Add default icon to node

Is it possible to add default icon to Node?

$(go.Picture, { source: “icons/example.png”, background: “gray”, width: 50, height: 50 })

In above example if example.png is not available at icons folder then I want the node to show a default icon.

In my current code I am using http.get() method to check whether icon exist in path or not. Looks like this is causing some performance issue in loading my data because I have more than 1000 nodes to be checked whether icon exist or not.

Perhaps you could make use of this event handler: Picture | GoJS API