add resizing operation

[sevagol]

added a comparison of pvc size with the existing one, and deletion in case of discrepancy. Should a new statefulset be created automatically after this?

[kvaps]

Please add this functionaity before this function

etcd-operator/internal/controller/etcdcluster_controller.go

Line 136 in 010228b

if err := factory.CreateOrUpdateStatefulSet(ctx, cluster, r.Client); err != nil {

It should be separate function eg.:

if isStatefulSetDeletionRequired; {
    if err := factory.DeleteStatefulSet(ctx, cluster, r.Client); err != nil {
    	return err
    }
}

[kvaps]

please use native Kubernetes method for comparing sizes instead of reflect

if desiredStorage.Cmp(currentStorage) != 0 {
    // desiredStorage different, than currentStorage
}

[kvaps]

you have to compare storage from specific statefulSet.Spec.VolumeClaimTemplate, not pvc

[makhov]

Do I understand it properly: with this PR we just update the StatefulSet without actual resizing of the PVCs?

Since the PVCs are already created they won't be changed even if the volumeClaimTemplates are changed. Here is the doc on how to resize the PVC:
https://kubernetes.io/blog/2018/07/12/resizing-persistent-volumes-using-kubernetes/

[kvaps]

Correct, the resizing of PVCs will probably implemented in separate PR

[kvaps]

closed if favor #254