@Override
  public void writeTo(AsyncWritableChannel channel, Callback<Long> callback) {
    if (bufferToSend == null) {
      prepareBuffer();
    }
    channel.write(bufferToSend, callback);
  }
Request Response for serialization and de-serialization
ambry-protocol/src/main/java/com/github/ambry/protocol/RequestOrResponse.java