ApplicationRoles.create should accept permission set names

atst/domain/application_roles.py

@@ -1,13 +1,20 @@
 from atst.database import db
 from atst.models.application_role import ApplicationRole
+from atst.domain.permission_sets import PermissionSets
 
 
 class ApplicationRoles(object):
     @classmethod
-    def create(cls, user, application, permission_sets):
+    def _permission_sets_for_names(cls, set_names):
+        return PermissionSets.get_many(set_names)
+
+    @classmethod
+    def create(cls, user, application, permission_set_names):
         application_role = ApplicationRole(user=user, application_id=application.id)
 
-        application_role.permission_sets = permission_sets
+        application_role.permission_sets = ApplicationRoles._permission_sets_for_names(
+            permission_set_names
+        )
 
         db.session.add(application_role)
         db.session.commit()