Vaadin 8 + Keycloak

I have a small Vaadin app that I want to secure with Keycloak. This isn’t a Springboot app or something and I also don’t use Spring Security, documentation is therefor scarce.
I did managed to secure a small Springboot app though and I thought I could sort of copy/paste this to Vaadin but alas…
Does anyone here have any experience with this? It’s rather shocking that there is absolutely no documentation on this.

The main issue i’m stuck on is that my Tomcat log tells me this;

"Cannot configure an authenticator for method KEYCLOAK"

So in my web.xml I defined




When I change KEYCLOAK to BASIC, it prompts for logincredentials but not through Keycloak, but instead with a small popup that you normally see when auth-method is set to BASIC. Also, the credentials I enter and should work, don’t.

And that’s where it fails apparently.
Help :frowning:

I am getting the same error. Were you able to solve this error?

No solution found yet…

I’m also not 100% sure this is the way to go.

Surely people must have used Keycloak and Vaadin together?