Given a JSON-RPC method in:  [interface].[function] notation, returns a tuple of the interface
    name and function.

    For example, unpack_method("MyService.LoadUser") would return: ("MyService", "LoadUser")

    :Parameters:
      method
        String method name

def unpack_method(method):
    """
    Given a JSON-RPC method in:  [interface].[function] notation, returns a tuple of the interface
    name and function.

    For example, unpack_method("MyService.LoadUser") would return: ("MyService", "LoadUser")

    :Parameters:
      method
        String method name
    """
    pos = method.find(".")
    if pos == -1:
        raise RpcException(ERR_METHOD_NOT_FOUND, "Method not found: %s" % method)

    iface_name = method[:pos]
    func_name  = method[pos+1:]
    return iface_name, func_name