Method set_value

opcua/common/node.py:195–217

Set value of a node. Only variables(properties) have values. An exception will be generated for other node types. value argument is either: * a python built-in type, converted to opc-ua optionnaly using the variantype argument. * a ua.Variant, variant

(self, value, varianttype=None)

        return res.Value.Value

    def set_value(self, value, varianttype=None):
        """
        Set value of a node. Only variables(properties) have values.
        An exception will be generated for other node types.
        value argument is either:
        * a python built-in type, converted to opc-ua
        optionnaly using the variantype argument.
        * a ua.Variant, varianttype is then ignored
        * a ua.DataValue, you then have full control over data send to server
        WARNING: On server side, ref to object is directly saved in our UA db, if this is a mutable object
        and you modfy it afterward, then the object in db will be modified without any
        data change event generated
        """
        datavalue = None
        if isinstance(value, ua.DataValue):
            datavalue = value
        elif isinstance(value, ua.Variant):
            datavalue = ua.DataValue(value)
            datavalue.SourceTimestamp = datetime.utcnow()
        else:
            datavalue = ua.DataValue(ua.Variant(value, varianttype))
            datavalue.SourceTimestamp = datetime.utcnow()
        self.set_attribute(ua.AttributeIds.Value, datavalue)

    set_data_value = set_value