How to build a widget with external ports

[frankbenoit]

I want to build a widget that is rectangular and does have square ports attached to it.

So I create a GNode and GPort instances.

When I add the ports as child of the node, the node expands size to have the ports inside its borders.
How can I make the ports to be outside the node, but anchored to it?
Do I need to have changes in the client?

I thought about having an "invisible" parent node to have the ports inside it. But I could not figure out how to make it invisible. And still the inner node seems to stretch out to the ports.