Filter-based authentication without Spring

Hi, I’m just starting my journey with Vaadin and I’m pretty much impressed on how much straightforward it is in comparison with GWT. So first of all I’d like to say that I appreciate the work the team made to get the framework to work that smooth!

Now, getting to the point of my question. I’m looking for a way to properly implement filter-based authentication in latest Vaadin. So far I was able to find either outdated solutions targeted to Vaadin 8, 7 and earlier, or examples based on Spring framework which I don’t plan to use. I’m worried that trying to re-invent the wheel without deep understanding of Vaadin logics would result in painful and unrewarding experience, so I’d be grateful for any help here.

Also posed this at [SO]
(https://stackoverflow.com/questions/56085570/filter-based-user-authentication-for-vaadin-10-without-spring)