Skip already removed APIs

[phandox]

Hi,

I am trying to find a way for kubent to skip checking already removed APIs (for example - PodSecurityPolicy on 1.25+ K8S clusters). From the the debug output, I see that it's trying to fetch the APIs, even when the cluster is already on 1.26.

11:01AM DBG Retrieving: podsecuritypolicies.v1beta1.policy
11:01AM DBG Failed to retrieve: policy/v1beta1, Resource=podsecuritypolicies: the server could not find the requested resource

The reason for this, is that I use GKE and Recommender API will detect clients using deprecated APIs. It will then stop auto-upgrading clusters until no calls to removed or deprecated APIs are made for at least 30 days. Having a flag available, which would turn off calling these already removed API would be great help for me.

If you think it would be useful, I can try to make a PR if we work out some specification how it could work.

Thanks!

[stepanstipl]

This is a potentially interesting feature, currently not supported.

The implementation should not be too difficult - we would have to introduce new piece of info that we currently don't have, about all the resource/versions and when they stopped being supported. However, it's another bit that's fairly expensive to maintain. Or implement some discovery phase of supported GVKs and only query those, probably better, but more work initially.

In anycase, I see why this would make sense and we will consider implementing it in the future. Thanks for raising this 👍

[madAndroid]

Similar to this use case, it would be useful to be able to exclude rulesets from the different ones being checked .. we're on 1.24.x, looking to upgrade to 1.25.x, and we're getting failures for 1.22 resources - presumably for legacy manifests still in place on in etcd, even though the resources have been upgraded to newer versions already.
Being able to exclude rulesets would allow us to surface only requirements for specific upgrades