raise exception when trying to set unsupported column

diff --git a/PLC/Methods/UpdateTagType.py b/PLC/Methods/UpdateTagType.py
index 56bd61f..8fc868c 100644 (file)
--- a/PLC/Methods/UpdateTagType.py
+++ b/PLC/Methods/UpdateTagType.py
@@ -32,14 +32,21 @@ class UpdateTagType(Method):
     returns = Parameter(int, '1 if successful')
 
     def call(self, auth, tag_type_id_or_name, tag_type_fields):
-        tag_type_fields = dict(filter(can_update, tag_type_fields.items()))
+        
+        accepted_type_fields = dict(filter(can_update, tag_type_fields.items()))
+        rejected_keys = [ k for k in tag_type_fields if k not in accepted_type_fields ]
+        if rejected_keys:
+            error="Cannot update TagType column(s) %r"%rejected_keys
+            if 'roles' in rejected_keys or 'role_ids' in rejected_keys:
+                error += " see AddRoleToTagType DeleteRoleFromTagType"
+            raise PLCInvalidArgument, error
 
         tag_types = TagTypes(self.api, [tag_type_id_or_name])
         if not tag_types:
             raise PLCInvalidArgument, "No such tag type"
         tag_type = tag_types[0]
 
-        tag_type.update(tag_type_fields)
+        tag_type.update(accepted_type_fields)
         tag_type.sync()
         self.object_ids = [tag_type['tag_type_id']]