Newbie question: Istio 1.3.4 response header with dynamic timestamp in VirtualService


I’m geting started with Istio and I couldn’t find any resource about how can I add a dynamic vale in HeaderOperations. I would like to add a Last-Modified with the current date timestamp in the response header. Another option would be use the “Date” header as the value for Last-Modified.

Any tip or guidance would be very appreciated