nextcloud / server

apps/federatedfilesharing/lib/FederatedShareProvider.php

Indentation +1057 added lines, -1057 removed lines

@@ -58,1071 +58,1071 @@
  * @package OCA\FederatedFileSharing
  */
 class FederatedShareProvider implements IShareProvider {
-	public const SHARE_TYPE_REMOTE = 6;
-
-	/** @var IDBConnection */
-	private $dbConnection;
-
-	/** @var AddressHandler */
-	private $addressHandler;
-
-	/** @var Notifications */
-	private $notifications;
-
-	/** @var TokenHandler */
-	private $tokenHandler;
-
-	/** @var IL10N */
-	private $l;
-
-	/** @var ILogger */
-	private $logger;
-
-	/** @var IRootFolder */
-	private $rootFolder;
-
-	/** @var IConfig */
-	private $config;
-
-	/** @var string */
-	private $externalShareTable = 'share_external';
-
-	/** @var IUserManager */
-	private $userManager;
-
-	/** @var ICloudIdManager */
-	private $cloudIdManager;
-
-	/** @var \OCP\GlobalScale\IConfig */
-	private $gsConfig;
-
-	/** @var ICloudFederationProviderManager */
-	private $cloudFederationProviderManager;
-
-	/** @var array list of supported share types */
-	private $supportedShareType = [IShare::TYPE_REMOTE_GROUP, IShare::TYPE_REMOTE, IShare::TYPE_CIRCLE];
-
-	/**
-	 * DefaultShareProvider constructor.
-	 *
-	 * @param IDBConnection $connection
-	 * @param AddressHandler $addressHandler
-	 * @param Notifications $notifications
-	 * @param TokenHandler $tokenHandler
-	 * @param IL10N $l10n
-	 * @param ILogger $logger
-	 * @param IRootFolder $rootFolder
-	 * @param IConfig $config
-	 * @param IUserManager $userManager
-	 * @param ICloudIdManager $cloudIdManager
-	 * @param \OCP\GlobalScale\IConfig $globalScaleConfig
-	 * @param ICloudFederationProviderManager $cloudFederationProviderManager
-	 */
-	public function __construct(
-			IDBConnection $connection,
-			AddressHandler $addressHandler,
-			Notifications $notifications,
-			TokenHandler $tokenHandler,
-			IL10N $l10n,
-			ILogger $logger,
-			IRootFolder $rootFolder,
-			IConfig $config,
-			IUserManager $userManager,
-			ICloudIdManager $cloudIdManager,
-			\OCP\GlobalScale\IConfig $globalScaleConfig,
-			ICloudFederationProviderManager $cloudFederationProviderManager
-	) {
-		$this->dbConnection = $connection;
-		$this->addressHandler = $addressHandler;
-		$this->notifications = $notifications;
-		$this->tokenHandler = $tokenHandler;
-		$this->l = $l10n;
-		$this->logger = $logger;
-		$this->rootFolder = $rootFolder;
-		$this->config = $config;
-		$this->userManager = $userManager;
-		$this->cloudIdManager = $cloudIdManager;
-		$this->gsConfig = $globalScaleConfig;
-		$this->cloudFederationProviderManager = $cloudFederationProviderManager;
-	}
-
-	/**
-	 * Return the identifier of this provider.
-	 *
-	 * @return string Containing only [a-zA-Z0-9]
-	 */
-	public function identifier() {
-		return 'ocFederatedSharing';
-	}
-
-	/**
-	 * Share a path
-	 *
-	 * @param IShare $share
-	 * @return IShare The share object
-	 * @throws ShareNotFound
-	 * @throws \Exception
-	 */
-	public function create(IShare $share) {
-		$shareWith = $share->getSharedWith();
-		$itemSource = $share->getNodeId();
-		$itemType = $share->getNodeType();
-		$permissions = $share->getPermissions();
-		$sharedBy = $share->getSharedBy();
-		$shareType = $share->getShareType();
-
-		if ($shareType === IShare::TYPE_REMOTE_GROUP &&
-			!$this->isOutgoingServer2serverGroupShareEnabled()
-		) {
-			$message = 'It is not allowed to send federated group shares from this server.';
-			$message_t = $this->l->t('It is not allowed to send federated group shares from this server.');
-			$this->logger->debug($message, ['app' => 'Federated File Sharing']);
-			throw new \Exception($message_t);
-		}
-
-		/*
+    public const SHARE_TYPE_REMOTE = 6;
+
+    /** @var IDBConnection */
+    private $dbConnection;
+
+    /** @var AddressHandler */
+    private $addressHandler;
+
+    /** @var Notifications */
+    private $notifications;
+
+    /** @var TokenHandler */
+    private $tokenHandler;
+
+    /** @var IL10N */
+    private $l;
+
+    /** @var ILogger */
+    private $logger;
+
+    /** @var IRootFolder */
+    private $rootFolder;
+
+    /** @var IConfig */
+    private $config;
+
+    /** @var string */
+    private $externalShareTable = 'share_external';
+
+    /** @var IUserManager */
+    private $userManager;
+
+    /** @var ICloudIdManager */
+    private $cloudIdManager;
+
+    /** @var \OCP\GlobalScale\IConfig */
+    private $gsConfig;
+
+    /** @var ICloudFederationProviderManager */
+    private $cloudFederationProviderManager;
+
+    /** @var array list of supported share types */
+    private $supportedShareType = [IShare::TYPE_REMOTE_GROUP, IShare::TYPE_REMOTE, IShare::TYPE_CIRCLE];
+
+    /**
+     * DefaultShareProvider constructor.
+     *
+     * @param IDBConnection $connection
+     * @param AddressHandler $addressHandler
+     * @param Notifications $notifications
+     * @param TokenHandler $tokenHandler
+     * @param IL10N $l10n
+     * @param ILogger $logger
+     * @param IRootFolder $rootFolder
+     * @param IConfig $config
+     * @param IUserManager $userManager
+     * @param ICloudIdManager $cloudIdManager
+     * @param \OCP\GlobalScale\IConfig $globalScaleConfig
+     * @param ICloudFederationProviderManager $cloudFederationProviderManager
+     */
+    public function __construct(
+            IDBConnection $connection,
+            AddressHandler $addressHandler,
+            Notifications $notifications,
+            TokenHandler $tokenHandler,
+            IL10N $l10n,
+            ILogger $logger,
+            IRootFolder $rootFolder,
+            IConfig $config,
+            IUserManager $userManager,
+            ICloudIdManager $cloudIdManager,
+            \OCP\GlobalScale\IConfig $globalScaleConfig,
+            ICloudFederationProviderManager $cloudFederationProviderManager
+    ) {
+        $this->dbConnection = $connection;
+        $this->addressHandler = $addressHandler;
+        $this->notifications = $notifications;
+        $this->tokenHandler = $tokenHandler;
+        $this->l = $l10n;
+        $this->logger = $logger;
+        $this->rootFolder = $rootFolder;
+        $this->config = $config;
+        $this->userManager = $userManager;
+        $this->cloudIdManager = $cloudIdManager;
+        $this->gsConfig = $globalScaleConfig;
+        $this->cloudFederationProviderManager = $cloudFederationProviderManager;
+    }
+
+    /**
+     * Return the identifier of this provider.
+     *
+     * @return string Containing only [a-zA-Z0-9]
+     */
+    public function identifier() {
+        return 'ocFederatedSharing';
+    }
+
+    /**
+     * Share a path
+     *
+     * @param IShare $share
+     * @return IShare The share object
+     * @throws ShareNotFound
+     * @throws \Exception
+     */
+    public function create(IShare $share) {
+        $shareWith = $share->getSharedWith();
+        $itemSource = $share->getNodeId();
+        $itemType = $share->getNodeType();
+        $permissions = $share->getPermissions();
+        $sharedBy = $share->getSharedBy();
+        $shareType = $share->getShareType();
+
+        if ($shareType === IShare::TYPE_REMOTE_GROUP &&
+            !$this->isOutgoingServer2serverGroupShareEnabled()
+        ) {
+            $message = 'It is not allowed to send federated group shares from this server.';
+            $message_t = $this->l->t('It is not allowed to send federated group shares from this server.');
+            $this->logger->debug($message, ['app' => 'Federated File Sharing']);
+            throw new \Exception($message_t);
+        }
+
+        /*
 		 * Check if file is not already shared with the remote user
 		 */
-		$alreadyShared = $this->getSharedWith($shareWith, IShare::TYPE_REMOTE, $share->getNode(), 1, 0);
-		$alreadySharedGroup = $this->getSharedWith($shareWith, IShare::TYPE_REMOTE_GROUP, $share->getNode(), 1, 0);
-		if (!empty($alreadyShared) || !empty($alreadySharedGroup)) {
-			$message = 'Sharing %1$s failed, because this item is already shared with %2$s';
-			$message_t = $this->l->t('Sharing %1$s failed, because this item is already shared with %2$s', [$share->getNode()->getName(), $shareWith]);
-			$this->logger->debug(sprintf($message, $share->getNode()->getName(), $shareWith), ['app' => 'Federated File Sharing']);
-			throw new \Exception($message_t);
-		}
-
-
-		// don't allow federated shares if source and target server are the same
-		$cloudId = $this->cloudIdManager->resolveCloudId($shareWith);
-		$currentServer = $this->addressHandler->generateRemoteURL();
-		$currentUser = $sharedBy;
-		if ($this->addressHandler->compareAddresses($cloudId->getUser(), $cloudId->getRemote(), $currentUser, $currentServer)) {
-			$message = 'Not allowed to create a federated share with the same user.';
-			$message_t = $this->l->t('Not allowed to create a federated share with the same user');
-			$this->logger->debug($message, ['app' => 'Federated File Sharing']);
-			throw new \Exception($message_t);
-		}
-
-
-		$share->setSharedWith($cloudId->getId());
-
-		try {
-			$remoteShare = $this->getShareFromExternalShareTable($share);
-		} catch (ShareNotFound $e) {
-			$remoteShare = null;
-		}
-
-		if ($remoteShare) {
-			try {
-				$ownerCloudId = $this->cloudIdManager->getCloudId($remoteShare['owner'], $remoteShare['remote']);
-				$shareId = $this->addShareToDB($itemSource, $itemType, $shareWith, $sharedBy, $ownerCloudId->getId(), $permissions, 'tmp_token_' . time(), $shareType);
-				$share->setId($shareId);
-				list($token, $remoteId) = $this->askOwnerToReShare($shareWith, $share, $shareId);
-				// remote share was create successfully if we get a valid token as return
-				$send = is_string($token) && $token !== '';
-			} catch (\Exception $e) {
-				// fall back to old re-share behavior if the remote server
-				// doesn't support flat re-shares (was introduced with Nextcloud 9.1)
-				$this->removeShareFromTable($share);
-				$shareId = $this->createFederatedShare($share);
-			}
-			if ($send) {
-				$this->updateSuccessfulReshare($shareId, $token);
-				$this->storeRemoteId($shareId, $remoteId);
-			} else {
-				$this->removeShareFromTable($share);
-				$message_t = $this->l->t('File is already shared with %s', [$shareWith]);
-				throw new \Exception($message_t);
-			}
-		} else {
-			$shareId = $this->createFederatedShare($share);
-		}
-
-		$data = $this->getRawShare($shareId);
-		return $this->createShareObject($data);
-	}
-
-	/**
-	 * create federated share and inform the recipient
-	 *
-	 * @param IShare $share
-	 * @return int
-	 * @throws ShareNotFound
-	 * @throws \Exception
-	 */
-	protected function createFederatedShare(IShare $share) {
-		$token = $this->tokenHandler->generateToken();
-		$shareId = $this->addShareToDB(
-			$share->getNodeId(),
-			$share->getNodeType(),
-			$share->getSharedWith(),
-			$share->getSharedBy(),
-			$share->getShareOwner(),
-			$share->getPermissions(),
-			$token,
-			$share->getShareType()
-		);
-
-		$failure = false;
-
-		try {
-			$sharedByFederatedId = $share->getSharedBy();
-			if ($this->userManager->userExists($sharedByFederatedId)) {
-				$cloudId = $this->cloudIdManager->getCloudId($sharedByFederatedId, $this->addressHandler->generateRemoteURL());
-				$sharedByFederatedId = $cloudId->getId();
-			}
-			$ownerCloudId = $this->cloudIdManager->getCloudId($share->getShareOwner(), $this->addressHandler->generateRemoteURL());
-			$send = $this->notifications->sendRemoteShare(
-				$token,
-				$share->getSharedWith(),
-				$share->getNode()->getName(),
-				$shareId,
-				$share->getShareOwner(),
-				$ownerCloudId->getId(),
-				$share->getSharedBy(),
-				$sharedByFederatedId,
-				$share->getShareType()
-			);
-
-			if ($send === false) {
-				$failure = true;
-			}
-		} catch (\Exception $e) {
-			$this->logger->logException($e, [
-				'message' => 'Failed to notify remote server of federated share, removing share.',
-				'level' => ILogger::ERROR,
-				'app' => 'federatedfilesharing',
-			]);
-			$failure = true;
-		}
-
-		if ($failure) {
-			$this->removeShareFromTableById($shareId);
-			$message_t = $this->l->t('Sharing %1$s failed, could not find %2$s, maybe the server is currently unreachable or uses a self-signed certificate.',
-				[$share->getNode()->getName(), $share->getSharedWith()]);
-			throw new \Exception($message_t);
-		}
-
-		return $shareId;
-	}
-
-	/**
-	 * @param string $shareWith
-	 * @param IShare $share
-	 * @param string $shareId internal share Id
-	 * @return array
-	 * @throws \Exception
-	 */
-	protected function askOwnerToReShare($shareWith, IShare $share, $shareId) {
-		$remoteShare = $this->getShareFromExternalShareTable($share);
-		$token = $remoteShare['share_token'];
-		$remoteId = $remoteShare['remote_id'];
-		$remote = $remoteShare['remote'];
-
-		list($token, $remoteId) = $this->notifications->requestReShare(
-			$token,
-			$remoteId,
-			$shareId,
-			$remote,
-			$shareWith,
-			$share->getPermissions(),
-			$share->getNode()->getName()
-		);
-
-		return [$token, $remoteId];
-	}
-
-	/**
-	 * get federated share from the share_external table but exclude mounted link shares
-	 *
-	 * @param IShare $share
-	 * @return array
-	 * @throws ShareNotFound
-	 */
-	protected function getShareFromExternalShareTable(IShare $share) {
-		$query = $this->dbConnection->getQueryBuilder();
-		$query->select('*')->from($this->externalShareTable)
-			->where($query->expr()->eq('user', $query->createNamedParameter($share->getShareOwner())))
-			->andWhere($query->expr()->eq('mountpoint', $query->createNamedParameter($share->getTarget())));
-		$result = $query->execute()->fetchAll();
-
-		if (isset($result[0]) && (int)$result[0]['remote_id'] > 0) {
-			return $result[0];
-		}
-
-		throw new ShareNotFound('share not found in share_external table');
-	}
-
-	/**
-	 * add share to the database and return the ID
-	 *
-	 * @param int $itemSource
-	 * @param string $itemType
-	 * @param string $shareWith
-	 * @param string $sharedBy
-	 * @param string $uidOwner
-	 * @param int $permissions
-	 * @param string $token
-	 * @param int $shareType
-	 * @return int
-	 */
-	private function addShareToDB($itemSource, $itemType, $shareWith, $sharedBy, $uidOwner, $permissions, $token, $shareType) {
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->insert('share')
-			->setValue('share_type', $qb->createNamedParameter($shareType))
-			->setValue('item_type', $qb->createNamedParameter($itemType))
-			->setValue('item_source', $qb->createNamedParameter($itemSource))
-			->setValue('file_source', $qb->createNamedParameter($itemSource))
-			->setValue('share_with', $qb->createNamedParameter($shareWith))
-			->setValue('uid_owner', $qb->createNamedParameter($uidOwner))
-			->setValue('uid_initiator', $qb->createNamedParameter($sharedBy))
-			->setValue('permissions', $qb->createNamedParameter($permissions))
-			->setValue('token', $qb->createNamedParameter($token))
-			->setValue('stime', $qb->createNamedParameter(time()));
-
-		/*
+        $alreadyShared = $this->getSharedWith($shareWith, IShare::TYPE_REMOTE, $share->getNode(), 1, 0);
+        $alreadySharedGroup = $this->getSharedWith($shareWith, IShare::TYPE_REMOTE_GROUP, $share->getNode(), 1, 0);
+        if (!empty($alreadyShared) || !empty($alreadySharedGroup)) {
+            $message = 'Sharing %1$s failed, because this item is already shared with %2$s';
+            $message_t = $this->l->t('Sharing %1$s failed, because this item is already shared with %2$s', [$share->getNode()->getName(), $shareWith]);
+            $this->logger->debug(sprintf($message, $share->getNode()->getName(), $shareWith), ['app' => 'Federated File Sharing']);
+            throw new \Exception($message_t);
+        }
+
+
+        // don't allow federated shares if source and target server are the same
+        $cloudId = $this->cloudIdManager->resolveCloudId($shareWith);
+        $currentServer = $this->addressHandler->generateRemoteURL();
+        $currentUser = $sharedBy;
+        if ($this->addressHandler->compareAddresses($cloudId->getUser(), $cloudId->getRemote(), $currentUser, $currentServer)) {
+            $message = 'Not allowed to create a federated share with the same user.';
+            $message_t = $this->l->t('Not allowed to create a federated share with the same user');
+            $this->logger->debug($message, ['app' => 'Federated File Sharing']);
+            throw new \Exception($message_t);
+        }
+
+
+        $share->setSharedWith($cloudId->getId());
+
+        try {
+            $remoteShare = $this->getShareFromExternalShareTable($share);
+        } catch (ShareNotFound $e) {
+            $remoteShare = null;
+        }
+
+        if ($remoteShare) {
+            try {
+                $ownerCloudId = $this->cloudIdManager->getCloudId($remoteShare['owner'], $remoteShare['remote']);
+                $shareId = $this->addShareToDB($itemSource, $itemType, $shareWith, $sharedBy, $ownerCloudId->getId(), $permissions, 'tmp_token_' . time(), $shareType);
+                $share->setId($shareId);
+                list($token, $remoteId) = $this->askOwnerToReShare($shareWith, $share, $shareId);
+                // remote share was create successfully if we get a valid token as return
+                $send = is_string($token) && $token !== '';
+            } catch (\Exception $e) {
+                // fall back to old re-share behavior if the remote server
+                // doesn't support flat re-shares (was introduced with Nextcloud 9.1)
+                $this->removeShareFromTable($share);
+                $shareId = $this->createFederatedShare($share);
+            }
+            if ($send) {
+                $this->updateSuccessfulReshare($shareId, $token);
+                $this->storeRemoteId($shareId, $remoteId);
+            } else {
+                $this->removeShareFromTable($share);
+                $message_t = $this->l->t('File is already shared with %s', [$shareWith]);
+                throw new \Exception($message_t);
+            }
+        } else {
+            $shareId = $this->createFederatedShare($share);
+        }
+
+        $data = $this->getRawShare($shareId);
+        return $this->createShareObject($data);
+    }
+
+    /**
+     * create federated share and inform the recipient
+     *
+     * @param IShare $share
+     * @return int
+     * @throws ShareNotFound
+     * @throws \Exception
+     */
+    protected function createFederatedShare(IShare $share) {
+        $token = $this->tokenHandler->generateToken();
+        $shareId = $this->addShareToDB(
+            $share->getNodeId(),
+            $share->getNodeType(),
+            $share->getSharedWith(),
+            $share->getSharedBy(),
+            $share->getShareOwner(),
+            $share->getPermissions(),
+            $token,
+            $share->getShareType()
+        );
+
+        $failure = false;
+
+        try {
+            $sharedByFederatedId = $share->getSharedBy();
+            if ($this->userManager->userExists($sharedByFederatedId)) {
+                $cloudId = $this->cloudIdManager->getCloudId($sharedByFederatedId, $this->addressHandler->generateRemoteURL());
+                $sharedByFederatedId = $cloudId->getId();
+            }
+            $ownerCloudId = $this->cloudIdManager->getCloudId($share->getShareOwner(), $this->addressHandler->generateRemoteURL());
+            $send = $this->notifications->sendRemoteShare(
+                $token,
+                $share->getSharedWith(),
+                $share->getNode()->getName(),
+                $shareId,
+                $share->getShareOwner(),
+                $ownerCloudId->getId(),
+                $share->getSharedBy(),
+                $sharedByFederatedId,
+                $share->getShareType()
+            );
+
+            if ($send === false) {
+                $failure = true;
+            }
+        } catch (\Exception $e) {
+            $this->logger->logException($e, [
+                'message' => 'Failed to notify remote server of federated share, removing share.',
+                'level' => ILogger::ERROR,
+                'app' => 'federatedfilesharing',
+            ]);
+            $failure = true;
+        }
+
+        if ($failure) {
+            $this->removeShareFromTableById($shareId);
+            $message_t = $this->l->t('Sharing %1$s failed, could not find %2$s, maybe the server is currently unreachable or uses a self-signed certificate.',
+                [$share->getNode()->getName(), $share->getSharedWith()]);
+            throw new \Exception($message_t);
+        }
+
+        return $shareId;
+    }
+
+    /**
+     * @param string $shareWith
+     * @param IShare $share
+     * @param string $shareId internal share Id
+     * @return array
+     * @throws \Exception
+     */
+    protected function askOwnerToReShare($shareWith, IShare $share, $shareId) {
+        $remoteShare = $this->getShareFromExternalShareTable($share);
+        $token = $remoteShare['share_token'];
+        $remoteId = $remoteShare['remote_id'];
+        $remote = $remoteShare['remote'];
+
+        list($token, $remoteId) = $this->notifications->requestReShare(
+            $token,
+            $remoteId,
+            $shareId,
+            $remote,
+            $shareWith,
+            $share->getPermissions(),
+            $share->getNode()->getName()
+        );
+
+        return [$token, $remoteId];
+    }
+
+    /**
+     * get federated share from the share_external table but exclude mounted link shares
+     *
+     * @param IShare $share
+     * @return array
+     * @throws ShareNotFound
+     */
+    protected function getShareFromExternalShareTable(IShare $share) {
+        $query = $this->dbConnection->getQueryBuilder();
+        $query->select('*')->from($this->externalShareTable)
+            ->where($query->expr()->eq('user', $query->createNamedParameter($share->getShareOwner())))
+            ->andWhere($query->expr()->eq('mountpoint', $query->createNamedParameter($share->getTarget())));
+        $result = $query->execute()->fetchAll();
+
+        if (isset($result[0]) && (int)$result[0]['remote_id'] > 0) {
+            return $result[0];
+        }
+
+        throw new ShareNotFound('share not found in share_external table');
+    }
+
+    /**
+     * add share to the database and return the ID
+     *
+     * @param int $itemSource
+     * @param string $itemType
+     * @param string $shareWith
+     * @param string $sharedBy
+     * @param string $uidOwner
+     * @param int $permissions
+     * @param string $token
+     * @param int $shareType
+     * @return int
+     */
+    private function addShareToDB($itemSource, $itemType, $shareWith, $sharedBy, $uidOwner, $permissions, $token, $shareType) {
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->insert('share')
+            ->setValue('share_type', $qb->createNamedParameter($shareType))
+            ->setValue('item_type', $qb->createNamedParameter($itemType))
+            ->setValue('item_source', $qb->createNamedParameter($itemSource))
+            ->setValue('file_source', $qb->createNamedParameter($itemSource))
+            ->setValue('share_with', $qb->createNamedParameter($shareWith))
+            ->setValue('uid_owner', $qb->createNamedParameter($uidOwner))
+            ->setValue('uid_initiator', $qb->createNamedParameter($sharedBy))
+            ->setValue('permissions', $qb->createNamedParameter($permissions))
+            ->setValue('token', $qb->createNamedParameter($token))
+            ->setValue('stime', $qb->createNamedParameter(time()));
+
+        /*
 		 * Added to fix https://github.com/owncloud/core/issues/22215
 		 * Can be removed once we get rid of ajax/share.php
 		 */
-		$qb->setValue('file_target', $qb->createNamedParameter(''));
-
-		$qb->execute();
-		$id = $qb->getLastInsertId();
-
-		return (int)$id;
-	}
-
-	/**
-	 * Update a share
-	 *
-	 * @param IShare $share
-	 * @return IShare The share object
-	 */
-	public function update(IShare $share) {
-		/*
+        $qb->setValue('file_target', $qb->createNamedParameter(''));
+
+        $qb->execute();
+        $id = $qb->getLastInsertId();
+
+        return (int)$id;
+    }
+
+    /**
+     * Update a share
+     *
+     * @param IShare $share
+     * @return IShare The share object
+     */
+    public function update(IShare $share) {
+        /*
 		 * We allow updating the permissions of federated shares
 		 */
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->update('share')
-				->where($qb->expr()->eq('id', $qb->createNamedParameter($share->getId())))
-				->set('permissions', $qb->createNamedParameter($share->getPermissions()))
-				->set('uid_owner', $qb->createNamedParameter($share->getShareOwner()))
-				->set('uid_initiator', $qb->createNamedParameter($share->getSharedBy()))
-				->execute();
-
-		// send the updated permission to the owner/initiator, if they are not the same
-		if ($share->getShareOwner() !== $share->getSharedBy()) {
-			$this->sendPermissionUpdate($share);
-		}
-
-		return $share;
-	}
-
-	/**
-	 * send the updated permission to the owner/initiator, if they are not the same
-	 *
-	 * @param IShare $share
-	 * @throws ShareNotFound
-	 * @throws \OC\HintException
-	 */
-	protected function sendPermissionUpdate(IShare $share) {
-		$remoteId = $this->getRemoteId($share);
-		// if the local user is the owner we send the permission change to the initiator
-		if ($this->userManager->userExists($share->getShareOwner())) {
-			list(, $remote) = $this->addressHandler->splitUserRemote($share->getSharedBy());
-		} else { // ... if not we send the permission change to the owner
-			list(, $remote) = $this->addressHandler->splitUserRemote($share->getShareOwner());
-		}
-		$this->notifications->sendPermissionChange($remote, $remoteId, $share->getToken(), $share->getPermissions());
-	}
-
-
-	/**
-	 * update successful reShare with the correct token
-	 *
-	 * @param int $shareId
-	 * @param string $token
-	 */
-	protected function updateSuccessfulReShare($shareId, $token) {
-		$query = $this->dbConnection->getQueryBuilder();
-		$query->update('share')
-			->where($query->expr()->eq('id', $query->createNamedParameter($shareId)))
-			->set('token', $query->createNamedParameter($token))
-			->execute();
-	}
-
-	/**
-	 * store remote ID in federated reShare table
-	 *
-	 * @param $shareId
-	 * @param $remoteId
-	 */
-	public function storeRemoteId($shareId, $remoteId) {
-		$query = $this->dbConnection->getQueryBuilder();
-		$query->insert('federated_reshares')
-			->values(
-				[
-					'share_id' =>  $query->createNamedParameter($shareId),
-					'remote_id' => $query->createNamedParameter($remoteId),
-				]
-			);
-		$query->execute();
-	}
-
-	/**
-	 * get share ID on remote server for federated re-shares
-	 *
-	 * @param IShare $share
-	 * @return int
-	 * @throws ShareNotFound
-	 */
-	public function getRemoteId(IShare $share) {
-		$query = $this->dbConnection->getQueryBuilder();
-		$query->select('remote_id')->from('federated_reshares')
-			->where($query->expr()->eq('share_id', $query->createNamedParameter((int)$share->getId())));
-		$data = $query->execute()->fetch();
-
-		if (!is_array($data) || !isset($data['remote_id'])) {
-			throw new ShareNotFound();
-		}
-
-		return (int)$data['remote_id'];
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function move(IShare $share, $recipient) {
-		/*
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->update('share')
+                ->where($qb->expr()->eq('id', $qb->createNamedParameter($share->getId())))
+                ->set('permissions', $qb->createNamedParameter($share->getPermissions()))
+                ->set('uid_owner', $qb->createNamedParameter($share->getShareOwner()))
+                ->set('uid_initiator', $qb->createNamedParameter($share->getSharedBy()))
+                ->execute();
+
+        // send the updated permission to the owner/initiator, if they are not the same
+        if ($share->getShareOwner() !== $share->getSharedBy()) {
+            $this->sendPermissionUpdate($share);
+        }
+
+        return $share;
+    }
+
+    /**
+     * send the updated permission to the owner/initiator, if they are not the same
+     *
+     * @param IShare $share
+     * @throws ShareNotFound
+     * @throws \OC\HintException
+     */
+    protected function sendPermissionUpdate(IShare $share) {
+        $remoteId = $this->getRemoteId($share);
+        // if the local user is the owner we send the permission change to the initiator
+        if ($this->userManager->userExists($share->getShareOwner())) {
+            list(, $remote) = $this->addressHandler->splitUserRemote($share->getSharedBy());
+        } else { // ... if not we send the permission change to the owner
+            list(, $remote) = $this->addressHandler->splitUserRemote($share->getShareOwner());
+        }
+        $this->notifications->sendPermissionChange($remote, $remoteId, $share->getToken(), $share->getPermissions());
+    }
+
+
+    /**
+     * update successful reShare with the correct token
+     *
+     * @param int $shareId
+     * @param string $token
+     */
+    protected function updateSuccessfulReShare($shareId, $token) {
+        $query = $this->dbConnection->getQueryBuilder();
+        $query->update('share')
+            ->where($query->expr()->eq('id', $query->createNamedParameter($shareId)))
+            ->set('token', $query->createNamedParameter($token))
+            ->execute();
+    }
+
+    /**
+     * store remote ID in federated reShare table
+     *
+     * @param $shareId
+     * @param $remoteId
+     */
+    public function storeRemoteId($shareId, $remoteId) {
+        $query = $this->dbConnection->getQueryBuilder();
+        $query->insert('federated_reshares')
+            ->values(
+                [
+                    'share_id' =>  $query->createNamedParameter($shareId),
+                    'remote_id' => $query->createNamedParameter($remoteId),
+                ]
+            );
+        $query->execute();
+    }
+
+    /**
+     * get share ID on remote server for federated re-shares
+     *
+     * @param IShare $share
+     * @return int
+     * @throws ShareNotFound
+     */
+    public function getRemoteId(IShare $share) {
+        $query = $this->dbConnection->getQueryBuilder();
+        $query->select('remote_id')->from('federated_reshares')
+            ->where($query->expr()->eq('share_id', $query->createNamedParameter((int)$share->getId())));
+        $data = $query->execute()->fetch();
+
+        if (!is_array($data) || !isset($data['remote_id'])) {
+            throw new ShareNotFound();
+        }
+
+        return (int)$data['remote_id'];
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function move(IShare $share, $recipient) {
+        /*
 		 * This function does nothing yet as it is just for outgoing
 		 * federated shares.
 		 */
-		return $share;
-	}
-
-	/**
-	 * Get all children of this share
-	 *
-	 * @param IShare $parent
-	 * @return IShare[]
-	 */
-	public function getChildren(IShare $parent) {
-		$children = [];
-
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('*')
-			->from('share')
-			->where($qb->expr()->eq('parent', $qb->createNamedParameter($parent->getId())))
-			->andWhere($qb->expr()->in('share_type', $qb->createNamedParameter($this->supportedShareType, IQueryBuilder::PARAM_INT_ARRAY)))
-			->orderBy('id');
-
-		$cursor = $qb->execute();
-		while ($data = $cursor->fetch()) {
-			$children[] = $this->createShareObject($data);
-		}
-		$cursor->closeCursor();
-
-		return $children;
-	}
-
-	/**
-	 * Delete a share (owner unShares the file)
-	 *
-	 * @param IShare $share
-	 * @throws ShareNotFound
-	 * @throws \OC\HintException
-	 */
-	public function delete(IShare $share) {
-		list(, $remote) = $this->addressHandler->splitUserRemote($share->getSharedWith());
-
-		// if the local user is the owner we can send the unShare request directly...
-		if ($this->userManager->userExists($share->getShareOwner())) {
-			$this->notifications->sendRemoteUnShare($remote, $share->getId(), $share->getToken());
-			$this->revokeShare($share, true);
-		} else { // ... if not we need to correct ID for the unShare request
-			$remoteId = $this->getRemoteId($share);
-			$this->notifications->sendRemoteUnShare($remote, $remoteId, $share->getToken());
-			$this->revokeShare($share, false);
-		}
-
-		// only remove the share when all messages are send to not lose information
-		// about the share to early
-		$this->removeShareFromTable($share);
-	}
-
-	/**
-	 * in case of a re-share we need to send the other use (initiator or owner)
-	 * a message that the file was unshared
-	 *
-	 * @param IShare $share
-	 * @param bool $isOwner the user can either be the owner or the user who re-sahred it
-	 * @throws ShareNotFound
-	 * @throws \OC\HintException
-	 */
-	protected function revokeShare($share, $isOwner) {
-		if ($this->userManager->userExists($share->getShareOwner()) && $this->userManager->userExists($share->getSharedBy())) {
-			// If both the owner and the initiator of the share are local users we don't have to notify anybody else
-			return;
-		}
-
-		// also send a unShare request to the initiator, if this is a different user than the owner
-		if ($share->getShareOwner() !== $share->getSharedBy()) {
-			if ($isOwner) {
-				list(, $remote) = $this->addressHandler->splitUserRemote($share->getSharedBy());
-			} else {
-				list(, $remote) = $this->addressHandler->splitUserRemote($share->getShareOwner());
-			}
-			$remoteId = $this->getRemoteId($share);
-			$this->notifications->sendRevokeShare($remote, $remoteId, $share->getToken());
-		}
-	}
-
-	/**
-	 * remove share from table
-	 *
-	 * @param IShare $share
-	 */
-	public function removeShareFromTable(IShare $share) {
-		$this->removeShareFromTableById($share->getId());
-	}
-
-	/**
-	 * remove share from table
-	 *
-	 * @param string $shareId
-	 */
-	private function removeShareFromTableById($shareId) {
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->delete('share')
-			->where($qb->expr()->eq('id', $qb->createNamedParameter($shareId)))
-			->andWhere($qb->expr()->neq('share_type', $qb->createNamedParameter(IShare::TYPE_CIRCLE)));
-		$qb->execute();
-
-		$qb->delete('federated_reshares')
-			->where($qb->expr()->eq('share_id', $qb->createNamedParameter($shareId)));
-		$qb->execute();
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function deleteFromSelf(IShare $share, $recipient) {
-		// nothing to do here. Technically deleteFromSelf in the context of federated
-		// shares is a umount of an external storage. This is handled here
-		// apps/files_sharing/lib/external/manager.php
-		// TODO move this code over to this app
-	}
-
-	public function restore(IShare $share, string $recipient): IShare {
-		throw new GenericShareException('not implemented');
-	}
-
-
-	public function getSharesInFolder($userId, Folder $node, $reshares) {
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('*')
-			->from('share', 's')
-			->andWhere($qb->expr()->orX(
-				$qb->expr()->eq('item_type', $qb->createNamedParameter('file')),
-				$qb->expr()->eq('item_type', $qb->createNamedParameter('folder'))
-			))
-			->andWhere(
-				$qb->expr()->eq('share_type', $qb->createNamedParameter(IShare::TYPE_REMOTE))
-			);
-
-		/**
-		 * Reshares for this user are shares where they are the owner.
-		 */
-		if ($reshares === false) {
-			$qb->andWhere($qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId)));
-		} else {
-			$qb->andWhere(
-				$qb->expr()->orX(
-					$qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
-					$qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId))
-				)
-			);
-		}
-
-		$qb->innerJoin('s', 'filecache' ,'f', $qb->expr()->eq('s.file_source', 'f.fileid'));
-		$qb->andWhere($qb->expr()->eq('f.parent', $qb->createNamedParameter($node->getId())));
-
-		$qb->orderBy('id');
-
-		$cursor = $qb->execute();
-		$shares = [];
-		while ($data = $cursor->fetch()) {
-			$shares[$data['fileid']][] = $this->createShareObject($data);
-		}
-		$cursor->closeCursor();
-
-		return $shares;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function getSharesBy($userId, $shareType, $node, $reshares, $limit, $offset) {
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('*')
-			->from('share');
-
-		$qb->andWhere($qb->expr()->eq('share_type', $qb->createNamedParameter($shareType)));
-
-		/**
-		 * Reshares for this user are shares where they are the owner.
-		 */
-		if ($reshares === false) {
-			//Special case for old shares created via the web UI
-			$or1 = $qb->expr()->andX(
-				$qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
-				$qb->expr()->isNull('uid_initiator')
-			);
-
-			$qb->andWhere(
-				$qb->expr()->orX(
-					$qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId)),
-					$or1
-				)
-			);
-		} else {
-			$qb->andWhere(
-				$qb->expr()->orX(
-					$qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
-					$qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId))
-				)
-			);
-		}
-
-		if ($node !== null) {
-			$qb->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($node->getId())));
-		}
-
-		if ($limit !== -1) {
-			$qb->setMaxResults($limit);
-		}
-
-		$qb->setFirstResult($offset);
-		$qb->orderBy('id');
-
-		$cursor = $qb->execute();
-		$shares = [];
-		while ($data = $cursor->fetch()) {
-			$shares[] = $this->createShareObject($data);
-		}
-		$cursor->closeCursor();
-
-		return $shares;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function getShareById($id, $recipientId = null) {
-		$qb = $this->dbConnection->getQueryBuilder();
-
-		$qb->select('*')
-			->from('share')
-			->where($qb->expr()->eq('id', $qb->createNamedParameter($id)))
-			->andWhere($qb->expr()->in('share_type', $qb->createNamedParameter($this->supportedShareType, IQueryBuilder::PARAM_INT_ARRAY)));
-
-		$cursor = $qb->execute();
-		$data = $cursor->fetch();
-		$cursor->closeCursor();
-
-		if ($data === false) {
-			throw new ShareNotFound('Can not find share with ID: ' . $id);
-		}
-
-		try {
-			$share = $this->createShareObject($data);
-		} catch (InvalidShare $e) {
-			throw new ShareNotFound();
-		}
-
-		return $share;
-	}
-
-	/**
-	 * Get shares for a given path
-	 *
-	 * @param \OCP\Files\Node $path
-	 * @return IShare[]
-	 */
-	public function getSharesByPath(Node $path) {
-		$qb = $this->dbConnection->getQueryBuilder();
-
-		// get federated user shares
-		$cursor = $qb->select('*')
-			->from('share')
-			->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($path->getId())))
-			->andWhere($qb->expr()->in('share_type', $qb->createNamedParameter($this->supportedShareType, IQueryBuilder::PARAM_INT_ARRAY)))
-			->execute();
-
-		$shares = [];
-		while ($data = $cursor->fetch()) {
-			$shares[] = $this->createShareObject($data);
-		}
-		$cursor->closeCursor();
-
-		return $shares;
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function getSharedWith($userId, $shareType, $node, $limit, $offset) {
-		/** @var IShare[] $shares */
-		$shares = [];
-
-		//Get shares directly with this user
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('*')
-			->from('share');
-
-		// Order by id
-		$qb->orderBy('id');
-
-		// Set limit and offset
-		if ($limit !== -1) {
-			$qb->setMaxResults($limit);
-		}
-		$qb->setFirstResult($offset);
-
-		$qb->where($qb->expr()->in('share_type', $qb->createNamedParameter($this->supportedShareType, IQueryBuilder::PARAM_INT_ARRAY)));
-		$qb->andWhere($qb->expr()->eq('share_with', $qb->createNamedParameter($userId)));
-
-		// Filter by node if provided
-		if ($node !== null) {
-			$qb->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($node->getId())));
-		}
-
-		$cursor = $qb->execute();
-
-		while ($data = $cursor->fetch()) {
-			$shares[] = $this->createShareObject($data);
-		}
-		$cursor->closeCursor();
-
-
-		return $shares;
-	}
-
-	/**
-	 * Get a share by token
-	 *
-	 * @param string $token
-	 * @return IShare
-	 * @throws ShareNotFound
-	 */
-	public function getShareByToken($token) {
-		$qb = $this->dbConnection->getQueryBuilder();
-
-		$cursor = $qb->select('*')
-			->from('share')
-			->where($qb->expr()->in('share_type', $qb->createNamedParameter($this->supportedShareType, IQueryBuilder::PARAM_INT_ARRAY)))
-			->andWhere($qb->expr()->eq('token', $qb->createNamedParameter($token)))
-			->execute();
-
-		$data = $cursor->fetch();
-
-		if ($data === false) {
-			throw new ShareNotFound('Share not found', $this->l->t('Could not find share'));
-		}
-
-		try {
-			$share = $this->createShareObject($data);
-		} catch (InvalidShare $e) {
-			throw new ShareNotFound('Share not found', $this->l->t('Could not find share'));
-		}
-
-		return $share;
-	}
-
-	/**
-	 * get database row of a give share
-	 *
-	 * @param $id
-	 * @return array
-	 * @throws ShareNotFound
-	 */
-	private function getRawShare($id) {
-
-		// Now fetch the inserted share and create a complete share object
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('*')
-			->from('share')
-			->where($qb->expr()->eq('id', $qb->createNamedParameter($id)));
-
-		$cursor = $qb->execute();
-		$data = $cursor->fetch();
-		$cursor->closeCursor();
-
-		if ($data === false) {
-			throw new ShareNotFound;
-		}
-
-		return $data;
-	}
-
-	/**
-	 * Create a share object from an database row
-	 *
-	 * @param array $data
-	 * @return IShare
-	 * @throws InvalidShare
-	 * @throws ShareNotFound
-	 */
-	private function createShareObject($data) {
-		$share = new Share($this->rootFolder, $this->userManager);
-		$share->setId((int)$data['id'])
-			->setShareType((int)$data['share_type'])
-			->setPermissions((int)$data['permissions'])
-			->setTarget($data['file_target'])
-			->setMailSend((bool)$data['mail_send'])
-			->setToken($data['token']);
-
-		$shareTime = new \DateTime();
-		$shareTime->setTimestamp((int)$data['stime']);
-		$share->setShareTime($shareTime);
-		$share->setSharedWith($data['share_with']);
-
-		if ($data['uid_initiator'] !== null) {
-			$share->setShareOwner($data['uid_owner']);
-			$share->setSharedBy($data['uid_initiator']);
-		} else {
-			//OLD SHARE
-			$share->setSharedBy($data['uid_owner']);
-			$path = $this->getNode($share->getSharedBy(), (int)$data['file_source']);
-
-			$owner = $path->getOwner();
-			$share->setShareOwner($owner->getUID());
-		}
-
-		$share->setNodeId((int)$data['file_source']);
-		$share->setNodeType($data['item_type']);
-
-		$share->setProviderId($this->identifier());
-
-		return $share;
-	}
-
-	/**
-	 * Get the node with file $id for $user
-	 *
-	 * @param string $userId
-	 * @param int $id
-	 * @return \OCP\Files\File|\OCP\Files\Folder
-	 * @throws InvalidShare
-	 */
-	private function getNode($userId, $id) {
-		try {
-			$userFolder = $this->rootFolder->getUserFolder($userId);
-		} catch (NotFoundException $e) {
-			throw new InvalidShare();
-		}
-
-		$nodes = $userFolder->getById($id);
-
-		if (empty($nodes)) {
-			throw new InvalidShare();
-		}
-
-		return $nodes[0];
-	}
-
-	/**
-	 * A user is deleted from the system
-	 * So clean up the relevant shares.
-	 *
-	 * @param string $uid
-	 * @param int $shareType
-	 */
-	public function userDeleted($uid, $shareType) {
-		//TODO: probabaly a good idea to send unshare info to remote servers
-
-		$qb = $this->dbConnection->getQueryBuilder();
-
-		$qb->delete('share')
-			->where($qb->expr()->eq('share_type', $qb->createNamedParameter(IShare::TYPE_REMOTE)))
-			->andWhere($qb->expr()->eq('uid_owner', $qb->createNamedParameter($uid)))
-			->execute();
-	}
-
-	/**
-	 * This provider does not handle groups
-	 *
-	 * @param string $gid
-	 */
-	public function groupDeleted($gid) {
-		// We don't handle groups here
-	}
-
-	/**
-	 * This provider does not handle groups
-	 *
-	 * @param string $uid
-	 * @param string $gid
-	 */
-	public function userDeletedFromGroup($uid, $gid) {
-		// We don't handle groups here
-	}
-
-	/**
-	 * check if users from other Nextcloud instances are allowed to mount public links share by this instance
-	 *
-	 * @return bool
-	 */
-	public function isOutgoingServer2serverShareEnabled() {
-		if ($this->gsConfig->onlyInternalFederation()) {
-			return false;
-		}
-		$result = $this->config->getAppValue('files_sharing', 'outgoing_server2server_share_enabled', 'yes');
-		return ($result === 'yes');
-	}
-
-	/**
-	 * check if users are allowed to mount public links from other Nextclouds
-	 *
-	 * @return bool
-	 */
-	public function isIncomingServer2serverShareEnabled() {
-		if ($this->gsConfig->onlyInternalFederation()) {
-			return false;
-		}
-		$result = $this->config->getAppValue('files_sharing', 'incoming_server2server_share_enabled', 'yes');
-		return ($result === 'yes');
-	}
-
-
-	/**
-	 * check if users from other Nextcloud instances are allowed to send federated group shares
-	 *
-	 * @return bool
-	 */
-	public function isOutgoingServer2serverGroupShareEnabled() {
-		if ($this->gsConfig->onlyInternalFederation()) {
-			return false;
-		}
-		$result = $this->config->getAppValue('files_sharing', 'outgoing_server2server_group_share_enabled', 'no');
-		return ($result === 'yes');
-	}
-
-	/**
-	 * check if users are allowed to receive federated group shares
-	 *
-	 * @return bool
-	 */
-	public function isIncomingServer2serverGroupShareEnabled() {
-		if ($this->gsConfig->onlyInternalFederation()) {
-			return false;
-		}
-		$result = $this->config->getAppValue('files_sharing', 'incoming_server2server_group_share_enabled', 'no');
-		return ($result === 'yes');
-	}
-
-	/**
-	 * check if federated group sharing is supported, therefore the OCM API need to be enabled
-	 *
-	 * @return bool
-	 */
-	public function isFederatedGroupSharingSupported() {
-		return $this->cloudFederationProviderManager->isReady();
-	}
-
-	/**
-	 * Check if querying sharees on the lookup server is enabled
-	 *
-	 * @return bool
-	 */
-	public function isLookupServerQueriesEnabled() {
-		// in a global scale setup we should always query the lookup server
-		if ($this->gsConfig->isGlobalScaleEnabled()) {
-			return true;
-		}
-		$result = $this->config->getAppValue('files_sharing', 'lookupServerEnabled', 'yes');
-		return ($result === 'yes');
-	}
-
-
-	/**
-	 * Check if it is allowed to publish user specific data to the lookup server
-	 *
-	 * @return bool
-	 */
-	public function isLookupServerUploadEnabled() {
-		// in a global scale setup the admin is responsible to keep the lookup server up-to-date
-		if ($this->gsConfig->isGlobalScaleEnabled()) {
-			return false;
-		}
-		$result = $this->config->getAppValue('files_sharing', 'lookupServerUploadEnabled', 'yes');
-		return ($result === 'yes');
-	}
-
-	/**
-	 * @inheritdoc
-	 */
-	public function getAccessList($nodes, $currentAccess) {
-		$ids = [];
-		foreach ($nodes as $node) {
-			$ids[] = $node->getId();
-		}
-
-		$qb = $this->dbConnection->getQueryBuilder();
-		$qb->select('share_with', 'token', 'file_source')
-			->from('share')
-			->where($qb->expr()->eq('share_type', $qb->createNamedParameter(IShare::TYPE_REMOTE)))
-			->andWhere($qb->expr()->in('file_source', $qb->createNamedParameter($ids, IQueryBuilder::PARAM_INT_ARRAY)))
-			->andWhere($qb->expr()->orX(
-				$qb->expr()->eq('item_type', $qb->createNamedParameter('file')),
-				$qb->expr()->eq('item_type', $qb->createNamedParameter('folder'))
-			));
-		$cursor = $qb->execute();
-
-		if ($currentAccess === false) {
-			$remote = $cursor->fetch() !== false;
-			$cursor->closeCursor();
-
-			return ['remote' => $remote];
-		}
-
-		$remote = [];
-		while ($row = $cursor->fetch()) {
-			$remote[$row['share_with']] = [
-				'node_id' => $row['file_source'],
-				'token' => $row['token'],
-			];
-		}
-		$cursor->closeCursor();
-
-		return ['remote' => $remote];
-	}
-
-	public function getAllShares(): iterable {
-		$qb = $this->dbConnection->getQueryBuilder();
-
-		$qb->select('*')
-			->from('share')
-			->where(
-				$qb->expr()->orX(
-					$qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share\IShare::TYPE_REMOTE)),
-					$qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share\IShare::TYPE_REMOTE_GROUP))
-				)
-			);
-
-		$cursor = $qb->execute();
-		while ($data = $cursor->fetch()) {
-			try {
-				$share = $this->createShareObject($data);
-			} catch (InvalidShare $e) {
-				continue;
-			} catch (ShareNotFound $e) {
-				continue;
-			}
-
-			yield $share;
-		}
-		$cursor->closeCursor();
-	}
+        return $share;
+    }
+
+    /**
+     * Get all children of this share
+     *
+     * @param IShare $parent
+     * @return IShare[]
+     */
+    public function getChildren(IShare $parent) {
+        $children = [];
+
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('*')
+            ->from('share')
+            ->where($qb->expr()->eq('parent', $qb->createNamedParameter($parent->getId())))
+            ->andWhere($qb->expr()->in('share_type', $qb->createNamedParameter($this->supportedShareType, IQueryBuilder::PARAM_INT_ARRAY)))
+            ->orderBy('id');
+
+        $cursor = $qb->execute();
+        while ($data = $cursor->fetch()) {
+            $children[] = $this->createShareObject($data);
+        }
+        $cursor->closeCursor();
+
+        return $children;
+    }
+
+    /**
+     * Delete a share (owner unShares the file)
+     *
+     * @param IShare $share
+     * @throws ShareNotFound
+     * @throws \OC\HintException
+     */
+    public function delete(IShare $share) {
+        list(, $remote) = $this->addressHandler->splitUserRemote($share->getSharedWith());
+
+        // if the local user is the owner we can send the unShare request directly...
+        if ($this->userManager->userExists($share->getShareOwner())) {
+            $this->notifications->sendRemoteUnShare($remote, $share->getId(), $share->getToken());
+            $this->revokeShare($share, true);
+        } else { // ... if not we need to correct ID for the unShare request
+            $remoteId = $this->getRemoteId($share);
+            $this->notifications->sendRemoteUnShare($remote, $remoteId, $share->getToken());
+            $this->revokeShare($share, false);
+        }
+
+        // only remove the share when all messages are send to not lose information
+        // about the share to early
+        $this->removeShareFromTable($share);
+    }
+
+    /**
+     * in case of a re-share we need to send the other use (initiator or owner)
+     * a message that the file was unshared
+     *
+     * @param IShare $share
+     * @param bool $isOwner the user can either be the owner or the user who re-sahred it
+     * @throws ShareNotFound
+     * @throws \OC\HintException
+     */
+    protected function revokeShare($share, $isOwner) {
+        if ($this->userManager->userExists($share->getShareOwner()) && $this->userManager->userExists($share->getSharedBy())) {
+            // If both the owner and the initiator of the share are local users we don't have to notify anybody else
+            return;
+        }
+
+        // also send a unShare request to the initiator, if this is a different user than the owner
+        if ($share->getShareOwner() !== $share->getSharedBy()) {
+            if ($isOwner) {
+                list(, $remote) = $this->addressHandler->splitUserRemote($share->getSharedBy());
+            } else {
+                list(, $remote) = $this->addressHandler->splitUserRemote($share->getShareOwner());
+            }
+            $remoteId = $this->getRemoteId($share);
+            $this->notifications->sendRevokeShare($remote, $remoteId, $share->getToken());
+        }
+    }
+
+    /**
+     * remove share from table
+     *
+     * @param IShare $share
+     */
+    public function removeShareFromTable(IShare $share) {
+        $this->removeShareFromTableById($share->getId());
+    }
+
+    /**
+     * remove share from table
+     *
+     * @param string $shareId
+     */
+    private function removeShareFromTableById($shareId) {
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->delete('share')
+            ->where($qb->expr()->eq('id', $qb->createNamedParameter($shareId)))
+            ->andWhere($qb->expr()->neq('share_type', $qb->createNamedParameter(IShare::TYPE_CIRCLE)));
+        $qb->execute();
+
+        $qb->delete('federated_reshares')
+            ->where($qb->expr()->eq('share_id', $qb->createNamedParameter($shareId)));
+        $qb->execute();
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function deleteFromSelf(IShare $share, $recipient) {
+        // nothing to do here. Technically deleteFromSelf in the context of federated
+        // shares is a umount of an external storage. This is handled here
+        // apps/files_sharing/lib/external/manager.php
+        // TODO move this code over to this app
+    }
+
+    public function restore(IShare $share, string $recipient): IShare {
+        throw new GenericShareException('not implemented');
+    }
+
+
+    public function getSharesInFolder($userId, Folder $node, $reshares) {
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('*')
+            ->from('share', 's')
+            ->andWhere($qb->expr()->orX(
+                $qb->expr()->eq('item_type', $qb->createNamedParameter('file')),
+                $qb->expr()->eq('item_type', $qb->createNamedParameter('folder'))
+            ))
+            ->andWhere(
+                $qb->expr()->eq('share_type', $qb->createNamedParameter(IShare::TYPE_REMOTE))
+            );
+
+        /**
+         * Reshares for this user are shares where they are the owner.
+         */
+        if ($reshares === false) {
+            $qb->andWhere($qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId)));
+        } else {
+            $qb->andWhere(
+                $qb->expr()->orX(
+                    $qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
+                    $qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId))
+                )
+            );
+        }
+
+        $qb->innerJoin('s', 'filecache' ,'f', $qb->expr()->eq('s.file_source', 'f.fileid'));
+        $qb->andWhere($qb->expr()->eq('f.parent', $qb->createNamedParameter($node->getId())));
+
+        $qb->orderBy('id');
+
+        $cursor = $qb->execute();
+        $shares = [];
+        while ($data = $cursor->fetch()) {
+            $shares[$data['fileid']][] = $this->createShareObject($data);
+        }
+        $cursor->closeCursor();
+
+        return $shares;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getSharesBy($userId, $shareType, $node, $reshares, $limit, $offset) {
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('*')
+            ->from('share');
+
+        $qb->andWhere($qb->expr()->eq('share_type', $qb->createNamedParameter($shareType)));
+
+        /**
+         * Reshares for this user are shares where they are the owner.
+         */
+        if ($reshares === false) {
+            //Special case for old shares created via the web UI
+            $or1 = $qb->expr()->andX(
+                $qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
+                $qb->expr()->isNull('uid_initiator')
+            );
+
+            $qb->andWhere(
+                $qb->expr()->orX(
+                    $qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId)),
+                    $or1
+                )
+            );
+        } else {
+            $qb->andWhere(
+                $qb->expr()->orX(
+                    $qb->expr()->eq('uid_owner', $qb->createNamedParameter($userId)),
+                    $qb->expr()->eq('uid_initiator', $qb->createNamedParameter($userId))
+                )
+            );
+        }
+
+        if ($node !== null) {
+            $qb->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($node->getId())));
+        }
+
+        if ($limit !== -1) {
+            $qb->setMaxResults($limit);
+        }
+
+        $qb->setFirstResult($offset);
+        $qb->orderBy('id');
+
+        $cursor = $qb->execute();
+        $shares = [];
+        while ($data = $cursor->fetch()) {
+            $shares[] = $this->createShareObject($data);
+        }
+        $cursor->closeCursor();
+
+        return $shares;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getShareById($id, $recipientId = null) {
+        $qb = $this->dbConnection->getQueryBuilder();
+
+        $qb->select('*')
+            ->from('share')
+            ->where($qb->expr()->eq('id', $qb->createNamedParameter($id)))
+            ->andWhere($qb->expr()->in('share_type', $qb->createNamedParameter($this->supportedShareType, IQueryBuilder::PARAM_INT_ARRAY)));
+
+        $cursor = $qb->execute();
+        $data = $cursor->fetch();
+        $cursor->closeCursor();
+
+        if ($data === false) {
+            throw new ShareNotFound('Can not find share with ID: ' . $id);
+        }
+
+        try {
+            $share = $this->createShareObject($data);
+        } catch (InvalidShare $e) {
+            throw new ShareNotFound();
+        }
+
+        return $share;
+    }
+
+    /**
+     * Get shares for a given path
+     *
+     * @param \OCP\Files\Node $path
+     * @return IShare[]
+     */
+    public function getSharesByPath(Node $path) {
+        $qb = $this->dbConnection->getQueryBuilder();
+
+        // get federated user shares
+        $cursor = $qb->select('*')
+            ->from('share')
+            ->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($path->getId())))
+            ->andWhere($qb->expr()->in('share_type', $qb->createNamedParameter($this->supportedShareType, IQueryBuilder::PARAM_INT_ARRAY)))
+            ->execute();
+
+        $shares = [];
+        while ($data = $cursor->fetch()) {
+            $shares[] = $this->createShareObject($data);
+        }
+        $cursor->closeCursor();
+
+        return $shares;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getSharedWith($userId, $shareType, $node, $limit, $offset) {
+        /** @var IShare[] $shares */
+        $shares = [];
+
+        //Get shares directly with this user
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('*')
+            ->from('share');
+
+        // Order by id
+        $qb->orderBy('id');
+
+        // Set limit and offset
+        if ($limit !== -1) {
+            $qb->setMaxResults($limit);
+        }
+        $qb->setFirstResult($offset);
+
+        $qb->where($qb->expr()->in('share_type', $qb->createNamedParameter($this->supportedShareType, IQueryBuilder::PARAM_INT_ARRAY)));
+        $qb->andWhere($qb->expr()->eq('share_with', $qb->createNamedParameter($userId)));
+
+        // Filter by node if provided
+        if ($node !== null) {
+            $qb->andWhere($qb->expr()->eq('file_source', $qb->createNamedParameter($node->getId())));
+        }
+
+        $cursor = $qb->execute();
+
+        while ($data = $cursor->fetch()) {
+            $shares[] = $this->createShareObject($data);
+        }
+        $cursor->closeCursor();
+
+
+        return $shares;
+    }
+
+    /**
+     * Get a share by token
+     *
+     * @param string $token
+     * @return IShare
+     * @throws ShareNotFound
+     */
+    public function getShareByToken($token) {
+        $qb = $this->dbConnection->getQueryBuilder();
+
+        $cursor = $qb->select('*')
+            ->from('share')
+            ->where($qb->expr()->in('share_type', $qb->createNamedParameter($this->supportedShareType, IQueryBuilder::PARAM_INT_ARRAY)))
+            ->andWhere($qb->expr()->eq('token', $qb->createNamedParameter($token)))
+            ->execute();
+
+        $data = $cursor->fetch();
+
+        if ($data === false) {
+            throw new ShareNotFound('Share not found', $this->l->t('Could not find share'));
+        }
+
+        try {
+            $share = $this->createShareObject($data);
+        } catch (InvalidShare $e) {
+            throw new ShareNotFound('Share not found', $this->l->t('Could not find share'));
+        }
+
+        return $share;
+    }
+
+    /**
+     * get database row of a give share
+     *
+     * @param $id
+     * @return array
+     * @throws ShareNotFound
+     */
+    private function getRawShare($id) {
+
+        // Now fetch the inserted share and create a complete share object
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('*')
+            ->from('share')
+            ->where($qb->expr()->eq('id', $qb->createNamedParameter($id)));
+
+        $cursor = $qb->execute();
+        $data = $cursor->fetch();
+        $cursor->closeCursor();
+
+        if ($data === false) {
+            throw new ShareNotFound;
+        }
+
+        return $data;
+    }
+
+    /**
+     * Create a share object from an database row
+     *
+     * @param array $data
+     * @return IShare
+     * @throws InvalidShare
+     * @throws ShareNotFound
+     */
+    private function createShareObject($data) {
+        $share = new Share($this->rootFolder, $this->userManager);
+        $share->setId((int)$data['id'])
+            ->setShareType((int)$data['share_type'])
+            ->setPermissions((int)$data['permissions'])
+            ->setTarget($data['file_target'])
+            ->setMailSend((bool)$data['mail_send'])
+            ->setToken($data['token']);
+
+        $shareTime = new \DateTime();
+        $shareTime->setTimestamp((int)$data['stime']);
+        $share->setShareTime($shareTime);
+        $share->setSharedWith($data['share_with']);
+
+        if ($data['uid_initiator'] !== null) {
+            $share->setShareOwner($data['uid_owner']);
+            $share->setSharedBy($data['uid_initiator']);
+        } else {
+            //OLD SHARE
+            $share->setSharedBy($data['uid_owner']);
+            $path = $this->getNode($share->getSharedBy(), (int)$data['file_source']);
+
+            $owner = $path->getOwner();
+            $share->setShareOwner($owner->getUID());
+        }
+
+        $share->setNodeId((int)$data['file_source']);
+        $share->setNodeType($data['item_type']);
+
+        $share->setProviderId($this->identifier());
+
+        return $share;
+    }
+
+    /**
+     * Get the node with file $id for $user
+     *
+     * @param string $userId
+     * @param int $id
+     * @return \OCP\Files\File|\OCP\Files\Folder
+     * @throws InvalidShare
+     */
+    private function getNode($userId, $id) {
+        try {
+            $userFolder = $this->rootFolder->getUserFolder($userId);
+        } catch (NotFoundException $e) {
+            throw new InvalidShare();
+        }
+
+        $nodes = $userFolder->getById($id);
+
+        if (empty($nodes)) {
+            throw new InvalidShare();
+        }
+
+        return $nodes[0];
+    }
+
+    /**
+     * A user is deleted from the system
+     * So clean up the relevant shares.
+     *
+     * @param string $uid
+     * @param int $shareType
+     */
+    public function userDeleted($uid, $shareType) {
+        //TODO: probabaly a good idea to send unshare info to remote servers
+
+        $qb = $this->dbConnection->getQueryBuilder();
+
+        $qb->delete('share')
+            ->where($qb->expr()->eq('share_type', $qb->createNamedParameter(IShare::TYPE_REMOTE)))
+            ->andWhere($qb->expr()->eq('uid_owner', $qb->createNamedParameter($uid)))
+            ->execute();
+    }
+
+    /**
+     * This provider does not handle groups
+     *
+     * @param string $gid
+     */
+    public function groupDeleted($gid) {
+        // We don't handle groups here
+    }
+
+    /**
+     * This provider does not handle groups
+     *
+     * @param string $uid
+     * @param string $gid
+     */
+    public function userDeletedFromGroup($uid, $gid) {
+        // We don't handle groups here
+    }
+
+    /**
+     * check if users from other Nextcloud instances are allowed to mount public links share by this instance
+     *
+     * @return bool
+     */
+    public function isOutgoingServer2serverShareEnabled() {
+        if ($this->gsConfig->onlyInternalFederation()) {
+            return false;
+        }
+        $result = $this->config->getAppValue('files_sharing', 'outgoing_server2server_share_enabled', 'yes');
+        return ($result === 'yes');
+    }
+
+    /**
+     * check if users are allowed to mount public links from other Nextclouds
+     *
+     * @return bool
+     */
+    public function isIncomingServer2serverShareEnabled() {
+        if ($this->gsConfig->onlyInternalFederation()) {
+            return false;
+        }
+        $result = $this->config->getAppValue('files_sharing', 'incoming_server2server_share_enabled', 'yes');
+        return ($result === 'yes');
+    }
+
+
+    /**
+     * check if users from other Nextcloud instances are allowed to send federated group shares
+     *
+     * @return bool
+     */
+    public function isOutgoingServer2serverGroupShareEnabled() {
+        if ($this->gsConfig->onlyInternalFederation()) {
+            return false;
+        }
+        $result = $this->config->getAppValue('files_sharing', 'outgoing_server2server_group_share_enabled', 'no');
+        return ($result === 'yes');
+    }
+
+    /**
+     * check if users are allowed to receive federated group shares
+     *
+     * @return bool
+     */
+    public function isIncomingServer2serverGroupShareEnabled() {
+        if ($this->gsConfig->onlyInternalFederation()) {
+            return false;
+        }
+        $result = $this->config->getAppValue('files_sharing', 'incoming_server2server_group_share_enabled', 'no');
+        return ($result === 'yes');
+    }
+
+    /**
+     * check if federated group sharing is supported, therefore the OCM API need to be enabled
+     *
+     * @return bool
+     */
+    public function isFederatedGroupSharingSupported() {
+        return $this->cloudFederationProviderManager->isReady();
+    }
+
+    /**
+     * Check if querying sharees on the lookup server is enabled
+     *
+     * @return bool
+     */
+    public function isLookupServerQueriesEnabled() {
+        // in a global scale setup we should always query the lookup server
+        if ($this->gsConfig->isGlobalScaleEnabled()) {
+            return true;
+        }
+        $result = $this->config->getAppValue('files_sharing', 'lookupServerEnabled', 'yes');
+        return ($result === 'yes');
+    }
+
+
+    /**
+     * Check if it is allowed to publish user specific data to the lookup server
+     *
+     * @return bool
+     */
+    public function isLookupServerUploadEnabled() {
+        // in a global scale setup the admin is responsible to keep the lookup server up-to-date
+        if ($this->gsConfig->isGlobalScaleEnabled()) {
+            return false;
+        }
+        $result = $this->config->getAppValue('files_sharing', 'lookupServerUploadEnabled', 'yes');
+        return ($result === 'yes');
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getAccessList($nodes, $currentAccess) {
+        $ids = [];
+        foreach ($nodes as $node) {
+            $ids[] = $node->getId();
+        }
+
+        $qb = $this->dbConnection->getQueryBuilder();
+        $qb->select('share_with', 'token', 'file_source')
+            ->from('share')
+            ->where($qb->expr()->eq('share_type', $qb->createNamedParameter(IShare::TYPE_REMOTE)))
+            ->andWhere($qb->expr()->in('file_source', $qb->createNamedParameter($ids, IQueryBuilder::PARAM_INT_ARRAY)))
+            ->andWhere($qb->expr()->orX(
+                $qb->expr()->eq('item_type', $qb->createNamedParameter('file')),
+                $qb->expr()->eq('item_type', $qb->createNamedParameter('folder'))
+            ));
+        $cursor = $qb->execute();
+
+        if ($currentAccess === false) {
+            $remote = $cursor->fetch() !== false;
+            $cursor->closeCursor();
+
+            return ['remote' => $remote];
+        }
+
+        $remote = [];
+        while ($row = $cursor->fetch()) {
+            $remote[$row['share_with']] = [
+                'node_id' => $row['file_source'],
+                'token' => $row['token'],
+            ];
+        }
+        $cursor->closeCursor();
+
+        return ['remote' => $remote];
+    }
+
+    public function getAllShares(): iterable {
+        $qb = $this->dbConnection->getQueryBuilder();
+
+        $qb->select('*')
+            ->from('share')
+            ->where(
+                $qb->expr()->orX(
+                    $qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share\IShare::TYPE_REMOTE)),
+                    $qb->expr()->eq('share_type', $qb->createNamedParameter(\OCP\Share\IShare::TYPE_REMOTE_GROUP))
+                )
+            );
+
+        $cursor = $qb->execute();
+        while ($data = $cursor->fetch()) {
+            try {
+                $share = $this->createShareObject($data);
+            } catch (InvalidShare $e) {
+                continue;
+            } catch (ShareNotFound $e) {
+                continue;
+            }
+
+            yield $share;
+        }
+        $cursor->closeCursor();
+    }
 }