Ignore changes to creation timestamp from clients on update

pkg/api/validation/validation.go

@@ -219,7 +219,10 @@ func ValidateObjectMetaUpdate(old, meta *api.ObjectMeta) errs.ValidationErrorLis
 	if len(meta.UID) == 0 {
 		meta.UID = old.UID
 	}
-	if meta.CreationTimestamp.IsZero() {
+	// ignore changes to timestamp
+	if old.CreationTimestamp.IsZero() {
+		old.CreationTimestamp = meta.CreationTimestamp
+	} else {
 		meta.CreationTimestamp = old.CreationTimestamp
 	}
 

pkg/api/validation/validation_test.go

@@ -19,6 +19,7 @@ package validation
 import (
 	"strings"
 	"testing"
+	"time"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
@@ -53,6 +54,27 @@ func TestValidateObjectMetaCustomName(t *testing.T) {
 	}
 }
 
+func TestValidateObjectMetaUpdateIgnoresCreationTimestamp(t *testing.T) {
+	if errs := ValidateObjectMetaUpdate(
+		&api.ObjectMeta{Name: "test", CreationTimestamp: util.NewTime(time.Unix(10, 0))},
+		&api.ObjectMeta{Name: "test"},
+	); len(errs) != 0 {
+		t.Fatalf("unexpected errors: %v", errs)
+	}
+	if errs := ValidateObjectMetaUpdate(
+		&api.ObjectMeta{Name: "test"},
+		&api.ObjectMeta{Name: "test", CreationTimestamp: util.NewTime(time.Unix(10, 0))},
+	); len(errs) != 0 {
+		t.Fatalf("unexpected errors: %v", errs)
+	}
+	if errs := ValidateObjectMetaUpdate(
+		&api.ObjectMeta{Name: "test", CreationTimestamp: util.NewTime(time.Unix(11, 0))},
+		&api.ObjectMeta{Name: "test", CreationTimestamp: util.NewTime(time.Unix(10, 0))},
+	); len(errs) != 0 {
+		t.Fatalf("unexpected errors: %v", errs)
+	}
+}
+
 // Ensure trailing slash is allowed in generate name
 func TestValidateObjectMetaTrimsTrailingSlash(t *testing.T) {
 	errs := ValidateObjectMeta(&api.ObjectMeta{Name: "test", GenerateName: "foo-"}, false, nameIsDNSSubdomain)