\CalDAV\PublicCalendarRoot;
+use OCA\DAV\CalDAV\ResourceBooking\ResourcePrincipalBackend;
+use OCA\DAV\CalDAV\ResourceBooking\RoomPrincipalBackend;
 use OCA\DAV\CardDAV\AddressBookRoot;
 use OCA\DAV\CardDAV\CardDavBackend;
 use OCA\DAV\Connector\Sabre\Principal;
@@ -43,6 +45,7 @@ class RootCollection extends SimpleCollection {
 		$random = \OC::$server->getSecureRandom();
 		$logger = \OC::$server->getLogger();
 		$userManager = \OC::$server->getUserManager();
+		$userSession = \OC::$server->getUserSession();
 		$groupManager = \OC::$server->getGroupManager();
 		$shareManager = \OC::$server->getShareManager();
 		$db = \OC::$server->getDatabaseConnection();
@@ -55,6 +58,8 @@ class RootCollection extends SimpleCollection {
 			$config
 		);
 		$groupPrincipalBackend = new GroupPrincipalBackend($groupManager);
+		$calendarResourcePrincipalBackend = new ResourcePrincipalBackend($db, $userSession, $groupManager, $logger);
+		$calendarRoomPrincipalBackend = new RoomPrincipalBackend($db, $userSession, $groupManager, $logger);
 		// as soon as debug mode is enabled we allow listing of principals
 		$disableListing = !$config->getSystemValue('debug', false);
 
@@ -65,11 +70,25 @@ class RootCollection extends SimpleCollection {
 		$groupPrincipals->disableListing = $disableListing;
 		$systemPrincipals = new Collection(new SystemPrincipalBackend(), 'principals/system');
 		$systemPrincipals->disableListing = $disableListing;
+		$calendarResourcePrincipals = new Collection($calendarResourcePrincipalBackend, 'principals/calendar-resources');
+		$calendarResourcePrincipals->disableListing = $disableListing;
+		$calendarRoomPrincipals = new Collection($calendarRoomPrincipalBackend, 'principals/calendar-rooms');
+		$calendarRoomPrincipals->disableListing = $disableListing;
+
+
 		$filesCollection = new Files\RootCollection($userPrincipalBackend, 'principals/users');
 		$filesCollection->disableListing = $disableListing;
 		$caldavBackend = new CalDavBackend($db, $userPrincipalBackend, $userManager, $groupManager, $random, $logger, $dispatcher);
-		$calendarRoot = new CalendarRoot($userPrincipalBackend, $caldavBackend, 'principals/users');
-		$calendarRoot->disableListing = $disableListing;
+		$userCalendarRoot = new CalendarRoot($userPrincipalBackend, $caldavBackend, 'principals/users');
+		$userCalendarRoot->disableListing = $disableListing;
+
+		$resourceCalendarCaldavBackend = new CalDavBackend($db, $userPrincipalBackend, $userManager, $groupManager, $random, $logger, $dispatcher);
+		$resourceCalendarRoot = new CalendarRoot($calendarResourcePrincipalBackend, $caldavBackend, 'principals/calendar-resources');
+		$resourceCalendarRoot->disableListing = $disableListing;
+		$roomCalendarCaldavBackend = new CalDavBackend($db, $userPrincipalBackend, $userManager, $groupManager, $random, $logger, $dispatcher);
+		$roomCalendarRoot = new CalendarRoot($calendarRoomPrincipalBackend, $roomCalendarCaldavBackend, 'principals/calendar-rooms');
+		$roomCalendarRoot->disableListing = $disableListing;
+
 		$publicCalendarRoot = new PublicCalendarRoot($caldavBackend, $l10n, $config);
 		$publicCalendarRoot->disableListing = $disableListing;
 
@@ -111,9 +130,15 @@ class RootCollection extends SimpleCollection {
 				new SimpleCollection('principals', [
 						$userPrincipals,
 						$groupPrincipals,
-						$systemPrincipals]),
+						$systemPrincipals,
+						$calendarResourcePrincipals,
+						$calendarRoomPrincipals]),
 				$filesCollection,
-				$calendarRoot,
+				$userCalendarRoot,
+				new SimpleCollection('system-calendars', [
+					$resourceCalendarRoot,
+					$roomCalendarRoot,
+				]),
 				$publicCalendarRoot,
 				new SimpleCollection('addressbooks', [
 						$usersAddressBookRoot,
diff --git a/apps/dav/lib/Server.php b/apps/dav/lib/Server.php
index a401fb57045..231ab913195 100644
--- a/apps/dav/lib/Server.php
+++ b/apps/dav/lib/Server.php
@@ -132,13 +132,15 @@ class Server {
 		// acl
 		$acl = new DavAclPlugin();
 		$acl->principalCollectionSet = [
-			'principals/users', 'principals/groups'
+			'principals/users', 'principals/groups',
+			'principals/calendar-resources',
+			'principals/calendar-rooms',
 		];
 		$acl->defaultUsernamePath = 'principals/users';
 		$this->server->addPlugin($acl);
 
 		// calendar plugins
-		if ($this->requestIsForSubtree(['calendars', 'public-calendars', 'principals'])) {
+		if ($this->requestIsForSubtree(['calendars', 'public-calendars', 'system-calendars', 'principals'])) {
 			$this->server->addPlugin(new \OCA\DAV\CalDAV\Plugin());
 			$this->server->addPlugin(new \Sabre\CalDAV\ICSExportPlugin());
 			$this->server->addPlugin(new \OCA\DAV\CalDAV\Schedule\Plugin());