Use the event dispatcher

Signed-off-by: Joas Schilling <coding@schilljs.com>

8 files changed, 189 insertions, 177 deletions

diff --git a/apps/dav/appinfo/v1/caldav.php b/apps/dav/appinfo/v1/caldav.php
index ecd6a171235..9f12a92f4cd 100644
--- a/apps/dav/appinfo/v1/caldav.php
+++ b/apps/dav/appinfo/v1/caldav.php
@@ -48,10 +48,8 @@ $principalBackend = new Principal(
 $db = \OC::$server->getDatabaseConnection();
 $userManager = \OC::$server->getUserManager();
 $random = \OC::$server->getSecureRandom();
-$groupManager = \OC::$server->getGroupManager();
-$activityManager = \OC::$server->getActivityManager();
-$userSession = \OC::$server->getUserSession();
-$calDavBackend = new CalDavBackend($db, $principalBackend, $userManager, $groupManager, $random, $activityManager, $userSession);
+$dispatcher = \OC::$server->getEventDispatcher();
+$calDavBackend = new CalDavBackend($db, $principalBackend, $userManager, $random, $dispatcher);
 
 $debugging = \OC::$server->getConfig()->getSystemValue('debug', false);
 
diff --git a/apps/dav/lib/AppInfo/Application.php b/apps/dav/lib/AppInfo/Application.php
index 32483e8fd8e..c777f5e5a35 100644
--- a/apps/dav/lib/AppInfo/Application.php
+++ b/apps/dav/lib/AppInfo/Application.php
@@ -24,6 +24,7 @@
  */
 namespace OCA\DAV\AppInfo;
 
+use OCA\DAV\CalDAV\Activity\Backend;
 use OCA\DAV\CalDAV\Activity\Extension;
 use OCA\DAV\CalDAV\BirthdayService;
 use OCA\DAV\Capabilities;
@@ -90,6 +91,62 @@ class Application extends App {
 			}
 		});
 
+		$dispatcher->addListener('\OCA\DAV\CalDAV\CalDavBackend::createCalendar', function(GenericEvent $event) {
+			/** @var Backend $backend */
+			$backend = $this->getContainer()->query(Backend::class);
+			$backend->onCalendarAdd(
+				$event->getArgument('calendarData')
+			);
+		});
+		$dispatcher->addListener('\OCA\DAV\CalDAV\CalDavBackend::updateCalendar', function(GenericEvent $event) {
+			/** @var Backend $backend */
+			$backend = $this->getContainer()->query(Backend::class);
+			$backend->onCalendarUpdate(
+				$event->getArgument('calendarData'),
+				$event->getArgument('shares'),
+				$event->getArgument('propertyMutations')
+			);
+		});
+		$dispatcher->addListener('\OCA\DAV\CalDAV\CalDavBackend::deleteCalendar', function(GenericEvent $event) {
+			/** @var Backend $backend */
+			$backend = $this->getContainer()->query(Backend::class);
+			$backend->onCalendarDelete(
+				$event->getArgument('calendarData'),
+				$event->getArgument('shares')
+			);
+		});
+		$dispatcher->addListener('\OCA\DAV\CalDAV\CalDavBackend::updateShares', function(GenericEvent $event) {
+			/** @var Backend $backend */
+			$backend = $this->getContainer()->query(Backend::class);
+			$backend->onCalendarUpdateShares(
+				$event->getArgument('calendarData'),
+				$event->getArgument('shares'),
+				$event->getArgument('add'),
+				$event->getArgument('remove')
+			);
+		});
+
+		$listener = function(GenericEvent $event, $eventName) {
+			/** @var Backend $backend */
+			$backend = $this->getContainer()->query(Backend::class);
+
+			$subject = Extension::SUBJECT_OBJECT_ADD;
+			if ($eventName === '\OCA\DAV\CalDAV\CalDavBackend::updateCalendarObject') {
+				$subject = Extension::SUBJECT_OBJECT_UPDATE;
+			} else if ($eventName === '\OCA\DAV\CalDAV\CalDavBackend::deleteCalendarObject') {
+				$subject = Extension::SUBJECT_OBJECT_DELETE;
+			}
+			$backend->onTouchCalendarObject(
+				$subject,
+				$event->getArgument('calendarData'),
+				$event->getArgument('shares'),
+				$event->getArgument('objectData')
+			);
+		};
+		$dispatcher->addListener('\OCA\DAV\CalDAV\CalDavBackend::createCalendarObject', $listener);
+		$dispatcher->addListener('\OCA\DAV\CalDAV\CalDavBackend::updateCalendarObject', $listener);
+		$dispatcher->addListener('\OCA\DAV\CalDAV\CalDavBackend::deleteCalendarObject', $listener);
+
 		$aM = $this->getContainer()->getServer()->getActivityManager();
 		$aM->registerExtension(function() {
 			return $this->getContainer()->query(Extension::class);
diff --git a/apps/dav/lib/CalDAV/Activity/Backend.php b/apps/dav/lib/CalDAV/Activity/Backend.php
index 1c1637cd562..6cf09f6de46 100644
--- a/apps/dav/lib/CalDAV/Activity/Backend.php
+++ b/apps/dav/lib/CalDAV/Activity/Backend.php
@@ -22,8 +22,6 @@
 namespace OCA\DAV\CalDAV\Activity;
 
 
-use OCA\DAV\CalDAV\CalDavBackend;
-use OCA\DAV\CalDAV\Calendar;
 use OCP\Activity\IEvent;
 use OCP\Activity\IManager as IActivityManager;
 use OCP\IGroup;
@@ -39,9 +37,6 @@ use Sabre\VObject\Reader;
  */
 class Backend {
 
-	/** @var CalDavBackend */
-	protected  $calDavBackend;
-
 	/** @var IActivityManager */
 	protected $activityManager;
 
@@ -52,13 +47,11 @@ class Backend {
 	protected $userSession;
 
 	/**
-	 * @param CalDavBackend $calDavBackend
 	 * @param IActivityManager $activityManager
 	 * @param IGroupManager $groupManager
 	 * @param IUserSession $userSession
 	 */
-	public function __construct(CalDavBackend $calDavBackend, IActivityManager $activityManager, IGroupManager $groupManager, IUserSession $userSession) {
-		$this->calDavBackend = $calDavBackend;
+	public function __construct(IActivityManager $activityManager, IGroupManager $groupManager, IUserSession $userSession) {
 		$this->activityManager = $activityManager;
 		$this->groupManager = $groupManager;
 		$this->userSession = $userSession;
@@ -67,46 +60,47 @@ class Backend {
 	/**
 	 * Creates activities when a calendar was creates
 	 *
-	 * @param int $calendarId
-	 * @param array $properties
+	 * @param array $calendarData
 	 */
-	public function addCalendar($calendarId, array $properties) {
-		$this->triggerCalendarActivity(Extension::SUBJECT_ADD, $calendarId, $properties);
+	public function onCalendarAdd(array $calendarData) {
+		$this->triggerCalendarActivity(Extension::SUBJECT_ADD, $calendarData);
 	}
 
 	/**
 	 * Creates activities when a calendar was updated
 	 *
-	 * @param int $calendarId
+	 * @param array $calendarData
+	 * @param array $shares
 	 * @param array $properties
 	 */
-	public function updateCalendar($calendarId, array $properties) {
-		$this->triggerCalendarActivity(Extension::SUBJECT_UPDATE, $calendarId, $properties);
+	public function onCalendarUpdate(array $calendarData, array $shares, array $properties) {
+		$this->triggerCalendarActivity(Extension::SUBJECT_UPDATE, $calendarData, $shares, $properties);
 	}
 
 	/**
 	 * Creates activities when a calendar was deleted
 	 *
-	 * @param int $calendarId
+	 * @param array $calendarData
+	 * @param array $shares
 	 */
-	public function deleteCalendar($calendarId) {
-		$this->triggerCalendarActivity(Extension::SUBJECT_DELETE, $calendarId);
+	public function onCalendarDelete(array $calendarData, array $shares) {
+		$this->triggerCalendarActivity(Extension::SUBJECT_DELETE, $calendarData, $shares);
 	}
 
 	/**
 	 * Creates activities for all related users when a calendar was touched
 	 *
 	 * @param string $action
-	 * @param int $calendarId
+	 * @param array $calendarData
+	 * @param array $shares
 	 * @param array $changedProperties
 	 */
-	protected function triggerCalendarActivity($action, $calendarId, array $changedProperties = []) {
-		$properties = $this->calDavBackend->getCalendarById($calendarId);
-		if (!isset($properties['principaluri'])) {
+	protected function triggerCalendarActivity($action, array $calendarData, array $shares = [], array $changedProperties = []) {
+		if (!isset($calendarData['principaluri'])) {
 			return;
 		}
 
-		$principal = explode('/', $properties['principaluri']);
+		$principal = explode('/', $calendarData['principaluri']);
 		$owner = $principal[2];
 
 		$currentUser = $this->userSession->getUser();
@@ -118,7 +112,7 @@ class Backend {
 
 		$event = $this->activityManager->generateEvent();
 		$event->setApp('dav')
-			->setObject(Extension::CALENDAR, $calendarId)
+			->setObject(Extension::CALENDAR, $calendarData['id'])
 			->setType(Extension::CALENDAR)
 			->setAuthor($currentUser);
 
@@ -127,10 +121,10 @@ class Backend {
 			'{http://apple.com/ns/ical/}calendar-color'
 		], array_keys($changedProperties));
 
-		if ($action === Extension::SUBJECT_UPDATE && empty($changedVisibleInformation)) {
+		if (empty($shares) || ($action === Extension::SUBJECT_UPDATE && empty($changedVisibleInformation))) {
 			$users = [$owner];
 		} else {
-			$users = $this->getUsersForCalendar($calendarId);
+			$users = $this->getUsersForShares($shares);
 			$users[] = $owner;
 		}
 
@@ -140,7 +134,7 @@ class Backend {
 					$user === $currentUser ? $action . '_self' : $action,
 					[
 						$currentUser,
-						$properties['{DAV:}displayname'],
+						$calendarData['{DAV:}displayname'],
 					]
 				);
 			$this->activityManager->publish($event);
@@ -150,16 +144,13 @@ class Backend {
 	/**
 	 * Creates activities for all related users when a calendar was (un-)shared
 	 *
-	 * @param Calendar $calendar
+	 * @param array $calendarData
+	 * @param array $shares
 	 * @param array $add
 	 * @param array $remove
 	 */
-	public function updateCalendarShares(Calendar $calendar, array $add, array $remove) {
-		$calendarId = $calendar->getResourceId();
-		$shares = $this->calDavBackend->getShares($calendarId);
-
-		$properties = $this->calDavBackend->getCalendarById($calendarId);
-		$principal = explode('/', $properties['principaluri']);
+	public function onCalendarUpdateShares(array $calendarData, array $shares, array $add, array $remove) {
+		$principal = explode('/', $calendarData['principaluri']);
 		$owner = $principal[2];
 
 		$currentUser = $this->userSession->getUser();
@@ -171,7 +162,7 @@ class Backend {
 
 		$event = $this->activityManager->generateEvent();
 		$event->setApp('dav')
-			->setObject(Extension::CALENDAR, $calendarId)
+			->setObject(Extension::CALENDAR, $calendarData['id'])
 			->setType(Extension::CALENDAR)
 			->setAuthor($currentUser);
 
@@ -187,7 +178,7 @@ class Backend {
 				$this->triggerActivityUser(
 					$principal[2],
 					$event,
-					$properties,
+					$calendarData,
 					Extension::SUBJECT_UNSHARE_USER,
 					Extension::SUBJECT_DELETE . '_self'
 				);
@@ -195,7 +186,7 @@ class Backend {
 				if ($owner !== $principal[2]) {
 					$parameters = [
 						$principal[2],
-						$properties['{DAV:}displayname'],
+						$calendarData['{DAV:}displayname'],
 					];
 
 					if ($owner === $event->getAuthor()) {
@@ -216,11 +207,11 @@ class Backend {
 					$this->activityManager->publish($event);
 				}
 			} else if ($principal[1] === 'groups') {
-				$this->triggerActivityGroup($principal[2], $event, $properties, Extension::SUBJECT_UNSHARE_USER);
+				$this->triggerActivityGroup($principal[2], $event, $calendarData, Extension::SUBJECT_UNSHARE_USER);
 
 				$parameters = [
 					$principal[2],
-					$properties['{DAV:}displayname'],
+					$calendarData['{DAV:}displayname'],
 				];
 
 				if ($owner === $event->getAuthor()) {
@@ -253,12 +244,12 @@ class Backend {
 			$principal = explode('/', $parts[1]);
 
 			if ($principal[1] === 'users') {
-				$this->triggerActivityUser($principal[2], $event, $properties, Extension::SUBJECT_SHARE_USER);
+				$this->triggerActivityUser($principal[2], $event, $calendarData, Extension::SUBJECT_SHARE_USER);
 
 				if ($owner !== $principal[2]) {
 					$parameters = [
 						$principal[2],
-						$properties['{DAV:}displayname'],
+						$calendarData['{DAV:}displayname'],
 					];
 
 					if ($owner === $event->getAuthor()) {
@@ -277,11 +268,11 @@ class Backend {
 					$this->activityManager->publish($event);
 				}
 			} else if ($principal[1] === 'groups') {
-				$this->triggerActivityGroup($principal[2], $event, $properties, Extension::SUBJECT_SHARE_USER);
+				$this->triggerActivityGroup($principal[2], $event, $calendarData, Extension::SUBJECT_SHARE_USER);
 
 				$parameters = [
 					$principal[2],
-					$properties['{DAV:}displayname'],
+					$calendarData['{DAV:}displayname'],
 				];
 
 				if ($owner === $event->getAuthor()) {
@@ -363,49 +354,19 @@ class Backend {
 	}
 
 	/**
-	 * Creates activities when a calendar object was created
-	 *
-	 * @param int $calendarId
-	 * @param string $objectUri
-	 */
-	public function addCalendarObject($calendarId, $objectUri) {
-		$this->triggerCalendarObjectActivity(Extension::SUBJECT_OBJECT_ADD, $calendarId, $objectUri);
-	}
-
-	/**
-	 * Creates activities when a calendar object was updated
-	 *
-	 * @param int $calendarId
-	 * @param string $objectUri
-	 */
-	public function updateCalendarObject($calendarId, $objectUri) {
-		$this->triggerCalendarObjectActivity(Extension::SUBJECT_OBJECT_UPDATE, $calendarId, $objectUri);
-	}
-
-	/**
-	 * Creates activities when a calendar object was deleted
-	 *
-	 * @param int $calendarId
-	 * @param string $objectUri
-	 */
-	public function deleteCalendarObject($calendarId, $objectUri) {
-		$this->triggerCalendarObjectActivity(Extension::SUBJECT_OBJECT_DELETE, $calendarId, $objectUri);
-	}
-
-	/**
-	 * Creates activities for all related users when a calendar was touched
+	 * Creates activities when a calendar object was created/updated/deleted
 	 *
 	 * @param string $action
-	 * @param int $calendarId
-	 * @param string $objectUri
+	 * @param array $calendarData
+	 * @param array $shares
+	 * @param array $objectData
 	 */
-	protected function triggerCalendarObjectActivity($action, $calendarId, $objectUri) {
-		$properties = $this->calDavBackend->getCalendarById($calendarId);
-		if (!isset($properties['principaluri'])) {
+	public function onTouchCalendarObject($action, array $calendarData, array $shares, array $objectData) {
+		if (!isset($calendarData['principaluri'])) {
 			return;
 		}
 
-		$principal = explode('/', $properties['principaluri']);
+		$principal = explode('/', $calendarData['principaluri']);
 		$owner = $principal[2];
 
 		$currentUser = $this->userSession->getUser();
@@ -415,7 +376,7 @@ class Backend {
 			$currentUser = $owner;
 		}
 
-		$object = $this->getObjectNameAndType($calendarId, $objectUri);
+		$object = $this->getObjectNameAndType($objectData);
 		$action = $action . '_' . $object['type'];
 
 		if ($object['type'] === 'todo' && strpos($action, Extension::SUBJECT_OBJECT_UPDATE) === 0 && $object['status'] === 'COMPLETED') {
@@ -426,11 +387,11 @@ class Backend {
 
 		$event = $this->activityManager->generateEvent();
 		$event->setApp('dav')
-			->setObject(Extension::CALENDAR, $calendarId)
+			->setObject(Extension::CALENDAR, $calendarData['id'])
 			->setType($object['type'] === 'event' ? Extension::CALENDAR_EVENT : Extension::CALENDAR_TODO)
 			->setAuthor($currentUser);
 
-		$users = $this->getUsersForCalendar($calendarId);
+		$users = $this->getUsersForShares($shares);
 		$users[] = $owner;
 
 		foreach ($users as $user) {
@@ -439,7 +400,7 @@ class Backend {
 					$user === $currentUser ? $action . '_self' : $action,
 					[
 						$currentUser,
-						$properties['{DAV:}displayname'],
+						$calendarData['{DAV:}displayname'],
 						$object['name'],
 					]
 				);
@@ -448,14 +409,11 @@ class Backend {
 	}
 
 	/**
-	 * @param int $calendarId
-	 * @param string $objectUri
+	 * @param array $objectData
 	 * @return string[]|bool
 	 */
-	protected function getObjectNameAndType($calendarId, $objectUri) {
-		$data = $this->calDavBackend->getCalendarObject($calendarId, $objectUri);
-
-		$vObject = Reader::read($data['calendardata']);
+	protected function getObjectNameAndType(array $objectData) {
+		$vObject = Reader::read($objectData['calendardata']);
 		$component = $componentType = null;
 		foreach($vObject->getComponents() as $component) {
 			if (in_array($component->name, ['VEVENT', 'VTODO'])) {
@@ -478,12 +436,11 @@ class Backend {
 	/**
 	 * Get all users that have access to a given calendar
 	 *
-	 * @param int $calendarId
+	 * @param array $shares
 	 * @return string[]
 	 */
-	protected function getUsersForCalendar($calendarId) {
+	protected function getUsersForShares(array $shares) {
 		$users = $groups = [];
-		$shares = $this->calDavBackend->getShares($calendarId);
 		foreach ($shares as $share) {
 			$prinical = explode('/', $share['{http://owncloud.org/ns}principal']);
 			if ($prinical[1] === 'users') {
diff --git a/apps/dav/lib/CalDAV/CalDavBackend.php b/apps/dav/lib/CalDAV/CalDavBackend.php
index 660114e462a..fb608c2009d 100644
--- a/apps/dav/lib/CalDAV/CalDavBackend.php
+++ b/apps/dav/lib/CalDAV/CalDavBackend.php
@@ -26,16 +26,12 @@
 namespace OCA\DAV\CalDAV;
 
 use OCA\DAV\DAV\Sharing\IShareable;
-use OCA\DAV\CalDAV\Activity\Backend as ActivityBackend;
-use OCP\Activity\IManager as IActivityManager;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCA\DAV\Connector\Sabre\Principal;
 use OCA\DAV\DAV\Sharing\Backend;
 use OCP\IDBConnection;
-use OCP\IGroupManager;
 use OCP\IUser;
 use OCP\IUserManager;
-use OCP\IUserSession;
 use OCP\Security\ISecureRandom;
 use Sabre\CalDAV\Backend\AbstractBackend;
 use Sabre\CalDAV\Backend\SchedulingSupport;
@@ -52,6 +48,8 @@ use Sabre\HTTP\URLUtil;
 use Sabre\VObject\DateTimeParser;
 use Sabre\VObject\Reader;
 use Sabre\VObject\Recur\EventIterator;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Symfony\Component\EventDispatcher\GenericEvent;
 
 /**
  * Class CalDavBackend
@@ -131,8 +129,8 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	/** @var ISecureRandom */
 	private $random;
 
-	/** @var ActivityBackend */
-	private $activityBackend;
+	/** @var EventDispatcherInterface */
+	private $dispatcher;
 
 	/**
 	 * CalDavBackend constructor.
@@ -140,25 +138,20 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	 * @param IDBConnection $db
 	 * @param Principal $principalBackend
 	 * @param IUserManager $userManager
-	 * @param IGroupManager $groupManager
 	 * @param ISecureRandom $random
-	 * @param IActivityManager $activityManager
-	 * @param IUserSession $userSession
+	 * @param EventDispatcherInterface $dispatcher
 	 */
 	public function __construct(IDBConnection $db,
 								Principal $principalBackend,
 								IUserManager $userManager,
-								IGroupManager $groupManager,
 								ISecureRandom $random,
-								IActivityManager $activityManager,
-								IUserSession $userSession) {
+								EventDispatcherInterface $dispatcher) {
 		$this->db = $db;
 		$this->principalBackend = $principalBackend;
 		$this->userManager = $userManager;
-		$this->userManager = $groupManager;
 		$this->sharingBackend = new Backend($this->db, $principalBackend, 'calendar');
-		$this->activityBackend = new ActivityBackend($this, $activityManager, $groupManager, $userSession);
 		$this->random = $random;
+		$this->dispatcher = $dispatcher;
 	}
 
 	/**
@@ -623,7 +616,12 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 		$query->execute();
 		$calendarId = $query->getLastInsertId();
 
-		$this->activityBackend->addCalendar($calendarId, $values);
+		$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::createCalendar', new GenericEvent(
+			'\OCA\DAV\CalDAV\CalDavBackend::createCalendar',
+			[
+				'calendarId' => $calendarId,
+				'calendarData' => $this->getCalendarById($calendarId),
+		]));
 
 		return $calendarId;
 	}
@@ -673,7 +671,14 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 
 			$this->addChange($calendarId, "", 2);
 
-			$this->activityBackend->updateCalendar($calendarId, $mutations);
+			$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::updateCalendar', new GenericEvent(
+				'\OCA\DAV\CalDAV\CalDavBackend::updateCalendar',
+				[
+					'calendarId' => $calendarId,
+					'calendarData' => $this->getCalendarById($calendarId),
+					'shares' => $this->getShares($calendarId),
+					'propertyMutations' => $mutations,
+			]));
 
 			return true;
 		});
@@ -686,7 +691,13 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	 * @return void
 	 */
 	function deleteCalendar($calendarId) {
-		$this->activityBackend->deleteCalendar($calendarId);
+		$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::deleteCalendar', new GenericEvent(
+			'\OCA\DAV\CalDAV\CalDavBackend::deleteCalendar',
+			[
+				'calendarId' => $calendarId,
+				'calendarData' => $this->getCalendarById($calendarId),
+				'shares' => $this->getShares($calendarId),
+		]));
 
 		$stmt = $this->db->prepare('DELETE FROM `*PREFIX*calendarobjects` WHERE `calendarid` = ?');
 		$stmt->execute([$calendarId]);
@@ -892,7 +903,15 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 			])
 			->execute();
 
-		$this->activityBackend->addCalendarObject($calendarId, $objectUri);
+		$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::createCalendarObject', new GenericEvent(
+			'\OCA\DAV\CalDAV\CalDavBackend::createCalendarObject',
+			[
+				'calendarId' => $calendarId,
+				'calendarData' => $this->getCalendarById($calendarId),
+				'shares' => $this->getShares($calendarId),
+				'objectData' => $this->getCalendarObject($calendarId, $objectUri),
+			]
+		));
 		$this->addChange($calendarId, $objectUri, 1);
 
 		return '"' . $extraData['etag'] . '"';
@@ -934,7 +953,18 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 			->andWhere($query->expr()->eq('uri', $query->createNamedParameter($objectUri)))
 			->execute();
 
-		$this->activityBackend->updateCalendarObject($calendarId, $objectUri);
+		$data = $this->getCalendarObject($calendarId, $objectUri);
+		if (is_array($data)) {
+			$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::updateCalendarObject', new GenericEvent(
+				'\OCA\DAV\CalDAV\CalDavBackend::updateCalendarObject',
+				[
+					'calendarId' => $calendarId,
+					'calendarData' => $this->getCalendarById($calendarId),
+					'shares' => $this->getShares($calendarId),
+					'objectData' => $data,
+				]
+			));
+		}
 		$this->addChange($calendarId, $objectUri, 2);
 
 		return '"' . $extraData['etag'] . '"';
@@ -967,7 +997,18 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	 * @return void
 	 */
 	function deleteCalendarObject($calendarId, $objectUri) {
-		$this->activityBackend->deleteCalendarObject($calendarId, $objectUri);
+		$data = $this->getCalendarObject($calendarId, $objectUri);
+		if (is_array($data)) {
+			$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::deleteCalendarObject', new GenericEvent(
+				'\OCA\DAV\CalDAV\CalDavBackend::deleteCalendarObject',
+				[
+					'calendarId' => $calendarId,
+					'calendarData' => $this->getCalendarById($calendarId),
+					'shares' => $this->getShares($calendarId),
+					'objectData' => $data,
+				]
+			));
+		}
 
 		$stmt = $this->db->prepare('DELETE FROM `*PREFIX*calendarobjects` WHERE `calendarid` = ? AND `uri` = ?');
 		$stmt->execute([$calendarId, $objectUri]);
@@ -1668,8 +1709,16 @@ class CalDavBackend extends AbstractBackend implements SyncSupport, Subscription
 	 * @param array $remove
 	 */
 	public function updateShares($shareable, $add, $remove) {
-		/** @var Calendar $shareable */
-		$this->activityBackend->updateCalendarShares($shareable, $add, $remove);
+		$calendarId = $shareable->getResourceId();
+		$this->dispatcher->dispatch('\OCA\DAV\CalDAV\CalDavBackend::updateShares', new GenericEvent(
+			'\OCA\DAV\CalDAV\CalDavBackend::updateShares',
+			[
+				'calendarId' => $calendarId,
+				'calendarData' => $this->getCalendarById($calendarId),
+				'shares' => $this->getShares($calendarId),
+				'add' => $add,
+				'remove' => $remove,
+			]));
 		$this->sharingBackend->updateShares($shareable, $add, $remove);
 	}
 
diff --git a/apps/dav/lib/Command/CreateCalendar.php b/apps/dav/lib/Command/CreateCalendar.php
index 6fea6082443..24990352fab 100644
--- a/apps/dav/lib/Command/CreateCalendar.php
+++ b/apps/dav/lib/Command/CreateCalendar.php
@@ -76,11 +76,10 @@ class CreateCalendar extends Command {
 			$this->groupManager
 		);
 		$random = \OC::$server->getSecureRandom();
-		$activityManager = \OC::$server->getActivityManager();
-		$userSession = \OC::$server->getUserSession();
+		$dispatcher = \OC::$server->getEventDispatcher();
 
 		$name = $input->getArgument('name');
-		$caldav = new CalDavBackend($this->dbConnection, $principalBackend, $this->userManager, $this->groupManager, $random, $activityManager, $userSession);
+		$caldav = new CalDavBackend($this->dbConnection, $principalBackend, $this->userManager, $random, $dispatcher);
 		$caldav->createCalendar("principals/users/$user", $name, []);
 	}
 }
diff --git a/apps/dav/lib/RootCollection.php b/apps/dav/lib/RootCollection.php
index 38b4ec795d2..478f0929c20 100644
--- a/apps/dav/lib/RootCollection.php
+++ b/apps/dav/lib/RootCollection.php
@@ -41,9 +41,6 @@ class RootCollection extends SimpleCollection {
 		$config = \OC::$server->getConfig();
 		$random = \OC::$server->getSecureRandom();
 		$userManager = \OC::$server->getUserManager();
-		$groupManager = \OC::$server->getGroupManager();
-		$activityManager = \OC::$server->getActivityManager();
-		$userSession = \OC::$server->getUserSession();
 		$db = \OC::$server->getDatabaseConnection();
 		$dispatcher = \OC::$server->getEventDispatcher();
 		$userPrincipalBackend = new Principal(
@@ -65,7 +62,7 @@ class RootCollection extends SimpleCollection {
 		$systemPrincipals->disableListing = $disableListing;
 		$filesCollection = new Files\RootCollection($userPrincipalBackend, 'principals/users');
 		$filesCollection->disableListing = $disableListing;
-		$caldavBackend = new CalDavBackend($db, $userPrincipalBackend, $userManager, $groupManager, $random, $activityManager, $userSession);
+		$caldavBackend = new CalDavBackend($db, $userPrincipalBackend, $userManager, $random, $dispatcher);
 		$calendarRoot = new CalendarRoot($userPrincipalBackend, $caldavBackend, 'principals/users');
 		$calendarRoot->disableListing = $disableListing;
 		$publicCalendarRoot = new PublicCalendarRoot($caldavBackend);
diff --git a/apps/dav/tests/unit/CalDAV/AbstractCalDavBackendTest.php b/apps/dav/tests/unit/CalDAV/AbstractCalDavBackendTest.php
index a674c65c286..7d2e033e0b1 100644
--- a/apps/dav/tests/unit/CalDAV/AbstractCalDavBackendTest.php
+++ b/apps/dav/tests/unit/CalDAV/AbstractCalDavBackendTest.php
@@ -22,15 +22,12 @@
 
 namespace OCA\DAV\Tests\unit\CalDAV;
 
-use OCA\DAV\CalDAV\Activity\Backend as ActivityBackend;
 use OCA\DAV\CalDAV\CalDavBackend;
 use OCA\DAV\Connector\Sabre\Principal;
-use OCP\Activity\IManager as IActivityManager;
-use OCP\IGroupManager;
 use OCP\IUserManager;
-use OCP\IUserSession;
 use OCP\Security\ISecureRandom;
 use Sabre\CalDAV\Xml\Property\SupportedCalendarComponentSet;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 use Test\TestCase;
 
 /**
@@ -49,8 +46,6 @@ abstract class AbstractCalDavBackendTest extends TestCase {
 	protected $principal;
 	/** @var IUserManager|\PHPUnit_Framework_MockObject_MockObject */
 	protected $userManager;
-	/** @var ActivityBackend|\PHPUnit_Framework_MockObject_MockObject */
-	protected $activityBackend;
 
 	/** @var ISecureRandom */
 	private $random;
@@ -63,9 +58,7 @@ abstract class AbstractCalDavBackendTest extends TestCase {
 		parent::setUp();
 
 		$this->userManager = $this->createMock(IUserManager::class);
-		$groupManager = $this->createMock(IGroupManager::class);
-		$activityManager = $this->createMock(IActivityManager::class);
-		$userSession = $this->createMock(IUserSession::class);
+		$dispatcher = $this->createMock(EventDispatcherInterface::class);
 		$this->principal = $this->getMockBuilder('OCA\DAV\Connector\Sabre\Principal')
 			->disableOriginalConstructor()
 			->setMethods(['getPrincipalByPath', 'getGroupMembership'])
@@ -80,10 +73,7 @@ abstract class AbstractCalDavBackendTest extends TestCase {
 
 		$db = \OC::$server->getDatabaseConnection();
 		$this->random = \OC::$server->getSecureRandom();
-		$this->backend = new CalDavBackend($db, $this->principal, $this->userManager, $groupManager, $this->random, $activityManager, $userSession);
-
-		$this->activityBackend = $this->createMock(ActivityBackend::class);
-		$this->invokePrivate($this->backend, 'activityBackend', [$this->activityBackend]);
+		$this->backend = new CalDavBackend($db, $this->principal, $this->userManager, $this->random, $dispatcher);
 
 		$this->cleanUpBackend();
 	}
diff --git a/apps/dav/tests/unit/CalDAV/PublicCalendarRootTest.php b/apps/dav/tests/unit/CalDAV/PublicCalendarRootTest.php
index c3a3d783e18..59fa4747a93 100644
--- a/apps/dav/tests/unit/CalDAV/PublicCalendarRootTest.php
+++ b/apps/dav/tests/unit/CalDAV/PublicCalendarRootTest.php
@@ -2,17 +2,14 @@
 
 namespace OCA\DAV\Tests\unit\CalDAV;
 
-use OCA\DAV\CalDAV\Activity\Backend as ActivityBackend;
 use OCA\DAV\CalDAV\Calendar;
 use OCA\DAV\Connector\Sabre\Principal;
-use OCP\Activity\IManager as IActivityManager;
-use OCP\IGroupManager;
 use OCP\IL10N;
 use OCA\DAV\CalDAV\CalDavBackend;
 use OCA\DAV\CalDAV\PublicCalendarRoot;
 use OCP\IUserManager;
-use OCP\IUserSession;
 use OCP\Security\ISecureRandom;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
 use Test\TestCase;
 
 /**
@@ -35,14 +32,6 @@ class PublicCalendarRootTest extends TestCase {
 	private $principal;
 	/** @var IUserManager|\PHPUnit_Framework_MockObject_MockObject */
 	protected $userManager;
-	/** @var IGroupManager|\PHPUnit_Framework_MockObject_MockObject */
-	protected $groupManager;
-	/** @var IActivityManager|\PHPUnit_Framework_MockObject_MockObject */
-	protected $activityManager;
-	/** @var IUserSession|\PHPUnit_Framework_MockObject_MockObject */
-	protected $userSession;
-	/** @var ActivityBackend|\PHPUnit_Framework_MockObject_MockObject */
-	protected $activityBackend;
 
 	/** @var ISecureRandom */
 	private $random;
@@ -53,24 +42,17 @@ class PublicCalendarRootTest extends TestCase {
 		$db = \OC::$server->getDatabaseConnection();
 		$this->principal = $this->createMock('OCA\DAV\Connector\Sabre\Principal');
 		$this->userManager = $this->createMock(IUserManager::class);
-		$groupManager = $this->createMock(IGroupManager::class);
-		$activityManager = $this->createMock(IActivityManager::class);
-		$userSession = $this->createMock(IUserSession::class);
 		$this->random = \OC::$server->getSecureRandom();
+		$dispatcher = $this->createMock(EventDispatcherInterface::class);
 
 		$this->backend = new CalDavBackend(
 			$db,
 			$this->principal,
 			$this->userManager,
-			$groupManager,
 			$this->random,
-			$activityManager,
-			$userSession
+			$dispatcher
 		);
 
-		$this->activityBackend = $this->createMock(ActivityBackend::class);
-		$this->invokePrivate($this->backend, 'activityBackend', [$this->activityBackend]);
-
 		$this->publicCalendarRoot = new PublicCalendarRoot($this->backend);
 
 		$this->l10n = $this->getMockBuilder('\OCP\IL10N')
@@ -95,14 +77,6 @@ class PublicCalendarRootTest extends TestCase {
 	}
 
 	public function testGetChild() {
-		$this->activityBackend->expects($this->exactly(1))
-			->method('addCalendar');
-		$this->activityBackend->expects($this->never())
-			->method('updateCalendar');
-		$this->activityBackend->expects($this->never())
-			->method('deleteCalendar');
-		$this->activityBackend->expects($this->never())
-			->method('updateCalendarShares');
 
 		$calendar = $this->createPublicCalendar();
 
@@ -117,15 +91,6 @@ class PublicCalendarRootTest extends TestCase {
 	}
 
 	public function testGetChildren() {
-		$this->activityBackend->expects($this->exactly(1))
-			->method('addCalendar');
-		$this->activityBackend->expects($this->never())
-			->method('updateCalendar');
-		$this->activityBackend->expects($this->never())
-			->method('deleteCalendar');
-		$this->activityBackend->expects($this->never())
-			->method('updateCalendarShares');
-
 		$this->createPublicCalendar();
 
 		$publicCalendars = $this->backend->getPublicCalendars();