Change:
return r, err } if len(r.APIResources) == 0 { <del> return r, fmt.Errorf("Got empty response for: %v", groupVersion) </del> <ins> return r, &emptyResponseError{gv: groupVersion} </ins> } return r, nil }

Discussion:
I think this got stale and closed because it was posted on but is still very relevant: The created by memory.NewMemCacheClient(...) returns an error when calling ServerResourcesForGroupVersion if the APIResources list returned is empty, as seen here: Our particular case came up due to the API group being registered with the API server, but having no resources. If using like to discover with zero current resources there should not be an error returned. Do a discovery with a against a Kubernetes cluster that has at least one with zero resources. The condition on the server that triggers the described issue can be expressed as e.g.: I would be good to get to know the reasoning behind the emptiness check in the , maybe there is good reason for it. <detailsClient Version: v1.20.15 Server Version: v1.22.8-gke.202 </details<detailsGoogle Cloud (GKE) </detailsNo response No response No response No response
/sig api-machinery
/cc /triage accepted
The Kubernetes project currently lacks enough contributors to adequately respond to all issues and PRs. This bot triages issues and PRs according to the following rules: After 90d of inactivity, is applied After 30d of inactivity since was applied, is applied After 30d of inactivity since was applied, the issue is closed You can: Mark this issue or PR as fresh with Mark this issue or PR as rotten with Close this issue or PR with Offer to help out with [Issue Triage][1] Please send feedback to sig-contributor-experience at . /lifecycle stale [1]:
/remove-lifecycle stale
The Kubernetes project currently lacks enough contributors to adequately respond to all issues and PRs. This bot triages issues and PRs according to the following rules: After 90d of inactivity, is applied After 30d of inactivity since was applied, is applied After 30d of inactivity since was applied, the issue is closed You can: Mark this issue or PR as fresh with Mark this issue or PR as rotten with Close this issue or PR with Offer to help out with [Issue Triage][1] Please send feedback to sig-contributor-experience at .

/lifecycle stale [1]:
Reviving this issue based on This behavior has become quite annoying for the custom/external metrics aggregated APIs since after , client-go is now producing a very spammy error log when an aggregated API is found without resource. This is a very common scenario with the metric APIs since metrics are dynamically registered as Resources to the aggregated APIs so on startup the aggregated apiserver may not expose any resource and that's completely normal. It is even more common for implementations of these APIs that register metric Resources from CRDs as CRs tend to be created later than APIServices and the aggregated apiserver. I can see a few path forward to improve the situation for us: the error if we consider that having no resources exposed by an aggregated API is acceptable the verbosity of the log to just show it in debugging scenarios somehow update to defer registration until we have at least one Metric resource. could you perhaps share your insight on that one please? /remove-lifecycle stale
Hello folks! Any update on this topic? The message is really spammy
Removing triage accepted manually since there was no update on this for more than 6 months. /remove-triage accepted
For context, I traced it back and check has been considered an error since the first iteration of the in-memory discovery client in : It is unexpected for a built-in or CRD groupversion to have no resources, but for aggregated-apiservice I can see it being possible that the object is created and set up for discovery before the aggregated-apiservice is ready.
I think this is which introduces (but maybe I'm wrong). There is also in that repo about the same issue after upgrading the kube-client pkg. in custom-metrics repo be correct from Kubernetes pov? IMO we need to find a solution soon or the amount of noise will increase once people bump their deps and tooling (, kubectl is affected, and any tool which uses kube-client is affected)
/triage accepted