DeschedulerServer: new Apply function for applying configuration

cmd/descheduler/app/options/options.go

@@ -22,10 +22,14 @@ import (
 
 	"github.com/spf13/pflag"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	apiserver "k8s.io/apiserver/pkg/server"
 	apiserveroptions "k8s.io/apiserver/pkg/server/options"
 	clientset "k8s.io/client-go/kubernetes"
+	restclient "k8s.io/client-go/rest"
 	componentbaseconfig "k8s.io/component-base/config"
 	componentbaseoptions "k8s.io/component-base/config/options"
+	"k8s.io/klog/v2"
+
 	"sigs.k8s.io/descheduler/pkg/apis/componentconfig"
 	"sigs.k8s.io/descheduler/pkg/apis/componentconfig/v1alpha1"
 	deschedulerscheme "sigs.k8s.io/descheduler/pkg/descheduler/scheme"
@@ -40,11 +44,12 @@ const (
 type DeschedulerServer struct {
 	componentconfig.DeschedulerConfiguration
 
-	Client         clientset.Interface
-	EventClient    clientset.Interface
-	SecureServing  *apiserveroptions.SecureServingOptionsWithLoopback
-	DisableMetrics bool
-	EnableHTTP2    bool
+	Client            clientset.Interface
+	EventClient       clientset.Interface
+	SecureServing     *apiserveroptions.SecureServingOptionsWithLoopback
+	SecureServingInfo *apiserver.SecureServingInfo
+	DisableMetrics    bool
+	EnableHTTP2       bool
 }
 
 // NewDeschedulerServer creates a new DeschedulerServer with default parameters
@@ -107,3 +112,18 @@ func (rs *DeschedulerServer) AddFlags(fs *pflag.FlagSet) {
 
 	rs.SecureServing.AddFlags(fs)
 }
+
+func (rs *DeschedulerServer) Apply() error {
+	// loopbackClientConfig is a config for a privileged loopback connection
+	var loopbackClientConfig *restclient.Config
+	var secureServing *apiserver.SecureServingInfo
+	if err := rs.SecureServing.ApplyTo(&secureServing, &loopbackClientConfig); err != nil {
+		klog.ErrorS(err, "failed to apply secure server configuration")
+		return err
+	}
+
+	secureServing.DisableHTTP2 = !rs.EnableHTTP2
+	rs.SecureServingInfo = secureServing
+
+	return nil
+}

cmd/descheduler/app/server.go

@@ -33,9 +33,7 @@ import (
 
 	"k8s.io/apimachinery/pkg/util/runtime"
 	"k8s.io/apimachinery/pkg/watch"
-	apiserver "k8s.io/apiserver/pkg/server"
 	"k8s.io/apiserver/pkg/server/mux"
-	restclient "k8s.io/client-go/rest"
 	"k8s.io/component-base/featuregate"
 	"k8s.io/component-base/logs"
 	logsapi "k8s.io/component-base/logs/api/v1"
@@ -67,16 +65,11 @@ func NewDeschedulerCommand(out io.Writer) *cobra.Command {
 			return nil
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
-			// loopbackClientConfig is a config for a privileged loopback connection
-			var loopbackClientConfig *restclient.Config
-			var secureServing *apiserver.SecureServingInfo
-			if err := s.SecureServing.ApplyTo(&secureServing, &loopbackClientConfig); err != nil {
-				klog.ErrorS(err, "failed to apply secure server configuration")
+			if err = s.Apply(); err != nil {
+				klog.ErrorS(err, "failed to apply")
 				return err
 			}
 
-			secureServing.DisableHTTP2 = !s.EnableHTTP2
-
 			ctx, done := signal.NotifyContext(cmd.Context(), syscall.SIGINT, syscall.SIGTERM)
 
 			pathRecorderMux := mux.NewPathRecorderMux("descheduler")
@@ -86,7 +79,7 @@ func NewDeschedulerCommand(out io.Writer) *cobra.Command {
 
 			healthz.InstallHandler(pathRecorderMux, healthz.NamedCheck("Descheduler", healthz.PingHealthz.Check))
 
-			stoppedCh, _, err := secureServing.Serve(pathRecorderMux, 0, ctx.Done())
+			stoppedCh, _, err := s.SecureServingInfo.Serve(pathRecorderMux, 0, ctx.Done())
 			if err != nil {
 				klog.Fatalf("failed to start secure server: %v", err)
 				return err