Sending QJsonArray over socket

Kris Revi

Code Qt Side

void MainWindow::selectedImageDisplay(QString img)
{
    QImage imageObject;    // Make a new imageObject
    imageObject.load(img); // Load the image from path

    imageObject = imageObject.convertToFormat(QImage::Format_RGB16);

    QJsonArray RGB565;
    for(int y = 0; y < imageObject.height(); y++)
    {
        const quint16 *line = reinterpret_cast<const quint16*>(imageObject.constScanLine(y));
        for(int x = 0; x < imageObject.width(); x++)
        {
            RGB565 << *(line++);
        }
    }

    qDebug() << RGB565;
    socket.sendCommandStrip(QString("pixArt"), RGB565);
}

Code ESP32 Side

class MatrixSocket
{ 
    public:
        static void webSocketEvent(uint8_t num, WStype_t type, uint8_t *payload, size_t length)
        {
            Serial.println("Incoming data from socket!");

            IPAddress ip = webSocket.remoteIP(num);

            const size_t CAPACITY = JSON_ARRAY_SIZE(128); // Json Array Size (128x128 image size)

            DynamicJsonDocument inData(CAPACITY);
            StaticJsonDocument<512> outData;

            DeserializationError err = deserializeJson(inData, payload);

            switch (err.code())
            {
                case DeserializationError::Ok:
                    Serial.println("Deserialization succeeded");
                    break;
                case DeserializationError::EmptyInput:
                    Serial.println("Empty input!");
                    break;
                case DeserializationError::IncompleteInput:
                    Serial.println("Incomplete input!");
                    break;
                case DeserializationError::InvalidInput:
                    Serial.println("Invalid input!");
                    break;
                case DeserializationError::NoMemory:
                    Serial.println("Not enough memory");
                    break;
                case DeserializationError::NotSupported:
                    Serial.println("Not Supported");
                    break;
                case DeserializationError::TooDeep:
                    Serial.println("Too Deep");
                    break;
                default:
                    Serial.println("Deserialization failed");
                    break;
            }

            String outJsonData;

            if (inData["reqDeviceInfo"] && inData["reqDeviceInfo"] == "yes")
            {
                outData["ledtype"]              = "MATRIX";
                
                serializeJson(outData, outJsonData);
                webSocket.sendTXT(num, outJsonData);

                Serial.println("Sending out data!");
            }

            if (inData["pixArt"])
            { 
                Serial.println("Pixel Data Incoming!");
                JsonArray src = inData["pixArt"].as<JsonArray>();
                int i = 0;
                for (JsonVariant p : src)
                {
                    if (i >= 256) break; // just to be safe!
                    pixelArt[i++] = p.as<uint16_t>();
                }
            }

            switch (type)
            {
                case WStype_CONNECTED:
                    Serial.printf("[SOCKET][STATUS][%u] Connected from %d.%d.%d.%d url: %s \n", num, ip[0], ip[1], ip[2], ip[3], payload);
                break;

                case WStype_DISCONNECTED: 
                    Serial.printf("[SOCKET][STATUS] [%u] Disconnected! \n", num);
                break;

                case WStype_ERROR:
                    Serial.println("[SOCKET][ERROR] Oh Shit! \n");
                break;

                /*case WStype_TEXT:
                case WStype_BIN:
                case WStype_FRAGMENT_TEXT_START:
                case WStype_FRAGMENT_BIN_START:
                case WStype_FRAGMENT:
                case WStype_FRAGMENT_FIN:*/

                default:
                break;
                
            }
        }

Problem
When printing out the QJsonArray RGB565 after it's done i get this https://pastebin.com/3zgVpfkG big ass array (and that is fine)
but when it sends it over to my ESP32 all i get is

Incoming data from socket!
Empty input!
[SOCKET][STATUS] [0] Disconnected!

then i get disconnected :S why? what am i doing wrong?

Christian Ehrlicher

Then print out what you really receive to see if it's what you're sending. Also print out what you really send on the sender side.

Kris Revi

So i did this

void Socket::sendCommandStrip(const QString &bName, const QJsonValue bValue)
{
    m_webSocket.sendTextMessage(QJsonDocument(QJsonObject{{bName, bValue}}).toJson(QJsonDocument::Compact));
    qDebug() << QJsonDocument(QJsonObject{{bName, bValue}}).toJson(QJsonDocument::Compact);
}

and got

"{\"pixArt\":[]}"

now my question is, why? :S

@Christian-Ehrlicher

if i do this

socket.sendCommandStrip(QString("pixArt"), QJsonValue(RGB565).toArray());

i get the correct output (im not copying all 16k + here)

"{\"pixArt\":[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,30912,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,30912,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,30912,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,30912,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,30912,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,30912,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,30912,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,30912,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,30912,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,30912,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,30912,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,30912,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,30912,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,61888,

it ends with this

0,0,0,0,0,0,0,0,0]}"
[SOCKET][INFO] We are closing the connection

again it disconnects me after :S

on the ESP32 side i get this

Incoming data from socket!
Empty input!
[SOCKET][STATUS] [0] Disconnected!

Christian Ehrlicher

I said you should output what you really send, not what you pass to a function you wrote.

Kris Revi

@Christian-Ehrlicher that is what i send....

qDebug() << QJsonDocument(QJsonObject{{bName, bValue}}).toJson(QJsonDocument::Compact);

Christian Ehrlicher

So what do you get on the esp side?

Kris Revi

@Christian-Ehrlicher the same as stated above

Incoming data from socket!
Empty input!
[SOCKET][STATUS] [0] Disconnected!

it claims inData['pixArt'] is empty and the disconnects me :S

Christian Ehrlicher

@Kris-Revi said in Sending QJsonArray over socket:

the same as stated above

I don't want processed output but the raw data (for the third time...)

Kris Revi

@Christian-Ehrlicher
like this?

            JsonArray test = inData["pixArt"];

            Serial.println(test);
            Serial.println(inData["pixArt"].as<JsonArray>());

this just gives me

Incoming data from socket!
0
0
Empty input!
[SOCKET][STATUS] [0] Disconnected!

Christian Ehrlicher

I'm giving up... don't know what's so hard to print out the raw incoming data. Good luck.

JKSH

@Kris-Revi said in Sending QJsonArray over socket:

like this?

No. Please show us your payload. What does it look like before you passed it into deserializeJson()? (This is what @Christian-Ehrlicher meant by "raw data")

Also:

What is the value of length in webSocketEvent()?
Converting an image into a QJsonArray is very expensive and inefficient. What is the purpose using QJsonArray here?