If a role is already in a plan return a 409

Change-Id: Ib2eb78c554bc15e73d57a6fe83a69eb5afcf7456

tuskar/api/controllers/v2/roles.py

@@ -16,6 +16,7 @@ from pecan import rest
 from wsmeext import pecan as wsme_pecan
 
 from tuskar.api.controllers.v2 import models
+from tuskar.common import exception
 from tuskar.manager.plan import PlansManager
 from tuskar.manager.role import RoleManager
 
@@ -56,10 +57,20 @@ class RolesController(rest.RestController):
 
         :return: modified plan
         :rtype:  tuskar.api.controllers.v2.models.Plan
+
+        :raises: tuskar.common.exception.PlanAlreadyHasRole if the role has
+            already been added to the plan.
         """
         LOG.debug('Adding role: %s' % role.uuid)
         manager = PlansManager()
-        updated_plan = manager.add_role_to_plan(plan_uuid, role.uuid)
+        try:
+            updated_plan = manager.add_role_to_plan(plan_uuid, role.uuid)
+        except ValueError:
+            LOG.debug('The role has already been added to the plan.')
+            raise exception.PlanAlreadyHasRole(
+                plan_uuid=plan_uuid,
+                role_uuid=role.uuid
+            )
         transfer_plan = models.Plan.from_tuskar_model(updated_plan)
         return transfer_plan
 

tuskar/common/exception.py

@@ -197,3 +197,7 @@ class PlanNotFound(NotFound):
 
 class PlanExists(DuplicateEntry):
     message = _("Plan with name %(name)s already exists.")
+
+
+class PlanAlreadyHasRole(DuplicateEntry):
+    message = _("Plan %(plan_uuid)s already has role %(role_uuid)s.")

tuskar/tests/api/controllers/v2/test_roles.py

@@ -74,6 +74,20 @@ class RolesTests(base.TestCase):
         self.assertEqual(result['uuid'], 'a')
         self.assertEqual(result['name'], 'n')
 
+    @mock.patch('tuskar.manager.plan.PlansManager.add_role_to_plan')
+    def test_post_duplicate(self, mock_add):
+        # Setup
+        mock_add.side_effect = ValueError()
+
+        # Test
+        role_data = {'uuid': 'qwerty12345'}
+        response = self.app.post_json(URL_PLAN_ROLES, params=role_data,
+                                      status=409)
+
+        # Verify
+        mock_add.assert_called_once_with('plan_uuid', 'qwerty12345')
+        self.assertEqual(response.status_int, 409)
+
     @mock.patch('tuskar.manager.plan.PlansManager.remove_role_from_plan')
     def test_delete(self, mock_remove):
         # Setup