Merge pull request #8032 from owncloud/fs-backend-registration

Files External: allow dynamic backend registration

10 files changed, 462 insertions, 166 deletions

diff --git a/apps/files_external/appinfo/app.php b/apps/files_external/appinfo/app.php
index aeb7a2cb23a..0017b22caad 100644
--- a/apps/files_external/appinfo/app.php
+++ b/apps/files_external/appinfo/app.php
@@ -31,3 +31,136 @@ OCP\Util::connectHook('OC_Filesystem', 'post_initMountPoints', '\OC_Mount_Config
 OCP\Util::connectHook('OC_User', 'post_login', 'OC\Files\Storage\iRODS', 'login');
 OCP\Util::connectHook('OC_User', 'post_login', 'OC\Files\Storage\SMB_OC', 'login');
 
+OC_Mount_Config::registerBackend('\OC\Files\Storage\Local', array(
+	'backend' => 'Local',
+	'configuration' => array(
+		'datadir' => 'Location')));
+
+OC_Mount_Config::registerBackend('\OC\Files\Storage\AmazonS3', array(
+	'backend' => 'Amazon S3',
+	'configuration' => array(
+		'key' => 'Key',
+		'secret' => '*Secret',
+		'bucket' => 'Bucket'),
+	'has_dependencies' => true));
+
+OC_Mount_Config::registerBackend('\OC\Files\Storage\AmazonS3', array(
+	'backend' => 'Amazon S3 and compliant',
+	'configuration' => array(
+		'key' => 'Access Key',
+		'secret' => '*Secret Key',
+		'bucket' => 'Bucket',
+		'hostname' => '&Hostname (optional)',
+		'port' => '&Port (optional)',
+		'region' => '&Region (optional)',
+		'use_ssl' => '!Enable SSL',
+		'use_path_style' => '!Enable Path Style'),
+	'has_dependencies' => true));
+
+OC_Mount_Config::registerBackend('\OC\Files\Storage\Dropbox', array(
+	'backend' => 'Dropbox',
+	'configuration' => array(
+		'configured' => '#configured',
+		'app_key' => 'App key',
+		'app_secret' => '*App secret',
+		'token' => '#token',
+		'token_secret' => '#token_secret'),
+	'custom' => 'dropbox',
+	'has_dependencies' => true));
+
+OC_Mount_Config::registerBackend('\OC\Files\Storage\FTP', array(
+	'backend' => 'FTP',
+	'configuration' => array(
+		'host' => 'URL',
+		'user' => 'Username',
+		'password' => '*Password',
+		'root' => '&Root',
+		'secure' => '!Secure ftps://'),
+	'has_dependencies' => true));
+
+OC_Mount_Config::registerBackend('\OC\Files\Storage\Google', array(
+	'backend' => 'Google Drive',
+	'configuration' => array(
+		'configured' => '#configured',
+		'client_id' => 'Client ID',
+		'client_secret' => '*Client secret',
+		'token' => '#token'),
+	'custom' => 'google',
+	'has_dependencies' => true));
+
+
+OC_Mount_Config::registerBackend('\OC\Files\Storage\Swift', array(
+	'backend' => 'OpenStack Object Storage',
+	'configuration' => array(
+		'user' => 'Username (required)',
+		'bucket' => 'Bucket (required)',
+		'region' => '&Region (optional for OpenStack Object Storage)',
+		'key' => '*API Key (required for Rackspace Cloud Files)',
+		'tenant' => '&Tenantname (required for OpenStack Object Storage)',
+		'password' => '*Password (required for OpenStack Object Storage)',
+		'service_name' => '&Service Name (required for OpenStack Object Storage)',
+		'url' => '&URL of identity endpoint (required for OpenStack Object Storage)',
+		'timeout' => '&Timeout of HTTP requests in seconds (optional)',
+	),
+	'has_dependencies' => true));
+
+
+if (!OC_Util::runningOnWindows()) {
+	OC_Mount_Config::registerBackend('\OC\Files\Storage\SMB', array(
+		'backend' => 'SMB / CIFS',
+		'configuration' => array(
+			'host' => 'URL',
+			'user' => 'Username',
+			'password' => '*Password',
+			'share' => 'Share',
+			'root' => '&Root'),
+		'has_dependencies' => true));
+
+	OC_Mount_Config::registerBackend('\OC\Files\Storage\SMB_OC', array(
+			'backend' => 'SMB / CIFS using OC login',
+			'configuration' => array(
+				'host' => 'URL',
+				'username_as_share' => '!Username as share',
+				'share' => '&Share',
+				'root' => '&Root'),
+		'has_dependencies' => true));
+}
+
+OC_Mount_Config::registerBackend('\OC\Files\Storage\DAV', array(
+	'backend' => 'WebDAV',
+	'configuration' => array(
+		'host' => 'URL',
+		'user' => 'Username',
+		'password' => '*Password',
+		'root' => '&Root',
+		'secure' => '!Secure https://'),
+	'has_dependencies' => true));
+
+OC_Mount_Config::registerBackend('\OC\Files\Storage\OwnCloud', array(
+	'backend' => 'ownCloud',
+	'configuration' => array(
+		'host' => 'URL',
+		'user' => 'Username',
+		'password' => '*Password',
+		'root' => '&Remote subfolder',
+		'secure' => '!Secure https://')));
+
+
+OC_Mount_Config::registerBackend('\OC\Files\Storage\SFTP', array(
+	'backend' => 'SFTP',
+	'configuration' => array(
+		'host' => 'URL',
+		'user' => 'Username',
+		'password' => '*Password',
+		'root' => '&Root')));
+
+OC_Mount_Config::registerBackend('\OC\Files\Storage\iRODS', array(
+	'backend' => 'iRODS',
+	'configuration' => array(
+		'host' => 'Host',
+		'port' => 'Port',
+		'use_logon_credentials' => '!Use ownCloud login',
+		'user' => 'Username',
+		'password' => '*Password',
+		'auth_mode' => 'Authentication Mode',
+		'zone' => 'Zone')));
diff --git a/apps/files_external/lib/amazons3.php b/apps/files_external/lib/amazons3.php
index 06ccd5d16fa..2093fb7e58c 100644
--- a/apps/files_external/lib/amazons3.php
+++ b/apps/files_external/lib/amazons3.php
@@ -548,4 +548,16 @@ class AmazonS3 extends \OC\Files\Storage\Common {
 			return false;
 		}
 	}
+
+	/**
+	 * check if curl is installed
+	 */
+	public static function checkDependencies() {
+		if (function_exists('curl_init')) {
+			return true;
+		} else {
+			return array('curl');
+		}
+	}
+
 }
diff --git a/apps/files_external/lib/config.php b/apps/files_external/lib/config.php
index 472c3963d51..613f0b2609c 100755
--- a/apps/files_external/lib/config.php
+++ b/apps/files_external/lib/config.php
@@ -39,6 +39,34 @@ class OC_Mount_Config {
 	// whether to skip backend test (for unit tests, as this static class is not mockable)
 	public static $skipTest = false;
 
+	private static $backends = array();
+
+	/**
+	 * @param string $class
+	 * @param array $definition
+	 * @return bool
+	 */
+	public static function registerBackend($class, $definition) {
+		if (!isset($definition['backend'])) {
+			return false;
+		}
+
+		OC_Mount_Config::$backends[$class] = $definition;
+		return true;
+	}
+
+	/**
+	 * Setup backends
+	 *
+	 * @return array of previously registered backends
+	 */
+	public static function setUp($backends = array()) {
+		$backup = self::$backends;
+		self::$backends = $backends;
+
+		return $backup;
+	}
+
 	/**
 	* Get details on each of the external storage backends, used for the mount config UI
 	* If a custom UI is needed, add the key 'custom' and a javascript file with that name will be loaded
@@ -46,132 +74,32 @@ class OC_Mount_Config {
 	* If the configuration parameter is a boolean, add a '!' to the beginning of the value
 	* If the configuration parameter is optional, add a '&' to the beginning of the value
 	* If the configuration parameter is hidden, add a '#' to the beginning of the value
-	* @return string
+	* @return array
 	*/
 	public static function getBackends() {
-
-		// FIXME: do not rely on php key order for the options order in the UI
-		$backends['\OC\Files\Storage\Local']=array(
-				'backend' => 'Local',
-				'configuration' => array(
-					'datadir' => 'Location'));
-
-		$backends['\OC\Files\Storage\AmazonS3']=array(
-			'backend' => 'Amazon S3 and compliant',
-			'configuration' => array(
-				'key' => 'Access Key',
-				'secret' => '*Secret Key',
-				'bucket' => 'Bucket',
-				'hostname' => '&Hostname (optional)',
-				'port' => '&Port (optional)',
-				'region' => '&Region (optional)',
-				'use_ssl' => '!Enable SSL',
-				'use_path_style' => '!Enable Path Style'));
-
-		$backends['\OC\Files\Storage\Dropbox']=array(
-			'backend' => 'Dropbox',
-			'configuration' => array(
-				'configured' => '#configured',
-				'app_key' => 'App key',
-				'app_secret' => '*App secret',
-				'token' => '#token',
-				'token_secret' => '#token_secret'),
-				'custom' => 'dropbox');
-
-		if(OC_Mount_Config::checkphpftp()) $backends['\OC\Files\Storage\FTP']=array(
-			'backend' => 'FTP',
-			'configuration' => array(
-				'host' => 'Hostname',
-				'user' => 'Username',
-				'password' => '*Password',
-				'root' => '&Root',
-				'secure' => '!Secure ftps://'));
-
-		if(OC_Mount_Config::checkcurl()) $backends['\OC\Files\Storage\Google']=array(
-			'backend' => 'Google Drive',
-			'configuration' => array(
-				'configured' => '#configured',
-				'client_id' => 'Client ID',
-				'client_secret' => '*Client secret',
-				'token' => '#token'),
-				'custom' => 'google');
-
-		if(OC_Mount_Config::checkcurl()) {
-			$backends['\OC\Files\Storage\Swift'] = array(
-				'backend' => 'OpenStack Object Storage',
-				'configuration' => array(
-					'user' => 'Username (required)',
-					'bucket' => 'Bucket (required)',
-					'region' => '&Region (optional for OpenStack Object Storage)',
-					'key' => '*API Key (required for Rackspace Cloud Files)',
-					'tenant' => '&Tenantname (required for OpenStack Object Storage)',
-					'password' => '*Password (required for OpenStack Object Storage)',
-					'service_name' => '&Service Name (required for OpenStack Object Storage)',
-					'url' => '&URL of identity endpoint (required for OpenStack Object Storage)',
-					'timeout' => '&Timeout of HTTP requests in seconds (optional)',
-				)
-			);
-                }
-
-		if (!OC_Util::runningOnWindows()) {
-			if (OC_Mount_Config::checksmbclient()) {
-				$backends['\OC\Files\Storage\SMB'] = array(
-					'backend' => 'SMB / CIFS',
-					'configuration' => array(
-						'host' => 'URL',
-						'user' => 'Username',
-						'password' => '*Password',
-						'share' => 'Share',
-						'root' => '&Root'));
-				$backends['\OC\Files\Storage\SMB_OC'] = array(
-					'backend' => 'SMB / CIFS using OC login',
-					'configuration' => array(
-						'host' => 'URL',
-						'username_as_share' => '!Username as share',
-						'share' => '&Share',
-						'root' => '&Root'));
+		$sortFunc = function($a, $b) {
+			return strcasecmp($a['backend'], $b['backend']);
+		};
+
+		$backEnds = array();
+
+		foreach (OC_Mount_Config::$backends as $class => $backend) {
+			if (isset($backend['has_dependencies']) and $backend['has_dependencies'] === true) {
+				if (!method_exists($class, 'checkDependencies')) {
+					\OCP\Util::writeLog('files_external',
+						"Backend class $class has dependencies but doesn't provide method checkDependencies()",
+						\OCP\Util::DEBUG);
+					continue;
+				} elseif ($class::checkDependencies() !== true) {
+					continue;
+				}
 			}
+			$backEnds[$class] = $backend;
 		}
 
-		if(OC_Mount_Config::checkcurl()){
-			$backends['\OC\Files\Storage\DAV']=array(
-				'backend' => 'WebDAV',
-				'configuration' => array(
-					'host' => 'URL',
-					'user' => 'Username',
-					'password' => '*Password',
-					'root' => '&Root',
-					'secure' => '!Secure https://'));
-			$backends['\OC\Files\Storage\OwnCloud']=array(
-				'backend' => 'ownCloud',
-				'configuration' => array(
-					'host' => 'URL',
-					'user' => 'Username',
-					'password' => '*Password',
-					'root' => '&Remote subfolder',
-					'secure' => '!Secure https://'));
-		}
-
-		$backends['\OC\Files\Storage\SFTP']=array(
-			'backend' => 'SFTP',
-			'configuration' => array(
-				'host' => 'URL',
-				'user' => 'Username',
-				'password' => '*Password',
-				'root' => '&Root'));
-
-		$backends['\OC\Files\Storage\iRODS']=array(
-			'backend' => 'iRODS',
-			'configuration' => array(
-				'host' => 'Host',
-				'port' => 'Port',
-				'use_logon_credentials' => '!Use ownCloud login',
-				'user' => 'Username',
-				'password' => '*Password',
-				'auth_mode' => 'Authentication Mode',
-				'zone' => 'Zone'));
-
-		return($backends);
+		uasort($backEnds, $sortFunc);
+
+		return $backEnds;
 	}
 
 	/**
@@ -278,19 +206,19 @@ class OC_Mount_Config {
 	*/
 	public static function getPersonalBackends() {
 
-		$backends = self::getBackends();
+		$backEnds = self::getBackends();
 
 		// Remove local storage and other disabled storages
-		unset($backends['\OC\Files\Storage\Local']);
+		unset($backEnds['\OC\Files\Storage\Local']);
 
-		$allowed_backends = explode(',', OCP\Config::getAppValue('files_external', 'user_mounting_backends', ''));
-		foreach ($backends as $backend => $null) {
-			if (!in_array($backend, $allowed_backends)) {
-				unset($backends[$backend]);
+		$allowedBackEnds = explode(',', OCP\Config::getAppValue('files_external', 'user_mounting_backends', ''));
+		foreach ($backEnds as $backend => $null) {
+			if (!in_array($backend, $allowedBackEnds)) {
+				unset($backEnds[$backend]);
 			}
 		}
 
-		return $backends;
+		return $backEnds;
 	}
 
 	/**
@@ -373,7 +301,7 @@ class OC_Mount_Config {
 	*/
 	public static function getPersonalMountPoints() {
 		$mountPoints = self::readData(true);
-		$backends = self::getBackends();
+		$backEnds = self::getBackends();
 		$uid = OCP\User::getUser();
 		$personal = array();
 		if (isset($mountPoints[self::MOUNT_TYPE_USER][$uid])) {
@@ -387,7 +315,7 @@ class OC_Mount_Config {
 					'class' => $mount['class'],
 					// Remove '/uid/files/' from mount point
 					'mountpoint' => substr($mountPoint, strlen($uid) + 8),
-					'backend' => $backends[$mount['class']]['backend'],
+					'backend' => $backEnds[$mount['class']]['backend'],
 					'options' => $mount['options'],
 					'status' => self::getBackendStatus($mount['class'], $mount['options'], true)
 				);
@@ -614,54 +542,91 @@ class OC_Mount_Config {
 	}
 
 	/**
-	 * check if smbclient is installed
+	 * check dependencies
 	 */
-	public static function checksmbclient() {
-		if(function_exists('shell_exec')) {
-			$output=shell_exec('command -v smbclient 2> /dev/null');
-			return !empty($output);
-		}else{
-			return false;
+	public static function checkDependencies() {
+		$dependencies = array();
+		foreach (OC_Mount_Config::$backends as $class => $backend) {
+			if (isset($backend['has_dependencies']) and $backend['has_dependencies'] === true) {
+				$result = $class::checkDependencies();
+				if ($result !== true) {
+					if (!is_array($result)) {
+						$result = array($result);
+					}
+					foreach ($result as $key => $value) {
+						if (is_numeric($key)) {
+							OC_Mount_Config::addDependency($dependencies, $value, $backend['backend']);
+						} else {
+							OC_Mount_Config::addDependency($dependencies, $key, $backend['backend'], $value);
+						}
+					}
+				}
+			}
+		}
+
+		if (count($dependencies) > 0) {
+			return OC_Mount_Config::generateDependencyMessage($dependencies);
 		}
+		return '';
 	}
 
-	/**
-	 * check if php-ftp is installed
-	 */
-	public static function checkphpftp() {
-		if(function_exists('ftp_login')) {
-			return true;
-		}else{
-			return false;
+	private static function addDependency(&$dependencies, $module, $backend, $message=null) {
+		if (!isset($dependencies[$module])) {
+			$dependencies[$module] = array();
+		}
+
+		if ($message === null) {
+			$dependencies[$module][] = $backend;
+		} else {
+			$dependencies[$module][] = array('backend' => $backend, 'message' => $message);
 		}
 	}
 
-	/**
-	 * check if curl is installed
-	 */
-	public static function checkcurl() {
-		return function_exists('curl_init');
+	private static function generateDependencyMessage($dependencies) {
+		$l = new \OC_L10N('files_external');
+		$dependencyMessage = '';
+		foreach ($dependencies as $module => $backends) {
+			$dependencyGroup = array();
+			foreach ($backends as $backend) {
+				if (is_array($backend)) {
+					$dependencyMessage .= '<br />' . $l->t('<b>Note:</b> ') . $backend['message'];
+				} else {
+					$dependencyGroup[] = $backend;
+				}
+			}
+
+			if (count($dependencyGroup) > 0) {
+				$backends = '';
+				for ($i = 0; $i < count($dependencyGroup); $i++) {
+					if ($i > 0 && $i === count($dependencyGroup) - 1) {
+						$backends .= $l->t(' and ');
+					} elseif ($i > 0) {
+						$backends .= ', ';
+					}
+					$backends .= '<i>' . $dependencyGroup[$i] . '</i>';
+				}
+				$dependencyMessage .= '<br />' . OC_Mount_Config::getSingleDependencyMessage($l, $module, $backends);
+			}
+		}
+		return $dependencyMessage;
 	}
 
 	/**
-	 * check dependencies
+	 * Returns a dependency missing message
+	 * @param $l OC_L10N
+	 * @param $module string
+	 * @param $backend string
+	 * @return string
 	 */
-	public static function checkDependencies() {
-		$l= new OC_L10N('files_external');
-		$txt='';
-		if (!OC_Util::runningOnWindows()) {
-			if(!OC_Mount_Config::checksmbclient()) {
-				$txt.=$l->t('<b>Warning:</b> "smbclient" is not installed. Mounting of CIFS/SMB shares is not possible. Please ask your system administrator to install it.').'<br />';
-			}
+	private static function getSingleDependencyMessage($l, $module, $backend) {
+		switch (strtolower($module)) {
+			case 'curl':
+				return $l->t('<b>Note:</b> The cURL support in PHP is not enabled or installed. Mounting of %s is not possible. Please ask your system administrator to install it.', $backend);
+			case 'ftp':
+				return $l->t('<b>Note:</b> The FTP support in PHP is not enabled or installed. Mounting of %s is not possible. Please ask your system administrator to install it.', $backend);
+			default:
+				return $l->t('<b>Note:</b> "%s" is not installed. Mounting of %s is not possible. Please ask your system administrator to install it.', array($module, $backend));
 		}
-		if(!OC_Mount_Config::checkphpftp()) {
-			$txt.=$l->t('<b>Warning:</b> The FTP support in PHP is not enabled or installed. Mounting of FTP shares is not possible. Please ask your system administrator to install it.').'<br />';
-		}
-		if(!OC_Mount_Config::checkcurl()) {
-			$txt.=$l->t('<b>Warning:</b> The Curl support in PHP is not enabled or installed. Mounting of ownCloud / WebDAV or GoogleDrive is not possible. Please ask your system administrator to install it.').'<br />';
-		}
-
-		return $txt;
 	}
 
 	/**
diff --git a/apps/files_external/lib/dropbox.php b/apps/files_external/lib/dropbox.php
index 0214e18020c..38de3360f2b 100755
--- a/apps/files_external/lib/dropbox.php
+++ b/apps/files_external/lib/dropbox.php
@@ -311,4 +311,15 @@ class Dropbox extends \OC\Files\Storage\Common {
 		return true;
 	}
 
+	/**
+	 * check if curl is installed
+	 */
+	public static function checkDependencies() {
+		if (function_exists('curl_init')) {
+			return true;
+		} else {
+			return array('curl');
+		}
+	}
+
 }
diff --git a/apps/files_external/lib/ftp.php b/apps/files_external/lib/ftp.php
index 00bf7a189ce..b3f8b1444ae 100644
--- a/apps/files_external/lib/ftp.php
+++ b/apps/files_external/lib/ftp.php
@@ -119,4 +119,16 @@ class FTP extends \OC\Files\Storage\StreamWrapper{
 			unlink($tmpFile);
 		}
 	}
+
+	/**
+	 * check if php-ftp is installed
+	 */
+	public static function checkDependencies() {
+		if (function_exists('ftp_login')) {
+			return(true);
+		} else {
+			return array('ftp');
+		}
+	}
+
 }
diff --git a/apps/files_external/lib/google.php b/apps/files_external/lib/google.php
index 35457f68528..56c0d451651 100644
--- a/apps/files_external/lib/google.php
+++ b/apps/files_external/lib/google.php
@@ -586,4 +586,15 @@ class Google extends \OC\Files\Storage\Common {
 		return false;
 	}
 
+	/**
+	 * check if curl is installed
+	 */
+	public static function checkDependencies() {
+		if (function_exists('curl_init')) {
+			return true;
+		} else {
+			return array('curl');
+		}
+	}
+
 }
diff --git a/apps/files_external/lib/smb.php b/apps/files_external/lib/smb.php
index f3f3b3ed7f3..b1d355323d9 100644
--- a/apps/files_external/lib/smb.php
+++ b/apps/files_external/lib/smb.php
@@ -134,4 +134,18 @@ class SMB extends \OC\Files\Storage\StreamWrapper{
 		}
 		return $lastCtime;
 	}
+
+	/**
+	 * check if smbclient is installed
+	 */
+	public static function checkDependencies() {
+		if (function_exists('shell_exec')) {
+			$output=shell_exec('command -v smbclient 2> /dev/null');
+			if (!empty($output)) {
+				return true;
+			}
+		}
+		return array('smbclient');
+	}
+
 }
diff --git a/apps/files_external/lib/swift.php b/apps/files_external/lib/swift.php
index 1337d9f581d..a202d3843cb 100644
--- a/apps/files_external/lib/swift.php
+++ b/apps/files_external/lib/swift.php
@@ -65,6 +65,18 @@ class Swift extends \OC\Files\Storage\Common {
 		return $path;
 	}
 
+	const SUBCONTAINER_FILE='.subcontainers';
+
+	/**
+	 * translate directory path to container name
+	 * @param string $path
+	 * @return string
+	 */
+	private function getContainerName($path) {
+		$path=trim(trim($this->root, '/') . "/".$path, '/.');
+		return str_replace('/', '\\', $path);
+	}
+
 	/**
 	 * @param string $path
 	 */
@@ -490,4 +502,16 @@ class Swift extends \OC\Files\Storage\Common {
 		), $tmpFile);
 		unlink($tmpFile);
 	}
+
+	/**
+	 * check if curl is installed
+	 */
+	public static function checkDependencies() {
+		if (function_exists('curl_init')) {
+			return true;
+		} else {
+			return array('curl');
+		}
+	}
+
 }
diff --git a/apps/files_external/lib/webdav.php b/apps/files_external/lib/webdav.php
index f5010f92208..dc98dcfb808 100644
--- a/apps/files_external/lib/webdav.php
+++ b/apps/files_external/lib/webdav.php
@@ -385,5 +385,16 @@ class DAV extends \OC\Files\Storage\Common {
 			return false;
 		}
 	}
+
+	/**
+	 * check if curl is installed
+	 */
+	public static function checkDependencies() {
+		if (function_exists('curl_init')) {
+			return true;
+		} else {
+			return array('curl');
+		}
+	}
 }
 
diff --git a/apps/files_external/tests/dynamicmountconfig.php b/apps/files_external/tests/dynamicmountconfig.php
new file mode 100644
index 00000000000..81a31e14c60
--- /dev/null
+++ b/apps/files_external/tests/dynamicmountconfig.php
@@ -0,0 +1,103 @@
+<?php
+/**
+ * ownCloud
+ *
+ * @author Thomas Müller
+ * Copyright (c) 2014 Thomas Müller <deepdiver@owncloud.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This library 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 library.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+require_once __DIR__ . '/../../../lib/base.php';
+
+require __DIR__ . '/../lib/config.php';
+
+/**
+ * Class Test_Mount_Config_Dummy_Backend
+ */
+class Test_Mount_Config_Dummy_Backend {
+	public static $checkDependencies = true;
+
+	public static function checkDependencies() {
+		return self::$checkDependencies;
+	}
+}
+
+/**
+ * Class Test_Dynamic_Mount_Config
+ */
+class Test_Dynamic_Mount_Config extends \PHPUnit_Framework_TestCase {
+
+	private $backup;
+
+	public function testRegistration() {
+
+		// second registration shall return false
+		$result = OC_Mount_Config::registerBackend('Test_Mount_Config_Dummy_Backend', array(
+			'backend' => 'Test Dummy',
+			'configuration' => array(),
+			'has_dependencies' => true));
+
+		$this->assertTrue($result);
+	}
+
+	public function testDependencyGetBackend() {
+
+		// is the backend listed?
+		Test_Mount_Config_Dummy_Backend::$checkDependencies = true;
+		$backEnds = OC_Mount_Config::getBackends();
+		$this->assertArrayHasKey('Test_Mount_Config_Dummy_Backend', $backEnds);
+
+		// backend shall not be listed
+		Test_Mount_Config_Dummy_Backend::$checkDependencies = false;
+
+		$backEnds = OC_Mount_Config::getBackends();
+		$this->assertArrayNotHasKey('Test_Mount_Config_Dummy_Backend', $backEnds);
+
+	}
+
+	public function testCheckDependencies() {
+
+		Test_Mount_Config_Dummy_Backend::$checkDependencies = true;
+		$message = OC_Mount_Config::checkDependencies();
+		$this->assertEmpty($message);
+
+		// backend shall not be listed
+		Test_Mount_Config_Dummy_Backend::$checkDependencies = array('dummy');
+
+		$message = OC_Mount_Config::checkDependencies();
+		$this->assertEquals('<br /><b>Note:</b> "dummy" is not installed. Mounting of <i>Test Dummy</i> is not possible. Please ask your system administrator to install it.',
+			$message);
+
+	}
+
+	protected function setUp() {
+
+		$this->backup = OC_Mount_Config::setUp();
+
+		// register dummy backend
+		$result = OC_Mount_Config::registerBackend('Test_Mount_Config_Dummy_Backend', array(
+			'backend' => 'Test Dummy',
+			'configuration' => array(),
+			'has_dependencies' => true));
+
+		$this->assertTrue($result);
+	}
+
+	protected function tearDown()
+	{
+		OC_Mount_Config::setUp($this->backup);
+	}
+}