Merge pull request #919 from nextcloud/misc/noid/notification-and-migration

Notification and Migration

19 files changed, 450 insertions, 28 deletions

diff --git a/appinfo/app.php b/appinfo/app.php
index e61bbf60..5a8c2071 100644
--- a/appinfo/app.php
+++ b/appinfo/app.php
@@ -33,3 +33,9 @@ namespace OCA\Social\AppInfo;
 require_once __DIR__ . '/autoload.php';
 
 
+/** @var Application $app */
+$app = \OC::$server->query(Application::class);
+
+$app->checkUpgradeStatus();
+
+
diff --git a/appinfo/info.xml b/appinfo/info.xml
index 2568bb2b..44156d58 100644
--- a/appinfo/info.xml
+++ b/appinfo/info.xml
@@ -32,7 +32,7 @@
 	<repository type="git">https://github.com/nextcloud/social.git</repository>
 	<screenshot>https://raw.githubusercontent.com/nextcloud/social/master/img/screenshot.png</screenshot>
 	<dependencies>
-		<nextcloud min-version="15" max-version="19"/>
+		<nextcloud min-version="17" max-version="19"/>
 		<database>pgsql</database>
 		<database>sqlite</database>
 		<database>mysql</database>
diff --git a/img/social_dark.svg b/img/social_dark.svg
new file mode 100644
index 00000000..8bfbf968
--- /dev/null
+++ b/img/social_dark.svg
@@ -0,0 +1,55 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   xmlns:dc="http://purl.org/dc/elements/1.1/"
+   xmlns:cc="http://creativecommons.org/ns#"
+   xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+   xmlns:svg="http://www.w3.org/2000/svg"
+   xmlns="http://www.w3.org/2000/svg"
+   xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+   xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+   version="1.1"
+   width="32"
+   height="32"
+   viewBox="0 0 32 32"
+   id="svg4"
+   sodipodi:docname="social.svg"
+   inkscape:version="0.92.3 (2405546, 2018-03-11)">
+  <metadata
+     id="metadata10">
+    <rdf:RDF>
+      <cc:Work
+         rdf:about="">
+        <dc:format>image/svg+xml</dc:format>
+        <dc:type
+           rdf:resource="http://purl.org/dc/dcmitype/StillImage" />
+      </cc:Work>
+    </rdf:RDF>
+  </metadata>
+  <defs
+     id="defs8" />
+  <sodipodi:namedview
+     pagecolor="#ffffff"
+     bordercolor="#666666"
+     borderopacity="1"
+     objecttolerance="10"
+     gridtolerance="10"
+     guidetolerance="10"
+     inkscape:pageopacity="0"
+     inkscape:pageshadow="2"
+     inkscape:window-width="1920"
+     inkscape:window-height="1046"
+     id="namedview6"
+     showgrid="false"
+     inkscape:zoom="7.375"
+     inkscape:cx="-35.79661"
+     inkscape:cy="16"
+     inkscape:window-x="0"
+     inkscape:window-y="34"
+     inkscape:window-maximized="1"
+     inkscape:current-layer="svg4" />
+  <path
+     d="M 16,29 13.97,27.152 C 6.76,20.614 2,16.288 2,11.01 2,6.684 5.388,3.31 9.7,3.31 c 2.436,0 4.774,1.134 6.3,2.912 1.526,-1.778 3.864,-2.912 6.3,-2.912 4.312,0 7.7,3.374 7.7,7.7 0,5.278 -4.76,9.604 -11.97,16.142 z"
+     id="path2"
+     inkscape:connector-curvature="0"
+     style="fill:#000000;stroke-width:1.39999998" />
+</svg>
diff --git a/lib/AppInfo/Application.php b/lib/AppInfo/Application.php
index d20ff7f1..18996bac 100644
--- a/lib/AppInfo/Application.php
+++ b/lib/AppInfo/Application.php
@@ -31,15 +31,36 @@ declare(strict_types=1);
 namespace OCA\Social\AppInfo;
 
 
+use OC\DB\SchemaWrapper;
+use OCA\Social\Notification\Notifier;
+use OCA\Social\Service\ConfigService;
+use OCA\Social\Service\UpdateService;
 use OCP\AppFramework\App;
+use OCP\AppFramework\IAppContainer;
+use OCP\AppFramework\QueryException;
 
 
+/**
+ * Class Application
+ *
+ * @package OCA\Social\AppInfo
+ */
 class Application extends App {
 
 
 	const APP_NAME = 'social';
 
 
+	/** @var ConfigService */
+	private $configService;
+
+	/** @var UpdateService */
+	private $updateService;
+
+	/** @var IAppContainer */
+	private $container;
+
+
 	/**
 	 * Application constructor.
 	 *
@@ -47,6 +68,41 @@ class Application extends App {
 	 */
 	public function __construct(array $params = []) {
 		parent::__construct(self::APP_NAME, $params);
+
+		$this->container = $this->getContainer();
+
+		$manager = $this->container->getServer()
+								   ->getNotificationManager();
+		$manager->registerNotifierService(Notifier::class);
+	}
+
+
+	/**
+	 *
+	 */
+	public function checkUpgradeStatus() {
+		$upgradeChecked = $this->container->getServer()
+										  ->getConfig()
+										  ->getAppValue(Application::APP_NAME, 'update_checked', '');
+
+		if ($upgradeChecked === '0.3') {
+			return;
+		}
+
+		try {
+			$this->configService = $this->container->query(ConfigService::class);
+			$this->updateService = $this->container->query(UpdateService::class);
+		} catch (QueryException $e) {
+			return;
+		}
+
+		$server = $this->container->getServer();
+		$schema = new SchemaWrapper($server->getDatabaseConnection());
+		if ($schema->hasTable('social_a2_stream')) {
+			$this->updateService->checkUpdateStatus();
+		}
+
+		$this->configService->setAppValue('update_checked', '0.3');
 	}
 
 }
diff --git a/lib/Db/ActionsRequestBuilder.php b/lib/Db/ActionsRequestBuilder.php
index fa760304..3178b8d8 100644
--- a/lib/Db/ActionsRequestBuilder.php
+++ b/lib/Db/ActionsRequestBuilder.php
@@ -88,6 +88,7 @@ class ActionsRequestBuilder extends CoreRequestBuilder {
 		   ->from(self::TABLE_ACTIONS, 'a');
 
 		$this->defaultSelectAlias = 'a';
+		$qb->setDefaultSelectAlias('a');
 
 		return $qb;
 	}
@@ -104,6 +105,7 @@ class ActionsRequestBuilder extends CoreRequestBuilder {
 		   ->from(self::TABLE_ACTIONS, 'a');
 
 		$this->defaultSelectAlias = 'a';
+		$qb->setDefaultSelectAlias('a');
 
 		return $qb;
 	}
diff --git a/lib/Db/ActorsRequestBuilder.php b/lib/Db/ActorsRequestBuilder.php
index a1fb23ec..c8bcd6cc 100644
--- a/lib/Db/ActorsRequestBuilder.php
+++ b/lib/Db/ActorsRequestBuilder.php
@@ -70,10 +70,10 @@ class ActorsRequestBuilder extends CoreRequestBuilder {
 	/**
 	 * Base of the Sql Select request for Shares
 	 *
-	 * @return IQueryBuilder
+	 * @return SocialQueryBuilder
 	 */
-	protected function getActorsSelectSql(): IQueryBuilder {
-		$qb = $this->dbConnection->getQueryBuilder();
+	protected function getActorsSelectSql(): SocialQueryBuilder {
+		$qb = $this->getQueryBuilder();
 
 		/** @noinspection PhpMethodParametersCountMismatchInspection */
 		$qb->select(
@@ -83,6 +83,7 @@ class ActorsRequestBuilder extends CoreRequestBuilder {
 		   ->from(self::TABLE_ACTORS, 'a');
 
 		$this->defaultSelectAlias = 'a';
+		$qb->setDefaultSelectAlias('a');
 
 		return $qb;
 	}
diff --git a/lib/Db/CacheActorsRequestBuilder.php b/lib/Db/CacheActorsRequestBuilder.php
index 3d595838..0289e204 100644
--- a/lib/Db/CacheActorsRequestBuilder.php
+++ b/lib/Db/CacheActorsRequestBuilder.php
@@ -90,7 +90,8 @@ class CacheActorsRequestBuilder extends CoreRequestBuilder {
 
 		/** @deprecated */
 		$this->defaultSelectAlias = 'ca';
-
+		$qb->setDefaultSelectAlias('ca');
+		
 		return $qb;
 	}
 
diff --git a/lib/Db/CacheDocumentsRequestBuilder.php b/lib/Db/CacheDocumentsRequestBuilder.php
index c21869b9..59171dec 100644
--- a/lib/Db/CacheDocumentsRequestBuilder.php
+++ b/lib/Db/CacheDocumentsRequestBuilder.php
@@ -69,10 +69,10 @@ class CacheDocumentsRequestBuilder extends CoreRequestBuilder {
 	/**
 	 * Base of the Sql Select request for Shares
 	 *
-	 * @return IQueryBuilder
+	 * @return SocialQueryBuilder
 	 */
-	protected function getCacheDocumentsSelectSql(): IQueryBuilder {
-		$qb = $this->dbConnection->getQueryBuilder();
+	protected function getCacheDocumentsSelectSql(): SocialQueryBuilder {
+		$qb = $this->getQueryBuilder();
 
 		/** @noinspection PhpMethodParametersCountMismatchInspection */
 		$qb->select(
@@ -82,6 +82,7 @@ class CacheDocumentsRequestBuilder extends CoreRequestBuilder {
 		   ->from(self::TABLE_CACHE_DOCUMENTS, 'cd');
 
 		$this->defaultSelectAlias = 'cd';
+		$qb->setDefaultSelectAlias('cd');
 
 		return $qb;
 	}
diff --git a/lib/Db/FollowsRequest.php b/lib/Db/FollowsRequest.php
index c9138ba4..d466aa4f 100644
--- a/lib/Db/FollowsRequest.php
+++ b/lib/Db/FollowsRequest.php
@@ -167,7 +167,7 @@ class FollowsRequest extends FollowsRequestBuilder {
 	 */
 	public function countFollowers(string $actorId): int {
 		$qb = $this->countFollowsSelectSql();
-		$qb->limitToObjectId($actorId);
+		$qb->limitToObjectIdPrim($qb->prim($actorId));
 		$qb->limitToType(Follow::TYPE);
 		$qb->limitToAccepted(true);
 
@@ -186,7 +186,7 @@ class FollowsRequest extends FollowsRequestBuilder {
 	 */
 	public function countFollowing(string $actorId): int {
 		$qb = $this->countFollowsSelectSql();
-		$qb->limitToActorId($actorId);
+		$qb->limitToActorIdPrim($qb->prim($actorId));
 		$qb->limitToType(Follow::TYPE);
 		$qb->limitToAccepted(true);
 
diff --git a/lib/Db/FollowsRequestBuilder.php b/lib/Db/FollowsRequestBuilder.php
index eb3bc2d4..ff11642f 100644
--- a/lib/Db/FollowsRequestBuilder.php
+++ b/lib/Db/FollowsRequestBuilder.php
@@ -77,10 +77,10 @@ class FollowsRequestBuilder extends CoreRequestBuilder {
 	/**
 	 * Base of the Sql Select request for Shares
 	 *
-	 * @return IQueryBuilder
+	 * @return SocialQueryBuilder
 	 */
-	protected function getFollowsSelectSql(): IQueryBuilder {
-		$qb = $this->dbConnection->getQueryBuilder();
+	protected function getFollowsSelectSql(): SocialQueryBuilder {
+		$qb = $this->getQueryBuilder();
 
 		/** @noinspection PhpMethodParametersCountMismatchInspection */
 		$qb->select(
@@ -89,6 +89,7 @@ class FollowsRequestBuilder extends CoreRequestBuilder {
 		   ->from(self::TABLE_FOLLOWS, 'f');
 
 		$this->defaultSelectAlias = 'f';
+		$qb->setDefaultSelectAlias('f');
 
 		return $qb;
 	}
@@ -104,6 +105,7 @@ class FollowsRequestBuilder extends CoreRequestBuilder {
 		$qb->selectAlias($qb->createFunction('COUNT(*)'), 'count')
 		   ->from(self::TABLE_FOLLOWS, 'f');
 
+		$qb->setDefaultSelectAlias('f');
 		$this->defaultSelectAlias = 'f';
 
 		return $qb;
diff --git a/lib/Db/HashtagsRequestBuilder.php b/lib/Db/HashtagsRequestBuilder.php
index 6ed4e92b..f3ab9d0c 100644
--- a/lib/Db/HashtagsRequestBuilder.php
+++ b/lib/Db/HashtagsRequestBuilder.php
@@ -75,16 +75,17 @@ class HashtagsRequestBuilder extends CoreRequestBuilder {
 	/**
 	 * Base of the Sql Select request for Shares
 	 *
-	 * @return IQueryBuilder
+	 * @return SocialQueryBuilder
 	 */
-	protected function getHashtagsSelectSql(): IQueryBuilder {
-		$qb = $this->dbConnection->getQueryBuilder();
+	protected function getHashtagsSelectSql(): SocialQueryBuilder {
+		$qb = $this->getQueryBuilder();
 
 		/** @noinspection PhpMethodParametersCountMismatchInspection */
 		$qb->select('h.hashtag', 'h.trend')
 		   ->from(self::TABLE_HASHTAGS, 'h');
 
 		$this->defaultSelectAlias = 'h';
+		$qb->setDefaultSelectAlias('h');
 
 		return $qb;
 	}
diff --git a/lib/Db/RequestQueueRequestBuilder.php b/lib/Db/RequestQueueRequestBuilder.php
index 4d0f5f63..eb2de66d 100644
--- a/lib/Db/RequestQueueRequestBuilder.php
+++ b/lib/Db/RequestQueueRequestBuilder.php
@@ -72,7 +72,7 @@ class RequestQueueRequestBuilder extends CoreRequestBuilder {
 	 * @return IQueryBuilder
 	 */
 	protected function getRequestQueueSelectSql(): IQueryBuilder {
-		$qb = $this->dbConnection->getQueryBuilder();
+		$qb = $this->getQueryBuilder();
 
 		/** @noinspection PhpMethodParametersCountMismatchInspection */
 		$qb->select(
@@ -82,6 +82,7 @@ class RequestQueueRequestBuilder extends CoreRequestBuilder {
 		   ->from(self::TABLE_REQUEST_QUEUE, 'rq');
 
 		$this->defaultSelectAlias = 'rq';
+		$qb->setDefaultSelectAlias('rq');
 
 		return $qb;
 	}
diff --git a/lib/Db/StreamActionsRequestBuilder.php b/lib/Db/StreamActionsRequestBuilder.php
index fc68aff5..5297cc12 100644
--- a/lib/Db/StreamActionsRequestBuilder.php
+++ b/lib/Db/StreamActionsRequestBuilder.php
@@ -75,16 +75,17 @@ class StreamActionsRequestBuilder extends CoreRequestBuilder {
 	/**
 	 * Base of the Sql Select request for Shares
 	 *
-	 * @return IQueryBuilder
+	 * @return SocialQueryBuilder
 	 */
-	protected function getStreamActionSelectSql(): IQueryBuilder {
-		$qb = $this->dbConnection->getQueryBuilder();
+	protected function getStreamActionSelectSql(): SocialQueryBuilder {
+		$qb = $this->getQueryBuilder();
 
 		/** @noinspection PhpMethodParametersCountMismatchInspection */
 		$qb->select('sa.id', 'sa.actor_id', 'sa.stream_id', 'sa.values')
 		   ->from(self::TABLE_STREAM_ACTIONS, 'sa');
 
 		$this->defaultSelectAlias = 'sa';
+		$qb->setDefaultSelectAlias('sa');
 
 		return $qb;
 	}
diff --git a/lib/Db/StreamDestRequestBuilder.php b/lib/Db/StreamDestRequestBuilder.php
index 986e0215..38c89863 100644
--- a/lib/Db/StreamDestRequestBuilder.php
+++ b/lib/Db/StreamDestRequestBuilder.php
@@ -74,9 +74,9 @@ class StreamDestRequestBuilder extends CoreRequestBuilder {
 	/**
 	 * Base of the Sql Select request for Shares
 	 *
-	 * @return IQueryBuilder
+	 * @return SocialQueryBuilder
 	 */
-	protected function getStreamDestSelectSql(): IQueryBuilder {
+	protected function getStreamDestSelectSql(): SocialQueryBuilder {
 		$qb = $this->getQueryBuilder();
 
 		/** @noinspection PhpMethodParametersCountMismatchInspection */
@@ -84,6 +84,7 @@ class StreamDestRequestBuilder extends CoreRequestBuilder {
 		   ->from(self::TABLE_STREAM_DEST, 'sd');
 
 		$this->defaultSelectAlias = 'sd';
+		$qb->setDefaultSelectAlias('sd');
 
 		return $qb;
 	}
@@ -105,14 +106,15 @@ class StreamDestRequestBuilder extends CoreRequestBuilder {
 	/**
 	 * Base of the Sql Select request for Shares
 	 *
-	 * @return IQueryBuilder
+	 * @return SocialQueryBuilder
 	 */
-	protected function countStreamDestSelectSql(): IQueryBuilder {
+	protected function countStreamDestSelectSql(): SocialQueryBuilder {
 		$qb = $this->getQueryBuilder();
 		$qb->selectAlias($qb->createFunction('COUNT(*)'), 'count')
 		   ->from(self::TABLE_STREAM_DEST, 'sd');
 
 		$this->defaultSelectAlias = 'sd';
+		$qb->setDefaultSelectAlias('sd');
 
 		return $qb;
 	}
diff --git a/lib/Db/StreamQueueRequest.php b/lib/Db/StreamQueueRequest.php
index 70b1eb9d..871b8f99 100644
--- a/lib/Db/StreamQueueRequest.php
+++ b/lib/Db/StreamQueueRequest.php
@@ -91,7 +91,7 @@ class StreamQueueRequest extends StreamQueueRequestBuilder {
 	 */
 	public function getFromToken(string $token): array {
 		$qb = $this->getStreamQueueSelectSql();
-		$this->limitToToken($qb, $token);
+		$qb->limitToToken($token);
 
 		$queue = [];
 		$cursor = $qb->execute();
diff --git a/lib/Db/StreamQueueRequestBuilder.php b/lib/Db/StreamQueueRequestBuilder.php
index 39509ce0..1e108920 100644
--- a/lib/Db/StreamQueueRequestBuilder.php
+++ b/lib/Db/StreamQueueRequestBuilder.php
@@ -69,10 +69,10 @@ class StreamQueueRequestBuilder extends CoreRequestBuilder {
 	/**
 	 * Base of the Sql Select request for Shares
 	 *
-	 * @return IQueryBuilder
+	 * @return SocialQueryBuilder
 	 */
-	protected function getStreamQueueSelectSql(): IQueryBuilder {
-		$qb = $this->dbConnection->getQueryBuilder();
+	protected function getStreamQueueSelectSql(): SocialQueryBuilder {
+		$qb = $this->getQueryBuilder();
 
 		/** @noinspection PhpMethodParametersCountMismatchInspection */
 		$qb->select(
@@ -81,6 +81,7 @@ class StreamQueueRequestBuilder extends CoreRequestBuilder {
 		   ->from(self::TABLE_STREAM_QUEUE, 'qs');
 
 		$this->defaultSelectAlias = 'qs';
+		$qb->setDefaultSelectAlias('qs');
 
 		return $qb;
 	}
diff --git a/lib/Db/StreamTagsRequestBuilder.php b/lib/Db/StreamTagsRequestBuilder.php
index 25fe9f67..0290253a 100644
--- a/lib/Db/StreamTagsRequestBuilder.php
+++ b/lib/Db/StreamTagsRequestBuilder.php
@@ -84,6 +84,7 @@ class StreamTagsRequestBuilder extends CoreRequestBuilder {
 		   ->from(self::TABLE_STREAM_TAGS, 'st');
 
 		$this->defaultSelectAlias = 'st';
+		$qb->setDefaultSelectAlias('st');
 
 		return $qb;
 	}
diff --git a/lib/Notification/Notifier.php b/lib/Notification/Notifier.php
new file mode 100644
index 00000000..1b7db739
--- /dev/null
+++ b/lib/Notification/Notifier.php
@@ -0,0 +1,150 @@
+<?php declare(strict_types=1);
+
+
+/**
+ * Nextcloud - Social Support
+ *
+ * This file is licensed under the Affero General Public License version 3 or
+ * later. See the COPYING file.
+ *
+ * @author Maxence Lange <maxence@artificial-owl.com>
+ * @copyright 2018, Maxence Lange <maxence@artificial-owl.com>
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+
+namespace OCA\Social\Notification;
+
+
+use InvalidArgumentException;
+use OC;
+use OCA\Social\AppInfo\Application;
+use OCP\Contacts\IManager;
+use OCP\Federation\ICloudIdManager;
+use OCP\IL10N;
+use OCP\IURLGenerator;
+use OCP\L10N\IFactory;
+use OCP\Notification\INotification;
+use OCP\Notification\INotifier;
+
+
+/**
+ * Class Notifier
+ *
+ * @package OCA\Social\Notification
+ */
+class Notifier implements INotifier {
+
+
+	/** @var IL10N */
+	private $l10n;
+
+	/** @var IFactory */
+	protected $factory;
+
+	/** @var IManager */
+	protected $contactsManager;
+
+	/** @var IURLGenerator */
+	protected $url;
+
+	/** @var ICloudIdManager */
+	protected $cloudIdManager;
+
+
+	public function __construct(
+		IL10N $l10n, IFactory $factory, IManager $contactsManager, IURLGenerator $url,
+		ICloudIdManager $cloudIdManager
+	) {
+		$this->l10n = $l10n;
+		$this->factory = $factory;
+		$this->contactsManager = $contactsManager;
+		$this->url = $url;
+		$this->cloudIdManager = $cloudIdManager;
+	}
+
+	/**
+	 * Identifier of the notifier, only use [a-z0-9_]
+	 *
+	 * @return string
+	 * @since 17.0.0
+	 */
+	public function getID(): string {
+		return Application::APP_NAME;
+	}
+
+	/**
+	 * Human readable name describing the notifier
+	 *
+	 * @return string
+	 * @since 17.0.0
+	 */
+	public function getName(): string {
+		return $this->l10n->t('Social');
+	}
+
+	/**
+	 * @param INotification $notification
+	 * @param string $languageCode The code of the language that should be used to prepare the notification
+	 *
+	 * @return INotification
+	 * @throws InvalidArgumentException
+	 */
+	public function prepare(INotification $notification, string $languageCode): INotification {
+		if ($notification->getApp() !== Application::APP_NAME) {
+			throw new InvalidArgumentException();
+		}
+
+		$l10n = OC::$server->getL10N(Application::APP_NAME, $languageCode);
+
+		$notification->setIcon(
+			$this->url->getAbsoluteURL($this->url->imagePath('social', 'social_dark.svg'))
+		);
+		$params = $notification->getSubjectParameters();
+
+		switch ($notification->getSubject()) {
+			case 'update_alpha3':
+				$notification->setParsedSubject('The Social App have been updated to alpha3.');
+				$notification->setParsedMessage(
+					$l10n->t(
+						'Please note that the data from alpha2 can only be migrated manually.
+						A detailed documentation to guide you during this process is available using the button below.',
+						$params
+					)
+				);
+				break;
+
+			default:
+				throw new InvalidArgumentException();
+		}
+
+
+		foreach ($notification->getActions() as $action) {
+			switch ($action->getLabel()) {
+				case 'help':
+					$action->setParsedLabel((string)$l10n->t('Help'))
+						   ->setPrimary(true);
+					break;
+			}
+
+			$notification->addParsedAction($action);
+		}
+
+		return $notification;
+	}
+
+}
diff --git a/lib/Service/UpdateService.php b/lib/Service/UpdateService.php
new file mode 100644
index 00000000..6a36bd19
--- /dev/null
+++ b/lib/Service/UpdateService.php
@@ -0,0 +1,141 @@
+<?php
+/**
+ * @copyright Copyright (c) 2018 Julius Härtl <jus@bitgrid.net>
+ *
+ * @author Julius Härtl <jus@bitgrid.net>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Social\Service;
+
+
+use OCP\AppFramework\Utility\ITimeFactory;
+use OCP\IGroupManager;
+use OCP\IUserManager;
+use OCP\Notification\IManager as INotificationManager;
+use OCP\Notification\INotification;
+
+
+/**
+ * Class UpdateService
+ *
+ * @package OCA\Social\Service
+ */
+class UpdateService {
+
+
+	/** @var IUserManager */
+	private $userManager;
+
+	/** @var IGroupManager */
+	private $groupManager;
+
+	/** @var ITimeFactory */
+	private $time;
+
+	/** @var INotificationManager */
+	private $notificationManager;
+
+
+	/** @var string */
+	private $updateId = 'alpha3';
+
+
+	/**
+	 * UpdateService constructor.
+	 *
+	 * @param IUserManager $userManager
+	 * @param IGroupManager $groupManager
+	 * @param ITimeFactory $time
+	 * @param INotificationManager $notificationManager
+	 */
+	public function __construct(
+		IUserManager $userManager, IGroupManager $groupManager, ITimeFactory $time,
+		INotificationManager $notificationManager
+	) {
+		$this->userManager = $userManager;
+		$this->groupManager = $groupManager;
+		$this->time = $time;
+		$this->notificationManager = $notificationManager;
+	}
+
+
+	public function checkUpdateStatus() {
+		$notifications = $this->generateNotifications(true, 'update_alpha3', []);
+
+		foreach ($notifications as $notif) {
+			$help = $notif->createAction();
+			$help->setLabel('help')
+				 ->setLink('https://help.nextcloud.com/t/social-alpha3-how-to-upgrade/85535', 'WEB');
+
+			$notif->addAction($help);
+			$this->notificationManager->notify($notif);
+		}
+	}
+
+
+	/**
+	 * @param bool $adminOnly
+	 * @param string $subject
+	 * @param array $data
+	 *
+	 * @return INotification[]
+	 */
+	public function generateNotifications(bool $adminOnly, string $subject, array $data): array {
+		$notifications = [];
+		$users = $this->userManager->search('');
+
+		if ($adminOnly) {
+			$admin = [];
+			foreach ($users as $user) {
+				if ($this->groupManager->isAdmin($user->getUID())) {
+					$admin[] = $user;
+				}
+			}
+			$users = $admin;
+		}
+
+		foreach ($users as $user) {
+			$notifications[] = $this->createNotification($user->getUID(), $subject, $data);
+		}
+
+		return $notifications;
+	}
+
+
+	/**
+	 * @param string $userId
+	 * @param string $subject
+	 * @param array $data
+	 *
+	 * @return INotification
+	 */
+	public function createNotification(string $userId, string $subject, array $data): INotification {
+		$now = $this->time->getDateTime();
+		$notification = $this->notificationManager->createNotification();
+		$notification->setApp('social')
+					 ->setDateTime($now)
+					 ->setUser($userId)
+					 ->setObject('update', 'update_' . $this->updateId)
+					 ->setSubject($subject, $data);
+
+		return $notification;
+	}
+
+}
+