kubeadm: switch from ExponentialBackoff() to PollUntilContextTimeout()

Switch to PollUntilContextTimeout() everywhere to allow
usage of the exposed timeouts in the kubeadm API. Exponential backoff
options are more difficult to expose in this regard and a bit too
detailed for the common user - i.e. have "steps", "factor" and so on.

cmd/kubeadm/app/constants/constants.go

@@ -28,7 +28,6 @@ import (
 
 	v1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/util/version"
-	"k8s.io/apimachinery/pkg/util/wait"
 	apimachineryversion "k8s.io/apimachinery/pkg/version"
 	componentversion "k8s.io/component-base/version"
 	netutils "k8s.io/utils/net"
@@ -495,15 +494,6 @@ var (
 	// the bootstrap tokens to access the kubeadm-certs Secret during the join of a new control-plane
 	KubeadmCertsClusterRoleName = fmt.Sprintf("kubeadm:%s", KubeadmCertsSecret)
 
-	// StaticPodMirroringDefaultRetry is used a backoff strategy for
-	// waiting for static pods to be mirrored to the apiserver.
-	StaticPodMirroringDefaultRetry = wait.Backoff{
-		Steps:    30,
-		Duration: 1 * time.Second,
-		Factor:   1.0,
-		Jitter:   0.1,
-	}
-
 	// defaultKubernetesPlaceholderVersion is a placeholder version in case the component-base
 	// version was not populated during build.
 	defaultKubernetesPlaceholderVersion = version.MustParseSemantic("v1.0.0-placeholder-version")

cmd/kubeadm/app/util/config/cluster.go

@@ -22,6 +22,7 @@ import (
 	"fmt"
 	"path/filepath"
 	"strings"
+	"time"
 
 	"github.com/pkg/errors"
 
@@ -195,29 +196,33 @@ func getNodeNameFromKubeletConfig(fileName string) (string, error) {
 }
 
 func getAPIEndpoint(client clientset.Interface, nodeName string, apiEndpoint *kubeadmapi.APIEndpoint) error {
-	return getAPIEndpointWithBackoff(client, nodeName, apiEndpoint, constants.StaticPodMirroringDefaultRetry)
+	return getAPIEndpointWithRetry(client, nodeName, apiEndpoint,
+		constants.StaticPodMirroringRetryInterval, constants.StaticPodMirroringTimeout)
 }
 
-func getAPIEndpointWithBackoff(client clientset.Interface, nodeName string, apiEndpoint *kubeadmapi.APIEndpoint, backoff wait.Backoff) error {
+func getAPIEndpointWithRetry(client clientset.Interface, nodeName string, apiEndpoint *kubeadmapi.APIEndpoint,
+	interval, timeout time.Duration) error {
 	var err error
 	var errs []error
 
-	if err = getAPIEndpointFromPodAnnotation(client, nodeName, apiEndpoint, backoff); err == nil {
+	if err = getAPIEndpointFromPodAnnotation(client, nodeName, apiEndpoint, interval, timeout); err == nil {
 		return nil
 	}
 	errs = append(errs, errors.WithMessagef(err, "could not retrieve API endpoints for node %q using pod annotations", nodeName))
 	return errorsutil.NewAggregate(errs)
 }
 
-func getAPIEndpointFromPodAnnotation(client clientset.Interface, nodeName string, apiEndpoint *kubeadmapi.APIEndpoint, backoff wait.Backoff) error {
+func getAPIEndpointFromPodAnnotation(client clientset.Interface, nodeName string, apiEndpoint *kubeadmapi.APIEndpoint,
+	interval, timeout time.Duration) error {
 	var rawAPIEndpoint string
 	var lastErr error
 	// Let's tolerate some unexpected transient failures from the API server or load balancers. Also, if
 	// static pods were not yet mirrored into the API server we want to wait for this propagation.
-	err := wait.ExponentialBackoff(backoff, func() (bool, error) {
-		rawAPIEndpoint, lastErr = getRawAPIEndpointFromPodAnnotationWithoutRetry(client, nodeName)
-		return lastErr == nil, nil
-	})
+	err := wait.PollUntilContextTimeout(context.Background(), interval, timeout, true,
+		func(ctx context.Context) (bool, error) {
+			rawAPIEndpoint, lastErr = getRawAPIEndpointFromPodAnnotationWithoutRetry(ctx, client, nodeName)
+			return lastErr == nil, nil
+		})
 	if err != nil {
 		return err
 	}
@@ -229,9 +234,9 @@ func getAPIEndpointFromPodAnnotation(client clientset.Interface, nodeName string
 	return nil
 }
 
-func getRawAPIEndpointFromPodAnnotationWithoutRetry(client clientset.Interface, nodeName string) (string, error) {
+func getRawAPIEndpointFromPodAnnotationWithoutRetry(ctx context.Context, client clientset.Interface, nodeName string) (string, error) {
 	podList, err := client.CoreV1().Pods(metav1.NamespaceSystem).List(
-		context.TODO(),
+		ctx,
 		metav1.ListOptions{
 			FieldSelector: fmt.Sprintf("spec.nodeName=%s", nodeName),
 			LabelSelector: fmt.Sprintf("component=%s,tier=%s", constants.KubeAPIServer, constants.ControlPlaneTier),

cmd/kubeadm/app/util/config/cluster_test.go

@@ -25,14 +25,14 @@ import (
 	"strconv"
 	"strings"
 	"testing"
+	"time"
 
 	"github.com/pkg/errors"
 
 	v1 "k8s.io/api/core/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
-	"k8s.io/apimachinery/pkg/util/wait"
 	clientsetfake "k8s.io/client-go/kubernetes/fake"
 	clienttesting "k8s.io/client-go/testing"
 
@@ -461,7 +461,8 @@ func TestGetAPIEndpointWithBackoff(t *testing.T) {
 				}
 			}
 			apiEndpoint := kubeadmapi.APIEndpoint{}
-			err := getAPIEndpointWithBackoff(client, rt.nodeName, &apiEndpoint, wait.Backoff{Duration: 0, Jitter: 0, Steps: 1})
+			err := getAPIEndpointWithRetry(client, rt.nodeName, &apiEndpoint,
+				time.Millisecond*10, time.Millisecond*100)
 			if err != nil && !rt.expectedErr {
 				t.Errorf("got error %q; was expecting no errors", err)
 				return
@@ -718,7 +719,8 @@ func TestGetAPIEndpointFromPodAnnotation(t *testing.T) {
 				rt.clientSetup(client)
 			}
 			apiEndpoint := kubeadmapi.APIEndpoint{}
-			err := getAPIEndpointFromPodAnnotation(client, rt.nodeName, &apiEndpoint, wait.Backoff{Duration: 0, Jitter: 0, Steps: 1})
+			err := getAPIEndpointFromPodAnnotation(client, rt.nodeName, &apiEndpoint,
+				time.Millisecond*10, time.Millisecond*100)
 			if err != nil && !rt.expectedErr {
 				t.Errorf("got error %v, but wasn't expecting any error", err)
 				return
@@ -832,7 +834,7 @@ func TestGetRawAPIEndpointFromPodAnnotationWithoutRetry(t *testing.T) {
 			if rt.clientSetup != nil {
 				rt.clientSetup(client)
 			}
-			endpoint, err := getRawAPIEndpointFromPodAnnotationWithoutRetry(client, rt.nodeName)
+			endpoint, err := getRawAPIEndpointFromPodAnnotationWithoutRetry(context.Background(), client, rt.nodeName)
 			if err != nil && !rt.expectedErr {
 				t.Errorf("got error %v, but wasn't expecting any error", err)
 				return