feat(titus): Support rollback of disabled server groups (parity with …

…aws) (#5100)

If only one possible server group exists as a rollback target, it will be
selected by default.

See #5077

app/scripts/modules/amazon/src/serverGroup/details/AmazonServerGroupActions.tsx

@@ -179,13 +179,18 @@ export class AmazonServerGroupActions extends React.Component<IAmazonServerGroup
        */
       serverGroup = orderBy(
         allServerGroups.filter((g: IAmazonServerGroup) => g.name !== previousServerGroup.name && !g.isDisabled),
-        ['instanceCounts.total'], ['desc']
+        ['instanceCounts.total', 'createdTime'], ['desc', 'desc']
       )[0] as IAmazonServerGroup;
     }
 
     // the set of all server groups should not include the server group selected for rollback
     allServerGroups = allServerGroups.filter((g: IAmazonServerGroup) => g.name !== serverGroup.name);
 
+    if (allServerGroups.length === 1 && !previousServerGroup) {
+      // if there is only one other server group, default to it being the rollback target
+      previousServerGroup = allServerGroups[0];
+    }
+
     ReactInjector.modalService.open({
       templateUrl: ReactInjector.overrideRegistry.getTemplate('aws.rollback.modal', require('./rollback/rollbackServerGroup.html')),
       controller: 'awsRollbackServerGroupCtrl as ctrl',

app/scripts/modules/titus/src/serverGroup/details/rollback/rollbackServerGroup.controller.js

@@ -11,7 +11,9 @@ module.exports = angular.module('spinnaker.titus.serverGroup.details.rollback.co
 ])
   .controller('titusRollbackServerGroupCtrl', function ($scope, $uibModalInstance, serverGroupWriter,
                                                         taskMonitorBuilder,
-                                                        application, serverGroup, disabledServerGroups, allServerGroups) {
+                                                        application,
+                                                        serverGroup, previousServerGroup,
+                                                        disabledServerGroups, allServerGroups) {
     $scope.serverGroup = serverGroup;
     $scope.disabledServerGroups = disabledServerGroups.sort((a, b) => b.name.localeCompare(a.name));
     $scope.allServerGroups = allServerGroups.sort((a, b) => b.name.localeCompare(a.name));
@@ -49,6 +51,7 @@ module.exports = angular.module('spinnaker.titus.serverGroup.details.rollback.co
       rollbackType: rollbackType,
       rollbackContext: {
         rollbackServerGroupName: serverGroup.name,
+        restoreServerGroupName: previousServerGroup ? previousServerGroup.name : undefined,
         targetHealthyRollbackPercentage: healthyPercent
       }
     };

app/scripts/modules/titus/src/serverGroup/details/rollback/rollbackServerGroup.html

@@ -10,7 +10,7 @@ <h3>Rollback {{serverGroup.name}}</h3>
         <div class="col-sm-3 sm-label-right">
           Restore to
         </div>
-        <div class="col-sm-8">
+        <div class="col-sm-7">
           <ui-select ng-model="command.rollbackContext.restoreServerGroupName"
                      class="form-control input-sm"
                      ng-if="command.rollbackType === 'EXPLICIT'">
@@ -39,9 +39,7 @@ <h3>Rollback {{serverGroup.name}}</h3>
         </div>
       </div>
 
-      <div class="row">
-        <task-reason command="command"></task-reason>
-      </div>
+      <task-reason command="command"></task-reason>
 
       <div class="row">
         <div class="col-sm-11 col-sm-offset-1">

app/scripts/modules/titus/src/serverGroup/details/serverGroupDetails.html

@@ -42,8 +42,8 @@ <h3 select-on-dbl-click>
             Titus Job Actions <span class="caret"></span>
           </button>
           <ul class="dropdown-menu" uib-dropdown-menu role="menu">
-            <li><a href ng-if=" !serverGroup.isDisabled" ng-click="ctrl.rollbackServerGroup()">Rollback</a></li>
-            <li role="presentation" class="divider" ng-if="!serverGroup.isDisabled"></li>
+            <li><a href ng-if="ctrl.isRollbackEnabled()" ng-click="ctrl.rollbackServerGroup()">Rollback</a></li>
+            <li role="presentation" class="divider" ng-if="ctrl.isRollbackEnabled()"></li>
             <li><a href ng-click="ctrl.resizeServerGroup()">Resize</a></li>
             <li><a href ng-if="!serverGroup.isDisabled" ng-click="ctrl.disableServerGroup()">Disable</a></li>
             <li><a href ng-if="serverGroup.isDisabled" ng-click="ctrl.enableServerGroup()">Enable</a></li>

app/scripts/modules/titus/src/serverGroup/details/serverGroupDetails.titus.controller.js

@@ -311,23 +311,71 @@ module.exports = angular.module('spinnaker.serverGroup.details.titus.controller'
       });
     };
 
+    this.isRollbackEnabled = function rollbackServerGroup() {
+      let serverGroup = $scope.serverGroup;
+      if (!serverGroup.isDisabled) {
+        // enabled server groups are always a candidate for rollback
+        return true;
+      }
+
+      // if the server group selected for rollback is disabled, ensure that at least one enabled server group exists
+      return application.getDataSource('serverGroups').data.some(g =>
+        g.cluster === serverGroup.cluster &&
+        g.region === serverGroup.region &&
+        g.account === serverGroup.account &&
+        g.isDisabled === false
+      );
+    };
+
     this.rollbackServerGroup = function rollbackServerGroup() {
-      var serverGroup = $scope.serverGroup;
+      let serverGroup = $scope.serverGroup;
+
+      let previousServerGroup;
+      let allServerGroups = app.getDataSource('serverGroups').data.filter(g =>
+        g.cluster === serverGroup.cluster &&
+        g.region === serverGroup.region &&
+        g.account === serverGroup.account
+      );
+
+      if (serverGroup.isDisabled) {
+        // if the selected server group is disabled, it represents the server group that should be _rolled back to_
+        previousServerGroup = serverGroup;
+
+        /*
+         * Find an existing server group to rollback, prefer the largest enabled server group.
+         *
+         * isRollbackEnabled() ensures that at least one enabled server group exists.
+         */
+        serverGroup = _.orderBy(
+          allServerGroups.filter(g =>
+            g.name !== previousServerGroup.name && !g.isDisabled
+          ),
+          ['instanceCounts.total', 'createdTime'],
+          ['desc', 'desc']
+        )[0];
+      }
+
+      // the set of all server groups should not include the server group selected for rollback
+      allServerGroups = allServerGroups.filter(g =>
+        g.name !== serverGroup.name
+      );
+
+      if (allServerGroups.length === 1 && !previousServerGroup) {
+        // if there is only one other server group, default to it being the rollback target
+        previousServerGroup = allServerGroups[0];
+      }
+
       $uibModal.open({
         templateUrl: require('./rollback/rollbackServerGroup.html'),
         controller: 'titusRollbackServerGroupCtrl as ctrl',
         resolve: {
           serverGroup: () => serverGroup,
+          previousServerGroup: () => previousServerGroup,
           disabledServerGroups: () => {
           var cluster = _.find(application.clusters, { name: serverGroup.cluster, account: serverGroup.account });
             return _.filter(cluster.serverGroups, { isDisabled: true, region: serverGroup.region });
           },
-          allServerGroups: () => application.getDataSource('serverGroups').data.filter(g =>
-            g.cluster === serverGroup.cluster &&
-            g.region === serverGroup.region &&
-            g.account === serverGroup.account &&
-            g.name !== serverGroup.name
-          ),
+          allServerGroups: () => allServerGroups,
           application: () => application
         }
       });