kubelet tracing

Signed-off-by: Sally O'Malley <somalley@redhat.com>
Co-authored-by: David Ashpole <dashpole@google.com>

cmd/kube-apiserver/app/options/options_test.go

@@ -25,6 +25,7 @@ import (
 	"github.com/google/go-cmp/cmp"
 	"github.com/google/go-cmp/cmp/cmpopts"
 	"github.com/spf13/pflag"
+	oteltrace "go.opentelemetry.io/otel/trace"
 	"k8s.io/apiserver/pkg/admission"
 	apiserveroptions "k8s.io/apiserver/pkg/server/options"
 	"k8s.io/apiserver/pkg/storage/etcd3"
@@ -153,10 +154,11 @@ func TestAddFlags(t *testing.T) {
 			StorageConfig: storagebackend.Config{
 				Type: "etcd3",
 				Transport: storagebackend.TransportConfig{
-					ServerList:    nil,
-					KeyFile:       "/var/run/kubernetes/etcd.key",
-					TrustedCAFile: "/var/run/kubernetes/etcdca.crt",
-					CertFile:      "/var/run/kubernetes/etcdce.crt",
+					ServerList:     nil,
+					KeyFile:        "/var/run/kubernetes/etcd.key",
+					TrustedCAFile:  "/var/run/kubernetes/etcdca.crt",
+					CertFile:       "/var/run/kubernetes/etcdce.crt",
+					TracerProvider: oteltrace.NewNoopTracerProvider(),
 				},
 				Paging:                true,
 				Prefix:                "/registry",

cmd/kube-apiserver/app/server.go

@@ -31,6 +31,8 @@ import (
 
 	"github.com/spf13/cobra"
 
+	oteltrace "go.opentelemetry.io/otel/trace"
+
 	extensionsapiserver "k8s.io/apiextensions-apiserver/pkg/apiserver"
 	utilerrors "k8s.io/apimachinery/pkg/util/errors"
 	utilnet "k8s.io/apimachinery/pkg/util/net"
@@ -417,8 +419,10 @@ func buildGenericConfig(
 	if genericConfig.EgressSelector != nil {
 		storageFactory.StorageConfig.Transport.EgressLookup = genericConfig.EgressSelector.Lookup
 	}
-	if utilfeature.DefaultFeatureGate.Enabled(genericfeatures.APIServerTracing) && genericConfig.TracerProvider != nil {
+	if utilfeature.DefaultFeatureGate.Enabled(genericfeatures.APIServerTracing) {
 		storageFactory.StorageConfig.Transport.TracerProvider = genericConfig.TracerProvider
+	} else {
+		storageFactory.StorageConfig.Transport.TracerProvider = oteltrace.NewNoopTracerProvider()
 	}
 	if lastErr = s.Etcd.ApplyWithStorageFactoryTo(storageFactory, genericConfig); lastErr != nil {
 		return

cmd/kubelet/app/server.go

@@ -39,6 +39,10 @@ import (
 	"k8s.io/mount-utils"
 
 	cadvisorapi "github.com/google/cadvisor/info/v1"
+	"go.opentelemetry.io/otel/exporters/otlp/otlpgrpc"
+	otelsdkresource "go.opentelemetry.io/otel/sdk/resource"
+	"go.opentelemetry.io/otel/semconv"
+	oteltrace "go.opentelemetry.io/otel/trace"
 	v1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
 	"k8s.io/apimachinery/pkg/runtime"
@@ -68,6 +72,7 @@ import (
 	logsapi "k8s.io/component-base/logs/api/v1"
 	"k8s.io/component-base/metrics"
 	"k8s.io/component-base/metrics/legacyregistry"
+	tracing "k8s.io/component-base/tracing"
 	"k8s.io/component-base/version"
 	"k8s.io/component-base/version/verflag"
 	kubeletconfigv1beta1 "k8s.io/kubelet/config/v1beta1"
@@ -373,6 +378,13 @@ func UnsecuredDependencies(s *options.KubeletServer, featureGate featuregate.Fea
 	if err != nil {
 		return nil, err
 	}
+	tp := oteltrace.NewNoopTracerProvider()
+	if utilfeature.DefaultFeatureGate.Enabled(features.KubeletTracing) {
+		tp, err = newTracerProvider(s)
+		if err != nil {
+			return nil, err
+		}
+	}
 	return &kubelet.Dependencies{
 		Auth:                nil, // default does not enforce auth[nz]
 		CAdvisorInterface:   nil, // cadvisor.New launches background processes (bg http.ListenAndServe, and some bg cleaners), not set here
@@ -381,6 +393,7 @@ func UnsecuredDependencies(s *options.KubeletServer, featureGate featuregate.Fea
 		KubeClient:          nil,
 		HeartbeatClient:     nil,
 		EventClient:         nil,
+		TracerProvider:      tp,
 		HostUtil:            hu,
 		Mounter:             mounter,
 		Subpather:           subpather,
@@ -563,7 +576,7 @@ func run(ctx context.Context, s *options.KubeletServer, kubeDeps *kubelet.Depend
 		klog.InfoS("Standalone mode, no API client")
 
 	case kubeDeps.KubeClient == nil, kubeDeps.EventClient == nil, kubeDeps.HeartbeatClient == nil:
-		clientConfig, onHeartbeatFailure, err := buildKubeletClientConfig(ctx, s, nodeName)
+		clientConfig, onHeartbeatFailure, err := buildKubeletClientConfig(ctx, s, kubeDeps.TracerProvider, nodeName)
 		if err != nil {
 			return err
 		}
@@ -790,7 +803,7 @@ func run(ctx context.Context, s *options.KubeletServer, kubeDeps *kubelet.Depend
 
 // buildKubeletClientConfig constructs the appropriate client config for the kubelet depending on whether
 // bootstrapping is enabled or client certificate rotation is enabled.
-func buildKubeletClientConfig(ctx context.Context, s *options.KubeletServer, nodeName types.NodeName) (*restclient.Config, func(), error) {
+func buildKubeletClientConfig(ctx context.Context, s *options.KubeletServer, tp oteltrace.TracerProvider, nodeName types.NodeName) (*restclient.Config, func(), error) {
 	if s.RotateCertificates {
 		// Rules for client rotation and the handling of kube config files:
 		//
@@ -905,6 +918,9 @@ func buildKubeletClientConfig(ctx context.Context, s *options.KubeletServer, nod
 			utilnet.CloseIdleConnectionsFor(clientConfig.Transport)
 		}
 	}
+	if utilfeature.DefaultFeatureGate.Enabled(features.KubeletTracing) {
+		clientConfig.Wrap(tracing.WrapperFor(tp))
+	}
 	return clientConfig, onHeartbeatFailure, nil
 }
 
@@ -1167,7 +1183,7 @@ func startKubelet(k kubelet.Bootstrap, podCfg *config.PodConfig, kubeCfg *kubele
 
 	// start the kubelet server
 	if enableServer {
-		go k.ListenAndServe(kubeCfg, kubeDeps.TLSOptions, kubeDeps.Auth)
+		go k.ListenAndServe(kubeCfg, kubeDeps.TLSOptions, kubeDeps.Auth, kubeDeps.TracerProvider)
 	}
 	if kubeCfg.ReadOnlyPort > 0 {
 		go k.ListenAndServeReadOnly(netutils.ParseIPSloppy(kubeCfg.Address), uint(kubeCfg.ReadOnlyPort))
@@ -1250,3 +1266,24 @@ func parseResourceList(m map[string]string) (v1.ResourceList, error) {
 	}
 	return rl, nil
 }
+
+func newTracerProvider(s *options.KubeletServer) (oteltrace.TracerProvider, error) {
+	if s.KubeletConfiguration.Tracing == nil {
+		return oteltrace.NewNoopTracerProvider(), nil
+	}
+	hostname, err := nodeutil.GetHostname(s.HostnameOverride)
+	if err != nil {
+		return nil, fmt.Errorf("could not determine hostname for tracer provider: %v", err)
+	}
+	resourceOpts := []otelsdkresource.Option{
+		otelsdkresource.WithAttributes(
+			semconv.ServiceNameKey.String(componentKubelet),
+			semconv.HostNameKey.String(hostname),
+		),
+	}
+	tp, err := tracing.NewProvider(context.Background(), s.KubeletConfiguration.Tracing, []otlpgrpc.Option{}, resourceOpts)
+	if err != nil {
+		return nil, fmt.Errorf("could not configure tracer provider: %v", err)
+	}
+	return tp, nil
+}

cmd/kubemark/hollow-node.go

@@ -26,6 +26,7 @@ import (
 
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
+	oteltrace "go.opentelemetry.io/otel/trace"
 	internalapi "k8s.io/cri-api/pkg/apis"
 	"k8s.io/klog/v2"
 
@@ -246,7 +247,7 @@ func run(cmd *cobra.Command, config *hollowNodeConfig) error {
 			return fmt.Errorf("Failed to start fake runtime, error: %w", err)
 		}
 		defer fakeRemoteRuntime.Stop()
-		runtimeService, err := remote.NewRemoteRuntimeService(endpoint, 15*time.Second)
+		runtimeService, err := remote.NewRemoteRuntimeService(endpoint, 15*time.Second, oteltrace.NewNoopTracerProvider())
 		if err != nil {
 			return fmt.Errorf("Failed to init runtime service, error: %w", err)
 		}

pkg/features/kube_features.go

@@ -498,6 +498,13 @@ const (
 	// Enable POD resources API to return allocatable resources
 	KubeletPodResourcesGetAllocatable featuregate.Feature = "KubeletPodResourcesGetAllocatable"
 
+	// owner: @sallyom
+	// kep: http://kep.k8s.io/2832
+	// alpha: v1.25
+	//
+	// Add support for distributed tracing in the kubelet
+	KubeletTracing featuregate.Feature = "KubeletTracing"
+
 	// owner: @zshihang
 	// kep: http://kep.k8s.io/2800
 	// beta: v1.24
@@ -961,6 +968,8 @@ var defaultKubernetesFeatureGates = map[featuregate.Feature]featuregate.FeatureS
 
 	KubeletPodResourcesGetAllocatable: {Default: true, PreRelease: featuregate.Beta},
 
+	KubeletTracing: {Default: false, PreRelease: featuregate.Alpha},
+
 	LegacyServiceAccountTokenNoAutoGeneration: {Default: true, PreRelease: featuregate.Beta},
 
 	LocalStorageCapacityIsolation: {Default: true, PreRelease: featuregate.Beta},

pkg/kubeapiserver/admission/config.go

@@ -47,7 +47,7 @@ type Config struct {
 }
 
 // New sets up the plugins and admission start hooks needed for admission
-func (c *Config) New(proxyTransport *http.Transport, egressSelector *egressselector.EgressSelector, serviceResolver webhook.ServiceResolver, tp *trace.TracerProvider) ([]admission.PluginInitializer, genericapiserver.PostStartHookFunc, error) {
+func (c *Config) New(proxyTransport *http.Transport, egressSelector *egressselector.EgressSelector, serviceResolver webhook.ServiceResolver, tp trace.TracerProvider) ([]admission.PluginInitializer, genericapiserver.PostStartHookFunc, error) {
 	webhookAuthResolverWrapper := webhook.NewDefaultAuthenticationInfoResolverWrapper(proxyTransport, egressSelector, c.LoopbackClientConfig, tp)
 	webhookPluginInitializer := webhookinit.NewPluginInitializer(webhookAuthResolverWrapper, serviceResolver)
 

pkg/kubelet/apis/config/helpers_test.go

@@ -280,5 +280,7 @@ var (
 		"ShutdownGracePeriod.Duration",
 		"ShutdownGracePeriodCriticalPods.Duration",
 		"MemoryThrottlingFactor",
+		"Tracing.Endpoint",
+		"Tracing.SamplingRatePerMillion",
 	)
 )

pkg/kubelet/apis/config/register_test.go

@@ -24,6 +24,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	componentconfigtesting "k8s.io/component-base/config/testing"
 	logsapi "k8s.io/component-base/logs/api/v1"
+	tracingapi "k8s.io/component-base/tracing/api/v1"
 )
 
 func TestComponentConfigSetup(t *testing.T) {
@@ -33,11 +34,12 @@ func TestComponentConfigSetup(t *testing.T) {
 		SchemeGroupVersion: SchemeGroupVersion,
 		AddToScheme:        AddToScheme,
 		AllowedTags: map[reflect.Type]bool{
-			reflect.TypeOf(logsapi.LoggingConfiguration{}): true,
-			reflect.TypeOf(metav1.Duration{}):              true,
-			reflect.TypeOf(metav1.TypeMeta{}):              true,
-			reflect.TypeOf(v1.NodeConfigSource{}):          true,
-			reflect.TypeOf(v1.Taint{}):                     true,
+			reflect.TypeOf(logsapi.LoggingConfiguration{}):    true,
+			reflect.TypeOf(tracingapi.TracingConfiguration{}): true,
+			reflect.TypeOf(metav1.Duration{}):                 true,
+			reflect.TypeOf(metav1.TypeMeta{}):                 true,
+			reflect.TypeOf(v1.NodeConfigSource{}):             true,
+			reflect.TypeOf(v1.Taint{}):                        true,
 		},
 	}
 

pkg/kubelet/apis/config/types.go

@@ -20,6 +20,7 @@ import (
 	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	logsapi "k8s.io/component-base/logs/api/v1"
+	tracingapi "k8s.io/component-base/tracing/api/v1"
 )
 
 // HairpinMode denotes how the kubelet should configure networking to handle
@@ -441,10 +442,14 @@ type KubeletConfiguration struct {
 	// is true and upon the initial registration of the node.
 	// +optional
 	RegisterWithTaints []v1.Taint
-
 	// registerNode enables automatic registration with the apiserver.
 	// +optional
 	RegisterNode bool
+	// Tracing specifies the versioned configuration for OpenTelemetry tracing clients.
+	// See http://kep.k8s.io/2832 for more details.
+	// +featureGate=KubeletTracing
+	// +optional
+	Tracing *tracingapi.TracingConfiguration
 }
 
 // KubeletAuthorizationMode denotes the authorization mode for the kubelet

pkg/kubelet/apis/config/validation/validation.go

@@ -27,6 +27,7 @@ import (
 	"k8s.io/component-base/featuregate"
 	logsapi "k8s.io/component-base/logs/api/v1"
 	"k8s.io/component-base/metrics"
+	tracingapi "k8s.io/component-base/tracing/api/v1"
 	"k8s.io/kubernetes/pkg/features"
 	kubeletconfig "k8s.io/kubernetes/pkg/kubelet/apis/config"
 	"k8s.io/kubernetes/pkg/kubelet/cm/cpuset"
@@ -241,6 +242,14 @@ func ValidateKubeletConfiguration(kc *kubeletconfig.KubeletConfiguration, featur
 		allErrors = append(allErrors, errs.ToAggregate().Errors()...)
 	}
 
+	if localFeatureGate.Enabled(features.KubeletTracing) {
+		if errs := tracingapi.ValidateTracingConfiguration(kc.Tracing, localFeatureGate, field.NewPath("tracing")); len(errs) > 0 {
+			allErrors = append(allErrors, errs.ToAggregate().Errors()...)
+		}
+	} else if kc.Tracing != nil {
+		allErrors = append(allErrors, fmt.Errorf("invalid configuration: tracing should not be configured if KubeletTracing feature flag is disabled."))
+	}
+
 	if localFeatureGate.Enabled(features.MemoryQoS) && kc.MemoryThrottlingFactor == nil {
 		allErrors = append(allErrors, fmt.Errorf("invalid configuration: memoryThrottlingFactor is required when MemoryQoS feature flag is enabled"))
 	}

pkg/kubelet/apis/config/validation/validation_test.go

@@ -25,6 +25,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	logsapi "k8s.io/component-base/logs/api/v1"
+	tracingapi "k8s.io/component-base/tracing/api/v1"
 	kubeletconfig "k8s.io/kubernetes/pkg/kubelet/apis/config"
 	"k8s.io/kubernetes/pkg/kubelet/apis/config/validation"
 	kubetypes "k8s.io/kubernetes/pkg/kubelet/types"
@@ -497,6 +498,36 @@ func TestValidateKubeletConfiguration(t *testing.T) {
 			},
 			errMsg: "invalid configuration: taint.TimeAdded is not nil",
 		},
+		{
+			name: "specify tracing with KubeletTracing disabled",
+			configure: func(conf *kubeletconfig.KubeletConfiguration) *kubeletconfig.KubeletConfiguration {
+				samplingRate := int32(99999)
+				conf.FeatureGates = map[string]bool{"KubeletTracing": false}
+				conf.Tracing = &tracingapi.TracingConfiguration{SamplingRatePerMillion: &samplingRate}
+				return conf
+			},
+			errMsg: "invalid configuration: tracing should not be configured if KubeletTracing feature flag is disabled.",
+		},
+		{
+			name: "specify tracing invalid sampling rate",
+			configure: func(conf *kubeletconfig.KubeletConfiguration) *kubeletconfig.KubeletConfiguration {
+				samplingRate := int32(-1)
+				conf.FeatureGates = map[string]bool{"KubeletTracing": true}
+				conf.Tracing = &tracingapi.TracingConfiguration{SamplingRatePerMillion: &samplingRate}
+				return conf
+			},
+			errMsg: "tracing.samplingRatePerMillion: Invalid value: -1: sampling rate must be positive",
+		},
+		{
+			name: "specify tracing invalid endpoint",
+			configure: func(conf *kubeletconfig.KubeletConfiguration) *kubeletconfig.KubeletConfiguration {
+				ep := "dn%2s://localhost:4317"
+				conf.FeatureGates = map[string]bool{"KubeletTracing": true}
+				conf.Tracing = &tracingapi.TracingConfiguration{Endpoint: &ep}
+				return conf
+			},
+			errMsg: "tracing.endpoint: Invalid value: \"dn%2s://localhost:4317\": parse \"dn%2s://localhost:4317\": first path segment in URL cannot contain colon",
+		},
 	}
 
 	for _, tc := range cases {

pkg/kubelet/cri/remote/remote_runtime.go

@@ -23,16 +23,20 @@ import (
 	"strings"
 	"time"
 
+	"go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc"
+	"go.opentelemetry.io/otel/trace"
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials/insecure"
 	"google.golang.org/grpc/status"
-	"k8s.io/klog/v2"
-
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/component-base/logs/logreduction"
+	tracing "k8s.io/component-base/tracing"
 	internalapi "k8s.io/cri-api/pkg/apis"
 	runtimeapi "k8s.io/cri-api/pkg/apis/runtime/v1"
 	runtimeapiV1alpha2 "k8s.io/cri-api/pkg/apis/runtime/v1alpha2"
+	"k8s.io/klog/v2"
+	"k8s.io/kubernetes/pkg/features"
 	"k8s.io/kubernetes/pkg/kubelet/util"
 	"k8s.io/kubernetes/pkg/probe/exec"
 	utilexec "k8s.io/utils/exec"
@@ -68,7 +72,7 @@ const (
 )
 
 // NewRemoteRuntimeService creates a new internalapi.RuntimeService.
-func NewRemoteRuntimeService(endpoint string, connectionTimeout time.Duration) (internalapi.RuntimeService, error) {
+func NewRemoteRuntimeService(endpoint string, connectionTimeout time.Duration, tp trace.TracerProvider) (internalapi.RuntimeService, error) {
 	klog.V(3).InfoS("Connecting to runtime service", "endpoint", endpoint)
 	addr, dialer, err := util.GetAddressAndDialer(endpoint)
 	if err != nil {
@@ -77,10 +81,23 @@ func NewRemoteRuntimeService(endpoint string, connectionTimeout time.Duration) (
 	ctx, cancel := context.WithTimeout(context.Background(), connectionTimeout)
 	defer cancel()
 
-	conn, err := grpc.DialContext(ctx, addr,
+	dialOpts := []grpc.DialOption{}
+	dialOpts = append(dialOpts,
 		grpc.WithTransportCredentials(insecure.NewCredentials()),
 		grpc.WithContextDialer(dialer),
 		grpc.WithDefaultCallOptions(grpc.MaxCallRecvMsgSize(maxMsgSize)))
+	if utilfeature.DefaultFeatureGate.Enabled(features.KubeletTracing) {
+		tracingOpts := []otelgrpc.Option{
+			otelgrpc.WithPropagators(tracing.Propagators()),
+			otelgrpc.WithTracerProvider(tp),
+		}
+		// Even if there is no TracerProvider, the otelgrpc still handles context propagation.
+		// See https://github.com/open-telemetry/opentelemetry-go/tree/main/example/passthrough
+		dialOpts = append(dialOpts,
+			grpc.WithUnaryInterceptor(otelgrpc.UnaryClientInterceptor(tracingOpts...)),
+			grpc.WithStreamInterceptor(otelgrpc.StreamClientInterceptor(tracingOpts...)))
+	}
+	conn, err := grpc.DialContext(ctx, addr, dialOpts...)
 	if err != nil {
 		klog.ErrorS(err, "Connect remote runtime failed", "address", addr)
 		return nil, err

pkg/kubelet/cri/remote/remote_runtime_test.go

@@ -21,6 +21,8 @@ import (
 	"testing"
 	"time"
 
+	oteltrace "go.opentelemetry.io/otel/trace"
+
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	internalapi "k8s.io/cri-api/pkg/apis"
@@ -47,7 +49,7 @@ func createAndStartFakeRemoteRuntime(t *testing.T) (*fakeremote.RemoteRuntime, s
 }
 
 func createRemoteRuntimeService(endpoint string, t *testing.T) internalapi.RuntimeService {
-	runtimeService, err := NewRemoteRuntimeService(endpoint, defaultConnectionTimeout)
+	runtimeService, err := NewRemoteRuntimeService(endpoint, defaultConnectionTimeout, oteltrace.NewNoopTracerProvider())
 	require.NoError(t, err)
 
 	return runtimeService

pkg/kubelet/kubelet.go

@@ -38,6 +38,7 @@ import (
 
 	cadvisorapi "github.com/google/cadvisor/info/v1"
 	libcontaineruserns "github.com/opencontainers/runc/libcontainer/userns"
+	"go.opentelemetry.io/otel/trace"
 	"k8s.io/mount-utils"
 	"k8s.io/utils/integer"
 	netutils "k8s.io/utils/net"
@@ -206,7 +207,7 @@ type Bootstrap interface {
 	GetConfiguration() kubeletconfiginternal.KubeletConfiguration
 	BirthCry()
 	StartGarbageCollection()
-	ListenAndServe(kubeCfg *kubeletconfiginternal.KubeletConfiguration, tlsOptions *server.TLSOptions, auth server.AuthInterface)
+	ListenAndServe(kubeCfg *kubeletconfiginternal.KubeletConfiguration, tlsOptions *server.TLSOptions, auth server.AuthInterface, tp trace.TracerProvider)
 	ListenAndServeReadOnly(address net.IP, port uint)
 	ListenAndServePodResources()
 	Run(<-chan kubetypes.PodUpdate)
@@ -236,6 +237,7 @@ type Dependencies struct {
 	ProbeManager         prober.Manager
 	Recorder             record.EventRecorder
 	Subpather            subpath.Interface
+	TracerProvider       trace.TracerProvider
 	VolumePlugins        []volume.VolumePlugin
 	DynamicPluginProber  volume.DynamicPluginProber
 	TLSOptions           *server.TLSOptions
@@ -293,7 +295,7 @@ func PreInitRuntimeService(kubeCfg *kubeletconfiginternal.KubeletConfiguration,
 	}
 
 	var err error
-	if kubeDeps.RemoteRuntimeService, err = remote.NewRemoteRuntimeService(remoteRuntimeEndpoint, kubeCfg.RuntimeRequestTimeout.Duration); err != nil {
+	if kubeDeps.RemoteRuntimeService, err = remote.NewRemoteRuntimeService(remoteRuntimeEndpoint, kubeCfg.RuntimeRequestTimeout.Duration, kubeDeps.TracerProvider); err != nil {
 		return err
 	}
 	if kubeDeps.RemoteImageService, err = remote.NewRemoteImageService(remoteImageEndpoint, kubeCfg.RuntimeRequestTimeout.Duration); err != nil {
@@ -2395,8 +2397,8 @@ func (kl *Kubelet) ResyncInterval() time.Duration {
 
 // ListenAndServe runs the kubelet HTTP server.
 func (kl *Kubelet) ListenAndServe(kubeCfg *kubeletconfiginternal.KubeletConfiguration, tlsOptions *server.TLSOptions,
-	auth server.AuthInterface) {
-	server.ListenAndServeKubeletServer(kl, kl.resourceAnalyzer, kubeCfg, tlsOptions, auth)
+	auth server.AuthInterface, tp trace.TracerProvider) {
+	server.ListenAndServeKubeletServer(kl, kl.resourceAnalyzer, kubeCfg, tlsOptions, auth, tp)
 }
 
 // ListenAndServeReadOnly runs the kubelet HTTP server in read-only mode.

pkg/kubelet/server/server.go

@@ -37,6 +37,7 @@ import (
 	cadvisorapi "github.com/google/cadvisor/info/v1"
 	cadvisorv2 "github.com/google/cadvisor/info/v2"
 	"github.com/google/cadvisor/metrics"
+	oteltrace "go.opentelemetry.io/otel/trace"
 	"google.golang.org/grpc"
 	"k8s.io/klog/v2"
 	"k8s.io/kubernetes/pkg/kubelet/metrics/collectors"
@@ -63,6 +64,7 @@ import (
 	compbasemetrics "k8s.io/component-base/metrics"
 	"k8s.io/component-base/metrics/legacyregistry"
 	runtimeapi "k8s.io/cri-api/pkg/apis/runtime/v1"
+	tracing "k8s.io/component-base/tracing"
 	podresourcesapi "k8s.io/kubelet/pkg/apis/podresources/v1"
 	podresourcesapiv1alpha1 "k8s.io/kubelet/pkg/apis/podresources/v1alpha1"
 	"k8s.io/kubernetes/pkg/api/legacyscheme"
@@ -127,10 +129,13 @@ type containerInterface interface {
 // so we can ensure restful.FilterFunctions are used for all handlers
 type filteringContainer struct {
 	*restful.Container
+	oteltrace.TracerProvider
+
 	registeredHandlePaths []string
 }
 
 func (a *filteringContainer) Handle(path string, handler http.Handler) {
+	handler = tracing.WithTracing(handler, a.TracerProvider, "kubelet")
 	a.HandleWithFilter(path, handler)
 	a.registeredHandlePaths = append(a.registeredHandlePaths, path)
 }
@@ -144,12 +149,13 @@ func ListenAndServeKubeletServer(
 	resourceAnalyzer stats.ResourceAnalyzer,
 	kubeCfg *kubeletconfiginternal.KubeletConfiguration,
 	tlsOptions *TLSOptions,
-	auth AuthInterface) {
+	auth AuthInterface,
+	tp oteltrace.TracerProvider) {
 
 	address := netutils.ParseIPSloppy(kubeCfg.Address)
 	port := uint(kubeCfg.Port)
 	klog.InfoS("Starting to listen", "address", address, "port", port)
-	handler := NewServer(host, resourceAnalyzer, auth, kubeCfg)
+	handler := NewServer(host, resourceAnalyzer, auth, tp, kubeCfg)
 	s := &http.Server{
 		Addr:           net.JoinHostPort(address.String(), strconv.FormatUint(uint64(port), 10)),
 		Handler:        &handler,
@@ -158,6 +164,7 @@ func ListenAndServeKubeletServer(
 		WriteTimeout:   4 * 60 * time.Minute,
 		MaxHeaderBytes: 1 << 20,
 	}
+
 	if tlsOptions != nil {
 		s.TLSConfig = tlsOptions.Config
 		// Passing empty strings as the cert and key files means no
@@ -174,9 +181,14 @@ func ListenAndServeKubeletServer(
 }
 
 // ListenAndServeKubeletReadOnlyServer initializes a server to respond to HTTP network requests on the Kubelet.
-func ListenAndServeKubeletReadOnlyServer(host HostInterface, resourceAnalyzer stats.ResourceAnalyzer, address net.IP, port uint) {
+func ListenAndServeKubeletReadOnlyServer(
+	host HostInterface,
+	resourceAnalyzer stats.ResourceAnalyzer,
+	address net.IP,
+	port uint) {
 	klog.InfoS("Starting to listen read-only", "address", address, "port", port)
-	s := NewServer(host, resourceAnalyzer, nil, nil)
+	// TODO: https://github.com/kubernetes/kubernetes/issues/109829 tracer should use WithPublicEndpoint
+	s := NewServer(host, resourceAnalyzer, nil, oteltrace.NewNoopTracerProvider(), nil)
 
 	server := &http.Server{
 		Addr:           net.JoinHostPort(address.String(), strconv.FormatUint(uint64(port), 10)),
@@ -241,12 +253,15 @@ func NewServer(
 	host HostInterface,
 	resourceAnalyzer stats.ResourceAnalyzer,
 	auth AuthInterface,
+	tp oteltrace.TracerProvider,
 	kubeCfg *kubeletconfiginternal.KubeletConfiguration) Server {
+	rc := &filteringContainer{Container: restful.NewContainer(), TracerProvider: tp}
+
 	server := Server{
 		host:                 host,
 		resourceAnalyzer:     resourceAnalyzer,
 		auth:                 auth,
-		restfulCont:          &filteringContainer{Container: restful.NewContainer()},
+		restfulCont:          rc,
 		metricsBuckets:       sets.NewString(),
 		metricsMethodBuckets: sets.NewString("OPTIONS", "GET", "HEAD", "POST", "PUT", "DELETE", "TRACE", "CONNECT"),
 	}

pkg/kubelet/server/server_test.go

@@ -37,6 +37,7 @@ import (
 	cadvisorapiv2 "github.com/google/cadvisor/info/v2"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	oteltrace "go.opentelemetry.io/otel/trace"
 	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/types"
@@ -358,6 +359,7 @@ func newServerTestWithDebuggingHandlers(kubeCfg *kubeletconfiginternal.KubeletCo
 		fw.fakeKubelet,
 		stats.NewResourceAnalyzer(fw.fakeKubelet, time.Minute, &record.FakeRecorder{}),
 		fw.fakeAuth,
+		oteltrace.NewNoopTracerProvider(),
 		kubeCfg,
 	)
 	fw.serverUnderTest = &server

staging/src/k8s.io/apiextensions-apiserver/pkg/cmd/server/options/options.go

@@ -23,6 +23,7 @@ import (
 	"net/url"
 
 	"github.com/spf13/pflag"
+	oteltrace "go.opentelemetry.io/otel/trace"
 
 	v1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
 	"k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1beta1"
@@ -111,7 +112,7 @@ func (o CustomResourceDefinitionsServerOptions) Config() (*apiserver.Config, err
 		ExtraConfig: apiserver.ExtraConfig{
 			CRDRESTOptionsGetter: NewCRDRESTOptionsGetter(*o.RecommendedOptions.Etcd),
 			ServiceResolver:      &serviceResolver{serverConfig.SharedInformerFactory.Core().V1().Services().Lister()},
-			AuthResolverWrapper:  webhook.NewDefaultAuthenticationInfoResolverWrapper(nil, nil, serverConfig.LoopbackClientConfig, nil),
+			AuthResolverWrapper:  webhook.NewDefaultAuthenticationInfoResolverWrapper(nil, nil, serverConfig.LoopbackClientConfig, oteltrace.NewNoopTracerProvider()),
 		},
 	}
 	return config, nil

staging/src/k8s.io/apiserver/pkg/endpoints/filters/traces.go

@@ -22,19 +22,17 @@ import (
 	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
 	"go.opentelemetry.io/otel/trace"
 
-	"k8s.io/component-base/traces"
+	tracing "k8s.io/component-base/tracing"
 )
 
 // WithTracing adds tracing to requests if the incoming request is sampled
-func WithTracing(handler http.Handler, tp *trace.TracerProvider) http.Handler {
+func WithTracing(handler http.Handler, tp trace.TracerProvider) http.Handler {
 	opts := []otelhttp.Option{
-		otelhttp.WithPropagators(traces.Propagators()),
+		otelhttp.WithPropagators(tracing.Propagators()),
 		otelhttp.WithPublicEndpoint(),
+		otelhttp.WithTracerProvider(tp),
 	}
-	if tp != nil {
-		opts = append(opts, otelhttp.WithTracerProvider(*tp))
-	}
-	// Even if there is no TracerProvider, the otelhttp still handles context propagation.
+	// With Noop TracerProvider, the otelhttp still handles context propagation.
 	// See https://github.com/open-telemetry/opentelemetry-go/tree/main/example/passthrough
 	return otelhttp.NewHandler(handler, "KubernetesAPI", opts...)
 }

staging/src/k8s.io/apiserver/pkg/server/config.go

@@ -30,7 +30,7 @@ import (
 
 	jsonpatch "github.com/evanphx/json-patch"
 	"github.com/google/uuid"
-	"go.opentelemetry.io/otel/trace"
+	oteltrace "go.opentelemetry.io/otel/trace"
 
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
@@ -139,7 +139,7 @@ type Config struct {
 	ExternalAddress string
 
 	// TracerProvider can provide a tracer, which records spans for distributed tracing.
-	TracerProvider *trace.TracerProvider
+	TracerProvider oteltrace.TracerProvider
 
 	//===========================================================================
 	// Fields you probably don't care about changing
@@ -372,6 +372,7 @@ func NewConfig(codecs serializer.CodecFactory) *Config {
 
 		APIServerID:           id,
 		StorageVersionManager: storageversion.NewDefaultManager(),
+		TracerProvider:        oteltrace.NewNoopTracerProvider(),
 	}
 }
 

staging/src/k8s.io/apiserver/pkg/server/options/coreapi.go

@@ -28,7 +28,7 @@ import (
 	clientgoclientset "k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/clientcmd"
-	"k8s.io/component-base/traces"
+	tracing "k8s.io/component-base/tracing"
 )
 
 // CoreAPIOptions contains options to configure the connection to a core API Kubernetes apiserver.
@@ -73,7 +73,7 @@ func (o *CoreAPIOptions) ApplyTo(config *server.RecommendedConfig) error {
 		}
 	}
 	if feature.DefaultFeatureGate.Enabled(features.APIServerTracing) {
-		kubeconfig.Wrap(traces.WrapperFor(config.TracerProvider))
+		kubeconfig.Wrap(tracing.WrapperFor(config.TracerProvider))
 	}
 	clientgoExternalClient, err := clientgoclientset.NewForConfig(kubeconfig)
 	if err != nil {

staging/src/k8s.io/apiserver/pkg/server/options/recommended.go

@@ -107,10 +107,8 @@ func (o *RecommendedOptions) ApplyTo(config *server.RecommendedConfig) error {
 	if err := o.EgressSelector.ApplyTo(&config.Config); err != nil {
 		return err
 	}
-	if feature.DefaultFeatureGate.Enabled(features.APIServerTracing) {
-		if err := o.Traces.ApplyTo(config.Config.EgressSelector, &config.Config); err != nil {
-			return err
-		}
+	if err := o.Traces.ApplyTo(config.Config.EgressSelector, &config.Config); err != nil {
+		return err
 	}
 	if err := o.SecureServing.ApplyTo(&config.Config.SecureServing, &config.Config.LoopbackClientConfig); err != nil {
 		return err

staging/src/k8s.io/apiserver/pkg/server/options/tracing.go

@@ -19,24 +19,39 @@ package options
 import (
 	"context"
 	"fmt"
+	"io/ioutil"
 	"net"
 
 	"github.com/spf13/pflag"
 	"go.opentelemetry.io/otel/exporters/otlp/otlpgrpc"
 	"go.opentelemetry.io/otel/sdk/resource"
-	sdktrace "go.opentelemetry.io/otel/sdk/trace"
 	"go.opentelemetry.io/otel/semconv"
 	"google.golang.org/grpc"
 
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/serializer"
+	"k8s.io/apiserver/pkg/apis/apiserver"
+	"k8s.io/apiserver/pkg/apis/apiserver/install"
+	"k8s.io/apiserver/pkg/features"
 	"k8s.io/apiserver/pkg/server"
 	"k8s.io/apiserver/pkg/server/egressselector"
-	"k8s.io/apiserver/pkg/tracing"
-	"k8s.io/component-base/traces"
+	"k8s.io/apiserver/pkg/util/feature"
+	tracing "k8s.io/component-base/tracing"
+	tracingapi "k8s.io/component-base/tracing/api/v1"
 	"k8s.io/utils/path"
 )
 
 const apiserverService = "apiserver"
 
+var (
+	cfgScheme = runtime.NewScheme()
+	codecs    = serializer.NewCodecFactory(cfgScheme)
+)
+
+func init() {
+	install.Install(cfgScheme)
+}
+
 // TracingOptions contain configuration options for tracing
 // exporters
 type TracingOptions struct {
@@ -64,21 +79,21 @@ func (o *TracingOptions) ApplyTo(es *egressselector.EgressSelector, c *server.Co
 	if o == nil || o.ConfigFile == "" {
 		return nil
 	}
+	if !feature.DefaultFeatureGate.Enabled(features.APIServerTracing) {
+		return fmt.Errorf("APIServerTracing feature is not enabled, but tracing config file was provided")
+	}
 
-	npConfig, err := tracing.ReadTracingConfiguration(o.ConfigFile)
+	traceConfig, err := ReadTracingConfiguration(o.ConfigFile)
 	if err != nil {
 		return fmt.Errorf("failed to read tracing config: %v", err)
 	}
 
-	errs := tracing.ValidateTracingConfiguration(npConfig)
+	errs := tracingapi.ValidateTracingConfiguration(traceConfig, feature.DefaultFeatureGate, nil)
 	if len(errs) > 0 {
 		return fmt.Errorf("failed to validate tracing configuration: %v", errs.ToAggregate())
 	}
 
 	opts := []otlpgrpc.Option{}
-	if npConfig.Endpoint != nil {
-		opts = append(opts, otlpgrpc.WithEndpoint(*npConfig.Endpoint))
-	}
 	if es != nil {
 		// Only use the egressselector dialer if egressselector is enabled.
 		// Endpoint is on the "ControlPlane" network
@@ -93,21 +108,19 @@ func (o *TracingOptions) ApplyTo(es *egressselector.EgressSelector, c *server.Co
 		opts = append(opts, otlpgrpc.WithDialOption(grpc.WithContextDialer(otelDialer)))
 	}
 
-	sampler := sdktrace.NeverSample()
-	if npConfig.SamplingRatePerMillion != nil && *npConfig.SamplingRatePerMillion > 0 {
-		sampler = sdktrace.TraceIDRatioBased(float64(*npConfig.SamplingRatePerMillion) / float64(1000000))
-	}
-
 	resourceOpts := []resource.Option{
 		resource.WithAttributes(
 			semconv.ServiceNameKey.String(apiserverService),
 			semconv.ServiceInstanceIDKey.String(c.APIServerID),
 		),
 	}
-	tp := traces.NewProvider(context.Background(), sampler, resourceOpts, opts...)
-	c.TracerProvider = &tp
+	tp, err := tracing.NewProvider(context.Background(), traceConfig, opts, resourceOpts)
+	if err != nil {
+		return err
+	}
+	c.TracerProvider = tp
 	if c.LoopbackClientConfig != nil {
-		c.LoopbackClientConfig.Wrap(traces.WrapperFor(c.TracerProvider))
+		c.LoopbackClientConfig.Wrap(tracing.WrapperFor(c.TracerProvider))
 	}
 	return nil
 }
@@ -125,3 +138,24 @@ func (o *TracingOptions) Validate() (errs []error) {
 	}
 	return
 }
+
+// ReadTracingConfiguration reads the tracing configuration from a file
+func ReadTracingConfiguration(configFilePath string) (*tracingapi.TracingConfiguration, error) {
+	if configFilePath == "" {
+		return nil, fmt.Errorf("tracing config file was empty")
+	}
+	data, err := ioutil.ReadFile(configFilePath)
+	if err != nil {
+		return nil, fmt.Errorf("unable to read tracing configuration from %q: %v", configFilePath, err)
+	}
+	internalConfig := &apiserver.TracingConfiguration{}
+	// this handles json/yaml/whatever, and decodes all registered version to the internal version
+	if err := runtime.DecodeInto(codecs.UniversalDecoder(), data, internalConfig); err != nil {
+		return nil, fmt.Errorf("unable to decode tracing configuration data: %v", err)
+	}
+	tc := &tracingapi.TracingConfiguration{
+		Endpoint:               internalConfig.Endpoint,
+		SamplingRatePerMillion: internalConfig.SamplingRatePerMillion,
+	}
+	return tc, nil
+}

staging/src/k8s.io/apiserver/pkg/server/options/tracing_test.go

@@ -16,7 +16,26 @@ limitations under the License.
 
 package options
 
-import "testing"
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"reflect"
+	"strings"
+	"testing"
+
+	tracingapi "k8s.io/component-base/tracing/api/v1"
+)
+
+var (
+	localhost    = "localhost:4317"
+	ipAddress    = "127.0.0.1:4317"
+	samplingRate = int32(12345)
+)
+
+func strptr(s string) *string {
+	return &s
+}
 
 func TestValidateTracingOptions(t *testing.T) {
 	testcases := []struct {
@@ -56,3 +75,110 @@ func TestValidateTracingOptions(t *testing.T) {
 		})
 	}
 }
+
+func TestReadTracingConfiguration(t *testing.T) {
+	testcases := []struct {
+		name           string
+		contents       string
+		createFile     bool
+		expectedResult *tracingapi.TracingConfiguration
+		expectedError  *string
+	}{
+		{
+			name:           "empty",
+			createFile:     true,
+			contents:       ``,
+			expectedResult: &tracingapi.TracingConfiguration{},
+			expectedError:  nil,
+		},
+		{
+			name:           "absent",
+			createFile:     false,
+			contents:       ``,
+			expectedResult: nil,
+			expectedError:  strptr("unable to read tracing configuration from \"test-tracing-config-absent\": open test-tracing-config-absent: no such file or directory"),
+		},
+		{
+			name:       "v1alpha1",
+			createFile: true,
+			contents: `
+apiVersion: apiserver.config.k8s.io/v1alpha1
+kind: TracingConfiguration
+endpoint: localhost:4317
+samplingRatePerMillion: 12345
+`,
+			expectedResult: &tracingapi.TracingConfiguration{
+				Endpoint:               &localhost,
+				SamplingRatePerMillion: &samplingRate,
+			},
+			expectedError: nil,
+		},
+		{
+			name:       "ip address",
+			createFile: true,
+			contents: `
+apiVersion: apiserver.config.k8s.io/v1alpha1
+kind: TracingConfiguration
+endpoint: 127.0.0.1:4317
+`,
+			expectedResult: &tracingapi.TracingConfiguration{
+				Endpoint: &ipAddress,
+			},
+			expectedError: nil,
+		},
+		{
+			name:       "wrong_type",
+			createFile: true,
+			contents: `
+apiVersion: apps/v1
+kind: DaemonSet
+metadata:
+  name: agent
+spec:
+  selector:
+    matchLabels:
+      k8s-app: agent
+  template:
+    metadata:
+      labels:
+        k8s-app: agent
+    spec:
+      containers:
+        - image: k8s.gcr.io/busybox
+          name: agent
+`,
+			expectedResult: nil,
+			expectedError:  strptr("unable to decode tracing configuration data: no kind \"DaemonSet\" is registered for version \"apps/v1\" in scheme"),
+		},
+	}
+
+	for _, tc := range testcases {
+		t.Run(tc.name, func(t *testing.T) {
+			proxyConfig := fmt.Sprintf("test-tracing-config-%s", tc.name)
+			if tc.createFile {
+				f, err := ioutil.TempFile("", proxyConfig)
+				if err != nil {
+					t.Fatal(err)
+				}
+				defer os.Remove(f.Name())
+				if err := ioutil.WriteFile(f.Name(), []byte(tc.contents), os.FileMode(0755)); err != nil {
+					t.Fatal(err)
+				}
+				proxyConfig = f.Name()
+			}
+			config, err := ReadTracingConfiguration(proxyConfig)
+			if err == nil && tc.expectedError != nil {
+				t.Errorf("calling ReadTracingConfiguration expected error: %s, did not get it", *tc.expectedError)
+			}
+			if err != nil && tc.expectedError == nil {
+				t.Errorf("unexpected error calling ReadTracingConfiguration got: %#v", err)
+			}
+			if err != nil && tc.expectedError != nil && !strings.HasPrefix(err.Error(), *tc.expectedError) {
+				t.Errorf("calling ReadTracingConfiguration expected error: %s, got %#v", *tc.expectedError, err)
+			}
+			if !reflect.DeepEqual(config, tc.expectedResult) {
+				t.Errorf("problem with configuration returned from ReadTracingConfiguration expected: %#v, got: %#v", tc.expectedResult, config)
+			}
+		})
+	}
+}

staging/src/k8s.io/apiserver/pkg/storage/storagebackend/config.go

@@ -19,7 +19,8 @@ package storagebackend
 import (
 	"time"
 
-	"go.opentelemetry.io/otel/trace"
+	oteltrace "go.opentelemetry.io/otel/trace"
+
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apiserver/pkg/server/egressselector"
@@ -50,7 +51,7 @@ type TransportConfig struct {
 	// function to determine the egress dialer. (i.e. konnectivity server dialer)
 	EgressLookup egressselector.Lookup
 	// The TracerProvider can add tracing the connection
-	TracerProvider *trace.TracerProvider
+	TracerProvider oteltrace.TracerProvider
 }
 
 // Config is configuration for creating a storage backend.
@@ -122,5 +123,6 @@ func NewDefaultConfig(prefix string, codec runtime.Codec) *Config {
 		HealthcheckTimeout:   DefaultHealthcheckTimeout,
 		ReadycheckTimeout:    DefaultReadinessTimeout,
 		LeaseManagerConfig:   etcd3.NewDefaultLeaseManagerConfig(),
+		Transport:            TransportConfig{TracerProvider: oteltrace.NewNoopTracerProvider()},
 	}
 }

staging/src/k8s.io/apiserver/pkg/storage/storagebackend/factory/etcd3.go

@@ -45,7 +45,7 @@ import (
 	"k8s.io/apiserver/pkg/storage/value"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/component-base/metrics/legacyregistry"
-	"k8s.io/component-base/traces"
+	tracing "k8s.io/component-base/tracing"
 	"k8s.io/klog/v2"
 )
 
@@ -191,12 +191,10 @@ var newETCD3Client = func(c storagebackend.TransportConfig) (*clientv3.Client, e
 	}
 	if utilfeature.DefaultFeatureGate.Enabled(genericfeatures.APIServerTracing) {
 		tracingOpts := []otelgrpc.Option{
-			otelgrpc.WithPropagators(traces.Propagators()),
+			otelgrpc.WithPropagators(tracing.Propagators()),
+			otelgrpc.WithTracerProvider(c.TracerProvider),
 		}
-		if c.TracerProvider != nil {
-			tracingOpts = append(tracingOpts, otelgrpc.WithTracerProvider(*c.TracerProvider))
-		}
-		// Even if there is no TracerProvider, the otelgrpc still handles context propagation.
+		// Even with Noop  TracerProvider, the otelgrpc still handles context propagation.
 		// See https://github.com/open-telemetry/opentelemetry-go/tree/main/example/passthrough
 		dialOptions = append(dialOptions,
 			grpc.WithUnaryInterceptor(otelgrpc.UnaryClientInterceptor(tracingOpts...)),

staging/src/k8s.io/apiserver/pkg/storage/storagebackend/factory/tls_test.go

@@ -25,6 +25,7 @@ import (
 	"testing"
 
 	"go.etcd.io/etcd/client/pkg/v3/transport"
+	oteltrace "go.opentelemetry.io/otel/trace"
 
 	apitesting "k8s.io/apimachinery/pkg/api/apitesting"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -72,10 +73,11 @@ func TestTLSConnection(t *testing.T) {
 	cfg := storagebackend.Config{
 		Type: storagebackend.StorageTypeETCD3,
 		Transport: storagebackend.TransportConfig{
-			ServerList:    client.Endpoints(),
-			CertFile:      certFile,
-			KeyFile:       keyFile,
-			TrustedCAFile: caFile,
+			ServerList:     client.Endpoints(),
+			CertFile:       certFile,
+			KeyFile:        keyFile,
+			TrustedCAFile:  caFile,
+			TracerProvider: oteltrace.NewNoopTracerProvider(),
 		},
 		Codec: codec,
 	}

staging/src/k8s.io/apiserver/pkg/tracing/config_test.go

@@ -1,270 +0,0 @@
-/*
-Copyright 2021 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 tracing
-
-import (
-	"fmt"
-	"io/ioutil"
-	"os"
-	"reflect"
-	"strings"
-	"testing"
-
-	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/apiserver/pkg/apis/apiserver"
-)
-
-var (
-	localhost    = "localhost:4317"
-	ipAddress    = "127.0.0.1:4317"
-	samplingRate = int32(12345)
-)
-
-func strptr(s string) *string {
-	return &s
-}
-
-func TestReadTracingConfiguration(t *testing.T) {
-	testcases := []struct {
-		name           string
-		contents       string
-		createFile     bool
-		expectedResult *apiserver.TracingConfiguration
-		expectedError  *string
-	}{
-		{
-			name:           "empty",
-			createFile:     true,
-			contents:       ``,
-			expectedResult: &apiserver.TracingConfiguration{},
-			expectedError:  nil,
-		},
-		{
-			name:           "absent",
-			createFile:     false,
-			contents:       ``,
-			expectedResult: nil,
-			expectedError:  strptr("unable to read tracing configuration from \"test-tracing-config-absent\": open test-tracing-config-absent: no such file or directory"),
-		},
-		{
-			name:       "v1alpha1",
-			createFile: true,
-			contents: `
-apiVersion: apiserver.config.k8s.io/v1alpha1
-kind: TracingConfiguration
-endpoint: localhost:4317
-samplingRatePerMillion: 12345
-`,
-			expectedResult: &apiserver.TracingConfiguration{
-				TypeMeta: metav1.TypeMeta{
-					Kind:       "",
-					APIVersion: "",
-				},
-				Endpoint:               &localhost,
-				SamplingRatePerMillion: &samplingRate,
-			},
-			expectedError: nil,
-		},
-		{
-			name:       "ip address",
-			createFile: true,
-			contents: `
-apiVersion: apiserver.config.k8s.io/v1alpha1
-kind: TracingConfiguration
-endpoint: 127.0.0.1:4317
-`,
-			expectedResult: &apiserver.TracingConfiguration{
-				TypeMeta: metav1.TypeMeta{
-					Kind:       "",
-					APIVersion: "",
-				},
-				Endpoint: &ipAddress,
-			},
-			expectedError: nil,
-		},
-		{
-			name:       "wrong_type",
-			createFile: true,
-			contents: `
-apiVersion: apps/v1
-kind: DaemonSet
-metadata:
-  name: agent
-spec:
-  selector:
-    matchLabels:
-      k8s-app: agent
-  template:
-    metadata:
-      labels:
-        k8s-app: agent
-    spec:
-      containers:
-        - image: registry.k8s.io/busybox
-          name: agent
-`,
-			expectedResult: nil,
-			expectedError:  strptr("unable to decode tracing configuration data: no kind \"DaemonSet\" is registered for version \"apps/v1\" in scheme"),
-		},
-	}
-
-	for _, tc := range testcases {
-		t.Run(tc.name, func(t *testing.T) {
-			proxyConfig := fmt.Sprintf("test-tracing-config-%s", tc.name)
-			if tc.createFile {
-				f, err := ioutil.TempFile("", proxyConfig)
-				if err != nil {
-					t.Fatal(err)
-				}
-				defer os.Remove(f.Name())
-				if err := ioutil.WriteFile(f.Name(), []byte(tc.contents), os.FileMode(0755)); err != nil {
-					t.Fatal(err)
-				}
-				proxyConfig = f.Name()
-			}
-			config, err := ReadTracingConfiguration(proxyConfig)
-			if err == nil && tc.expectedError != nil {
-				t.Errorf("calling ReadTracingConfiguration expected error: %s, did not get it", *tc.expectedError)
-			}
-			if err != nil && tc.expectedError == nil {
-				t.Errorf("unexpected error calling ReadTracingConfiguration got: %#v", err)
-			}
-			if err != nil && tc.expectedError != nil && !strings.HasPrefix(err.Error(), *tc.expectedError) {
-				t.Errorf("calling ReadTracingConfiguration expected error: %s, got %#v", *tc.expectedError, err)
-			}
-			if !reflect.DeepEqual(config, tc.expectedResult) {
-				t.Errorf("problem with configuration returned from ReadTracingConfiguration expected: %#v, got: %#v", tc.expectedResult, config)
-			}
-		})
-	}
-}
-
-func TestValidateTracingConfiguration(t *testing.T) {
-	samplingRate := int32(12378)
-	negativeRate := int32(-1)
-	tooHighRate := int32(1000001)
-	validEndpoint := "localhost:4317"
-	dnsEndpoint := "dns://google.com:4317"
-	unixEndpoint := "unix://path/to/socket"
-	invalidURL := "dn%2s://localhost:4317"
-	httpEndpoint := "http://localhost:4317"
-	testcases := []struct {
-		name        string
-		expectError bool
-		contents    *apiserver.TracingConfiguration
-	}{
-		{
-			name:        "sampling-rate-valid",
-			expectError: false,
-			contents: &apiserver.TracingConfiguration{
-				TypeMeta: metav1.TypeMeta{
-					Kind:       "",
-					APIVersion: "",
-				},
-				SamplingRatePerMillion: &samplingRate,
-			},
-		},
-		{
-			name:        "sampling-rate-negative",
-			expectError: true,
-			contents: &apiserver.TracingConfiguration{
-				TypeMeta: metav1.TypeMeta{
-					Kind:       "",
-					APIVersion: "",
-				},
-				SamplingRatePerMillion: &negativeRate,
-			},
-		},
-		{
-			name:        "sampling-rate-negative",
-			expectError: true,
-			contents: &apiserver.TracingConfiguration{
-				TypeMeta: metav1.TypeMeta{
-					Kind:       "",
-					APIVersion: "",
-				},
-				SamplingRatePerMillion: &tooHighRate,
-			},
-		},
-		{
-			name:        "default Endpoint",
-			expectError: false,
-			contents: &apiserver.TracingConfiguration{
-				TypeMeta: metav1.TypeMeta{
-					Kind:       "",
-					APIVersion: "",
-				},
-				Endpoint: &validEndpoint,
-			},
-		},
-		{
-			name:        "dns Endpoint",
-			expectError: false,
-			contents: &apiserver.TracingConfiguration{
-				TypeMeta: metav1.TypeMeta{
-					Kind:       "",
-					APIVersion: "",
-				},
-				Endpoint: &dnsEndpoint,
-			},
-		},
-		{
-			name:        "unix Endpoint",
-			expectError: false,
-			contents: &apiserver.TracingConfiguration{
-				TypeMeta: metav1.TypeMeta{
-					Kind:       "",
-					APIVersion: "",
-				},
-				Endpoint: &unixEndpoint,
-			},
-		},
-		{
-			name:        "invalid Endpoint",
-			expectError: true,
-			contents: &apiserver.TracingConfiguration{
-				TypeMeta: metav1.TypeMeta{
-					Kind:       "",
-					APIVersion: "",
-				},
-				Endpoint: &httpEndpoint,
-			},
-		},
-		{
-			name:        "invalid url",
-			expectError: true,
-			contents: &apiserver.TracingConfiguration{
-				TypeMeta: metav1.TypeMeta{
-					Kind:       "",
-					APIVersion: "",
-				},
-				Endpoint: &invalidURL,
-			},
-		},
-	}
-
-	for _, tc := range testcases {
-		t.Run(tc.name, func(t *testing.T) {
-			errs := ValidateTracingConfiguration(tc.contents)
-			if tc.expectError == false && len(errs) != 0 {
-				t.Errorf("Calling ValidateTracingConfiguration expected no error, got %v", errs)
-			} else if tc.expectError == true && len(errs) == 0 {
-				t.Errorf("Calling ValidateTracingConfiguration expected error, got no error")
-			}
-		})
-	}
-}

staging/src/k8s.io/apiserver/pkg/util/webhook/authentication.go

@@ -35,7 +35,7 @@ import (
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/clientcmd"
 	clientcmdapi "k8s.io/client-go/tools/clientcmd/api"
-	"k8s.io/component-base/traces"
+	tracing "k8s.io/component-base/tracing"
 )
 
 // AuthenticationInfoResolverWrapper can be used to inject Dial function to the
@@ -47,7 +47,7 @@ func NewDefaultAuthenticationInfoResolverWrapper(
 	proxyTransport *http.Transport,
 	egressSelector *egressselector.EgressSelector,
 	kubeapiserverClientConfig *rest.Config,
-	tp *trace.TracerProvider) AuthenticationInfoResolverWrapper {
+	tp trace.TracerProvider) AuthenticationInfoResolverWrapper {
 
 	webhookAuthResolverWrapper := func(delegate AuthenticationInfoResolver) AuthenticationInfoResolver {
 		return &AuthenticationInfoResolverDelegator{
@@ -60,7 +60,7 @@ func NewDefaultAuthenticationInfoResolverWrapper(
 					return nil, err
 				}
 				if feature.DefaultFeatureGate.Enabled(features.APIServerTracing) {
-					ret.Wrap(traces.WrapperFor(tp))
+					ret.Wrap(tracing.WrapperFor(tp))
 				}
 
 				if egressSelector != nil {
@@ -85,7 +85,7 @@ func NewDefaultAuthenticationInfoResolverWrapper(
 					return nil, err
 				}
 				if feature.DefaultFeatureGate.Enabled(features.APIServerTracing) {
-					ret.Wrap(traces.WrapperFor(tp))
+					ret.Wrap(tracing.WrapperFor(tp))
 				}
 
 				if egressSelector != nil {

staging/src/k8s.io/component-base/traces/utils.go

@@ -1,81 +0,0 @@
-/*
-Copyright 2021 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 traces
-
-import (
-	"context"
-	"net/http"
-
-	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
-	"go.opentelemetry.io/otel/exporters/otlp"
-	"go.opentelemetry.io/otel/exporters/otlp/otlpgrpc"
-	"go.opentelemetry.io/otel/propagation"
-	"go.opentelemetry.io/otel/sdk/resource"
-	sdktrace "go.opentelemetry.io/otel/sdk/trace"
-	"go.opentelemetry.io/otel/trace"
-
-	"k8s.io/client-go/transport"
-	"k8s.io/klog/v2"
-)
-
-// NewProvider initializes tracing in the component, and enforces recommended tracing behavior.
-func NewProvider(ctx context.Context, baseSampler sdktrace.Sampler, resourceOpts []resource.Option, opts ...otlpgrpc.Option) trace.TracerProvider {
-	opts = append(opts, otlpgrpc.WithInsecure())
-	driver := otlpgrpc.NewDriver(opts...)
-	exporter, err := otlp.NewExporter(ctx, driver)
-	if err != nil {
-		klog.Fatalf("Failed to create OTLP exporter: %v", err)
-	}
-
-	res, err := resource.New(ctx, resourceOpts...)
-	if err != nil {
-		klog.Fatalf("Failed to create resource: %v", err)
-	}
-
-	bsp := sdktrace.NewBatchSpanProcessor(exporter)
-
-	return sdktrace.NewTracerProvider(
-		sdktrace.WithSampler(sdktrace.ParentBased(baseSampler)),
-		sdktrace.WithSpanProcessor(bsp),
-		sdktrace.WithResource(res),
-	)
-}
-
-// WrapperFor can be used to add tracing to a *rest.Config. Example usage:
-//
-//	tp := traces.NewProvider(...)
-//	config, _ := rest.InClusterConfig()
-//	config.Wrap(traces.WrapperFor(&tp))
-//	kubeclient, _ := clientset.NewForConfig(config)
-func WrapperFor(tp *trace.TracerProvider) transport.WrapperFunc {
-	return func(rt http.RoundTripper) http.RoundTripper {
-		opts := []otelhttp.Option{
-			otelhttp.WithPropagators(Propagators()),
-		}
-		if tp != nil {
-			opts = append(opts, otelhttp.WithTracerProvider(*tp))
-		}
-		// Even if there is no TracerProvider, the otelhttp still handles context propagation.
-		// See https://github.com/open-telemetry/opentelemetry-go/tree/main/example/passthrough
-		return otelhttp.NewTransport(rt, opts...)
-	}
-}
-
-// Propagators returns the recommended set of propagators.
-func Propagators() propagation.TextMapPropagator {
-	return propagation.NewCompositeTextMapPropagator(propagation.TraceContext{}, propagation.Baggage{})
-}

staging/src/k8s.io/component-base/tracing/api/OWNERS

@@ -0,0 +1,8 @@
+# See the OWNERS docs at https://go.k8s.io/owners
+
+approvers:
+  - sig-instrumentation-approvers
+reviewers:
+  - sig-instrumentation-reviewers
+labels:
+  - sig/instrumentation

staging/src/k8s.io/component-base/tracing/api/v1/config.go

@@ -14,63 +14,32 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package tracing
+package v1
 
 import (
 	"fmt"
-	"io/ioutil"
 	"net/url"
 	"strings"
 
-	"k8s.io/apimachinery/pkg/runtime"
-	"k8s.io/apimachinery/pkg/runtime/serializer"
 	"k8s.io/apimachinery/pkg/util/validation/field"
-	"k8s.io/apiserver/pkg/apis/apiserver"
-	"k8s.io/apiserver/pkg/apis/apiserver/install"
-)
-
-const (
-	maxSamplingRatePerMillion = 1000000
+	"k8s.io/component-base/featuregate"
 )
 
 var (
-	cfgScheme = runtime.NewScheme()
-	codecs    = serializer.NewCodecFactory(cfgScheme)
+	maxSamplingRatePerMillion = int32(1000000)
 )
 
-func init() {
-	install.Install(cfgScheme)
-}
-
-// ReadTracingConfiguration reads the tracing configuration from a file
-func ReadTracingConfiguration(configFilePath string) (*apiserver.TracingConfiguration, error) {
-	if configFilePath == "" {
-		return nil, fmt.Errorf("tracing config file was empty")
-	}
-	data, err := ioutil.ReadFile(configFilePath)
-	if err != nil {
-		return nil, fmt.Errorf("unable to read tracing configuration from %q: %v", configFilePath, err)
-	}
-	internalConfig := &apiserver.TracingConfiguration{}
-	// this handles json/yaml/whatever, and decodes all registered version to the internal version
-	if err := runtime.DecodeInto(codecs.UniversalDecoder(), data, internalConfig); err != nil {
-		return nil, fmt.Errorf("unable to decode tracing configuration data: %v", err)
-	}
-	return internalConfig, nil
-}
-
 // ValidateTracingConfiguration validates the tracing configuration
-func ValidateTracingConfiguration(config *apiserver.TracingConfiguration) field.ErrorList {
+func ValidateTracingConfiguration(traceConfig *TracingConfiguration, featureGate featuregate.FeatureGate, fldPath *field.Path) field.ErrorList {
 	allErrs := field.ErrorList{}
-	if config == nil {
-		// Tracing is disabled
+	if traceConfig == nil {
 		return allErrs
 	}
-	if config.SamplingRatePerMillion != nil {
-		allErrs = append(allErrs, validateSamplingRate(*config.SamplingRatePerMillion, field.NewPath("samplingRatePerMillion"))...)
+	if traceConfig.SamplingRatePerMillion != nil {
+		allErrs = append(allErrs, validateSamplingRate(*traceConfig.SamplingRatePerMillion, fldPath.Child("samplingRatePerMillion"))...)
 	}
-	if config.Endpoint != nil {
-		allErrs = append(allErrs, validateEndpoint(*config.Endpoint, field.NewPath("endpoint"))...)
+	if traceConfig.Endpoint != nil {
+		allErrs = append(allErrs, validateEndpoint(*traceConfig.Endpoint, fldPath.Child("endpoint"))...)
 	}
 	return allErrs
 }

staging/src/k8s.io/component-base/tracing/api/v1/config_test.go

@@ -0,0 +1,107 @@
+/*
+Copyright 2021 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 v1
+
+import (
+	"testing"
+
+	"k8s.io/apimachinery/pkg/util/validation/field"
+)
+
+func TestValidateTracingConfiguration(t *testing.T) {
+	samplingRate := int32(12378)
+	negativeRate := int32(-1)
+	tooHighRate := int32(1000001)
+	validEndpoint := "localhost:4317"
+	dnsEndpoint := "dns://google.com:4317"
+	unixEndpoint := "unix://path/to/socket"
+	invalidURL := "dn%2s://localhost:4317"
+	httpEndpoint := "http://localhost:4317"
+	testcases := []struct {
+		name        string
+		expectError bool
+		contents    *TracingConfiguration
+	}{
+		{
+			name:        "sampling-rate-valid",
+			expectError: false,
+			contents: &TracingConfiguration{
+				SamplingRatePerMillion: &samplingRate,
+			},
+		},
+		{
+			name:        "sampling-rate-negative",
+			expectError: true,
+			contents: &TracingConfiguration{
+				SamplingRatePerMillion: &negativeRate,
+			},
+		},
+		{
+			name:        "sampling-rate-negative",
+			expectError: true,
+			contents: &TracingConfiguration{
+				SamplingRatePerMillion: &tooHighRate,
+			},
+		},
+		{
+			name:        "default Endpoint",
+			expectError: false,
+			contents: &TracingConfiguration{
+				Endpoint: &validEndpoint,
+			},
+		},
+		{
+			name:        "dns Endpoint",
+			expectError: false,
+			contents: &TracingConfiguration{
+				Endpoint: &dnsEndpoint,
+			},
+		},
+		{
+			name:        "unix Endpoint",
+			expectError: false,
+			contents: &TracingConfiguration{
+				Endpoint: &unixEndpoint,
+			},
+		},
+		{
+			name:        "invalid Endpoint",
+			expectError: true,
+			contents: &TracingConfiguration{
+				Endpoint: &httpEndpoint,
+			},
+		},
+		{
+			name:        "invalid url",
+			expectError: true,
+			contents: &TracingConfiguration{
+				Endpoint: &invalidURL,
+			},
+		},
+	}
+
+	for _, tc := range testcases {
+		t.Run(tc.name, func(t *testing.T) {
+			errs := ValidateTracingConfiguration(tc.contents, nil, field.NewPath("tracing"))
+			if tc.expectError == false && len(errs) != 0 {
+				t.Errorf("Calling ValidateTracingConfiguration expected no error, got %v", errs)
+			} else if tc.expectError == true && len(errs) == 0 {
+				t.Errorf("Calling ValidateTracingConfiguration expected error, got no error")
+			}
+		})
+	}
+}

staging/src/k8s.io/component-base/tracing/api/v1/doc.go

@@ -0,0 +1,29 @@
+/*
+Copyright 2022 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.
+*/
+
+// +k8s:deepcopy-gen=package
+
+// Package v1 contains the configuration API for tracing.
+//
+// The intention is to only have a single version of this API, potentially with
+// new fields added over time in a backwards-compatible manner. Fields for
+// alpha or beta features are allowed as long as they are defined so that not
+// changing the defaults leaves those features disabled.
+//
+// The "v1" package name is just a reminder that API compatibility rules apply,
+// not an indication of the stability of all features covered by it.
+
+package v1 // import "k8s.io/component-base/tracing/api/v1"

staging/src/k8s.io/component-base/tracing/api/v1/types.go

@@ -0,0 +1,32 @@
+/*
+Copyright 2018 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 v1
+
+// TracingConfiguration provides versioned configuration for OpenTelemetry tracing clients.
+type TracingConfiguration struct {
+	// Endpoint of the collector this component will report traces to.
+	// The connection is insecure, and does not currently support TLS.
+	// Recommended is unset, and endpoint is the otlp grpc default, localhost:4317.
+	// +optional
+	Endpoint *string `json:"endpoint,omitempty"`
+
+	// SamplingRatePerMillion is the number of samples to collect per million spans.
+	// Recommended is unset. If unset, sampler respects its parent span's sampling
+	// rate, but otherwise never samples.
+	// +optional
+	SamplingRatePerMillion *int32 `json:"samplingRatePerMillion,omitempty"`
+}

staging/src/k8s.io/component-base/tracing/utils.go

@@ -0,0 +1,108 @@
+/*
+Copyright 2021 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 tracing
+
+import (
+	"context"
+	"net/http"
+
+	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
+	"go.opentelemetry.io/otel/exporters/otlp"
+	"go.opentelemetry.io/otel/exporters/otlp/otlpgrpc"
+	"go.opentelemetry.io/otel/propagation"
+	"go.opentelemetry.io/otel/sdk/resource"
+	sdktrace "go.opentelemetry.io/otel/sdk/trace"
+	oteltrace "go.opentelemetry.io/otel/trace"
+
+	"k8s.io/client-go/transport"
+	"k8s.io/component-base/tracing/api/v1"
+)
+
+// NewProvider creates a TracerProvider in a component, and enforces recommended tracing behavior
+func NewProvider(ctx context.Context,
+	tracingConfig *v1.TracingConfiguration,
+	addedOpts []otlpgrpc.Option,
+	resourceOpts []resource.Option,
+) (oteltrace.TracerProvider, error) {
+	if tracingConfig == nil {
+		return oteltrace.NewNoopTracerProvider(), nil
+	}
+	opts := append([]otlpgrpc.Option{}, addedOpts...)
+	if tracingConfig.Endpoint != nil {
+		opts = append(opts, otlpgrpc.WithEndpoint(*tracingConfig.Endpoint))
+	}
+	opts = append(opts, otlpgrpc.WithInsecure())
+	driver := otlpgrpc.NewDriver(opts...)
+	exporter, err := otlp.NewExporter(ctx, driver)
+	if err != nil {
+		return nil, err
+	}
+	res, err := resource.New(ctx, resourceOpts...)
+	if err != nil {
+		return nil, err
+	}
+
+	// sampler respects parent span's sampling rate or
+	// otherwise never samples.
+	sampler := sdktrace.NeverSample()
+	// Or, emit spans for a fraction of transactions
+	if tracingConfig.SamplingRatePerMillion != nil && *tracingConfig.SamplingRatePerMillion > 0 {
+		sampler = sdktrace.TraceIDRatioBased(float64(*tracingConfig.SamplingRatePerMillion) / float64(1000000))
+	}
+	// batch span processor to aggregate spans before export.
+	bsp := sdktrace.NewBatchSpanProcessor(exporter)
+	tp := sdktrace.NewTracerProvider(
+		sdktrace.WithSampler(sdktrace.ParentBased(sampler)),
+		sdktrace.WithSpanProcessor(bsp),
+		sdktrace.WithResource(res),
+	)
+	return tp, nil
+}
+
+// WithTracing adds tracing to requests if the incoming request is sampled
+func WithTracing(handler http.Handler, tp oteltrace.TracerProvider, serviceName string) http.Handler {
+	opts := []otelhttp.Option{
+		otelhttp.WithPropagators(Propagators()),
+		otelhttp.WithTracerProvider(tp),
+	}
+	// With Noop TracerProvider, the otelhttp still handles context propagation.
+	// See https://github.com/open-telemetry/opentelemetry-go/tree/main/example/passthrough
+	return otelhttp.NewHandler(handler, serviceName, opts...)
+}
+
+// WrapperFor can be used to add tracing to a *rest.Config.
+// Example usage:
+// tp := NewProvider(...)
+// config, _ := rest.InClusterConfig()
+// config.Wrap(WrapperFor(&tp))
+// kubeclient, _ := clientset.NewForConfig(config)
+func WrapperFor(tp oteltrace.TracerProvider) transport.WrapperFunc {
+	return func(rt http.RoundTripper) http.RoundTripper {
+		opts := []otelhttp.Option{
+			otelhttp.WithPropagators(Propagators()),
+			otelhttp.WithTracerProvider(tp),
+		}
+		// With Noop TracerProvider, the otelhttp still handles context propagation.
+		// See https://github.com/open-telemetry/opentelemetry-go/tree/main/example/passthrough
+		return otelhttp.NewTransport(rt, opts...)
+	}
+}
+
+// Propagators returns the recommended set of propagators.
+func Propagators() propagation.TextMapPropagator {
+	return propagation.NewCompositeTextMapPropagator(propagation.TraceContext{}, propagation.Baggage{})
+}

staging/src/k8s.io/kubelet/config/v1beta1/types.go

@@ -20,6 +20,7 @@ import (
 	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	logsapi "k8s.io/component-base/logs/api/v1"
+	tracingapi "k8s.io/component-base/tracing/api/v1"
 )
 
 // HairpinMode denotes how the kubelet should configure networking to handle
@@ -780,6 +781,11 @@ type KubeletConfiguration struct {
 	// Default: true
 	// +optional
 	RegisterNode *bool `json:"registerNode,omitempty"`
+	// Tracing specifies the versioned configuration for OpenTelemetry tracing clients.
+	// See http://kep.k8s.io/2832 for more details.
+	// +featureGate=KubeletTracing
+	// +optional
+	Tracing *tracingapi.TracingConfiguration `json:"tracing,omitempty"`
 }
 
 type KubeletAuthorizationMode string

test/e2e_node/util.go

@@ -31,6 +31,8 @@ import (
 	"strings"
 	"time"
 
+	oteltrace "go.opentelemetry.io/otel/trace"
+
 	v1 "k8s.io/api/core/v1"
 	apiequality "k8s.io/apimachinery/pkg/api/equality"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -298,7 +300,7 @@ func getCRIClient() (internalapi.RuntimeService, internalapi.ImageManagerService
 	// connection timeout for CRI service connection
 	const connectionTimeout = 2 * time.Minute
 	runtimeEndpoint := framework.TestContext.ContainerRuntimeEndpoint
-	r, err := remote.NewRemoteRuntimeService(runtimeEndpoint, connectionTimeout)
+	r, err := remote.NewRemoteRuntimeService(runtimeEndpoint, connectionTimeout, oteltrace.NewNoopTracerProvider())
 	if err != nil {
 		return nil, nil, err
 	}

test/integration/apiserver/tracing/tracing_test.go

@@ -34,7 +34,7 @@ import (
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	client "k8s.io/client-go/kubernetes"
 	featuregatetesting "k8s.io/component-base/featuregate/testing"
-	"k8s.io/component-base/traces"
+	"k8s.io/component-base/tracing"
 	kubeapiservertesting "k8s.io/kubernetes/cmd/kube-apiserver/app/testing"
 	"k8s.io/kubernetes/test/integration/framework"
 )
@@ -84,7 +84,7 @@ endpoint: %s`, listener.Addr().String())), os.FileMode(0755)); err != nil {
 
 	// Create a client that creates sampled traces.
 	tp := trace.TracerProvider(sdktrace.NewTracerProvider(sdktrace.WithSampler(sdktrace.AlwaysSample())))
-	clientConfig.Wrap(traces.WrapperFor(&tp))
+	clientConfig.Wrap(tracing.WrapperFor(tp))
 	clientSet, err := client.NewForConfig(clientConfig)
 	if err != nil {
 		t.Fatal(err)