Confusion about error codes|OPC UA Standard|Forum|OPC Foundation

Hi all

Trying to implement the ISA95 Jobcontrol we are running in some problems: how to deal with method results?

The specificaiton of the method service set (https://reference.opcfoundatio...../docs/5.12) defines a "common" status code Bad_InvalidArgument for "brokes a constraint" -> most of them could only be checked/defined by an application. So this leads to the assumption, that Bad_InvalidArgument could used as service and as operation level result.

But the table 176 in https://reference.opcfoundatio.....ocs/7.38.2 restricts Bad_InvalidArgument to the communication stack, so an application is not allowed to use this. However, the introduction mentions that all status codes from Table 176 may also be used for the operation level (i.e., the application).

To extend the confusion:

- https://reference.opcfoundatio...../docs/5.12 defines in the table 59 "Bad_InvalidArgument" with an example for out of range -> shouldn't be Bad_OutOfRange status code used instead? Or does the application return Bad_OutOfRange and the communication stack inserts this in the inputAgrumentResults

- https://reference.opcfoundatio.....1/docs/6.7 uses mostly service level status codes for application specific topics - Bad_InvalidArgument is mentioned. What should be used if a method call is made on the wrong state (e.g. Start in state Running)?

- https://reference.opcfoundatio.....200/docs/B uses Bad_InvalidArgument in parallel with ISA95 "Invalid Job Order Status" or Bad_ArgumentMissing with "Unknown Job Order ID" without any explenations. When should what be used?

- Our developers reported, that at least the open source .NET reference implementation doesn't allow the application to set/define inputArgumentResults of the method service response (what is required for Bad_InvalidArgument by definition). So this is either a bug in the stack or this status code cannot be used by the application/operation level as documented in various places (e.g. packml, isa95).

Specific questions/problems: what should be reported by the server if

- a method was called on the wrong state for a state machine? Bad_InvalidState or Bad_MethodInvalid?

- at least one from the application defined mandatory element is missing (e.g. ISA95JobOrderDataType.StartTime)? Bad_ArgumentsMissing?

- at least one provided argument in a structure is out of range, supported by the application (e.g. ISA95JobOrderDataType.JobOrderParamters[RunsPlanned])? Bad_OutOfRange?

- at least one provided argument in a structure has wrong type (e.g. ISA95JobOrderDataType.JobOrderParamters[RunsPlanned] is defined as UInt32, but client provides string)? Bad_TypeMismatch?

Best regards

Patrick