gistfile1.txt

func ensureDesiredUpgradeVersion(_ context.Context, clusterVersionLister configv1listers.ClusterVersionLister) (string, error){
	config, err := clusterVersionLister.Get("version")
	if err != nil {
		return "", err
	}

	desiredUpdate := config.Spec.DesiredUpdate
	// Wait for CVO to populate desired status if empty
	//TODO ensure desired update is expected to be always populated
	if desiredUpdate == nil {
		return "", fmt.Errorf("cluster version desired update is not yet initialized")
	}

	desiredVersion := desiredUpdate.Version
	desiredSemver, err := semver.Parse(desiredVersion)
	if err != nil {
		return "", err
	}

	// Wait for CVO to initialize new history if empty
	if len(config.Status.History) == 0 {
		return "", fmt.Errorf("cluster version history is not yet intialized" )
	}
	currentVersion := config.Status.History[0].Version
	currentSemver, err := semver.Parse(currentVersion)
	if err != nil {
		return "", err
	}

	// verify minor upgrade is desired otherwise our job is done for now.
	if ! isMinorUpgrade(currentSemver,desiredSemver) {
		klog.Infof("Cluster upgrade backup controller only takes backups during minor version upgrades, current: %s, desired: %s", currentVersion, desiredVersion)
		return "", fmt.Errorf("%s",metav1.StatusReasonNotFound)
	}
	return desiredVersion, nil
}


func isMinorUpgrade(currentVersion, desiredVersion semver.Version) bool {
	if currentVersion.Minor + 1 == desiredVersion.Minor {
		return true
	}
	return false