Enable using protobufs in e2e tests

test/e2e/framework/framework.go

@@ -123,6 +123,9 @@ func (f *Framework) BeforeEach() {
 		Expect(err).NotTo(HaveOccurred())
 		config.QPS = f.options.ClientQPS
 		config.Burst = f.options.ClientBurst
+		if TestContext.KubeAPIContentType != "" {
+			config.ContentType = TestContext.KubeAPIContentType
+		}
 		c, err := loadClientFromConfig(config)
 		Expect(err).NotTo(HaveOccurred())
 		f.Client = c

test/e2e/framework/test_context.go

@@ -28,6 +28,7 @@ import (
 type TestContextType struct {
 	KubeConfig            string
 	KubeContext           string
+	KubeAPIContentType    string
 	KubeVolumeDir         string
 	CertDir               string
 	Host                  string
@@ -90,6 +91,7 @@ func RegisterFlags() {
 
 	flag.StringVar(&TestContext.KubeConfig, clientcmd.RecommendedConfigPathFlag, os.Getenv(clientcmd.RecommendedConfigPathEnvVar), "Path to kubeconfig containing embedded authinfo.")
 	flag.StringVar(&TestContext.KubeContext, clientcmd.FlagContext, "", "kubeconfig context to use/override. If unset, will use value from 'current-context'")
+	flag.StringVar(&TestContext.KubeAPIContentType, "kube-api-content-type", "", "ContentType used to communicate with apiserver")
 	flag.StringVar(&TestContext.KubeVolumeDir, "volume-dir", "/var/lib/kubelet", "Path to the directory containing the kubelet volumes.")
 	flag.StringVar(&TestContext.CertDir, "cert-dir", "", "Path to the directory containing the certs. Default is empty, which doesn't use certs.")
 	flag.StringVar(&TestContext.Host, "host", "", "The host, or apiserver, to connect to")