GUACAMOLE-1756: Display login failures regardless of whether the interactive login form was used.

guacamole/src/main/frontend/src/app/index/controllers/indexController.js

@@ -35,6 +35,7 @@ angular.module('index').controller('indexController', ['$scope', '$injector',
     const SESSION_VALIDITY_RECHECK_INTERVAL = 15000;
 
     // Required types
+    const Error              = $injector.get('Error');
     const ManagedClientState = $injector.get('ManagedClientState');
 
     // Required services
@@ -110,6 +111,11 @@ angular.module('index').controller('indexController', ['$scope', '$injector',
      */
     var ApplicationState = {
 
+        /**
+         * A non-interactive authentication attempt failed.
+         */
+        AUTOMATIC_LOGIN_REJECTED : 'automaticLoginRejected',
+
         /**
          * The application has fully loaded but is awaiting credentials from
          * the user before proceeding.
@@ -323,6 +329,25 @@ angular.module('index').controller('indexController', ['$scope', '$injector',
 
     });
 
+    // Alert user to authentication errors that occur in the absence of an
+    // interactive login form
+    $scope.$on('guacLoginFailed', function loginFailed(event, parameters, error) {
+
+        // All errors related to an interactive login form are handled elsewhere
+        if ($scope.applicationState === ApplicationState.AWAITING_CREDENTIALS
+                || error.type === Error.Type.INSUFFICIENT_CREDENTIALS
+                || error.type === Error.Type.INVALID_CREDENTIALS)
+            return;
+
+        $scope.applicationState = ApplicationState.AUTOMATIC_LOGIN_REJECTED;
+        $scope.page.title = 'APP.NAME';
+        $scope.page.bodyClassName = '';
+
+        $scope.reAuthenticating = false;
+        $scope.fatalError = error;
+
+    });
+
     // Replace absolutely all content with an error message if the page itself
     // cannot be displayed due to an error
     $scope.$on('guacFatalPageError', function fatalPageError(error) {

guacamole/src/main/frontend/src/app/index/styles/automatic-login-rejected.css

@@ -0,0 +1,30 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+.automatic-login-rejected-modal guac-modal {
+    background: white;
+    z-index: 20;
+}
+
+.automatic-login-rejected-modal .notification {
+    display: inline-block;
+    max-width: 5in;
+    padding: 1em;
+    width: 100%;
+}

guacamole/src/main/frontend/src/index.html

@@ -64,6 +64,20 @@
             </guac-modal>
         </div>
 
+        <!-- Authentication error without a corresponding login form -->
+        <div class="automatic-login-rejected-modal" ng-switch-when="automaticLoginRejected">
+            <guac-modal>
+                <div class="notification">
+                    <p translate="{{ fatalError.translatableMessage.key }}"
+                       translate-values="{{ fatalError.translatableMessage.variables }}"></p>
+                    <p>
+                        <button translate="APP.ACTION_LOGIN_AGAIN" ng-disabled="reAuthenticating"
+                                ng-click="reAuthenticate()"></button>
+                    </p>
+                </div>
+            </guac-modal>
+        </div>
+
         <!-- Login screen for logged-out users -->
         <guac-login ng-switch-when="awaitingCredentials"
                     help-text="loginHelpText"