Make generated client codecs support CBOR based on feature gate.

Kubernetes-commit: 57e337dbbf9e437bcb350d6551689669bb79d579

rest/config.go

@@ -32,6 +32,9 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/runtime/serializer"
+	"k8s.io/apimachinery/pkg/runtime/serializer/cbor"
+	"k8s.io/client-go/features"
 	"k8s.io/client-go/pkg/version"
 	clientcmdapi "k8s.io/client-go/tools/clientcmd/api"
 	"k8s.io/client-go/transport"
@@ -672,3 +675,31 @@ func CopyConfig(config *Config) *Config {
 	}
 	return c
 }
+
+// CodecFactoryForGeneratedClient returns the provided CodecFactory if there are no enabled client
+// feature gates affecting serialization. Otherwise, it constructs and returns a new CodecFactory
+// from the provided Scheme.
+//
+// This is supported ONLY for use by clients generated with client-gen. The caller is responsible
+// for ensuring that the CodecFactory argument was constructed using the Scheme argument.
+func CodecFactoryForGeneratedClient(scheme *runtime.Scheme, codecs serializer.CodecFactory) serializer.CodecFactory {
+	if !features.TestOnlyFeatureGates.Enabled(features.TestOnlyClientAllowsCBOR) {
+		// NOTE: This assumes client-gen will not generate CBOR-enabled Codecs as long as
+		// the feature gate exists.
+		return codecs
+	}
+
+	return serializer.NewCodecFactory(scheme, serializer.WithSerializer(func(creater runtime.ObjectCreater, typer runtime.ObjectTyper) runtime.SerializerInfo {
+		return runtime.SerializerInfo{
+			MediaType:        "application/cbor",
+			MediaTypeType:    "application",
+			MediaTypeSubType: "cbor",
+			Serializer:       cbor.NewSerializer(creater, typer),
+			StrictSerializer: cbor.NewSerializer(creater, typer, cbor.Strict(true)),
+			StreamSerializer: &runtime.StreamSerializerInfo{
+				Framer:     cbor.NewFramer(),
+				Serializer: cbor.NewSerializer(creater, typer, cbor.Transcode(false)),
+			},
+		}
+	}))
+}