Merge pull request #51008 from kubernetes/revert-50789-fix-scheme

Revert "Don't register the kubeletconfig group with the default Scheme"

cmd/kubelet/app/options/BUILD

@@ -12,10 +12,11 @@ go_library(
         "options.go",
     ],
     deps = [
+        "//pkg/api:go_default_library",
         "//pkg/apis/componentconfig:go_default_library",
         "//pkg/features:go_default_library",
         "//pkg/kubelet/apis/kubeletconfig:go_default_library",
-        "//pkg/kubelet/apis/kubeletconfig/scheme:go_default_library",
+        "//pkg/kubelet/apis/kubeletconfig/install:go_default_library",
         "//pkg/kubelet/apis/kubeletconfig/v1alpha1:go_default_library",
         "//pkg/kubelet/apis/kubeletconfig/validation:go_default_library",
         "//pkg/util/taints:go_default_library",

cmd/kubelet/app/options/options.go

@@ -25,12 +25,14 @@ import (
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/apiserver/pkg/util/flag"
 	utilflag "k8s.io/apiserver/pkg/util/flag"
+	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/apis/componentconfig"
 	"k8s.io/kubernetes/pkg/features"
 	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig"
-	kubeletscheme "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/scheme"
-	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/v1alpha1"
 	kubeletconfigvalidation "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/validation"
+	// Need to make sure the kubeletconfig api is installed so defaulting funcs work
+	_ "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/install"
+	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/v1alpha1"
 	utiltaints "k8s.io/kubernetes/pkg/util/taints"
 
 	"github.com/spf13/pflag"
@@ -140,14 +142,10 @@ func ValidateKubeletFlags(f *KubeletFlags) error {
 
 // NewKubeletConfiguration will create a new KubeletConfiguration with default values
 func NewKubeletConfiguration() (*kubeletconfig.KubeletConfiguration, error) {
-	scheme, _, err := kubeletscheme.NewSchemeAndCodecs()
-	if err != nil {
-		return nil, err
-	}
 	versioned := &v1alpha1.KubeletConfiguration{}
-	scheme.Default(versioned)
+	api.Scheme.Default(versioned)
 	config := &kubeletconfig.KubeletConfiguration{}
-	if err := scheme.Convert(versioned, config, nil); err != nil {
+	if err := api.Scheme.Convert(versioned, config, nil); err != nil {
 		return nil, err
 	}
 	return config, nil

cmd/kubelet/app/server.go

@@ -756,8 +756,7 @@ func parseResourceList(m kubeletconfiginternal.ConfigurationMap) (v1.ResourceLis
 }
 
 // BootstrapKubeletConfigController constructs and bootstrap a configuration controller
-func BootstrapKubeletConfigController(
+func BootstrapKubeletConfigController(flags *options.KubeletFlags,
-	flags *options.KubeletFlags,
 	defaultConfig *kubeletconfiginternal.KubeletConfiguration) (*kubeletconfiginternal.KubeletConfiguration, *kubeletconfig.Controller, error) {
 	var err error
 	// Alpha Dynamic Configuration Implementation; this section only loads config from disk, it does not contact the API server
@@ -778,10 +777,7 @@ func BootstrapKubeletConfigController(
 	}
 
 	// get the latest KubeletConfiguration checkpoint from disk, or load the init or default config if no valid checkpoints exist
-	kubeletConfigController, err := kubeletconfig.NewController(initConfigDir, dynamicConfigDir, defaultConfig)
+	kubeletConfigController := kubeletconfig.NewController(initConfigDir, dynamicConfigDir, defaultConfig)
-	if err != nil {
-		return nil, nil, fmt.Errorf("failed to construct controller, error: %v", err)
-	}
 	kubeletConfig, err := kubeletConfigController.Bootstrap()
 	if err != nil {
 		return nil, nil, fmt.Errorf("failed to determine a valid configuration, error: %v", err)

cmd/kubelet/kubelet.go

@@ -89,10 +89,7 @@ func main() {
 	}
 
 	// construct a KubeletServer from kubeletFlags and kubeletConfig
-	kubeletServer := &options.KubeletServer{
+	kubeletServer := &options.KubeletServer{KubeletFlags: *kubeletFlags, KubeletConfiguration: *kubeletConfig}
-		KubeletFlags:         *kubeletFlags,
-		KubeletConfiguration: *kubeletConfig,
-	}
 
 	// use kubeletServer to construct the default KubeletDeps
 	kubeletDeps, err := app.UnsecuredDependencies(kubeletServer)

pkg/kubelet/apis/kubeletconfig/BUILD

@@ -36,7 +36,7 @@ filegroup(
     name = "all-srcs",
     srcs = [
         ":package-srcs",
-        "//pkg/kubelet/apis/kubeletconfig/scheme:all-srcs",
+        "//pkg/kubelet/apis/kubeletconfig/install:all-srcs",
         "//pkg/kubelet/apis/kubeletconfig/v1alpha1:all-srcs",
         "//pkg/kubelet/apis/kubeletconfig/validation:all-srcs",
     ],

pkg/kubelet/apis/kubeletconfig/install/BUILD

@@ -1,14 +1,23 @@
-load("@io_bazel_rules_go//go:def.bzl", "go_library")
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+load(
+    "@io_bazel_rules_go//go:def.bzl",
+    "go_library",
+)
 
 go_library(
     name = "go_default_library",
-    srcs = ["scheme.go"],
+    srcs = ["install.go"],
-    visibility = ["//visibility:public"],
+    tags = ["automanaged"],
     deps = [
+        "//pkg/api:go_default_library",
         "//pkg/kubelet/apis/kubeletconfig:go_default_library",
         "//pkg/kubelet/apis/kubeletconfig/v1alpha1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apimachinery/announced:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/apimachinery/registered:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",
-        "//vendor/k8s.io/apimachinery/pkg/runtime/serializer:go_default_library",
     ],
 )
 
@@ -23,5 +32,4 @@ filegroup(
     name = "all-srcs",
     srcs = [":package-srcs"],
     tags = ["automanaged"],
-    visibility = ["//visibility:public"],
 )

pkg/kubelet/apis/kubeletconfig/install/install.go

@@ -0,0 +1,49 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package install installs the experimental API group, making it available as
+// an option to all of the API encoding/decoding machinery.
+package install
+
+import (
+	"k8s.io/apimachinery/pkg/apimachinery/announced"
+	"k8s.io/apimachinery/pkg/apimachinery/registered"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig"
+	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/v1alpha1"
+)
+
+func init() {
+	// TODO(mtaufen): probably want to create a kubelet scheme rather than reusing the api scheme, but need to ask lavalamp
+	Install(api.GroupFactoryRegistry, api.Registry, api.Scheme)
+}
+
+// Install registers the API group and adds types to a scheme
+func Install(groupFactoryRegistry announced.APIGroupFactoryRegistry, registry *registered.APIRegistrationManager, scheme *runtime.Scheme) {
+	if err := announced.NewGroupMetaFactory(
+		&announced.GroupMetaFactoryArgs{
+			GroupName:                  kubeletconfig.GroupName,
+			VersionPreferenceOrder:     []string{v1alpha1.SchemeGroupVersion.Version},
+			AddInternalObjectsToScheme: kubeletconfig.AddToScheme,
+		},
+		announced.VersionToSchemeFunc{
+			v1alpha1.SchemeGroupVersion.Version: v1alpha1.AddToScheme,
+		},
+	).Announce(groupFactoryRegistry).RegisterAndEnable(registry, scheme); err != nil {
+		panic(err)
+	}
+}

pkg/kubelet/apis/kubeletconfig/scheme/scheme.go

@@ -1,40 +0,0 @@
-/*
-Copyright 2017 The Kubernetes Authors.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package scheme
-
-import (
-	"k8s.io/apimachinery/pkg/runtime"
-	"k8s.io/apimachinery/pkg/runtime/serializer"
-	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig"
-	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/v1alpha1"
-)
-
-// Utility functions for the Kubelet's kubeletconfig API group
-
-// NewSchemeAndCodecs is a utility funciton that returns a Scheme and CodecFactory
-// that understand the types in the kubeletconfig API group.
-func NewSchemeAndCodecs() (*runtime.Scheme, *serializer.CodecFactory, error) {
-	scheme := runtime.NewScheme()
-	if err := kubeletconfig.AddToScheme(scheme); err != nil {
-		return nil, nil, err
-	}
-	if err := v1alpha1.AddToScheme(scheme); err != nil {
-		return nil, nil, err
-	}
-	codecs := serializer.NewCodecFactory(scheme)
-	return scheme, &codecs, nil
-}

pkg/kubelet/kubeletconfig/checkpoint/BUILD

@@ -15,8 +15,8 @@ go_test(
     ],
     library = ":go_default_library",
     deps = [
+        "//pkg/api:go_default_library",
         "//pkg/kubelet/apis/kubeletconfig:go_default_library",
-        "//pkg/kubelet/apis/kubeletconfig/scheme:go_default_library",
         "//pkg/kubelet/apis/kubeletconfig/v1alpha1:go_default_library",
         "//pkg/kubelet/kubeletconfig/util/codec:go_default_library",
         "//pkg/kubelet/kubeletconfig/util/test:go_default_library",
@@ -40,14 +40,12 @@ go_library(
     deps = [
         "//pkg/api:go_default_library",
         "//pkg/kubelet/apis/kubeletconfig:go_default_library",
-        "//pkg/kubelet/apis/kubeletconfig/scheme:go_default_library",
         "//pkg/kubelet/kubeletconfig/util/codec:go_default_library",
         "//pkg/kubelet/kubeletconfig/util/log:go_default_library",
         "//vendor/k8s.io/api/core/v1:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/api/equality:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",
-        "//vendor/k8s.io/apimachinery/pkg/runtime/serializer:go_default_library",
         "//vendor/k8s.io/client-go/kubernetes:go_default_library",
     ],
 )

pkg/kubelet/kubeletconfig/checkpoint/checkpoint.go

@@ -30,7 +30,7 @@ import (
 type Checkpoint interface {
 	// UID returns the UID of the config source object behind the Checkpoint
 	UID() string
-	// Parse extracts the KubeletConfiguration from the checkpoint, applies defaults, and converts to the internal type
+	// Parse parses the checkpoint into the internal KubeletConfiguration type
 	Parse() (*kubeletconfig.KubeletConfiguration, error)
 	// Encode returns a []byte representation of the config source object behind the Checkpoint
 	Encode() ([]byte, error)
@@ -56,7 +56,6 @@ func DecodeCheckpoint(data []byte) (Checkpoint, error) {
 	if err != nil {
 		return nil, fmt.Errorf("failed to convert decoded object into a v1 ConfigMap, error: %v", err)
 	}
-
 	return NewConfigMapCheckpoint(cm)
 }
 

pkg/kubelet/kubeletconfig/checkpoint/checkpoint_test.go

@@ -30,6 +30,20 @@ import (
 	utiltest "k8s.io/kubernetes/pkg/kubelet/kubeletconfig/util/test"
 )
 
+// newUnsupportedEncoded returns an encoding of an object that does not have a Checkpoint implementation
+func newUnsupportedEncoded(t *testing.T) []byte {
+	encoder, err := utilcodec.NewJSONEncoder(apiv1.GroupName)
+	if err != nil {
+		t.Fatalf("could not create an encoder, error: %v", err)
+	}
+	unsupported := &apiv1.Node{}
+	data, err := runtime.Encode(encoder, unsupported)
+	if err != nil {
+		t.Fatalf("could not encode object, error: %v", err)
+	}
+	return data
+}
+
 func TestDecodeCheckpoint(t *testing.T) {
 	// generate correct Checkpoint for v1/ConfigMap test case
 	cm, err := NewConfigMapCheckpoint(&apiv1.ConfigMap{ObjectMeta: metav1.ObjectMeta{UID: types.UID("uid")}})
@@ -73,17 +87,3 @@ func TestDecodeCheckpoint(t *testing.T) {
 		}
 	}
 }
-
-// newUnsupportedEncoded returns an encoding of an object that does not have a Checkpoint implementation
-func newUnsupportedEncoded(t *testing.T) []byte {
-	encoder, err := utilcodec.NewJSONEncoder(apiv1.GroupName)
-	if err != nil {
-		t.Fatalf("could not create an encoder, error: %v", err)
-	}
-	unsupported := &apiv1.Node{}
-	data, err := runtime.Encode(encoder, unsupported)
-	if err != nil {
-		t.Fatalf("could not encode object, error: %v", err)
-	}
-	return data
-}

pkg/kubelet/kubeletconfig/checkpoint/configmap.go

@@ -21,9 +21,7 @@ import (
 
 	apiv1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/runtime"
-	"k8s.io/apimachinery/pkg/runtime/serializer"
 	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig"
-	kubeletscheme "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/scheme"
 	utilcodec "k8s.io/kubernetes/pkg/kubelet/kubeletconfig/util/codec"
 )
 
@@ -31,7 +29,6 @@ const configMapConfigKey = "kubelet"
 
 // configMapCheckpoint implements Checkpoint, backed by a v1/ConfigMap config source object
 type configMapCheckpoint struct {
-	kubeletCodecs *serializer.CodecFactory // codecs for the KubeletConfiguration
 	configMap *apiv1.ConfigMap
 }
 
@@ -43,13 +40,7 @@ func NewConfigMapCheckpoint(cm *apiv1.ConfigMap) (Checkpoint, error) {
 	} else if len(cm.ObjectMeta.UID) == 0 {
 		return nil, fmt.Errorf("ConfigMap must have a UID to be treated as a Checkpoint")
 	}
-
+	return &configMapCheckpoint{cm}, nil
-	_, kubeletCodecs, err := kubeletscheme.NewSchemeAndCodecs()
-	if err != nil {
-		return nil, err
-	}
-
-	return &configMapCheckpoint{kubeletCodecs, cm}, nil
 }
 
 // UID returns the UID of a configMapCheckpoint
@@ -57,23 +48,25 @@ func (c *configMapCheckpoint) UID() string {
 	return string(c.configMap.UID)
 }
 
-// Parse extracts the KubeletConfiguration from v1/ConfigMap checkpoints, applies defaults, and converts to the internal type
+// implements Parse for v1/ConfigMap checkpoints
 func (c *configMapCheckpoint) Parse() (*kubeletconfig.KubeletConfiguration, error) {
 	const emptyCfgErr = "config was empty, but some parameters are required"
 
-	if len(c.configMap.Data) == 0 {
+	cm := c.configMap
+
+	if len(cm.Data) == 0 {
 		return nil, fmt.Errorf(emptyCfgErr)
 	}
 
 	// TODO(mtaufen): Once the KubeletConfiguration type is decomposed, extend this to a key for each sub-object
-	config, ok := c.configMap.Data[configMapConfigKey]
+	config, ok := cm.Data[configMapConfigKey]
 	if !ok {
 		return nil, fmt.Errorf("key %q not found in ConfigMap", configMapConfigKey)
 	} else if len(config) == 0 {
 		return nil, fmt.Errorf(emptyCfgErr)
 	}
 
-	return utilcodec.DecodeKubeletConfiguration(c.kubeletCodecs, []byte(config))
+	return utilcodec.DecodeKubeletConfiguration([]byte(config))
 }
 
 // Encode encodes a configMapCheckpoint

pkg/kubelet/kubeletconfig/checkpoint/configmap_test.go

@@ -26,8 +26,8 @@ import (
 	apiequality "k8s.io/apimachinery/pkg/api/equality"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig"
-	kubeletscheme "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/scheme"
 	kubeletconfigv1alpha1 "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/v1alpha1"
 	utiltest "k8s.io/kubernetes/pkg/kubelet/kubeletconfig/util/test"
 )
@@ -66,15 +66,9 @@ func TestNewConfigMapCheckpoint(t *testing.T) {
 }
 
 func TestConfigMapCheckpointUID(t *testing.T) {
-	_, kubeletCodecs, err := kubeletscheme.NewSchemeAndCodecs()
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-
 	cases := []string{"", "uid", "376dfb73-56db-11e7-a01e-42010a800002"}
 	for _, uidIn := range cases {
 		cpt := &configMapCheckpoint{
-			kubeletCodecs,
 			&apiv1.ConfigMap{
 				ObjectMeta: metav1.ObjectMeta{UID: types.UID(uidIn)},
 			},
@@ -88,16 +82,11 @@ func TestConfigMapCheckpointUID(t *testing.T) {
 }
 
 func TestConfigMapCheckpointParse(t *testing.T) {
-	kubeletScheme, kubeletCodecs, err := kubeletscheme.NewSchemeAndCodecs()
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-
 	// get the built-in default configuration
 	external := &kubeletconfigv1alpha1.KubeletConfiguration{}
-	kubeletScheme.Default(external)
+	api.Scheme.Default(external)
 	defaultConfig := &kubeletconfig.KubeletConfiguration{}
-	err = kubeletScheme.Convert(external, defaultConfig, nil)
+	err := api.Scheme.Convert(external, defaultConfig, nil)
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -134,7 +123,7 @@ apiVersion: kubeletconfig/v1alpha1`}}, defaultConfig, ""},
 			"kubelet": `{"kind":"KubeletConfiguration","apiVersion":"kubeletconfig/v1alpha1"}`}}, defaultConfig, ""},
 	}
 	for _, c := range cases {
-		cpt := &configMapCheckpoint{kubeletCodecs, c.cm}
+		cpt := &configMapCheckpoint{c.cm}
 		kc, err := cpt.Parse()
 		if utiltest.SkipRest(t, c.desc, err, c.err) {
 			continue
@@ -147,11 +136,6 @@ apiVersion: kubeletconfig/v1alpha1`}}, defaultConfig, ""},
 }
 
 func TestConfigMapCheckpointEncode(t *testing.T) {
-	_, kubeletCodecs, err := kubeletscheme.NewSchemeAndCodecs()
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-
 	// only one case, based on output from the existing encoder, and since
 	// this is hard to test (key order isn't guaranteed), we should probably
 	// just stick to this test case and mostly rely on the round-trip test.
@@ -162,7 +146,7 @@ func TestConfigMapCheckpointEncode(t *testing.T) {
 	}{
 		// we expect Checkpoints to be encoded as a json representation of the underlying API object
 		{"one-key",
-			&configMapCheckpoint{kubeletCodecs, &apiv1.ConfigMap{
+			&configMapCheckpoint{&apiv1.ConfigMap{
 				ObjectMeta: metav1.ObjectMeta{Name: "one-key"},
 				Data:       map[string]string{"one": ""}}},
 			`{"kind":"ConfigMap","apiVersion":"v1","metadata":{"name":"one-key","creationTimestamp":null},"data":{"one":""}}
@@ -182,11 +166,6 @@ func TestConfigMapCheckpointEncode(t *testing.T) {
 }
 
 func TestConfigMapCheckpointRoundTrip(t *testing.T) {
-	_, kubeletCodecs, err := kubeletscheme.NewSchemeAndCodecs()
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-
 	cases := []struct {
 		desc      string
 		cpt       *configMapCheckpoint
@@ -194,7 +173,7 @@ func TestConfigMapCheckpointRoundTrip(t *testing.T) {
 	}{
 		// empty data
 		{"empty data",
-			&configMapCheckpoint{kubeletCodecs, &apiv1.ConfigMap{
+			&configMapCheckpoint{&apiv1.ConfigMap{
 				ObjectMeta: metav1.ObjectMeta{
 					Name: "empty-data-sha256-e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
 					UID:  "uid",
@@ -203,7 +182,7 @@ func TestConfigMapCheckpointRoundTrip(t *testing.T) {
 			""},
 		// two keys
 		{"two keys",
-			&configMapCheckpoint{kubeletCodecs, &apiv1.ConfigMap{
+			&configMapCheckpoint{&apiv1.ConfigMap{
 				ObjectMeta: metav1.ObjectMeta{
 					Name: "two-keys-sha256-2bff03d6249c8a9dc9a1436d087c124741361ccfac6615b81b67afcff5c42431",
 					UID:  "uid",
@@ -212,7 +191,7 @@ func TestConfigMapCheckpointRoundTrip(t *testing.T) {
 			""},
 		// missing uid
 		{"missing uid",
-			&configMapCheckpoint{kubeletCodecs, &apiv1.ConfigMap{
+			&configMapCheckpoint{&apiv1.ConfigMap{
 				ObjectMeta: metav1.ObjectMeta{
 					Name: "two-keys-sha256-2bff03d6249c8a9dc9a1436d087c124741361ccfac6615b81b67afcff5c42431",
 					UID:  "",

pkg/kubelet/kubeletconfig/checkpoint/download.go

@@ -113,6 +113,7 @@ func (r *remoteConfigMap) UID() string {
 
 func (r *remoteConfigMap) Download(client clientset.Interface) (Checkpoint, string, error) {
 	var reason string
+
 	uid := string(r.source.ConfigMapRef.UID)
 
 	utillog.Infof("attempting to download ConfigMap with UID %q", uid)
@@ -130,14 +131,8 @@ func (r *remoteConfigMap) Download(client clientset.Interface) (Checkpoint, stri
 		return nil, reason, fmt.Errorf(reason)
 	}
 
-	checkpoint, err := NewConfigMapCheckpoint(cm)
-	if err != nil {
-		reason = fmt.Sprintf("invalid downloaded object")
-		return nil, reason, fmt.Errorf("%s, error: %v", reason, err)
-	}
-
 	utillog.Infof("successfully downloaded ConfigMap with UID %q", uid)
-	return checkpoint, "", nil
+	return &configMapCheckpoint{cm}, "", nil
 }
 
 func (r *remoteConfigMap) Encode() ([]byte, error) {

pkg/kubelet/kubeletconfig/checkpoint/download_test.go

@@ -26,7 +26,6 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
 	fakeclient "k8s.io/client-go/kubernetes/fake"
-	kubeletscheme "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/scheme"
 	utiltest "k8s.io/kubernetes/pkg/kubelet/kubeletconfig/util/test"
 )
 
@@ -93,11 +92,6 @@ func TestRemoteConfigMapUID(t *testing.T) {
 }
 
 func TestRemoteConfigMapDownload(t *testing.T) {
-	_, kubeletCodecs, err := kubeletscheme.NewSchemeAndCodecs()
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-
 	cm := &apiv1.ConfigMap{
 		ObjectMeta: metav1.ObjectMeta{
 			Name:      "name",
@@ -124,7 +118,7 @@ func TestRemoteConfigMapDownload(t *testing.T) {
 		// successful download
 		{"object exists and reference is correct",
 			&remoteConfigMap{&apiv1.NodeConfigSource{ConfigMapRef: &apiv1.ObjectReference{Name: "name", Namespace: "namespace", UID: "uid"}}},
-			&configMapCheckpoint{kubeletCodecs, cm}, ""},
+			&configMapCheckpoint{cm}, ""},
 	}
 
 	for _, c := range cases {

pkg/kubelet/kubeletconfig/configfiles/BUILD

@@ -10,10 +10,8 @@ go_library(
     srcs = ["configfiles.go"],
     deps = [
         "//pkg/kubelet/apis/kubeletconfig:go_default_library",
-        "//pkg/kubelet/apis/kubeletconfig/scheme:go_default_library",
         "//pkg/kubelet/kubeletconfig/util/codec:go_default_library",
         "//pkg/kubelet/kubeletconfig/util/filesystem:go_default_library",
-        "//vendor/k8s.io/apimachinery/pkg/runtime/serializer:go_default_library",
     ],
 )
 

pkg/kubelet/kubeletconfig/configfiles/configfiles.go

@@ -20,9 +20,7 @@ import (
 	"fmt"
 	"path/filepath"
 
-	"k8s.io/apimachinery/pkg/runtime/serializer"
 	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig"
-	kubeletscheme "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/scheme"
 	utilcodec "k8s.io/kubernetes/pkg/kubelet/kubeletconfig/util/codec"
 	utilfs "k8s.io/kubernetes/pkg/kubelet/kubeletconfig/util/filesystem"
 )
@@ -37,24 +35,16 @@ type Loader interface {
 type fsLoader struct {
 	// fs is the filesystem where the config files exist; can be mocked for testing
 	fs utilfs.Filesystem
-	// kubeletCodecs is the scheme used to decode config files
-	kubeletCodecs *serializer.CodecFactory
 	// configDir is the absolute path to the directory containing the configuration files
 	configDir string
 }
 
 // NewFSLoader returns a Loader that loads a KubeletConfiguration from the files in `configDir`
-func NewFSLoader(fs utilfs.Filesystem, configDir string) (Loader, error) {
+func NewFSLoader(fs utilfs.Filesystem, configDir string) Loader {
-	_, kubeletCodecs, err := kubeletscheme.NewSchemeAndCodecs()
-	if err != nil {
-		return nil, err
-	}
-
 	return &fsLoader{
 		fs:        fs,
-		kubeletCodecs: kubeletCodecs,
 		configDir: configDir,
-	}, nil
+	}
 }
 
 func (loader *fsLoader) Load() (*kubeletconfig.KubeletConfiguration, error) {
@@ -72,5 +62,5 @@ func (loader *fsLoader) Load() (*kubeletconfig.KubeletConfiguration, error) {
 		return nil, fmt.Errorf(errfmt, fmt.Errorf("config file was empty, but some parameters are required"))
 	}
 
-	return utilcodec.DecodeKubeletConfiguration(loader.kubeletCodecs, data)
+	return utilcodec.DecodeKubeletConfiguration(data)
 }

pkg/kubelet/kubeletconfig/controller.go

@@ -53,7 +53,7 @@ const (
 // - validates configuration
 // - monitors for potential crash-loops caused by new configurations
 // - tracks the last-known-good configuration, and rolls-back to last-known-good when necessary
-// For more information, see the proposal: https://github.com/kubernetes/community/blob/master/contributors/design-proposals/dynamic-kubelet-configuration.md
+// For more information, see the proposal: https://github.com/kubernetes/kubernetes/pull/29459
 type Controller struct {
 	// dynamicConfig, if true, indicates that we should sync config from the API server
 	dynamicConfig bool
@@ -90,19 +90,12 @@ type Controller struct {
 // If the `initConfigDir` is an empty string, skips trying to load the init config.
 // If the `dynamicConfigDir` is an empty string, skips trying to load checkpoints or download new config,
 // but will still sync the ConfigOK condition if you call StartSync with a non-nil client.
-func NewController(initConfigDir string,
+func NewController(initConfigDir string, dynamicConfigDir string, defaultConfig *kubeletconfig.KubeletConfiguration) *Controller {
-	dynamicConfigDir string,
-	defaultConfig *kubeletconfig.KubeletConfiguration) (*Controller, error) {
-	var err error
-
 	fs := utilfs.DefaultFs{}
 
 	var initLoader configfiles.Loader
 	if len(initConfigDir) > 0 {
-		initLoader, err = configfiles.NewFSLoader(fs, initConfigDir)
+		initLoader = configfiles.NewFSLoader(fs, initConfigDir)
-		if err != nil {
-			return nil, err
-		}
 	}
 	dynamicConfig := false
 	if len(dynamicConfigDir) > 0 {
@@ -127,7 +120,7 @@ func NewController(initConfigDir string,
 		badConfigTracker:    badconfig.NewFsTracker(fs, filepath.Join(dynamicConfigDir, badConfigTrackingDir, kubeletVersion)),
 		startupTracker:      startups.NewFsTracker(fs, filepath.Join(dynamicConfigDir, startupTrackingDir, kubeletVersion)),
 		initLoader:          initLoader,
-	}, nil
+	}
 }
 
 // Bootstrap attempts to return a valid KubeletConfiguration based on the configuration of the Controller,

pkg/kubelet/kubeletconfig/util/codec/BUILD

@@ -12,8 +12,9 @@ go_library(
         "//pkg/api:go_default_library",
         "//pkg/api/install:go_default_library",
         "//pkg/kubelet/apis/kubeletconfig:go_default_library",
+        "//pkg/kubelet/apis/kubeletconfig/install:go_default_library",
+        "//pkg/kubelet/apis/kubeletconfig/v1alpha1:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",
-        "//vendor/k8s.io/apimachinery/pkg/runtime/serializer:go_default_library",
     ],
 )
 

pkg/kubelet/kubeletconfig/util/codec/codec.go

@@ -21,11 +21,13 @@ import (
 
 	// ensure the core apis are installed
 	_ "k8s.io/kubernetes/pkg/api/install"
+	// ensure the kubeletconfig apis are installed
+	_ "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/install"
 
 	"k8s.io/apimachinery/pkg/runtime"
-	"k8s.io/apimachinery/pkg/runtime/serializer"
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig"
+	kubeletconfigv1alpha1 "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/v1alpha1"
 )
 
 // TODO(mtaufen): allow an encoder to be injected into checkpoint objects at creation time? (then we could ultimately instantiate only one encoder)
@@ -48,18 +50,28 @@ func NewJSONEncoder(groupName string) (runtime.Encoder, error) {
 	return api.Codecs.EncoderForVersion(info.Serializer, versions[0]), nil
 }
 
-// DecodeKubeletConfiguration decodes a serialized KubeletConfiguration to the internal type
+// DecodeKubeletConfiguration decodes an encoded (v1alpha1) KubeletConfiguration object to the internal type
-func DecodeKubeletConfiguration(kubeletCodecs *serializer.CodecFactory, data []byte) (*kubeletconfig.KubeletConfiguration, error) {
+func DecodeKubeletConfiguration(data []byte) (*kubeletconfig.KubeletConfiguration, error) {
-	// the UniversalDecoder runs defaulting and returns the internal type by default
+	// decode the object, note we use the external version scheme to decode, because users provide the external version
-	obj, gvk, err := kubeletCodecs.UniversalDecoder().Decode(data, nil, nil)
+	obj, err := runtime.Decode(api.Codecs.UniversalDecoder(kubeletconfigv1alpha1.SchemeGroupVersion), data)
 	if err != nil {
 		return nil, fmt.Errorf("failed to decode, error: %v", err)
 	}
 
-	internalKC, ok := obj.(*kubeletconfig.KubeletConfiguration)
+	externalKC, ok := obj.(*kubeletconfigv1alpha1.KubeletConfiguration)
 	if !ok {
-		return nil, fmt.Errorf("failed to cast object to KubeletConfiguration, unexpected type: %v", gvk)
+		return nil, fmt.Errorf("failed to cast object to KubeletConfiguration, object: %#v", obj)
 	}
 
+	// TODO(mtaufen): confirm whether api.Codecs.UniversalDecoder runs the defaulting, which would make this redundant
+	// run the defaulter on the decoded configuration before converting to internal type
+	api.Scheme.Default(externalKC)
+
+	// convert to internal type
+	internalKC := &kubeletconfig.KubeletConfiguration{}
+	err = api.Scheme.Convert(externalKC, internalKC, nil)
+	if err != nil {
+		return nil, err
+	}
 	return internalKC, nil
 }

test/e2e_node/BUILD

@@ -30,7 +30,6 @@ go_library(
         "//pkg/kubelet/apis/cri:go_default_library",
         "//pkg/kubelet/apis/cri/v1alpha1/runtime:go_default_library",
         "//pkg/kubelet/apis/kubeletconfig:go_default_library",
-        "//pkg/kubelet/apis/kubeletconfig/scheme:go_default_library",
         "//pkg/kubelet/apis/kubeletconfig/v1alpha1:go_default_library",
         "//pkg/kubelet/apis/stats/v1alpha1:go_default_library",
         "//pkg/kubelet/metrics:go_default_library",

test/e2e_node/util.go

@@ -37,7 +37,6 @@ import (
 	"k8s.io/client-go/kubernetes/scheme"
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig"
-	kubeletscheme "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/scheme"
 	kubeletconfigv1alpha1 "k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/v1alpha1"
 	stats "k8s.io/kubernetes/pkg/kubelet/apis/stats/v1alpha1"
 	kubeletmetrics "k8s.io/kubernetes/pkg/kubelet/metrics"
@@ -263,7 +262,7 @@ func makeKubeletConfigMap(internalKC *kubeletconfig.KubeletConfiguration) *v1.Co
 	externalKC := &kubeletconfigv1alpha1.KubeletConfiguration{}
 	api.Scheme.Convert(internalKC, externalKC, nil)
 
-	encoder, err := newKubeletConfigJSONEncoder()
+	encoder, err := newJSONEncoder(kubeletconfig.GroupName)
 	framework.ExpectNoError(err)
 
 	data, err := runtime.Encode(encoder, externalKC)
@@ -311,18 +310,21 @@ func logKubeletMetrics(metricKeys ...string) {
 	}
 }
 
-func newKubeletConfigJSONEncoder() (runtime.Encoder, error) {
+func newJSONEncoder(groupName string) (runtime.Encoder, error) {
-	_, kubeletCodecs, err := kubeletscheme.NewSchemeAndCodecs()
+	// encode to json
-	if err != nil {
-		return nil, err
-	}
-
 	mediaType := "application/json"
-	info, ok := runtime.SerializerInfoForMediaType(kubeletCodecs.SupportedMediaTypes(), mediaType)
+	info, ok := runtime.SerializerInfoForMediaType(api.Codecs.SupportedMediaTypes(), mediaType)
 	if !ok {
 		return nil, fmt.Errorf("unsupported media type %q", mediaType)
 	}
-	return kubeletCodecs.EncoderForVersion(info.Serializer, kubeletconfigv1alpha1.SchemeGroupVersion), nil
+
+	versions := api.Registry.EnabledVersionsForGroup(groupName)
+	if len(versions) == 0 {
+		return nil, fmt.Errorf("no enabled versions for group %q", groupName)
+	}
+
+	// the "best" version supposedly comes first in the list returned from api.Registry.EnabledVersionsForGroup
+	return api.Codecs.EncoderForVersion(info.Serializer, versions[0]), nil
 }
 
 // runCommand runs the cmd and returns the combined stdout and stderr, or an

test/integration/etcd/etcd_storage_path_test.go

@@ -434,6 +434,10 @@ var ephemeralWhiteList = createEphemeralWhiteList(
 	gvr("componentconfig", "v1alpha1", "kubeproxyconfigurations"),     // not stored in etcd
 	// --
 
+	// k8s.io/kubernetes/pkg/kubelet/apis/kubeletconfig/v1alpha1
+	gvr("kubeletconfig", "v1alpha1", "kubeletconfigurations"), // not stored in etcd
+	// --
+
 	// k8s.io/kubernetes/pkg/apis/extensions/v1beta1
 	gvr("extensions", "v1beta1", "deploymentrollbacks"),          // used to rollback deployment, not stored in etcd
 	gvr("extensions", "v1beta1", "replicationcontrollerdummies"), // not stored in etcd