Merge pull request #3319 from yuswift/remove_http1.1_support_code

remove http1.1 support code

pkg/apiserver/dispatch/dispatch.go

@@ -26,7 +26,6 @@ import (
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/util/httpstream"
-	"k8s.io/apimachinery/pkg/util/net"
 	"k8s.io/apimachinery/pkg/util/proxy"
 	"k8s.io/apiserver/pkg/endpoints/handlers/responsewriters"
 	"k8s.io/client-go/rest"
@@ -201,21 +200,6 @@ func (c *clusterDispatch) getInnerCluster(name string) *innerCluster {
 	return nil
 }
 
-// copy from https://github.com/kubernetes/apimachinery/blob/master/pkg/util/proxy/dial.go
-func supportsHTTP11(nextProtos []string) bool {
-	if len(nextProtos) == 0 {
-		return true
-	}
-
-	for _, proto := range nextProtos {
-		if proto == "http/1.1" {
-			return true
-		}
-	}
-
-	return false
-}
-
 func (c *clusterDispatch) updateInnerClusters(obj interface{}) {
 	cluster := obj.(*clusterv1alpha1.Cluster)
 
@@ -250,14 +234,6 @@ func (c *clusterDispatch) updateInnerClusters(obj interface{}) {
 		return
 	}
 
-	tlsConfig, err := net.TLSClientConfig(transport)
-	if err == nil {
-		// since http2 doesn't support websocket, we need to disable http2 when using websocket
-		if supportsHTTP11(tlsConfig.NextProtos) {
-			tlsConfig.NextProtos = []string{"http/1.1"}
-		}
-	}
-
 	c.mutex.Lock()
 	c.innerClusters[cluster.Name] = &innerCluster{
 		kubernetesURL: kubernetesEndpoint,