Dont use isSyncMaintained

lib/private/Group/Backend.php

@@ -133,8 +133,4 @@ public function usersInGroup($gid, $search = '', $limit = -1, $offset = 0) {
 	public function isVisibleForScope($scope) {
 		return true;
 	}
-
-	public function isSyncMaintained() {
-		return false;
-	}
 }

lib/private/Group/Database.php

@@ -149,11 +149,4 @@ public function groupExists($groupName) {
 		$stmt->closeCursor();
 		return isset($data['exists']);
 	}
-
-	/**
-	 * Groups and memberships of this backend are maintained by the users
-	 */
-	public function isSyncMaintained() {
-		return false;
-	}
 }

lib/private/Group/SyncService.php

@@ -51,6 +51,10 @@ class SyncService {
 	private $logger;
 	/** @var string[] backendclass -> gid array map */
 	private $prefetchedGroupIds;
+	/** @var string[] backendclass -> BackendGroup array map */
+	private $membershipsByBackend;
+	/** @var string uid - uid of last user for which sync was run */
+	private $lastUser;
 
 	/**
 	 * SyncService constructor.
@@ -69,6 +73,8 @@ public function __construct(GroupMapper $groupMapper,
 		$this->membershipManager = $membershipManager;
 		$this->logger = $logger;
 		$this->prefetchedGroupIds = [];
+		$this->membershipsByBackend = [];
+		$this->lastUser = null;
 	}
 
 	/**
@@ -221,13 +227,7 @@ public function syncUserMemberships(GroupInterface $backend, $uid) {
 			$remoteGids = $backend->getUserGroups($uid);
 
 			/* @var BackendGroup[] $localSyncGidGroupMap */
-			$localSyncGidGroupMap = [];
-			$localSyncGroups = $this->membershipManager->getMemberBackendGroupsByType($uid,
-				MembershipManager::MEMBERSHIP_TYPE_GROUP_USER,
-				MembershipManager::MAINTENANCE_TYPE_SYNC);
-			foreach($localSyncGroups as $localSyncGroup) {
-				$localSyncGidGroupMap[$localSyncGroup->getGroupId()] = $localSyncGroup;
-			}
+			$localSyncGidGroupMap = $this->getLocalBackendMemberships($backend, $uid);
 
 			// Check which memberships need to removed or added
 			$membershipsToRemove = array_diff(array_keys($localSyncGidGroupMap), $remoteGids);
@@ -278,6 +278,39 @@ public function syncUserMemberships(GroupInterface $backend, $uid) {
 		);
 	}
 
+	/**
+	 * Return gid->BackendGroup map of user groups for this backend
+	 *
+	 * @param GroupInterface $backend
+	 * @param $uid
+	 */
+	private function getLocalBackendMemberships(GroupInterface $backend, $uid) {
+		if ($this->lastUser !== $uid) {
+			// Fetch all memberships for this user and segregate by backend class
+			$this->lastUser = $uid;
+			$this->membershipsByBackend = [];
+
+			/* @var BackendGroup[] $localSyncGroups */
+			$localSyncGroups = $this->membershipManager->getMemberBackendGroupsByType($uid,
+				MembershipManager::MEMBERSHIP_TYPE_GROUP_USER,
+				MembershipManager::MAINTENANCE_TYPE_SYNC);
+			foreach($localSyncGroups as $localSyncGroup) {
+				if (!isset($this->membershipsByBackend[$localSyncGroup->getBackend()])) {
+					$this->membershipsByBackend[$localSyncGroup->getBackend()] = [];
+				}
+				$this->membershipsByBackend[$localSyncGroup->getBackend()][$localSyncGroup->getGroupId()] = $localSyncGroup;
+			}
+		}
+
+		// Return and invalidate the cache for selected backend
+		if (isset($this->membershipsByBackend[get_class($backend)])) {
+			$memberships = $this->membershipsByBackend[get_class($backend)];
+			unset($this->membershipsByBackend[get_class($backend)]);
+			return $memberships;
+		}
+		return [];
+	}
+
 	/**
 	 * Fetch backend service groups and
 	 * use callback function for each of the groups, if callback has been specified.

lib/private/User/Session.php

@@ -495,9 +495,7 @@ public function tryBasicAuthLogin(IRequest $request) {
 	private function updateUserMemberships(IUser $user) {
 		// Update only the backends which are sync maintained
 		foreach($this->groupManager->getBackends() as $groupBackend) {
-			if ($groupBackend->isSyncMaintained()) {
-				$this->groupSyncService->syncUserMemberships($groupBackend, $user->getUID());
-			}
+			$this->groupSyncService->syncUserMemberships($groupBackend, $user->getUID());
 		};
 	}
 

lib/public/GroupInterface.php

@@ -126,12 +126,4 @@ public function usersInGroup($gid, $search = '', $limit = -1, $offset = 0);
 	 */
 	public function isVisibleForScope($scope);
 
-	/**
-	 * Returns whether the groups and memberships are to be maintained by core
-	 * and sync mechanism to be used.
-	 *
-	 * @since 10.0.0
-	 */
-	public function isSyncMaintained();
-
 }

tests/Core/Command/Group/SyncBackendTest.php

@@ -101,7 +101,6 @@ protected function setUp() {
 				'addToGroup',
 				'removeFromGroup',
 				'isVisibleForScope',
-				'isSyncMaintained',
 			])
 			->getMock();
 		$this->userBackend1 = $this->getMockBuilder(UserInterface::class)

tests/lib/Group/ManagerTest.php

@@ -90,8 +90,7 @@ private function getTestBackend($implementedActions = null, $visibleForScopes =
 				'deleteGroup',
 				'addToGroup',
 				'removeFromGroup',
-				'isVisibleForScope',
-				'isSyncMaintained'
+				'isVisibleForScope'
 			])
 			->getMock();
 		$backend->expects($this->any())

tests/lib/Group/SyncServiceTest.php

@@ -80,7 +80,6 @@ public function setUp() {
 				'addToGroup',
 				'removeFromGroup',
 				'isVisibleForScope',
-				'isSyncMaintained',
 			])
 			->getMock();
 

tests/lib/User/SessionTest.php

@@ -76,9 +76,6 @@ protected function setUp() {
 		$this->groupSyncService = $this->createMock(\OC\Group\SyncService::class);
 
 		$groupBackend = $this->createMock(GroupInterface::class);
-		$groupBackend->expects($this->any())
-			->method('isSyncMaintained')
-			->willReturn(true);
 		$this->groupManager->expects($this->any())
 			->method('getBackends')
 			->willReturn([$groupBackend]);
@@ -1052,17 +1049,17 @@ public function testLogout() {
 			->method('set')
 			->with('user_id', 'foo');
 
-		/** @var Manager $manager */
-		$manager = $this->createMock(Manager::class);
+		/** @var Manager $userManager */
+		$userManager = $this->createMock(Manager::class);
 
 		/** @var IUser | \PHPUnit_Framework_MockObject_MockObject $user */
 		$user = $this->createMock(IUser::class);
 		$user->expects($this->once())
 			->method('getUID')
 			->will($this->returnValue('foo'));
 
-		$userSession = new Session($manager, $session, $this->timeFactory,
-			$this->tokenProvider, $this->config, $this->serviceLoader, $this->userSyncService);
+		$userSession = new Session($userManager, $this->groupManager, $session, $this->timeFactory,
+			$this->tokenProvider, $this->config, $this->serviceLoader, $this->userSyncService, $this->groupSyncService);
 		$userSession->setUser($user);
 
 		$this->assertTrue($userSession->logout());