Trouble connecting to aws iot using QMqtt and QSsl stack.

[eluppai]

Brief Description: I am using QMqtt and QSsl stack to connect to perform a secure Mqtt connection and then publish some data on the aws server. But the Client state always stays on connecting never changes to connected

Expected behavior: First I tried connecting to test.mosquitto.org, I was able to connect and publish the data. So the expected behavior was to see some similar results.

Send_MqTT::Send_MqTT(QObject *parent) : QObject(parent)
{
    m_socket=new QSslSocket();
    m_client=new QMqttClient();
    m_topicname = new QMqttTopicName();
    m_topicname->setName("Pubtopic/test");

    connect(m_client,&QMqttClient::stateChanged,[](QMqttClient::ClientState state){
        if(state == QMqttClient::Disconnected)
        {
            qDebug()<<"State is Disconnected: "<<state;
        }
        else if(state == QMqttClient::Connecting)
        {
            qDebug()<<"State is Connecting: "<<state;
        }
        else if(state == QMqttClient::Connected)
        {
            qDebug()<<"State is Connected: "<<state;
        }

    });
    connect(m_client,&QMqttClient::errorChanged,[](QMqttClient::ClientError error_state){
        qDebug()<<"Error State is: "<<error_state;
    });
}
void Send_MqTT::connect_toserver()
{
    if(QSslSocket::supportsSsl())
      {
        qDebug()<<"SSL SUPORTED";
        m_socket->setLocalCertificate("<certificatelocation>",QSsl::Pem);
        m_socket->setPrivateKey("<private Key Location>",QSsl::Rsa,QSsl::Pem);
        m_client->setHostname("host-name");
        m_client->setPort(8883);
        m_client->setTransport(m_socket,QMqttClient::SecureSocket);
        m_client->connectToHostEncrypted();
    }
}

Am I missing something. Do I have to set Mqtt connection properties before I begin the connection?

[SGaist]

Hi,

Can you explain what result you are getting ?
What errors are you getting ?
What version of Qt are you using ?

[eluppai]

@sgaist The clientState stays on connecting and never goes to connected. Because of which I am unable to publish any data. The ClientState has to transition to connected for me to publish or subscribe

enum QMqttClient::ClientState
Constant	                             Value	
QMqttClient::Disconnected	              0	
QMqttClient::Connecting	                      1	      
QMqttClient::Connected	                      2

So the state always stays on connecting. I do not get any errors.
Qt version is 5.12.3
and system is an Ubuntu 18.04

[SGaist]

From the looks of it, you didn't connect any of the QOpenSSLSocket error signals. You should add them.

[eluppai]

@SGaist okay I will add that. But Don't you think if there was any error. Mqtt should also throw an error. Because if I remove a certificate or a private key from the file or add any wrong information, I do get an error stating that the transport properties are not set properly and the ClientState goes to disconnected it does not stays on connecting for a long period of time.