I have a basic Ruby on Rails app up on Kube but with no authentication and no SSL certificate. What should I learn next to add these things? How did you learn these things?
This will help you learn the ingress pattern. After that, I would suggest exploring ways to tack a sidecar on (log aggregator, etc) - my impression is you are just looking for things to learn, I wouldn't normally suggest doing this just to do it.
Alternatively, you could try exploring putting grafana/prometheus in, though this can be a big bite for someone learning, so I would recommend learning/comprehending sidecars/ingress, etc as they are some of the building blocks for k8s.
Edit: I see there's another comment for traefik for ingress - that's fine too, it's the concept that matters, not your particular choice. If you have a lot of trouble implementing one, try the other one, things you learn in your journey will help quite a bit.
Cant edit since on mobile