How to create diagram inside diagram

Hello, I am using GoJS with the angular framework.

I want to create a diagram that contains another diagram as a node.
My purpose finally is when I will click on the “node”, the other diagram will be shown.
How can it be done?

Thank you.

Where do you want the second diagram to appear?

If you want it to appear in a small area of the first diagram, use Groups to hold those subgraphs.
https://gojs.net/latest/intro/groups.html
https://gojs.net/latest/intro/subgraphs.html
Note that the subgraph in a group cannot be independently scaled (zoomed) or positioned (scrolled) or clipped.

If you want it to show in a different HTML DIV with a different Diagram, just do it using a separate GraphLinksModel.