Thows exception if password not available

Signed-off-by: Morris Jobke <hey@morrisjobke.de>

lib/public/Authentication/Exceptions/PasswordUnavailableException.php

@@ -0,0 +1,34 @@
+<?php
+
+/**
+ * @copyright 2017 Morris Jobke <hey@morrisjobke.de>
+ *
+ * @author 2017 Morris Jobke <hey@morrisjobke.de>
+ *
+ * @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 OCP\Authentication\Exceptions;
+
+use Exception;
+
+/**
+ * @since 12
+ */
+class PasswordUnavailableException extends Exception {
+
+}

lib/public/Authentication/LoginCredentials/ICredentials.php

@@ -24,6 +24,8 @@
 
 namespace OCP\Authentication\LoginCredentials;
 
+use OCP\Authentication\Exceptions\PasswordUnavailableException;
+
 /**
  * @since 12
  */
@@ -53,6 +55,7 @@ interface ICredentials {
 	 * @since 12
 	 *
 	 * @return string
+	 * @throws PasswordUnavailableException
 	 */
 	public function getPassword();
 }