Refactor controller-manager: turn Serve func into handlerchain builder

cmd/cloud-controller-manager/app/controllermanager.go

@@ -118,12 +118,16 @@ func Run(c *cloudcontrollerconfig.CompletedConfig) error {
 	// Start the controller manager HTTP server
 	stopCh := make(chan struct{})
 	if c.Generic.SecureServing != nil {
-		if err := genericcontrollermanager.Serve(&c.Generic, c.Generic.SecureServing.Serve, stopCh); err != nil {
+		handler := genericcontrollermanager.NewBaseHandler(&c.Generic)
+		handler = genericcontrollermanager.BuildHandlerChain(handler, &c.Generic)
+		if err := c.Generic.SecureServing.Serve(handler, 0, stopCh); err != nil {
 			return err
 		}
 	}
 	if c.Generic.InsecureServing != nil {
-		if err := genericcontrollermanager.Serve(&c.Generic, c.Generic.InsecureServing.Serve, stopCh); err != nil {
+		handler := genericcontrollermanager.NewBaseHandler(&c.Generic)
+		handler = genericcontrollermanager.BuildHandlerChain(handler, &c.Generic)
+		if err := c.Generic.InsecureServing.Serve(handler, 0, stopCh); err != nil {
 			return err
 		}
 	}

cmd/controller-manager/app/serve.go

@@ -19,7 +19,6 @@ package app
 import (
 	"net/http"
 	goruntime "runtime"
-	"time"
 
 	"github.com/prometheus/client_golang/prometheus"
 
@@ -33,11 +32,23 @@ import (
 	"k8s.io/kubernetes/pkg/util/configz"
 )
 
-type serveFunc func(handler http.Handler, shutdownTimeout time.Duration, stopCh <-chan struct{}) error
+// BuildHandlerChain builds a handler chain with a base handler and CompletedConfig.
+func BuildHandlerChain(apiHandler http.Handler, c *CompletedConfig) http.Handler {
+	requestContextMapper := apirequest.NewRequestContextMapper()
+	requestInfoResolver := &apirequest.RequestInfoFactory{}
+	failedHandler := genericapifilters.Unauthorized(requestContextMapper, legacyscheme.Codecs, false)
+
+	handler := genericapifilters.WithAuthorization(apiHandler, requestContextMapper, c.Authorization.Authorizer, legacyscheme.Codecs)
+	handler = genericapifilters.WithAuthentication(handler, requestContextMapper, c.Authentication.Authenticator, failedHandler)
+	handler = genericapifilters.WithRequestInfo(handler, requestInfoResolver, requestContextMapper)
+	handler = apirequest.WithRequestContext(handler, requestContextMapper)
+	handler = genericfilters.WithPanicRecovery(handler)
+
+	return handler
+}
 
-// Serve creates a base handler chain for a controller manager. It runs the
-// the chain with the given serveFunc.
-func Serve(c *CompletedConfig, serveFunc serveFunc, stopCh <-chan struct{}) error {
+// NewBaseHandler takes in CompletedConfig and returns a handler.
+func NewBaseHandler(c *CompletedConfig) http.Handler {
 	mux := mux.NewPathRecorderMux("controller-manager")
 	healthz.InstallHandler(mux)
 	if c.ComponentConfig.EnableProfiling {
@@ -49,15 +60,5 @@ func Serve(c *CompletedConfig, serveFunc serveFunc, stopCh <-chan struct{}) erro
 	configz.InstallHandler(mux)
 	mux.Handle("/metrics", prometheus.Handler())
 
-	requestContextMapper := apirequest.NewRequestContextMapper()
-	requestInfoResolver := &apirequest.RequestInfoFactory{}
-	failedHandler := genericapifilters.Unauthorized(requestContextMapper, legacyscheme.Codecs, false)
-
-	handler := genericapifilters.WithAuthorization(mux, requestContextMapper, c.Authorization.Authorizer, legacyscheme.Codecs)
-	handler = genericapifilters.WithAuthentication(handler, requestContextMapper, c.Authentication.Authenticator, failedHandler)
-	handler = genericapifilters.WithRequestInfo(handler, requestInfoResolver, requestContextMapper)
-	handler = apirequest.WithRequestContext(handler, requestContextMapper)
-	handler = genericfilters.WithPanicRecovery(handler)
-
-	return serveFunc(handler, 0, stopCh)
+	return mux
 }

cmd/kube-controller-manager/app/controllermanager.go

@@ -40,7 +40,7 @@ import (
 	"k8s.io/client-go/tools/leaderelection"
 	"k8s.io/client-go/tools/leaderelection/resourcelock"
 	certutil "k8s.io/client-go/util/cert"
-	genericcontrollerconfig "k8s.io/kubernetes/cmd/controller-manager/app"
+	genericcontrollermanager "k8s.io/kubernetes/cmd/controller-manager/app"
 	"k8s.io/kubernetes/cmd/kube-controller-manager/app/config"
 	"k8s.io/kubernetes/cmd/kube-controller-manager/app/options"
 	"k8s.io/kubernetes/pkg/apis/componentconfig"
@@ -124,12 +124,16 @@ func Run(c *config.CompletedConfig) error {
 	// Start the controller manager HTTP server
 	stopCh := make(chan struct{})
 	if c.Generic.SecureServing != nil {
-		if err := genericcontrollerconfig.Serve(&c.Generic, c.Generic.SecureServing.Serve, stopCh); err != nil {
+		handler := genericcontrollermanager.NewBaseHandler(&c.Generic)
+		handler = genericcontrollermanager.BuildHandlerChain(handler, &c.Generic)
+		if err := c.Generic.SecureServing.Serve(handler, 0, stopCh); err != nil {
 			return err
 		}
 	}
 	if c.Generic.InsecureServing != nil {
-		if err := genericcontrollerconfig.Serve(&c.Generic, c.Generic.InsecureServing.Serve, stopCh); err != nil {
+		handler := genericcontrollermanager.NewBaseHandler(&c.Generic)
+		handler = genericcontrollermanager.BuildHandlerChain(handler, &c.Generic)
+		if err := c.Generic.InsecureServing.Serve(handler, 0, stopCh); err != nil {
 			return err
 		}
 	}
@@ -381,7 +385,7 @@ func CreateControllerContext(s *config.CompletedConfig, rootClientBuilder, clien
 
 	// If apiserver is not running we should wait for some time and fail only then. This is particularly
 	// important when we start apiserver and controller manager at the same time.
-	if err := genericcontrollerconfig.WaitForAPIServer(versionedClient, 10*time.Second); err != nil {
+	if err := genericcontrollermanager.WaitForAPIServer(versionedClient, 10*time.Second); err != nil {
 		return ControllerContext{}, fmt.Errorf("failed to wait for apiserver being healthy: %v", err)
 	}