uamethod unable to recognize Enumerator type

[danmoser]

Dear,
I noticed that @uamethod doesn't recognize the Enumerator type as an argument. See the example server below. When running it, this is what I get:

method call with parameter:  1 <class 'int'>

Is this the expected behavior?

UaExpert identifies the argument type correctly:

import logging
import asyncio

from asyncua import ua, Server, uamethod
from asyncua.common.structures104 import new_enum

logging.basicConfig(level=logging.INFO)
_logger = logging.getLogger('asyncua')


@uamethod
def multiply(parent, x):
    print("method call with parameter: ", x, type(x))
    return


async def main():
    # setup our server
    server = Server()
    await server.init()
    server.set_endpoint('opc.tcp://0.0.0.0:4841/freeopcua/server/')

    # setup our own namespace, not really necessary but should as spec
    uri = 'http://examples.freeopcua.github.io'
    idx = await server.register_namespace(uri)

    enode = await new_enum(server, ua.NodeId('myEnumDef', idx), 
        ua.QualifiedName('myEnum', idx), [
        "titi",
        "toto",
        "tutu",
    ])

    custom_objs = await server.load_data_type_definitions()
    print("Custom objects on server")
    for name, obj in custom_objs.items():
        print("    ", obj)

    await server.nodes.objects.add_variable(idx, "myEnumInstance", ua.myEnum.toto, 
        datatype=enode.nodeid)

    inargx = ua.Argument()
    inargx.Name = "x"
    inargx.DataType = ua.NodeId('myEnumDef', idx)
    inargx.ValueRank = -1
    inargx.ArrayDimensions = []
    inargx.Description = ua.LocalizedText("Enum as Argument")

    await server.nodes.objects.add_method(idx, "myMethod", multiply, [inargx])

    async with server:
        while True:
            await asyncio.sleep(1)


if __name__ == '__main__':
    asyncio.run(main())

[schroeder-]

This issue is tricky. The enum gets converted to an Int32 and for the encoding layer there is no way to know it is enum. So either we check the values before passing them to the method and convert them. Or we expand the @uamethod decorator to convert some arguments.

The issue also exists the otherway, if you recive a enum as methodcall result.

[schroeder-]

A after a bit of digging i would recommend to cast the parameter like this:

@uamethod
def multiply(parent, x):
    x = ua.myEnum(x)
    print("method call with parameter: ", x, type(x))
    return

[danmoser]

That's a very convenient function. Thanks @schroeder- !