diff --git a/pkg/util/protoutil/jsonpb_marshal.go b/pkg/util/protoutil/jsonpb_marshal.go
index 5c9317720be1..aec642045a75 100644
--- a/pkg/util/protoutil/jsonpb_marshal.go
+++ b/pkg/util/protoutil/jsonpb_marshal.go
@@ -133,3 +133,8 @@ func (j *JSONPb) NewEncoder(w io.Writer) gwruntime.Encoder {
 		return errors.Errorf("unexpected type %T does not implement %s", v, typeProtoMessage)
 	})
 }
+
+// Delimiter implements gwruntime.Delimited.
+func (*JSONPb) Delimiter() []byte {
+	return []byte("\n")
+}
diff --git a/pkg/util/protoutil/marshaler.go b/pkg/util/protoutil/marshaler.go
index 0f93fba8820f..29f349a9317b 100644
--- a/pkg/util/protoutil/marshaler.go
+++ b/pkg/util/protoutil/marshaler.go
@@ -101,3 +101,8 @@ func (e *protoEncoder) Encode(v interface{}) error {
 	}
 	return errors.Errorf("unexpected type %T does not implement %s", v, typeProtoMessage)
 }
+
+// Delimiter implements gwruntime.Delimited.
+func (*ProtoPb) Delimiter() []byte {
+	return []byte("\n")
+}