Merge pull request #76659 from S-Chan/stephen_chan--lazy_initialize_signal_handling

Lazily initialize signal handling for hyperkube apiserver and kubelet

cmd/genkubedocs/BUILD

@@ -31,7 +31,6 @@ go_library(
         "//cmd/kube-scheduler/app:go_default_library",
         "//cmd/kubeadm/app/cmd:go_default_library",
         "//cmd/kubelet/app:go_default_library",
-        "//staging/src/k8s.io/apiserver/pkg/server:go_default_library",
         "//vendor/github.com/spf13/cobra:go_default_library",
         "//vendor/github.com/spf13/cobra/doc:go_default_library",
         "//vendor/github.com/spf13/pflag:go_default_library",

cmd/genkubedocs/gen_kube_docs.go

@@ -22,7 +22,6 @@ import (
 
 	"github.com/spf13/cobra/doc"
 	"github.com/spf13/pflag"
-	"k8s.io/apiserver/pkg/server"
 	ccmapp "k8s.io/kubernetes/cmd/cloud-controller-manager/app"
 	"k8s.io/kubernetes/cmd/genutils"
 	apiservapp "k8s.io/kubernetes/cmd/kube-apiserver/app"
@@ -54,7 +53,7 @@ func main() {
 	switch module {
 	case "kube-apiserver":
 		// generate docs for kube-apiserver
-		apiserver := apiservapp.NewAPIServerCommand(server.SetupSignalHandler())
+		apiserver := apiservapp.NewAPIServerCommand()
 		doc.GenMarkdownTree(apiserver, outDir)
 	case "kube-controller-manager":
 		// generate docs for kube-controller-manager
@@ -74,7 +73,7 @@ func main() {
 		doc.GenMarkdownTree(scheduler, outDir)
 	case "kubelet":
 		// generate docs for kubelet
-		kubelet := kubeletapp.NewKubeletCommand(server.SetupSignalHandler())
+		kubelet := kubeletapp.NewKubeletCommand()
 		doc.GenMarkdownTree(kubelet, outDir)
 	case "kubeadm":
 		// resets global flags created by kubelet or other commands e.g.

cmd/genman/BUILD

@@ -25,7 +25,6 @@ go_library(
         "//cmd/kubeadm/app/cmd:go_default_library",
         "//cmd/kubelet/app:go_default_library",
         "//pkg/kubectl/cmd:go_default_library",
-        "//staging/src/k8s.io/apiserver/pkg/server:go_default_library",
         "//vendor/github.com/cpuguy83/go-md2man/md2man:go_default_library",
         "//vendor/github.com/spf13/cobra:go_default_library",
         "//vendor/github.com/spf13/pflag:go_default_library",

cmd/genman/gen_kube_man.go

@@ -26,7 +26,6 @@ import (
 	mangen "github.com/cpuguy83/go-md2man/md2man"
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
-	"k8s.io/apiserver/pkg/server"
 	ccmapp "k8s.io/kubernetes/cmd/cloud-controller-manager/app"
 	"k8s.io/kubernetes/cmd/genutils"
 	apiservapp "k8s.io/kubernetes/cmd/kube-apiserver/app"
@@ -63,7 +62,7 @@ func main() {
 	switch module {
 	case "kube-apiserver":
 		// generate manpage for kube-apiserver
-		apiserver := apiservapp.NewAPIServerCommand(server.SetupSignalHandler())
+		apiserver := apiservapp.NewAPIServerCommand()
 		genMarkdown(apiserver, "", outDir)
 		for _, c := range apiserver.Commands() {
 			genMarkdown(c, "kube-apiserver", outDir)
@@ -98,7 +97,7 @@ func main() {
 		}
 	case "kubelet":
 		// generate manpage for kubelet
-		kubelet := kubeletapp.NewKubeletCommand(server.SetupSignalHandler())
+		kubelet := kubeletapp.NewKubeletCommand()
 		genMarkdown(kubelet, "", outDir)
 		for _, c := range kubelet.Commands() {
 			genMarkdown(c, "kubelet", outDir)

cmd/hyperkube/BUILD

@@ -27,7 +27,6 @@ go_library(
         "//pkg/client/metrics/prometheus:go_default_library",
         "//pkg/kubectl/cmd:go_default_library",
         "//pkg/version/prometheus:go_default_library",
-        "//staging/src/k8s.io/apiserver/pkg/server:go_default_library",
         "//staging/src/k8s.io/component-base/cli/flag:go_default_library",
         "//staging/src/k8s.io/component-base/logs:go_default_library",
         "//vendor/github.com/spf13/cobra:go_default_library",

cmd/hyperkube/main.go

@@ -32,7 +32,6 @@ import (
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
 
-	"k8s.io/apiserver/pkg/server"
 	cliflag "k8s.io/component-base/cli/flag"
 	"k8s.io/component-base/logs"
 	cloudcontrollermanager "k8s.io/kubernetes/cmd/cloud-controller-manager/app"
@@ -49,7 +48,7 @@ import (
 func main() {
 	rand.Seed(time.Now().UnixNano())
 
-	hyperkubeCommand, allCommandFns := NewHyperKubeCommand(server.SetupSignalHandler())
+	hyperkubeCommand, allCommandFns := NewHyperKubeCommand()
 
 	// TODO: once we switch everything over to Cobra commands, we can go back to calling
 	// cliflag.InitFlags() (by removing its pflag.Parse() call). For now, we have to set the
@@ -84,15 +83,15 @@ func commandFor(basename string, defaultCommand *cobra.Command, commands []func(
 }
 
 // NewHyperKubeCommand is the entry point for hyperkube
-func NewHyperKubeCommand(stopCh <-chan struct{}) (*cobra.Command, []func() *cobra.Command) {
+func NewHyperKubeCommand() (*cobra.Command, []func() *cobra.Command) {
 	// these have to be functions since the command is polymorphic. Cobra wants you to be top level
 	// command to get executed
-	apiserver := func() *cobra.Command { return kubeapiserver.NewAPIServerCommand(stopCh) }
+	apiserver := func() *cobra.Command { return kubeapiserver.NewAPIServerCommand() }
 	controller := func() *cobra.Command { return kubecontrollermanager.NewControllerManagerCommand() }
 	proxy := func() *cobra.Command { return kubeproxy.NewProxyCommand() }
 	scheduler := func() *cobra.Command { return kubescheduler.NewSchedulerCommand() }
 	kubectlCmd := func() *cobra.Command { return kubectl.NewDefaultKubectlCommand() }
-	kubelet := func() *cobra.Command { return kubelet.NewKubeletCommand(stopCh) }
+	kubelet := func() *cobra.Command { return kubelet.NewKubeletCommand() }
 	cloudController := func() *cobra.Command { return cloudcontrollermanager.NewCloudControllerManagerCommand() }
 
 	commandFns := []func() *cobra.Command{

cmd/kube-apiserver/BUILD

@@ -22,7 +22,6 @@ go_library(
         "//cmd/kube-apiserver/app:go_default_library",
         "//pkg/util/prometheusclientgo:go_default_library",
         "//pkg/version/prometheus:go_default_library",
-        "//staging/src/k8s.io/apiserver/pkg/server:go_default_library",
         "//staging/src/k8s.io/component-base/logs:go_default_library",
     ],
 )

cmd/kube-apiserver/apiserver.go

@@ -24,7 +24,6 @@ import (
 	"os"
 	"time"
 
-	"k8s.io/apiserver/pkg/server"
 	"k8s.io/component-base/logs"
 	"k8s.io/kubernetes/cmd/kube-apiserver/app"
 	_ "k8s.io/kubernetes/pkg/util/prometheusclientgo" // load all the prometheus client-go plugins
@@ -34,7 +33,7 @@ import (
 func main() {
 	rand.Seed(time.Now().UnixNano())
 
-	command := app.NewAPIServerCommand(server.SetupSignalHandler())
+	command := app.NewAPIServerCommand()
 
 	// TODO: once we switch everything over to Cobra commands, we can go back to calling
 	// utilflag.InitFlags() (by removing its pflag.Parse() call). For now, we have to set the

cmd/kube-apiserver/app/server.go

@@ -88,7 +88,7 @@ const etcdRetryLimit = 60
 const etcdRetryInterval = 1 * time.Second
 
 // NewAPIServerCommand creates a *cobra.Command object with default parameters
-func NewAPIServerCommand(stopCh <-chan struct{}) *cobra.Command {
+func NewAPIServerCommand() *cobra.Command {
 	s := options.NewServerRunOptions()
 	cmd := &cobra.Command{
 		Use: "kube-apiserver",
@@ -111,7 +111,7 @@ cluster's shared state through which all other components interact.`,
 				return utilerrors.NewAggregate(errs)
 			}
 
-			return Run(completedOptions, stopCh)
+			return Run(completedOptions, genericapiserver.SetupSignalHandler())
 		},
 	}
 

cmd/kubelet/BUILD

@@ -21,7 +21,6 @@ go_library(
         "//cmd/kubelet/app:go_default_library",
         "//pkg/client/metrics/prometheus:go_default_library",
         "//pkg/version/prometheus:go_default_library",
-        "//staging/src/k8s.io/apiserver/pkg/server:go_default_library",
         "//staging/src/k8s.io/component-base/logs:go_default_library",
     ],
 )

cmd/kubelet/app/BUILD

@@ -122,6 +122,7 @@ go_library(
         "//staging/src/k8s.io/apiserver/pkg/authentication/authenticatorfactory:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/authorization/authorizer:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/authorization/authorizerfactory:go_default_library",
+        "//staging/src/k8s.io/apiserver/pkg/server:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/server/healthz:go_default_library",
         "//staging/src/k8s.io/apiserver/pkg/util/feature:go_default_library",
         "//staging/src/k8s.io/client-go/kubernetes:go_default_library",

cmd/kubelet/app/server.go

@@ -46,6 +46,7 @@ import (
 	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/wait"
+	genericapiserver "k8s.io/apiserver/pkg/server"
 	"k8s.io/apiserver/pkg/server/healthz"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	clientset "k8s.io/client-go/kubernetes"
@@ -108,7 +109,7 @@ const (
 )
 
 // NewKubeletCommand creates a *cobra.Command object with default parameters
-func NewKubeletCommand(stopCh <-chan struct{}) *cobra.Command {
+func NewKubeletCommand() *cobra.Command {
 	cleanFlagSet := pflag.NewFlagSet(componentKubelet, pflag.ContinueOnError)
 	cleanFlagSet.SetNormalizeFunc(cliflag.WordSepNormalizeFunc)
 	kubeletFlags := options.NewKubeletFlags()
@@ -254,6 +255,9 @@ HTTP server: The kubelet can also listen for HTTP and respond to a simple API
 			// add the kubelet config controller to kubeletDeps
 			kubeletDeps.KubeletConfigController = kubeletConfigController
 
+			// set up stopCh here in order to be reused by kubelet and docker shim
+			stopCh := genericapiserver.SetupSignalHandler()
+
 			// start the experimental docker shim, if enabled
 			if kubeletServer.KubeletFlags.ExperimentalDockershim {
 				if err := RunDockershim(&kubeletServer.KubeletFlags, kubeletConfig, stopCh); err != nil {

cmd/kubelet/kubelet.go

@@ -26,7 +26,6 @@ import (
 	"os"
 	"time"
 
-	"k8s.io/apiserver/pkg/server"
 	"k8s.io/component-base/logs"
 	"k8s.io/kubernetes/cmd/kubelet/app"
 	_ "k8s.io/kubernetes/pkg/client/metrics/prometheus" // for client metric registration
@@ -36,7 +35,7 @@ import (
 func main() {
 	rand.Seed(time.Now().UnixNano())
 
-	command := app.NewKubeletCommand(server.SetupSignalHandler())
+	command := app.NewKubeletCommand()
 	logs.InitLogs()
 	defer logs.FlushLogs()