"k8s.io/kubernetes/cmd/kubeadm/app/util/patches"
)

const (
	unableToDecodeCoreDNS = "unable to decode CoreDNS"
	coreDNSReplicas       = 2
)

// DeployedDNSAddon returns the image tag of the DNS addon currently deployed
func DeployedDNSAddon(client clientset.Interface) (string, error) {
	deploymentsClient := client.AppsV1().Deployments(metav1.NamespaceSystem)

			client := newMockClientForTest(t, 1, tt.deploymentSize, tt.image, "", "")

			version, err := DeployedDNSAddon(client)
			if (err != nil) != tt.wantErr {
				t.Errorf("DeployedDNSAddon() error = %v, wantErr %v", err, tt.wantErr)
			}
			if version != tt.wantVersion {
				t.Errorf("DeployedDNSAddon() for image %q returned %q, want %q", tt.image, version, tt.wantVersion)
			}
		})
	}
}

	etcdVersions, err := versionGetterImpl.ComponentVersions(kubeadmconstants.Etcd)
	if err != nil {
		return upgrades, err
	}
	isExternalEtcd := len(etcdVersions) == 0

	dnsVersion, err := dns.DeployedDNSAddon(client)
	if err != nil {
		return nil, err
	}

	// Construct a descriptor for the current state of the world
	beforeState := ClusterState{
		KubeVersion:                   clusterVersionStr,