private void SerializeRequest(IMethodCallMessage methodCall, out ITransportHeaders requestHeaders, out Stream requestStream)
{
// get request stream
requestHeaders = new TransportHeaders();
requestStream = _nextSink.GetRequestStream(methodCall, requestHeaders);
if (requestStream == null)
{
requestStream = new ChunkedMemoryStream();
}
// serialize request
_formatter.SerializeRequest(methodCall, requestHeaders, requestStream);
}