nextcloud / server

apps/provisioning_api/lib/Controller/GroupsController.php

Indentation +213 added lines, -213 removed lines

@@ -44,239 +44,239 @@
 
 class GroupsController extends AUserData {
 
-	/** @var ILogger */
-	private $logger;
+    /** @var ILogger */
+    private $logger;
 
-	/**
-	 * @param string $appName
-	 * @param IRequest $request
-	 * @param IUserManager $userManager
-	 * @param IConfig $config
-	 * @param IGroupManager $groupManager
-	 * @param IUserSession $userSession
-	 * @param AccountManager $accountManager
-	 * @param ILogger $logger
-	 * @param UsersController $userController
-	 */
-	public function __construct(string $appName,
-								IRequest $request,
-								IUserManager $userManager,
-								IConfig $config,
-								IGroupManager $groupManager,
-								IUserSession $userSession,
-								AccountManager $accountManager,
-								ILogger $logger) {
-		parent::__construct($appName,
-			$request,
-			$userManager,
-			$config,
-			$groupManager,
-			$userSession,
-			$accountManager);
+    /**
+     * @param string $appName
+     * @param IRequest $request
+     * @param IUserManager $userManager
+     * @param IConfig $config
+     * @param IGroupManager $groupManager
+     * @param IUserSession $userSession
+     * @param AccountManager $accountManager
+     * @param ILogger $logger
+     * @param UsersController $userController
+     */
+    public function __construct(string $appName,
+                                IRequest $request,
+                                IUserManager $userManager,
+                                IConfig $config,
+                                IGroupManager $groupManager,
+                                IUserSession $userSession,
+                                AccountManager $accountManager,
+                                ILogger $logger) {
+        parent::__construct($appName,
+            $request,
+            $userManager,
+            $config,
+            $groupManager,
+            $userSession,
+            $accountManager);
 
-		$this->logger = $logger;
-	}
+        $this->logger = $logger;
+    }
 
-	/**
-	 * returns a list of groups
-	 *
-	 * @NoAdminRequired
-	 *
-	 * @param string $search
-	 * @param int $limit
-	 * @param int $offset
-	 * @return DataResponse
-	 */
-	public function getGroups(string $search = '', int $limit = null, int $offset = 0): DataResponse {
-		$groups = $this->groupManager->search($search, $limit, $offset);
-		$groups = array_map(function($group) {
-			/** @var IGroup $group */
-			return $group->getGID();
-		}, $groups);
+    /**
+     * returns a list of groups
+     *
+     * @NoAdminRequired
+     *
+     * @param string $search
+     * @param int $limit
+     * @param int $offset
+     * @return DataResponse
+     */
+    public function getGroups(string $search = '', int $limit = null, int $offset = 0): DataResponse {
+        $groups = $this->groupManager->search($search, $limit, $offset);
+        $groups = array_map(function($group) {
+            /** @var IGroup $group */
+            return $group->getGID();
+        }, $groups);
 
-		return new DataResponse(['groups' => $groups]);
-	}
+        return new DataResponse(['groups' => $groups]);
+    }
 
-	/**
-	 * returns a list of groups details with ids and displaynames
-	 *
-	 * @NoAdminRequired
-	 *
-	 * @param string $search
-	 * @param int $limit
-	 * @param int $offset
-	 * @return DataResponse
-	 */
-	public function getGroupsDetails(string $search = '', int $limit = null, int $offset = 0): DataResponse {
-		$groups = $this->groupManager->search($search, $limit, $offset);
-		$groups = array_map(function($group) {
-			/** @var IGroup $group */
-			return ['id' => $group->getGID(), 'displayname' => $group->getDisplayName()];
-		}, $groups);
+    /**
+     * returns a list of groups details with ids and displaynames
+     *
+     * @NoAdminRequired
+     *
+     * @param string $search
+     * @param int $limit
+     * @param int $offset
+     * @return DataResponse
+     */
+    public function getGroupsDetails(string $search = '', int $limit = null, int $offset = 0): DataResponse {
+        $groups = $this->groupManager->search($search, $limit, $offset);
+        $groups = array_map(function($group) {
+            /** @var IGroup $group */
+            return ['id' => $group->getGID(), 'displayname' => $group->getDisplayName()];
+        }, $groups);
 
-		return new DataResponse(['groups' => $groups]);
-	}
+        return new DataResponse(['groups' => $groups]);
+    }
 
-	/**
-	 * @NoAdminRequired
-	 *
-	 * @param string $groupId
-	 * @return DataResponse
-	 * @throws OCSException	
-	 *
-	 * @deprecated 14 Use getGroupUsers
-	 */
-	public function getGroup(string $groupId): DataResponse {
-		return $this->getGroupUsers($groupId);
-	}
+    /**
+     * @NoAdminRequired
+     *
+     * @param string $groupId
+     * @return DataResponse
+     * @throws OCSException	
+     *
+     * @deprecated 14 Use getGroupUsers
+     */
+    public function getGroup(string $groupId): DataResponse {
+        return $this->getGroupUsers($groupId);
+    }
 
-	/**
-	 * returns an array of users in the specified group
-	 *
-	 * @NoAdminRequired
-	 *
-	 * @param string $groupId
-	 * @return DataResponse
-	 * @throws OCSException
-	 */
-	public function getGroupUsers(string $groupId): DataResponse {
-		$user = $this->userSession->getUser();
-		$isSubadminOfGroup = false;
+    /**
+     * returns an array of users in the specified group
+     *
+     * @NoAdminRequired
+     *
+     * @param string $groupId
+     * @return DataResponse
+     * @throws OCSException
+     */
+    public function getGroupUsers(string $groupId): DataResponse {
+        $user = $this->userSession->getUser();
+        $isSubadminOfGroup = false;
 
-		// Check the group exists
-		$group = $this->groupManager->get($groupId);
-		if ($group !== null) {
-			$isSubadminOfGroup =$this->groupManager->getSubAdmin()->isSubAdminOfGroup($user, $group);
-		} else {
-			throw new OCSNotFoundException('The requested group could not be found');
-		}
+        // Check the group exists
+        $group = $this->groupManager->get($groupId);
+        if ($group !== null) {
+            $isSubadminOfGroup =$this->groupManager->getSubAdmin()->isSubAdminOfGroup($user, $group);
+        } else {
+            throw new OCSNotFoundException('The requested group could not be found');
+        }
 
-		// Check subadmin has access to this group
-		if($this->groupManager->isAdmin($user->getUID())
-		   || $isSubadminOfGroup) {
-			$users = $this->groupManager->get($groupId)->getUsers();
-			$users =  array_map(function($user) {
-				/** @var IUser $user */
-				return $user->getUID();
-			}, $users);
-			$users = array_values($users);
-			return new DataResponse(['users' => $users]);
-		}
+        // Check subadmin has access to this group
+        if($this->groupManager->isAdmin($user->getUID())
+           || $isSubadminOfGroup) {
+            $users = $this->groupManager->get($groupId)->getUsers();
+            $users =  array_map(function($user) {
+                /** @var IUser $user */
+                return $user->getUID();
+            }, $users);
+            $users = array_values($users);
+            return new DataResponse(['users' => $users]);
+        }
 
-		throw new OCSForbiddenException();
-	}
+        throw new OCSForbiddenException();
+    }
 
-	/**
-	 * returns an array of users details in the specified group
-	 *
-	 * @NoAdminRequired
-	 *
-	 * @param string $groupId
-	 * @param int $limit
-	 * @param int $offset
-	 * @return DataResponse
-	 * @throws OCSException
-	 */
-	public function getGroupUsersDetails(string $groupId, int $limit = null, int $offset = 0): DataResponse {
-		$user = $this->userSession->getUser();
-		$isSubadminOfGroup = false;
+    /**
+     * returns an array of users details in the specified group
+     *
+     * @NoAdminRequired
+     *
+     * @param string $groupId
+     * @param int $limit
+     * @param int $offset
+     * @return DataResponse
+     * @throws OCSException
+     */
+    public function getGroupUsersDetails(string $groupId, int $limit = null, int $offset = 0): DataResponse {
+        $user = $this->userSession->getUser();
+        $isSubadminOfGroup = false;
 
-		// Check the group exists
-		$group = $this->groupManager->get($groupId);
-		if ($group !== null) {
-			$isSubadminOfGroup =$this->groupManager->getSubAdmin()->isSubAdminOfGroup($user, $group);
-		} else {
-			throw new OCSException('The requested group could not be found', \OCP\API::RESPOND_NOT_FOUND);
-		}
+        // Check the group exists
+        $group = $this->groupManager->get($groupId);
+        if ($group !== null) {
+            $isSubadminOfGroup =$this->groupManager->getSubAdmin()->isSubAdminOfGroup($user, $group);
+        } else {
+            throw new OCSException('The requested group could not be found', \OCP\API::RESPOND_NOT_FOUND);
+        }
 
-		// Check subadmin has access to this group
-		if($this->groupManager->isAdmin($user->getUID())
-		   || $isSubadminOfGroup) {
-			$users = $this->groupManager->get($groupId)->getUsers();
-			// Extract required number
-			$users = array_slice($users, $offset, $limit);
-			$users = array_keys($users);
-			$usersDetails = [];
-			foreach ($users as $userId) {
-				$userData = $this->getUserData($userId);
-				// Do not insert empty entry
-				if(!empty($userData)) {
-					$usersDetails[$userId] = $userData;
-				}
-			}
-			return new DataResponse(['users' => $usersDetails]);
-		}
+        // Check subadmin has access to this group
+        if($this->groupManager->isAdmin($user->getUID())
+           || $isSubadminOfGroup) {
+            $users = $this->groupManager->get($groupId)->getUsers();
+            // Extract required number
+            $users = array_slice($users, $offset, $limit);
+            $users = array_keys($users);
+            $usersDetails = [];
+            foreach ($users as $userId) {
+                $userData = $this->getUserData($userId);
+                // Do not insert empty entry
+                if(!empty($userData)) {
+                    $usersDetails[$userId] = $userData;
+                }
+            }
+            return new DataResponse(['users' => $usersDetails]);
+        }
 
-		throw new OCSException('User does not have access to specified group', \OCP\API::RESPOND_UNAUTHORISED);
-	}
+        throw new OCSException('User does not have access to specified group', \OCP\API::RESPOND_UNAUTHORISED);
+    }
 
-	/**
-	 * creates a new group
-	 *
-	 * @PasswordConfirmationRequired
-	 *
-	 * @param string $groupid
-	 * @return DataResponse
-	 * @throws OCSException
-	 */
-	public function addGroup(string $groupid): DataResponse {
-		// Validate name
-		if(empty($groupid)) {
-			$this->logger->error('Group name not supplied', ['app' => 'provisioning_api']);
-			throw new OCSException('Invalid group name', 101);
-		}
-		// Check if trying to create an admin group
-		if (trim(strtolower($groupid)) === 'admin') {
-			throw new OCSException('', 102);
-		}
-		// Check if it exists
-		if($this->groupManager->groupExists($groupid)){
-			throw new OCSException('', 102);
-		}
-		$this->groupManager->createGroup($groupid);
-		return new DataResponse();
-	}
+    /**
+     * creates a new group
+     *
+     * @PasswordConfirmationRequired
+     *
+     * @param string $groupid
+     * @return DataResponse
+     * @throws OCSException
+     */
+    public function addGroup(string $groupid): DataResponse {
+        // Validate name
+        if(empty($groupid)) {
+            $this->logger->error('Group name not supplied', ['app' => 'provisioning_api']);
+            throw new OCSException('Invalid group name', 101);
+        }
+        // Check if trying to create an admin group
+        if (trim(strtolower($groupid)) === 'admin') {
+            throw new OCSException('', 102);
+        }
+        // Check if it exists
+        if($this->groupManager->groupExists($groupid)){
+            throw new OCSException('', 102);
+        }
+        $this->groupManager->createGroup($groupid);
+        return new DataResponse();
+    }
 
-	/**
-	 * @PasswordConfirmationRequired
-	 *
-	 * @param string $groupId
-	 * @return DataResponse
-	 * @throws OCSException
-	 */
-	public function deleteGroup(string $groupId): DataResponse {
-		// Check it exists
-		if(!$this->groupManager->groupExists($groupId)){
-			throw new OCSException('', 101);
-		} else if($groupId === 'admin' || !$this->groupManager->get($groupId)->delete()){
-			// Cannot delete admin group
-			throw new OCSException('', 102);
-		}
+    /**
+     * @PasswordConfirmationRequired
+     *
+     * @param string $groupId
+     * @return DataResponse
+     * @throws OCSException
+     */
+    public function deleteGroup(string $groupId): DataResponse {
+        // Check it exists
+        if(!$this->groupManager->groupExists($groupId)){
+            throw new OCSException('', 101);
+        } else if($groupId === 'admin' || !$this->groupManager->get($groupId)->delete()){
+            // Cannot delete admin group
+            throw new OCSException('', 102);
+        }
 
-		return new DataResponse();
-	}
+        return new DataResponse();
+    }
 
-	/**
-	 * @param string $groupId
-	 * @return DataResponse
-	 * @throws OCSException
-	 */
-	public function getSubAdminsOfGroup(string $groupId): DataResponse {
-		// Check group exists
-		$targetGroup = $this->groupManager->get($groupId);
-		if($targetGroup === null) {
-			throw new OCSException('Group does not exist', 101);
-		}
+    /**
+     * @param string $groupId
+     * @return DataResponse
+     * @throws OCSException
+     */
+    public function getSubAdminsOfGroup(string $groupId): DataResponse {
+        // Check group exists
+        $targetGroup = $this->groupManager->get($groupId);
+        if($targetGroup === null) {
+            throw new OCSException('Group does not exist', 101);
+        }
 
-		/** @var IUser[] $subadmins */
-		$subadmins = $this->groupManager->getSubAdmin()->getGroupsSubAdmins($targetGroup);
-		// New class returns IUser[] so convert back
-		$uids = [];
-		foreach ($subadmins as $user) {
-			$uids[] = $user->getUID();
-		}
+        /** @var IUser[] $subadmins */
+        $subadmins = $this->groupManager->getSubAdmin()->getGroupsSubAdmins($targetGroup);
+        // New class returns IUser[] so convert back
+        $uids = [];
+        foreach ($subadmins as $user) {
+            $uids[] = $user->getUID();
+        }
 
-		return new DataResponse($uids);
-	}
+        return new DataResponse($uids);
+    }
 
 }

Spacing +11 added lines, -11 removed lines

@@ -146,16 +146,16 @@ 
 		// Check the group exists
 		$group = $this->groupManager->get($groupId);
 		if ($group !== null) {
-			$isSubadminOfGroup =$this->groupManager->getSubAdmin()->isSubAdminOfGroup($user, $group);
+			$isSubadminOfGroup = $this->groupManager->getSubAdmin()->isSubAdminOfGroup($user, $group);
 		} else {
 			throw new OCSNotFoundException('The requested group could not be found');
 		}
 
 		// Check subadmin has access to this group
-		if($this->groupManager->isAdmin($user->getUID())
+		if ($this->groupManager->isAdmin($user->getUID())
 		   || $isSubadminOfGroup) {
 			$users = $this->groupManager->get($groupId)->getUsers();
-			$users =  array_map(function($user) {
+			$users = array_map(function($user) {
 				/** @var IUser $user */
 				return $user->getUID();
 			}, $users);
@@ -184,13 +184,13 @@ 
 		// Check the group exists
 		$group = $this->groupManager->get($groupId);
 		if ($group !== null) {
-			$isSubadminOfGroup =$this->groupManager->getSubAdmin()->isSubAdminOfGroup($user, $group);
+			$isSubadminOfGroup = $this->groupManager->getSubAdmin()->isSubAdminOfGroup($user, $group);
 		} else {
 			throw new OCSException('The requested group could not be found', \OCP\API::RESPOND_NOT_FOUND);
 		}
 
 		// Check subadmin has access to this group
-		if($this->groupManager->isAdmin($user->getUID())
+		if ($this->groupManager->isAdmin($user->getUID())
 		   || $isSubadminOfGroup) {
 			$users = $this->groupManager->get($groupId)->getUsers();
 			// Extract required number
@@ -200,7 +200,7 @@ 
 			foreach ($users as $userId) {
 				$userData = $this->getUserData($userId);
 				// Do not insert empty entry
-				if(!empty($userData)) {
+				if (!empty($userData)) {
 					$usersDetails[$userId] = $userData;
 				}
 			}
@@ -221,7 +221,7 @@ 
 	 */
 	public function addGroup(string $groupid): DataResponse {
 		// Validate name
-		if(empty($groupid)) {
+		if (empty($groupid)) {
 			$this->logger->error('Group name not supplied', ['app' => 'provisioning_api']);
 			throw new OCSException('Invalid group name', 101);
 		}
@@ -230,7 +230,7 @@ 
 			throw new OCSException('', 102);
 		}
 		// Check if it exists
-		if($this->groupManager->groupExists($groupid)){
+		if ($this->groupManager->groupExists($groupid)) {
 			throw new OCSException('', 102);
 		}
 		$this->groupManager->createGroup($groupid);
@@ -246,9 +246,9 @@ 
 	 */
 	public function deleteGroup(string $groupId): DataResponse {
 		// Check it exists
-		if(!$this->groupManager->groupExists($groupId)){
+		if (!$this->groupManager->groupExists($groupId)) {
 			throw new OCSException('', 101);
-		} else if($groupId === 'admin' || !$this->groupManager->get($groupId)->delete()){
+		} else if ($groupId === 'admin' || !$this->groupManager->get($groupId)->delete()) {
 			// Cannot delete admin group
 			throw new OCSException('', 102);
 		}
@@ -264,7 +264,7 @@ 
 	public function getSubAdminsOfGroup(string $groupId): DataResponse {
 		// Check group exists
 		$targetGroup = $this->groupManager->get($groupId);
-		if($targetGroup === null) {
+		if ($targetGroup === null) {
 			throw new OCSException('Group does not exist', 101);
 		}
 

lib/private/Group/Manager.php

Indentation +346 added lines, -346 removed lines

@@ -61,350 +61,350 @@
  * @package OC\Group
  */
 class Manager extends PublicEmitter implements IGroupManager {
-	/**
-	 * @var GroupInterface[] $backends
-	 */
-	private $backends = array();
-
-	/**
-	 * @var \OC\User\Manager $userManager
-	 */
-	private $userManager;
-
-	/**
-	 * @var \OC\Group\Group[]
-	 */
-	private $cachedGroups = array();
-
-	/**
-	 * @var \OC\Group\Group[]
-	 */
-	private $cachedUserGroups = array();
-
-	/** @var \OC\SubAdmin */
-	private $subAdmin = null;
-
-	/** @var ILogger */
-	private $logger;
-
-	/**
-	 * @param \OC\User\Manager $userManager
-	 * @param ILogger $logger
-	 */
-	public function __construct(\OC\User\Manager $userManager, ILogger $logger) {
-		$this->userManager = $userManager;
-		$this->logger = $logger;
-		$cachedGroups = & $this->cachedGroups;
-		$cachedUserGroups = & $this->cachedUserGroups;
-		$this->listen('\OC\Group', 'postDelete', function ($group) use (&$cachedGroups, &$cachedUserGroups) {
-			/**
-			 * @var \OC\Group\Group $group
-			 */
-			unset($cachedGroups[$group->getGID()]);
-			$cachedUserGroups = array();
-		});
-		$this->listen('\OC\Group', 'postAddUser', function ($group) use (&$cachedUserGroups) {
-			/**
-			 * @var \OC\Group\Group $group
-			 */
-			$cachedUserGroups = array();
-		});
-		$this->listen('\OC\Group', 'postRemoveUser', function ($group) use (&$cachedUserGroups) {
-			/**
-			 * @var \OC\Group\Group $group
-			 */
-			$cachedUserGroups = array();
-		});
-	}
-
-	/**
-	 * Checks whether a given backend is used
-	 *
-	 * @param string $backendClass Full classname including complete namespace
-	 * @return bool
-	 */
-	public function isBackendUsed($backendClass) {
-		$backendClass = strtolower(ltrim($backendClass, '\\'));
-
-		foreach ($this->backends as $backend) {
-			if (strtolower(get_class($backend)) === $backendClass) {
-				return true;
-			}
-		}
-
-		return false;
-	}
-
-	/**
-	 * @param \OCP\GroupInterface $backend
-	 */
-	public function addBackend($backend) {
-		$this->backends[] = $backend;
-		$this->clearCaches();
-	}
-
-	public function clearBackends() {
-		$this->backends = array();
-		$this->clearCaches();
-	}
-
-	/**
-	 * Get the active backends
-	 * @return \OCP\GroupInterface[]
-	 */
-	public function getBackends() {
-		return $this->backends;
-	}
-
-
-	protected function clearCaches() {
-		$this->cachedGroups = array();
-		$this->cachedUserGroups = array();
-	}
-
-	/**
-	 * @param string $gid
-	 * @return \OC\Group\Group
-	 */
-	public function get($gid) {
-		if (isset($this->cachedGroups[$gid])) {
-			return $this->cachedGroups[$gid];
-		}
-		return $this->getGroupObject($gid);
-	}
-
-	/**
-	 * @param string $gid
-	 * @param string $displayName
-	 * @return \OCP\IGroup
-	 */
-	protected function getGroupObject($gid, $displayName = null) {
-		$backends = array();
-		foreach ($this->backends as $backend) {
-			if ($backend->implementsActions(\OC\Group\Backend::GROUP_DETAILS)) {
-				$groupData = $backend->getGroupDetails($gid);
-				if (is_array($groupData)) {
-					// take the display name from the first backend that has a non-null one
-					if (is_null($displayName) && isset($groupData['displayName'])) {
-						$displayName = $groupData['displayName'];
-					}
-					$backends[] = $backend;
-				}
-			} else if ($backend->groupExists($gid)) {
-				$backends[] = $backend;
-			}
-		}
-		if (count($backends) === 0) {
-			return null;
-		}
-		$this->cachedGroups[$gid] = new Group($gid, $backends, $this->userManager, $this, $displayName);
-		return $this->cachedGroups[$gid];
-	}
-
-	/**
-	 * @param string $gid
-	 * @return bool
-	 */
-	public function groupExists($gid) {
-		return $this->get($gid) instanceof IGroup;
-	}
-
-	/**
-	 * @param string $gid
-	 * @return \OC\Group\Group
-	 */
-	public function createGroup($gid) {
-		if ($gid === '' || $gid === null) {
-			return false;
-		} else if (trim(strtolower($gid)) === 'admin' && $this->get('admin')) {
-			return $this->get('admin');
-		} else if ($group = $this->get($gid)) {
-			return $group;
-		} else {
-			$this->emit('\OC\Group', 'preCreate', array($gid));
-			foreach ($this->backends as $backend) {
-				if ($backend->implementsActions(\OC\Group\Backend::CREATE_GROUP)) {
-					$backend->createGroup($gid);
-					$group = $this->getGroupObject($gid);
-					$this->emit('\OC\Group', 'postCreate', array($group));
-					return $group;
-				}
-			}
-			return null;
-		}
-	}
-
-	/**
-	 * @param string $search
-	 * @param int $limit
-	 * @param int $offset
-	 * @return \OC\Group\Group[]
-	 */
-	public function search($search, $limit = null, $offset = null) {
-		$groups = array();
-		foreach ($this->backends as $backend) {
-			$groupIds = $backend->getGroups($search, $limit, $offset);
-			foreach ($groupIds as $groupId) {
-				$aGroup = $this->get($groupId);
-				if ($aGroup instanceof IGroup) {
-					$groups[$groupId] = $aGroup;
-				} else {
-					$this->logger->debug('Group "' . $groupId . '" was returned by search but not found through direct access', ['app' => 'core']);
-				}
-			}
-			if (!is_null($limit) and $limit <= 0) {
-				return array_values($groups);
-			}
-		}
-		return array_values($groups);
-	}
-
-	/**
-	 * @param IUser|null $user
-	 * @return \OC\Group\Group[]
-	 */
-	public function getUserGroups(IUser $user= null) {
-		if (!$user instanceof IUser) {
-			return [];
-		}
-		return $this->getUserIdGroups($user->getUID());
-	}
-
-	/**
-	 * @param string $uid the user id
-	 * @return \OC\Group\Group[]
-	 */
-	public function getUserIdGroups($uid) {
-		if (isset($this->cachedUserGroups[$uid])) {
-			return $this->cachedUserGroups[$uid];
-		}
-		$groups = array();
-		foreach ($this->backends as $backend) {
-			$groupIds = $backend->getUserGroups($uid);
-			if (is_array($groupIds)) {
-				foreach ($groupIds as $groupId) {
-					$aGroup = $this->get($groupId);
-					if ($aGroup instanceof IGroup) {
-						$groups[$groupId] = $aGroup;
-					} else {
-						$this->logger->debug('User "' . $uid . '" belongs to deleted group: "' . $groupId . '"', ['app' => 'core']);
-					}
-				}
-			}
-		}
-		$this->cachedUserGroups[$uid] = $groups;
-		return $this->cachedUserGroups[$uid];
-	}
-
-	/**
-	 * Checks if a userId is in the admin group
-	 * @param string $userId
-	 * @return bool if admin
-	 */
-	public function isAdmin($userId) {
-		foreach ($this->backends as $backend) {
-			if ($backend->implementsActions(\OC\Group\Backend::IS_ADMIN) && $backend->isAdmin($userId)) {
-				return true;
-			}
-		}
-		return $this->isInGroup($userId, 'admin');
-	}
-
-	/**
-	 * Checks if a userId is in a group
-	 * @param string $userId
-	 * @param string $group
-	 * @return bool if in group
-	 */
-	public function isInGroup($userId, $group) {
-		return array_key_exists($group, $this->getUserIdGroups($userId));
-	}
-
-	/**
-	 * get a list of group ids for a user
-	 * @param IUser $user
-	 * @return array with group ids
-	 */
-	public function getUserGroupIds(IUser $user) {
-		return array_map(function($value) {
-			return (string) $value;
-		}, array_keys($this->getUserGroups($user)));
-	}
-
-	/**
-	 * get an array of groupid and displayName for a user
-	 * @param IUser $user
-	 * @return array ['displayName' => displayname]
-	 */
-	public function getUserGroupNames(IUser $user) {
-		return array_map(function($group) {
-			return array('displayName' => $group->getDisplayName());
-		}, $this->getUserGroups($user));
-	}
-
-	/**
-	 * get a list of all display names in a group
-	 * @param string $gid
-	 * @param string $search
-	 * @param int $limit
-	 * @param int $offset
-	 * @return array an array of display names (value) and user ids (key)
-	 */
-	public function displayNamesInGroup($gid, $search = '', $limit = -1, $offset = 0) {
-		$group = $this->get($gid);
-		if(is_null($group)) {
-			return array();
-		}
-
-		$search = trim($search);
-		$groupUsers = array();
-
-		if(!empty($search)) {
-			// only user backends have the capability to do a complex search for users
-			$searchOffset = 0;
-			$searchLimit = $limit * 100;
-			if($limit === -1) {
-				$searchLimit = 500;
-			}
-
-			do {
-				$filteredUsers = $this->userManager->searchDisplayName($search, $searchLimit, $searchOffset);
-				foreach($filteredUsers as $filteredUser) {
-					if($group->inGroup($filteredUser)) {
-						$groupUsers[]= $filteredUser;
-					}
-				}
-				$searchOffset += $searchLimit;
-			} while(count($groupUsers) < $searchLimit+$offset && count($filteredUsers) >= $searchLimit);
-
-			if($limit === -1) {
-				$groupUsers = array_slice($groupUsers, $offset);
-			} else {
-				$groupUsers = array_slice($groupUsers, $offset, $limit);
-			}
-		} else {
-			$groupUsers = $group->searchUsers('', $limit, $offset);
-		}
-
-		$matchingUsers = array();
-		foreach($groupUsers as $groupUser) {
-			$matchingUsers[$groupUser->getUID()] = $groupUser->getDisplayName();
-		}
-		return $matchingUsers;
-	}
-
-	/**
-	 * @return \OC\SubAdmin
-	 */
-	public function getSubAdmin() {
-		if (!$this->subAdmin) {
-			$this->subAdmin = new \OC\SubAdmin(
-				$this->userManager,
-				$this,
-				\OC::$server->getDatabaseConnection()
-			);
-		}
-
-		return $this->subAdmin;
-	}
+    /**
+     * @var GroupInterface[] $backends
+     */
+    private $backends = array();
+
+    /**
+     * @var \OC\User\Manager $userManager
+     */
+    private $userManager;
+
+    /**
+     * @var \OC\Group\Group[]
+     */
+    private $cachedGroups = array();
+
+    /**
+     * @var \OC\Group\Group[]
+     */
+    private $cachedUserGroups = array();
+
+    /** @var \OC\SubAdmin */
+    private $subAdmin = null;
+
+    /** @var ILogger */
+    private $logger;
+
+    /**
+     * @param \OC\User\Manager $userManager
+     * @param ILogger $logger
+     */
+    public function __construct(\OC\User\Manager $userManager, ILogger $logger) {
+        $this->userManager = $userManager;
+        $this->logger = $logger;
+        $cachedGroups = & $this->cachedGroups;
+        $cachedUserGroups = & $this->cachedUserGroups;
+        $this->listen('\OC\Group', 'postDelete', function ($group) use (&$cachedGroups, &$cachedUserGroups) {
+            /**
+             * @var \OC\Group\Group $group
+             */
+            unset($cachedGroups[$group->getGID()]);
+            $cachedUserGroups = array();
+        });
+        $this->listen('\OC\Group', 'postAddUser', function ($group) use (&$cachedUserGroups) {
+            /**
+             * @var \OC\Group\Group $group
+             */
+            $cachedUserGroups = array();
+        });
+        $this->listen('\OC\Group', 'postRemoveUser', function ($group) use (&$cachedUserGroups) {
+            /**
+             * @var \OC\Group\Group $group
+             */
+            $cachedUserGroups = array();
+        });
+    }
+
+    /**
+     * Checks whether a given backend is used
+     *
+     * @param string $backendClass Full classname including complete namespace
+     * @return bool
+     */
+    public function isBackendUsed($backendClass) {
+        $backendClass = strtolower(ltrim($backendClass, '\\'));
+
+        foreach ($this->backends as $backend) {
+            if (strtolower(get_class($backend)) === $backendClass) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * @param \OCP\GroupInterface $backend
+     */
+    public function addBackend($backend) {
+        $this->backends[] = $backend;
+        $this->clearCaches();
+    }
+
+    public function clearBackends() {
+        $this->backends = array();
+        $this->clearCaches();
+    }
+
+    /**
+     * Get the active backends
+     * @return \OCP\GroupInterface[]
+     */
+    public function getBackends() {
+        return $this->backends;
+    }
+
+
+    protected function clearCaches() {
+        $this->cachedGroups = array();
+        $this->cachedUserGroups = array();
+    }
+
+    /**
+     * @param string $gid
+     * @return \OC\Group\Group
+     */
+    public function get($gid) {
+        if (isset($this->cachedGroups[$gid])) {
+            return $this->cachedGroups[$gid];
+        }
+        return $this->getGroupObject($gid);
+    }
+
+    /**
+     * @param string $gid
+     * @param string $displayName
+     * @return \OCP\IGroup
+     */
+    protected function getGroupObject($gid, $displayName = null) {
+        $backends = array();
+        foreach ($this->backends as $backend) {
+            if ($backend->implementsActions(\OC\Group\Backend::GROUP_DETAILS)) {
+                $groupData = $backend->getGroupDetails($gid);
+                if (is_array($groupData)) {
+                    // take the display name from the first backend that has a non-null one
+                    if (is_null($displayName) && isset($groupData['displayName'])) {
+                        $displayName = $groupData['displayName'];
+                    }
+                    $backends[] = $backend;
+                }
+            } else if ($backend->groupExists($gid)) {
+                $backends[] = $backend;
+            }
+        }
+        if (count($backends) === 0) {
+            return null;
+        }
+        $this->cachedGroups[$gid] = new Group($gid, $backends, $this->userManager, $this, $displayName);
+        return $this->cachedGroups[$gid];
+    }
+
+    /**
+     * @param string $gid
+     * @return bool
+     */
+    public function groupExists($gid) {
+        return $this->get($gid) instanceof IGroup;
+    }
+
+    /**
+     * @param string $gid
+     * @return \OC\Group\Group
+     */
+    public function createGroup($gid) {
+        if ($gid === '' || $gid === null) {
+            return false;
+        } else if (trim(strtolower($gid)) === 'admin' && $this->get('admin')) {
+            return $this->get('admin');
+        } else if ($group = $this->get($gid)) {
+            return $group;
+        } else {
+            $this->emit('\OC\Group', 'preCreate', array($gid));
+            foreach ($this->backends as $backend) {
+                if ($backend->implementsActions(\OC\Group\Backend::CREATE_GROUP)) {
+                    $backend->createGroup($gid);
+                    $group = $this->getGroupObject($gid);
+                    $this->emit('\OC\Group', 'postCreate', array($group));
+                    return $group;
+                }
+            }
+            return null;
+        }
+    }
+
+    /**
+     * @param string $search
+     * @param int $limit
+     * @param int $offset
+     * @return \OC\Group\Group[]
+     */
+    public function search($search, $limit = null, $offset = null) {
+        $groups = array();
+        foreach ($this->backends as $backend) {
+            $groupIds = $backend->getGroups($search, $limit, $offset);
+            foreach ($groupIds as $groupId) {
+                $aGroup = $this->get($groupId);
+                if ($aGroup instanceof IGroup) {
+                    $groups[$groupId] = $aGroup;
+                } else {
+                    $this->logger->debug('Group "' . $groupId . '" was returned by search but not found through direct access', ['app' => 'core']);
+                }
+            }
+            if (!is_null($limit) and $limit <= 0) {
+                return array_values($groups);
+            }
+        }
+        return array_values($groups);
+    }
+
+    /**
+     * @param IUser|null $user
+     * @return \OC\Group\Group[]
+     */
+    public function getUserGroups(IUser $user= null) {
+        if (!$user instanceof IUser) {
+            return [];
+        }
+        return $this->getUserIdGroups($user->getUID());
+    }
+
+    /**
+     * @param string $uid the user id
+     * @return \OC\Group\Group[]
+     */
+    public function getUserIdGroups($uid) {
+        if (isset($this->cachedUserGroups[$uid])) {
+            return $this->cachedUserGroups[$uid];
+        }
+        $groups = array();
+        foreach ($this->backends as $backend) {
+            $groupIds = $backend->getUserGroups($uid);
+            if (is_array($groupIds)) {
+                foreach ($groupIds as $groupId) {
+                    $aGroup = $this->get($groupId);
+                    if ($aGroup instanceof IGroup) {
+                        $groups[$groupId] = $aGroup;
+                    } else {
+                        $this->logger->debug('User "' . $uid . '" belongs to deleted group: "' . $groupId . '"', ['app' => 'core']);
+                    }
+                }
+            }
+        }
+        $this->cachedUserGroups[$uid] = $groups;
+        return $this->cachedUserGroups[$uid];
+    }
+
+    /**
+     * Checks if a userId is in the admin group
+     * @param string $userId
+     * @return bool if admin
+     */
+    public function isAdmin($userId) {
+        foreach ($this->backends as $backend) {
+            if ($backend->implementsActions(\OC\Group\Backend::IS_ADMIN) && $backend->isAdmin($userId)) {
+                return true;
+            }
+        }
+        return $this->isInGroup($userId, 'admin');
+    }
+
+    /**
+     * Checks if a userId is in a group
+     * @param string $userId
+     * @param string $group
+     * @return bool if in group
+     */
+    public function isInGroup($userId, $group) {
+        return array_key_exists($group, $this->getUserIdGroups($userId));
+    }
+
+    /**
+     * get a list of group ids for a user
+     * @param IUser $user
+     * @return array with group ids
+     */
+    public function getUserGroupIds(IUser $user) {
+        return array_map(function($value) {
+            return (string) $value;
+        }, array_keys($this->getUserGroups($user)));
+    }
+
+    /**
+     * get an array of groupid and displayName for a user
+     * @param IUser $user
+     * @return array ['displayName' => displayname]
+     */
+    public function getUserGroupNames(IUser $user) {
+        return array_map(function($group) {
+            return array('displayName' => $group->getDisplayName());
+        }, $this->getUserGroups($user));
+    }
+
+    /**
+     * get a list of all display names in a group
+     * @param string $gid
+     * @param string $search
+     * @param int $limit
+     * @param int $offset
+     * @return array an array of display names (value) and user ids (key)
+     */
+    public function displayNamesInGroup($gid, $search = '', $limit = -1, $offset = 0) {
+        $group = $this->get($gid);
+        if(is_null($group)) {
+            return array();
+        }
+
+        $search = trim($search);
+        $groupUsers = array();
+
+        if(!empty($search)) {
+            // only user backends have the capability to do a complex search for users
+            $searchOffset = 0;
+            $searchLimit = $limit * 100;
+            if($limit === -1) {
+                $searchLimit = 500;
+            }
+
+            do {
+                $filteredUsers = $this->userManager->searchDisplayName($search, $searchLimit, $searchOffset);
+                foreach($filteredUsers as $filteredUser) {
+                    if($group->inGroup($filteredUser)) {
+                        $groupUsers[]= $filteredUser;
+                    }
+                }
+                $searchOffset += $searchLimit;
+            } while(count($groupUsers) < $searchLimit+$offset && count($filteredUsers) >= $searchLimit);
+
+            if($limit === -1) {
+                $groupUsers = array_slice($groupUsers, $offset);
+            } else {
+                $groupUsers = array_slice($groupUsers, $offset, $limit);
+            }
+        } else {
+            $groupUsers = $group->searchUsers('', $limit, $offset);
+        }
+
+        $matchingUsers = array();
+        foreach($groupUsers as $groupUser) {
+            $matchingUsers[$groupUser->getUID()] = $groupUser->getDisplayName();
+        }
+        return $matchingUsers;
+    }
+
+    /**
+     * @return \OC\SubAdmin
+     */
+    public function getSubAdmin() {
+        if (!$this->subAdmin) {
+            $this->subAdmin = new \OC\SubAdmin(
+                $this->userManager,
+                $this,
+                \OC::$server->getDatabaseConnection()
+            );
+        }
+
+        return $this->subAdmin;
+    }
 }