Simple Publish (No consume)

[bprinsloo]

I have been messing around for hours now. All I want is a simple send of a message (An XML) to rabbitmq. I have the receiver code written in Java, so that is irrelevant. I just want a simple send method.

This sample uses the timer with SLOTS. I modified it to only execute once for the send, but it seems the thread never closes since the app doesn't exit. If I add an event with my own signal to exit after the "publish", the message doesn't seem to be posted.

My Run has been changed as follow :
void run() { //Sends a single message m_myLongTimer = new QTimer(this); m_myLongTimer->setInterval(3000); m_myLongTimer->setSingleShot(true); connect(m_myLongTimer, SIGNAL(timeout()), SLOT(sendMessage())); m_myLongTimer->start(); }

and I added a slot on the constructor as follow : connect(this, SIGNAL(AppIsDone()),SLOT(QuitApp()));

And the code of QuitApp() is : void QuitApp() { qDebug() << "Still here!!!!!!!!!"; exit(-1); }

At the end of sendMessage I added : emit AppIsDone();

It work as expected, fire after the supposed publish, but unless the thread is left as is it just doesn't post. If I remove the exit(-1), it doesn't exit and the message is posted. If I put it back, it say it's done, but nothing is published.

Is there any signal I am missing out on here? Is there a reason why the thread need to stay active for the post to proceed?

[fuCtor]

Show full example. In this part I can't understand in which thread you try send message and don't see how you are working with this thread.

[bprinsloo]

Thank you for the extremely quick response! Really appreciate it :+1:

I basically used your Send.h as a template, and created "MySend.h" as below as a test. The part changed is under "Run". Basically this used to be a timer defined as :

    void run()
    {
        QTimer* timer = new QTimer(this);
        timer->setInterval(2468);
        connect(timer, SIGNAL(timeout()), SLOT(sendMessage()));
        timer->start();
    }

I changed to be a singleshot only, and added a method to exit.

#ifndef MYSEND_H
#define MYSEND_H

#include <QObject>
#include <QRunnable>
#include <QDebug>
#include <QList>
#include <QByteArray>
#include <QDateTime>
#include <QTimer>

#include "qamqp/amqp.h"
#include "qamqp/amqp_exchange.h"
#include "qamqp/amqp_queue.h"

namespace QAMQP
{

namespace dsmApps
{

class MySend : public QObject, public QRunnable
{
    Q_OBJECT

    typedef QObject super;

signals:
    void AppIsDone();
    void timeout();

public:
    explicit MySend(const QString& address, const QString& sendMsg, QObject *parent)
        : super(parent), sendMsg_(sendMsg)
    {
        connect(this, SIGNAL(AppIsDone()),SLOT(QuitApp()));  //<----------------------------------------------ADDED BY ME
        // Create AMQP client
        client = new QAMQP::Client(this);
        client->open(QUrl(address));

        // Retrieve the "Default" exchange
        // No need to declare (i.e. to create), nor to bind to a queue
        exchange_ =  client->createExchange();

        // Create the "ETEST" queue
        // This isn't mandatory but if it doesn't exist, the messages are lost
        client
            ->createQueue("ETEST", exchange_->channelNumber())
                ->declare();

       // client->close();
        client->disconnect();
    }

    void run()
    {
        //Sends a single message
        m_myLongTimer = new QTimer(this);
        m_myLongTimer->setInterval(3000);
        m_myLongTimer->setSingleShot(true); //<-------------------------------------------ADDED BY ME
        connect(m_myLongTimer, SIGNAL(timeout()), SLOT(sendMessage()));
        m_myLongTimer->start();
    }

protected slots:
    void QuitApp() {  //<----------------------------------------------ADDED BY ME
        qDebug() << "Still here!!!!!!!!!";
       exit(-1);
    }

    void sendMessage()
    {
        static quint64 counter = 0;
      /*  QAMQP::Exchange::MessageProperties properties;
        properties[QAMQP::Frame::Content::cpDeliveryMode] = 2; // Make message persistent
*/
        QString message(QString("[%1: %2] %3")
          .arg(++counter)
          .arg(QDateTime::currentDateTime().toString(Qt::ISODate))
          .arg(sendMsg_));
        qDebug() << "Send::sendMessage NOW " << message;

        exchange_->publish(message, "ETEST");
        emit AppIsDone();    //<----------------------------------------------ADDED BY ME
    }

private:
    QString sendMsg_;
    QTimer*   m_myLongTimer;

    QAMQP::Exchange* exchange_;
    QAMQP::Client* client;
};

}

}

#endif // MYSEND_H

[fuCtor]

exchange_->publish(message, "ETEST"); emit AppIsDone(); //<----------------------------------------------ADDED MY ME

Network methods is async, but SIGNAL\SLOT in one thream is sync. When your emit signal, app don't have time for message sending.

[bprinsloo]

Is there a way around this? Thread sleeps will obviously not work in this case.

[fuCtor]

Connect SIGNAL AppIsDone with Timer SIGNAL timeout and make singleshot timer.

[bprinsloo]

Thank you very much!! This work like a charm. This i added at the end after doing the publish :+1:

exchange_->publish(message, "ETEST");
        m_myEndTimer = new QTimer(this);
        m_myEndTimer->setInterval(3000);
        m_myEndTimer->setSingleShot(true);
        connect(m_myEndTimer, SIGNAL(timeout()), SLOT(QuitApp()));
        m_myEndTimer->start();

This might help someone else. The 3s should of course be adjusted just in case for latency etc, so a ping and a simple calc must still be performed rather than hardcode it, but overall it works. I consider this closed, thank you for help.