mount custom cache folder using mount providers

lib/private/Files/Filesystem.php

@@ -423,8 +423,6 @@ class Filesystem {
 
 		$home = \OC\Files\Filesystem::getStorage($user);
 
-		self::mountCacheDir($user);
-
 		// Chance to mount for other storages
 		/** @var \OC\Files\Config\MountProviderCollection $mountConfigManager */
 		$mountConfigManager = \OC::$server->getMountProviderCollection();
@@ -460,23 +458,6 @@ class Filesystem {
 		}
 	}
 
-	/**
-	 * Mounts the cache directory
-	 *
-	 * @param string $user user name
-	 */
-	private static function mountCacheDir($user) {
-		$cacheBaseDir = \OC::$server->getConfig()->getSystemValue('cache_path', '');
-		if ($cacheBaseDir !== '') {
-			$cacheDir = rtrim($cacheBaseDir, '/') . '/' . $user;
-			if (!file_exists($cacheDir)) {
-				mkdir($cacheDir, 0770, true);
-			}
-			// mount external cache dir to "/$user/cache" mount point
-			self::mount('\OC\Files\Storage\Local', array('datadir' => $cacheDir), '/' . $user . '/cache');
-		}
-	}
-
 	/**
 	 * get the default filesystem view
 	 *

lib/private/Server.php

@@ -47,6 +47,7 @@ use OC\Diagnostics\NullQueryLogger;
 use OC\Diagnostics\QueryLogger;
 use OC\Files\Config\UserMountCache;
 use OC\Files\Config\UserMountCacheListener;
+use OC\Files\Mount\CacheMountProvider;
 use OC\Files\Node\HookConnector;
 use OC\Files\Node\LazyRoot;
 use OC\Files\Node\Root;
@@ -444,7 +445,14 @@ class Server extends ServerContainer implements IServerContainer {
 		$this->registerService('MountConfigManager', function (Server $c) {
 			$loader = \OC\Files\Filesystem::getLoader();
 			$mountCache = $c->query('UserMountCache');
-			return new \OC\Files\Config\MountProviderCollection($loader, $mountCache);
+			$manager =  new \OC\Files\Config\MountProviderCollection($loader, $mountCache);
+
+			// builtin providers
+
+			$config = $c->getConfig();
+			$manager->registerProvider(new CacheMountProvider($config));
+
+			return $manager;
 		});
 		$this->registerService('IniWrapper', function ($c) {
 			return new IniGetWrapper();

lib/private/files/mount/cachemountprovider.php

@@ -0,0 +1,69 @@
+<?php
+/**
+ * @author Robin Appelman <icewind@owncloud.com>
+ *
+ * @copyright Copyright (c) 2016, ownCloud, Inc.
+ * @license AGPL-3.0
+ *
+ * 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\Files\Mount;
+
+use OCP\Files\Config\IMountProvider;
+use OCP\Files\Storage\IStorageFactory;
+use OCP\IConfig;
+use OCP\IUser;
+
+/**
+ * Mount provider for custom cache storages
+ */
+class CacheMountProvider implements IMountProvider {
+	/**
+	 * @var IConfig
+	 */
+	private $config;
+
+	/**
+	 * ObjectStoreHomeMountProvider constructor.
+	 *
+	 * @param IConfig $config
+	 */
+	public function __construct(IConfig $config) {
+		$this->config = $config;
+	}
+
+	/**
+	 * Get the cache mount for a user
+	 *
+	 * @param IUser $user
+	 * @param IStorageFactory $loader
+	 * @return \OCP\Files\Mount\IMountPoint[]
+	 */
+	public function getMountsForUser(IUser $user, IStorageFactory $loader) {
+		$cacheBaseDir = $this->config->getSystemValue('cache_path', '');
+		if ($cacheBaseDir !== '') {
+			$cacheDir = rtrim($cacheBaseDir, '/') . '/' . $user->getUID();
+			if (!file_exists($cacheDir)) {
+				mkdir($cacheDir, 0770, true);
+			}
+
+			return [
+				new MountPoint('\OC\Files\Storage\Local', '/' . $user->getUID() . '/cache', ['datadir' => $cacheDir, $loader])
+			];
+		} else {
+			return [];
+		}
+	}
+}