Using KCP-like API server to re-use controller pattern

[invidian]

Not sure if that's the right place to discuss, please redirect if we have a better one.

We talked about possibility of using KCP-like API server as a runtime, so then configuration management of SO can be done using tooling familiar for people like controller-runtime, kube-builder, Helm etc.

It seems that concept of extension-api-server is also worth mentioning for that. Our imaginary extension API server could then read e.g. /proc on the fly and report resources to kubectl. IIRC extension API servers must deal with the storage on their own.

Example of extension API server: https://github.com/kubernetes/sample-apiserver

If we use that approach, we should also consider what roles controller-manager plays and if we are going to miss some functionality from it, e.g. garbage collection?

EDIT: I implemented some quick PoC, available here: https://github.com/invidian/koss.

[andrewrynhard]

Thanks @invidian . Very interesting idea on using the extension-api-server!

[invidian]

Added PoC link to the OP.