Disallow deleting controller or isolated instance groups

Added two new properties to the InstanceGroup model - `is_controller`
and `is_isolated`. Used these properties to hide the trash icon for
instance groups that are either controller or isolated.

Signed-off-by: Vismay Golwala <vgolwala@redhat.com>

awx/api/serializers.py

@@ -4881,6 +4881,15 @@ class InstanceGroupSerializer(BaseSerializer):
         read_only=True
     )
     instances = serializers.SerializerMethodField()
+    is_controller = serializers.BooleanField(
+        help_text=_('Indicates whether instance group controls any other group'),
+        read_only=True
+    )
+    is_isolated = serializers.BooleanField(
+        help_text=_('Indicates whether instances in this group are isolated.'
+                    'Isolated groups have a designated controller group.'),
+        read_only=True
+    )
     # NOTE: help_text is duplicated from field definitions, no obvious way of
     # both defining field details here and also getting the field's help_text
     policy_instance_percentage = serializers.IntegerField(
@@ -4906,7 +4915,7 @@ class InstanceGroupSerializer(BaseSerializer):
         fields = ("id", "type", "url", "related", "name", "created", "modified",
                   "capacity", "committed_capacity", "consumed_capacity",
                   "percent_capacity_remaining", "jobs_running", "jobs_total",
-                  "instances", "controller",
+                  "instances", "controller", "is_controller", "is_isolated",
                   "policy_instance_percentage", "policy_instance_minimum", "policy_instance_list")
 
     def get_related(self, obj):

awx/main/models/ha.py

@@ -208,6 +208,14 @@ class InstanceGroup(HasPolicyEditsMixin, BaseModel, RelatedJobsMixin):
     def jobs_total(self):
         return UnifiedJob.objects.filter(instance_group=self).count()
 
+    @property
+    def is_controller(self):
+        return self.controlled_groups.exists()
+
+    @property
+    def is_isolated(self):
+        return bool(self.controller)
+
     '''
     RelatedJobsMixin
     '''

awx/main/tests/functional/api/test_instance_group.py

@@ -78,6 +78,26 @@ def instance_group_jobs_successful(instance_group, create_job_factory, create_pr
     return jobs_successful + project_updates_successful
 
 
+@pytest.mark.django_db
+def test_instance_group_is_controller(instance_group, isolated_instance_group, non_iso_instance):
+    assert not isolated_instance_group.is_controller
+    assert instance_group.is_controller
+
+    instance_group.instances.set([non_iso_instance])
+
+    assert instance_group.is_controller
+
+
+@pytest.mark.django_db
+def test_instance_group_is_isolated(instance_group, isolated_instance_group):
+    assert not instance_group.is_isolated
+    assert isolated_instance_group.is_isolated
+
+    isolated_instance_group.instances = []
+
+    assert isolated_instance_group.is_isolated
+
+
 @pytest.mark.django_db
 def test_delete_instance_group_jobs(delete, instance_group_jobs_successful, instance_group, admin):
     url = reverse("api:instance_group_detail", kwargs={'pk': instance_group.pk})

awx/ui/client/src/instance-groups/list/instance-groups-list.controller.js

@@ -83,7 +83,7 @@ export default ['$scope', '$filter', '$state', 'Alert', 'resolvedModels', 'Datas
 
         vm.rowAction = {
             trash: instance_group => {
-                return vm.isSuperuser && instance_group.name !== 'tower';
+                return vm.isSuperuser && instance_group.name !== 'tower' && !instance_group.is_controller && !instance_group.is_isolated;
             }
         };