Check that provided class implements IStorage in StorageManager::setBackend

- Add notice in admin if setting value change failed
- Add notice in console if setting value change failed

mod/admin.php

@@ -1200,7 +1200,9 @@ function admin_page_site_post(App $a)
 	 * @var $storagebackend \Friendica\Model\Storage\IStorage
 	 */
 	$storagebackend    = Strings::escapeTags(trim(defaults($_POST, 'storagebackend', '')));
-	StorageManager::setBackend($storagebackend);
+	if (!StorageManager::setBackend($storagebackend)) {
+		info(L10n::t('Invalid storage backend setting value.'));
+	}
 
 	// save storage backend form
 	if (!is_null($storagebackend) && $storagebackend != "") {

src/Core/Console/Storage.php

@@ -106,7 +106,11 @@ HELP;
 			return -1;
 		}
 
-		StorageManager::setBackend($class);
+		if (!StorageManager::setBackend($class)) {
+			$this->out($class . ' is not a valid backend storage class.');
+			return -1;
+		}
+
 		return 0;
 	}
 

src/Core/StorageManager.php

@@ -54,12 +54,18 @@ class StorageManager
 	 * @brief Set current storage backend class
 	 *
 	 * @param string $class Backend class name
+	 * @return bool
 	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 	 */
 	public static function setBackend($class)
 	{
-		/// @todo Check that $class implements IStorage
+		if (!in_array('Friendica\Model\Storage\IStorage', class_implements($class))) {
+			return false;
+		}
+
 		Config::set('storage', 'class', $class);
+
+		return true;
 	}
 
 	/**