Show any last backup error

part of cloudron/box#797

src/views/app.html

@@ -201,7 +201,7 @@
         <p class="text-info">{{ 'app.importBackupDialog.description' | tr }}</p>
 
         <form name="importBackupForm" role="form" novalidate ng-submit="importBackup.submit()" autocomplete="off">
-          <p class="has-error text-center" ng-show="backups.error">{{ importBackup.error.generic }}</p>
+          <p class="has-error text-center" ng-show="importBackup.error">{{ importBackup.error.generic }}</p>
 
           <div class="form-group">
             <label class="control-label" for="storageProvider">{{ 'backups.configureBackupStorage.provider' | tr }} <sup><a ng-href="https://docs.cloudron.io/backups/#storage-providers" class="help" target="_blank"><i class="fa fa-question-circle"></i></a></sup></label>
@@ -1198,9 +1198,17 @@
             </table>
 
             <br/>
-            <button type="button" class="btn btn-primary pull-right" ng-click="backups.createBackup()" ng-disabled="app.taskId || backups.busyCreate || app.error || app.runState === 'stopped'" tooltip-enable="app.error || app.taskId || app.runState === 'stopped'" uib-tooltip="{{ app.error ? 'App is in error state' : 'App is not running' }}">
-              <i class="fa fa-circle-notch fa-spin" ng-show="app.installationState === 'pending_backup' || backups.busyCreate"></i> {{ 'app.backups.backups.createBackupAction' | tr }}
-            </button>
+
+            <div class="row">
+              <div class="col-md-6">
+                <p class="has-error" ng-show="backups.error.message">{{ backups.error.message }}</p>
+              </div>
+              <div class="col-md-6 text-right">
+                <button type="button" class="btn btn-primary pull-right" ng-click="backups.createBackup()" ng-disabled="app.taskId || backups.busyCreate || app.error || app.runState === 'stopped'" tooltip-enable="app.error || app.taskId || app.runState === 'stopped'" uib-tooltip="{{ app.error ? 'App is in error state' : 'App is not running' }}">
+                  <i class="fa fa-circle-notch fa-spin" ng-show="app.installationState === 'pending_backup' || backups.busyCreate"></i> {{ 'app.backups.backups.createBackupAction' | tr }}
+                </button>
+              </div>
+            </div>
 
           </div>
         </div>

src/views/app.js

@@ -1082,6 +1082,14 @@ angular.module('Application').controller('AppController', ['$scope', '$location'
                 if (error) return Client.error(error);
 
                 $scope.backups.backups = backups;
+
+                Client.getAppEventLog(app.id, 1, 1, function (error, result) {
+                    if (error) return console.error('Failed to get events:', error);
+
+                    if (result.length !== 0 && result[0].action == 'app.backup.finish') {
+                        $scope.backups.error.message = result[0].data.errorMessage;
+                    }
+                });
             });
         },