Move grpc rate limitter from podresource folder

Rate limitter.go file is a generic file implementing
grpc Limiter interface. This file can be reuse by other gRPC
API not only by podresource.

Change-Id: I905a46b5b605fbb175eb9ad6c15019ffdc7f2563

pkg/kubelet/apis/grpc/ratelimit.go

@@ -27,17 +27,6 @@ import (
 	"google.golang.org/grpc/status"
 )
 
-const (
-	// DefaultQPS is determined by empirically reviewing known consumers of the API.
-	// It's at least unlikely that there is a legitimate need to query podresources
-	// more than 100 times per second, the other subsystems are not guaranteed to react
-	// so fast in the first place.
-	DefaultQPS = 100
-	// DefaultBurstTokens is determined by empirically reviewing known consumers of the API.
-	// See the documentation of DefaultQPS, same caveats apply.
-	DefaultBurstTokens = 10
-)
-
 var (
 	ErrorLimitExceeded = status.Error(codes.ResourceExhausted, "rejected by rate limit")
 )
@@ -59,9 +48,10 @@ func LimiterUnaryServerInterceptor(limiter Limiter) grpc.UnaryServerInterceptor
 	}
 }
 
-func WithRateLimiter(qps, burstTokens int32) grpc.ServerOption {
+// WithRateLimiter creates new rate limiter with unary interceptor.
+func WithRateLimiter(serviceName string, qps, burstTokens int32) grpc.ServerOption {
 	qpsVal := gotimerate.Limit(qps)
 	burstVal := int(burstTokens)
-	klog.InfoS("Setting rate limiting for podresources endpoint", "qps", qpsVal, "burstTokens", burstVal)
+	klog.InfoS("Setting rate limiting for endpoint", "service", serviceName, "qps", qpsVal, "burstTokens", burstVal)
 	return grpc.UnaryInterceptor(LimiterUnaryServerInterceptor(gotimerate.NewLimiter(qpsVal, burstVal)))
 }

pkg/kubelet/apis/podresources/constants.go

@@ -19,4 +19,14 @@ package podresources
 const (
 	// Socket is the name of the podresources server socket
 	Socket = "kubelet"
+
+	// DefaultQPS is determined by empirically reviewing known consumers of the API.
+	// It's at least unlikely that there is a legitimate need to query podresources
+	// more than 100 times per second, the other subsystems are not guaranteed to react
+	// so fast in the first place.
+	DefaultQPS = 100
+
+	// DefaultBurstTokens is determined by empirically reviewing known consumers of the API.
+	// See the documentation of DefaultQPS, same caveats apply.
+	DefaultBurstTokens = 10
 )

pkg/kubelet/server/server.go

@@ -78,8 +78,8 @@ import (
 	"k8s.io/kubernetes/pkg/apis/core/v1/validation"
 	"k8s.io/kubernetes/pkg/features"
 	kubeletconfiginternal "k8s.io/kubernetes/pkg/kubelet/apis/config"
+	apisgrpc "k8s.io/kubernetes/pkg/kubelet/apis/grpc"
 	"k8s.io/kubernetes/pkg/kubelet/apis/podresources"
-	podresourcesgrpc "k8s.io/kubernetes/pkg/kubelet/apis/podresources/grpc"
 	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
 	"k8s.io/kubernetes/pkg/kubelet/prober"
 	servermetrics "k8s.io/kubernetes/pkg/kubelet/server/metrics"
@@ -219,7 +219,7 @@ type PodResourcesProviders struct {
 
 // ListenAndServePodResources initializes a gRPC server to serve the PodResources service
 func ListenAndServePodResources(endpoint string, providers podresources.PodResourcesProviders) {
-	server := grpc.NewServer(podresourcesgrpc.WithRateLimiter(podresourcesgrpc.DefaultQPS, podresourcesgrpc.DefaultBurstTokens))
+	server := grpc.NewServer(apisgrpc.WithRateLimiter("podresources", podresources.DefaultQPS, podresources.DefaultBurstTokens))
 
 	podresourcesapiv1alpha1.RegisterPodResourcesListerServer(server, podresources.NewV1alpha1PodResourcesServer(providers))
 	podresourcesapi.RegisterPodResourcesListerServer(server, podresources.NewV1PodResourcesServer(providers))

test/e2e_node/podresources_test.go

@@ -31,8 +31,8 @@ import (
 	kubeletpodresourcesv1 "k8s.io/kubelet/pkg/apis/podresources/v1"
 	kubefeatures "k8s.io/kubernetes/pkg/features"
 	kubeletconfig "k8s.io/kubernetes/pkg/kubelet/apis/config"
+	apisgrpc "k8s.io/kubernetes/pkg/kubelet/apis/grpc"
 	"k8s.io/kubernetes/pkg/kubelet/apis/podresources"
-	podresourcesgrpc "k8s.io/kubernetes/pkg/kubelet/apis/podresources/grpc"
 	"k8s.io/kubernetes/pkg/kubelet/cm/cpumanager"
 	"k8s.io/kubernetes/pkg/kubelet/util"
 	testutils "k8s.io/kubernetes/test/utils"
@@ -974,7 +974,7 @@ var _ = SIGDescribe("POD Resources [Serial] [Feature:PodResources][NodeFeature:P
 			framework.ExpectNoError(err, "GetV1Client() failed err %v", err)
 			defer conn.Close()
 
-			tries := podresourcesgrpc.DefaultQPS * 2 // This should also be greater than DefaultBurstTokens
+			tries := podresources.DefaultQPS * 2 // This should also be greater than DefaultBurstTokens
 			errs := []error{}
 
 			ginkgo.By(fmt.Sprintf("Issuing %d List() calls in a tight loop", tries))
@@ -994,7 +994,7 @@ var _ = SIGDescribe("POD Resources [Serial] [Feature:PodResources][NodeFeature:P
 			// constraints than to risk flakes at this stage.
 			errLimitExceededCount := 0
 			for _, err := range errs[1:] {
-				if errors.Is(err, podresourcesgrpc.ErrorLimitExceeded) {
+				if errors.Is(err, apisgrpc.ErrorLimitExceeded) {
 					errLimitExceededCount++
 				}
 			}