URL link to open Service Desk message

Hi Experts,

I have an email that is sent via a custom action from a service desk ticket.

In this email I attach a document created via SMARTFORM. This document contains a URL which should (when clicked) open the ticket in a browser.

I have all I need (ticket ID, host, port number etc.) but I don't know how to construct the full URL. Anybody could indicate how to do this?

Many thanks,

Brodo