getProgressFunc func() (int64, int64)
	bytesReturned   int64

	payloadBuffer      []byte
	payloadBufferIndex int
	payloadCh          chan *bytes.Buffer

	finBytesScanned, finBytesProcessed int64

	errCh  chan []byte
	doneCh chan struct{}
}

func (writer *messageWriter) write(data []byte) bool {
	if _, err := writer.writer.Write(data); err != nil {
		return false
	}