Is it possible to get the Portal base URL (like http://www.thisismyportal.com) from a Portlet using Portlet 2.0 API?
Right now I'm planning to manually build it concatenating PorletRequest.getServerName(), PortletRequest.getServerPort() and PortletRequest.getContextPath(); but it seems kind of clumsy (and there's no PortletRequest.getProtocol())
We had those configuration properties in Resource Environment Provider for the purpose of generating external URLs for sending them in emails. It was specific solution and it wasn't a problem for us as we had other properties stored there as well so we knew it will be available at runtime. I don't know if that suits your needs. It depends on your scenario. Also, we used https only during login, so we always generated http URLs.
Hope this helps.