QtWebSocket sending binary data with msgpack to ESP32 mcu

[Kris Revi]

@SGaist

void MainWindow::on_comboBoxSelectStrip_activated(int index)
{
    qDebug() << "[SelectedStrip][Currently] : " << index;
    sendBinary("selectedstrip", index);
}

void MainWindow::sendBinary(QString text, QVariant args)
{
    _MsgPackMap.clear();
    _MsgPackMap.insert(text, args);
    _MsgPackArray = MsgPack::pack(_MsgPackMap);
    _socket.sendBinaryToStrip(_MsgPackArray);
}

void Socket::sendBinaryToStrip(const QByteArray data)
{
    m_webSocket.sendBinaryMessage(data);
    qDebug() << "Binary Data : " << data;
    qDebug() << "Binary Length : " << data.size();
}

[Christian Ehrlicher]

So how long is the binary length with 0 and with 1?
Also what is _MsgPackMap?

[Kris Revi]

@Christian-Ehrlicher

to quote the website of msgpack It's like JSON. but fast and small.

the variable itself is QVariantMap _MsgPackMap;

let me check the length and get back to you!

Edit

selectedStrip = 0

[SelectedStrip][Currently] :  0
Binary Data :  "\x81\xADselectedstrip\x00"
Binary Length :  16

selectedStrip = 1

[SelectedStrip][Currently] :  1
Binary Data :  "\x81\xADselectedstrip\x01"
Binary Length :  16

[Christian Ehrlicher]

Looks like a problem on the receiver side:

int main(int argc, char **argv)
{
  QCoreApplication app(argc, argv);
  QVariantMap  v0, v1;
  v0.insert("selectedstrip", 0);
  v1.insert("selectedstrip", 1);
  qDebug() <<  MsgPack::pack(v0);
  qDebug() <<  MsgPack::pack(v1);
  return 0;
}

-->
"\x81\xADselectedstrip\x00"
"\x81\xADselectedstrip\x01"

[Kris Revi]

@Christian-Ehrlicher

so on the ESP32 side i printed out msgpack unpacked data and the payload from arduinowebsocket and NONE of them prints out anything when "selectedStrip = 0"

            if ( mIndata["selectedstrip"] )
            {
                Serial.print("selectedstrip : ");
                Serial.print((int)mIndata["selectedstrip"]);
                Serial.println(" ");
                Serial.print("Payload : ");
                for ( int i = 0; i < length; i++ )
                    Serial.print(payload[i]);
                Serial.println(" ");

                _selectedStrip = mIndata["selectedstrip"];
            }

selectedstrip : 1
Payload : 129173115101108101991161011001151161141051121 
selectedstrip : 2
Payload : 129173115101108101991161011001151161141051122 
selectedstrip : 3
Payload : 129173115101108101991161011001151161141051123 
selectedstrip : 4
Payload : 129173115101108101991161011001151161141051124 

so i would guess the problem is the arduinowebsocket? or am i wrong?

[Christian Ehrlicher]

@Kris-Revi said in QtWebSocket sending binary data with msgpack to ESP32 mcu:

is the arduinowebsocket?

Looks like - QWebSocket::sendBinaryMessage() works correct I would guess.

[Kris Revi]

@Christian-Ehrlicher as @SGaist said

@SGaist said in QtWebSocket sending binary data with msgpack to ESP32 mcu:

QByteArray is binary data but if you handle its content as string it will be cut at the termination char.

on the ESP32 side i do this

MsgPack::Unpacker unpacker;
MsgPack::map_t<String, int> mIndata;

[Kris Revi]

@Christian-Ehrlicher so i printed the payload inside if ( mIndata["selectedstrip"] ) { } moved it outside of that and got a result on "selectedStrip = 0"

1

selectedstrip : 1 
Payload : 1291731141011136810111810599101731101021111

0

Payload : 129173115101108101991161011001151161141051120

notice that msgpack does not print on 0 only payload

[Christian Ehrlicher]

I don't really know how binary data is encoded in websocket (if at all) but what you can do is to create a simple receiver with Qt websocket to see if it properly arrives there and can be decoded.

[SGaist]

@Kris-Revi said in QtWebSocket sending binary data with msgpack to ESP32 mcu:

if ( mIndata["selectedstrip"] )

You know that this if is going to fail if the the value associated with selectedstrip equals 0 ?

[Kris Revi]

@SGaist OH SHIT! i never thought of that xD