ONI-174: Add util to remove permission from a role. (#223)

core/utils.py

@@ -269,6 +269,20 @@ def insert_role_right_for_system(system_role, right_id):
     return role_right
 
 
+def remove_role_right_for_system(system_role, right_id):
+    RoleRight = apps.get_model("core", "RoleRight")
+    Role = apps.get_model("core", "Role")
+    existing_role = Role.objects.filter(is_system=system_role, validity_to__isnull=True).first()
+    if not existing_role:
+        logger.warning("Migration requested to remove a role_right for system role %s but couldn't find that role", system_role)
+    role_right = RoleRight.objects.filter(role=existing_role, right_id=right_id).first()
+    if role_right:
+        role_right.delete()
+        logger.info("Role right removed for system role %s and right ID %s", system_role, right_id)
+    else:
+        logger.warning("Role right not found for system role %s and right ID %s", system_role, right_id)
+
+
 def convert_to_python_value(string):
     try:
         value = ast.literal_eval(string)