Add group display name cache

Signed-off-by: Anna Larch <anna@nextcloud.com>

3 files changed, 104 insertions, 2 deletions

diff --git a/lib/private/Group/DisplayNameCache.php b/lib/private/Group/DisplayNameCache.php
new file mode 100644
index 00000000000..d724b6caf0e
--- /dev/null
+++ b/lib/private/Group/DisplayNameCache.php
@@ -0,0 +1,87 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright 2022 Anna Larch <anna.larch@gmx.net>
+ * @author Anna Larch <anna.larch@gmx.net>
+ *
+ * @license AGPL-3.0-or-later
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program. If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+
+namespace OC\Group;
+
+use OCP\Cache\CappedMemoryCache;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+use OCP\Group\Events\GroupChangedEvent;
+use OCP\ICache;
+use OCP\ICacheFactory;
+use OCP\IGroupManager;
+
+/**
+ * Class that cache the relation Group ID -> Display name
+ *
+ * This saves fetching the group from the backend for "just" the display name
+ */
+class DisplayNameCache implements IEventListener {
+	private CappedMemoryCache $cache;
+	private ICache $memCache;
+	private IGroupManager $groupManager;
+
+	public function __construct(ICacheFactory $cacheFactory, IGroupManager $groupManager) {
+		$this->cache = new CappedMemoryCache();
+		$this->memCache = $cacheFactory->createDistributed('groupDisplayNameMappingCache');
+		$this->groupManager = $groupManager;
+	}
+
+	public function getDisplayName(string $groupId): ?string {
+		if (isset($this->cache[$groupId])) {
+			return $this->cache[$groupId];
+		}
+		$displayName = $this->memCache->get($groupId);
+		if ($displayName) {
+			$this->cache[$groupId] = $displayName;
+			return $displayName;
+		}
+
+		$group = $this->groupManager->get($groupId);
+		if ($group) {
+			$displayName = $group->getDisplayName();
+		} else {
+			$displayName = null;
+		}
+		$this->cache[$groupId] = $displayName;
+		$this->memCache->set($groupId, $displayName, 60 * 10); // 10 minutes
+
+		return $displayName;
+	}
+
+	public function clear(): void {
+		$this->cache = new CappedMemoryCache();
+		$this->memCache->clear();
+	}
+
+	public function handle(Event $event): void {
+		if ($event instanceof GroupChangedEvent && $event->getFeature() === 'displayName') {
+			$groupId = $event->getGroup()->getGID();
+			$newDisplayName = $event->getValue();
+			$this->cache[$groupId] = $newDisplayName;
+			$this->memCache->set($groupId, $newDisplayName, 60 * 10); // 10 minutes
+		}
+	}
+}
diff --git a/lib/private/Group/Group.php b/lib/private/Group/Group.php
index 2ef4d2ee23f..ae70a611e4e 100644
--- a/lib/private/Group/Group.php
+++ b/lib/private/Group/Group.php
@@ -38,6 +38,7 @@ use OCP\Group\Backend\IGetDisplayNameBackend;
 use OCP\Group\Backend\IHideFromCollaborationBackend;
 use OCP\Group\Backend\INamedBackend;
 use OCP\Group\Backend\ISetDisplayNameBackend;
+use OCP\Group\Events\GroupChangedEvent;
 use OCP\GroupInterface;
 use OCP\IGroup;
 use OCP\IUser;
@@ -112,6 +113,7 @@ class Group implements IGroup {
 				if (($backend instanceof ISetDisplayNameBackend)
 					&& $backend->setDisplayName($this->gid, $displayName)) {
 					$this->displayName = $displayName;
+					$this->dispatcher->dispatch(new GroupChangedEvent($this, 'displayName', $displayName, ''));
 					return true;
 				}
 			}
diff --git a/lib/private/Group/Manager.php b/lib/private/Group/Manager.php
index 28f7a400b41..b718afa5168 100644
--- a/lib/private/Group/Manager.php
+++ b/lib/private/Group/Manager.php
@@ -42,6 +42,7 @@ namespace OC\Group;
 use OC\Hooks\PublicEmitter;
 use OCP\EventDispatcher\IEventDispatcher;
 use OCP\GroupInterface;
+use OCP\ICacheFactory;
 use OCP\IGroup;
 use OCP\IGroupManager;
 use OCP\IUser;
@@ -82,12 +83,16 @@ class Manager extends PublicEmitter implements IGroupManager {
 	/** @var \OC\SubAdmin */
 	private $subAdmin = null;
 
+	private DisplayNameCache $displayNameCache;
+
 	public function __construct(\OC\User\Manager $userManager,
 								EventDispatcherInterface $dispatcher,
-								LoggerInterface $logger) {
+								LoggerInterface $logger,
+								ICacheFactory $cacheFactory) {
 		$this->userManager = $userManager;
 		$this->dispatcher = $dispatcher;
 		$this->logger = $logger;
+		$this->displayNameCache = new DisplayNameCache($cacheFactory, $this);
 
 		$cachedGroups = &$this->cachedGroups;
 		$cachedUserGroups = &$this->cachedUserGroups;
@@ -339,6 +344,14 @@ class Manager extends PublicEmitter implements IGroupManager {
 	}
 
 	/**
+	 * @param string $groupId
+	 * @return ?string
+	 */
+	public function getDisplayName(string $groupId): ?string {
+		return $this->displayNameCache->getDisplayName($groupId);
+	}
+
+	/**
 	 * get an array of groupid and displayName for a user
 	 *
 	 * @param IUser $user
@@ -346,7 +359,7 @@ class Manager extends PublicEmitter implements IGroupManager {
 	 */
 	public function getUserGroupNames(IUser $user) {
 		return array_map(function ($group) {
-			return ['displayName' => $group->getDisplayName()];
+			return ['displayName' => $this->displayNameCache->getDisplayName($group->getGID())];
 		}, $this->getUserGroups($user));
 	}