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Cannot get data from HTTP request

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  • T Offline
    T Offline
    t0msk
    wrote on last edited by t0msk
    #5

    I changed code like this:

        QSslConfiguration config = QSslConfiguration::defaultConfiguration();
        config.setProtocol(QSsl::TlsV1_2);
        QNetworkAccessManager *manager = new QNetworkAccessManager();
        QNetworkRequest request;
        QNetworkReply *reply = NULL;
    
        request.setHeader(QNetworkRequest::ServerHeader, "application/json");
        request.setSslConfiguration(config);
        request.setUrl(QUrl("https://www.archlinux.org/packages/search/json/?q=dolphin"));
    
        manager->get(request);
    
        connect(manager, SIGNAL(finished(QNetworkReply*)), this, SLOT(replyFinished(QNetworkReply*)));
    
        connect(manager, SIGNAL(error(QNetworkReply*)), this, SLOT(replyFinished(QNetworkReply*)));
    
        connect(manager, SIGNAL(sslErrors(QNetworkReply*)), this, SLOT(replyFinished(QNetworkReply*)));
    

    And still during debugging I dont stop in replyFinsihed function.

    Student who loves C/C++

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    0
    • SGaistS Offline
      SGaistS Offline
      SGaist
      Lifetime Qt Champion
      wrote on last edited by
      #6

      You should move the Qt 5 new syntax. It would have show you that error is not part of QNetworkAccessManager and that the signature of ssErrors is wrong.

      Interested in AI ? www.idiap.ch
      Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

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      1
      • T Offline
        T Offline
        t0msk
        wrote on last edited by
        #7

        @SGaist said in Cannot get data from HTTP request:

        You should move the Qt 5 new syntax. It would have show you that error is not part of QNetworkAccessManager and that the signature of ssErrors is wrong.

        Which syntax? I use Qt5.

        I tried even:

            QNetworkReply *reply = manager->get(request);
        
            connect(reply, SIGNAL(finished(reply)), this, SLOT(replyFinished(reply)));
        
            connect(reply, SIGNAL(error(reply)), this, SLOT(replyFinished(reply)));
        
            connect(reply, SIGNAL(sslErrors(reply)), this, SLOT(replyFinished(reply)));
        

        Student who loves C/C++

        mrjjM 1 Reply Last reply
        0
        • T t0msk

          @SGaist said in Cannot get data from HTTP request:

          You should move the Qt 5 new syntax. It would have show you that error is not part of QNetworkAccessManager and that the signature of ssErrors is wrong.

          Which syntax? I use Qt5.

          I tried even:

              QNetworkReply *reply = manager->get(request);
          
              connect(reply, SIGNAL(finished(reply)), this, SLOT(replyFinished(reply)));
          
              connect(reply, SIGNAL(error(reply)), this, SLOT(replyFinished(reply)));
          
              connect(reply, SIGNAL(sslErrors(reply)), this, SLOT(replyFinished(reply)));
          
          mrjjM Offline
          mrjjM Offline
          mrjj
          Lifetime Qt Champion
          wrote on last edited by mrjj
          #8

          @t0msk
          Hi
          The SIGNAL and SLOT macros is the "old way"
          its explained here
          https://wiki.qt.io/New_Signal_Slot_Syntax

          The main benefit is that it gives errors at compile time if its not correct.
          The SIGNAL and SLOT will eat most things and not complain but simply
          fail to work at runtime.

          1 Reply Last reply
          1
          • T Offline
            T Offline
            t0msk
            wrote on last edited by
            #9

            So I tried this:

            connect(
                    reply, &reply::finished,
                    this, &Manager::replyFinished
                );
            

            And I get:

            error: 'reply' is not a class, namespace, or enumeration
            

            I quite don't understand what to put into &reply yet :)

            Student who loves C/C++

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            0
            • SGaistS Offline
              SGaistS Offline
              SGaist
              Lifetime Qt Champion
              wrote on last edited by
              #10

              The name of the class containing the signal, same goes for the last parameter, it's the name of the class containing the slot.

              Interested in AI ? www.idiap.ch
              Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

              T 1 Reply Last reply
              1
              • SGaistS SGaist

                The name of the class containing the signal, same goes for the last parameter, it's the name of the class containing the slot.

                T Offline
                T Offline
                t0msk
                wrote on last edited by t0msk
                #11

                @SGaist

                Changed it to this:

                connect(
                        reply, &QNetworkReply::finished,
                        this, &Manager::replyFinished
                    );
                

                And I get:

                /usr/include/qt/QtCore/qobject.h:243: error: static assertion failed: The slot requires more arguments than the signal provides.
                  243 |         Q_STATIC_ASSERT_X(int(SignalType::ArgumentCount) >= int(SlotType::ArgumentCount),
                      |         ^~~~~~~~~~~~~~~~~
                

                Student who loves C/C++

                mrjjM 1 Reply Last reply
                0
                • T t0msk

                  @SGaist

                  Changed it to this:

                  connect(
                          reply, &QNetworkReply::finished,
                          this, &Manager::replyFinished
                      );
                  

                  And I get:

                  /usr/include/qt/QtCore/qobject.h:243: error: static assertion failed: The slot requires more arguments than the signal provides.
                    243 |         Q_STATIC_ASSERT_X(int(SignalType::ArgumentCount) >= int(SlotType::ArgumentCount),
                        |         ^~~~~~~~~~~~~~~~~
                  
                  mrjjM Offline
                  mrjjM Offline
                  mrjj
                  Lifetime Qt Champion
                  wrote on last edited by mrjj
                  #12

                  @t0msk said in Cannot get data from HTTP request:

                  QNetworkReply::finished,

                  Well you are mixing the classes/signals.
                  The reply's signals is
                  https://doc.qt.io/qt-5/qnetworkreply.html#finished
                  and have no QNetworkReply* parameter.

                  so i think you mean

                  connect(
                          Manager, &QNetworkAccessManager::finished,
                          this, &Manager::replyFinished
                      );
                  
                  T 1 Reply Last reply
                  1
                  • mrjjM mrjj

                    @t0msk said in Cannot get data from HTTP request:

                    QNetworkReply::finished,

                    Well you are mixing the classes/signals.
                    The reply's signals is
                    https://doc.qt.io/qt-5/qnetworkreply.html#finished
                    and have no QNetworkReply* parameter.

                    so i think you mean

                    connect(
                            Manager, &QNetworkAccessManager::finished,
                            this, &Manager::replyFinished
                        );
                    
                    T Offline
                    T Offline
                    t0msk
                    wrote on last edited by
                    #13

                    @mrjj said in Cannot get data from HTTP request:

                    @t0msk said in Cannot get data from HTTP request:

                    QNetworkReply::finished,

                    Well you are mixing the classes.
                    The reply signals is
                    https://doc.qt.io/qt-5/qnetworkreply.html#finished
                    and have no QNetworkReply* parameter.

                    so i think you mean

                    connect(
                            Manager, &QNetworkAccessManager::finished,
                            this, &Manager::replyFinished
                        );
                    

                    Thank you,
                    so now I have:

                        QSslConfiguration config = QSslConfiguration::defaultConfiguration();
                        config.setProtocol(QSsl::TlsV1_2);
                        QNetworkAccessManager *manager = new QNetworkAccessManager();
                        QNetworkRequest request;
                    
                    
                        request.setHeader(QNetworkRequest::ServerHeader, "application/json");
                        request.setSslConfiguration(config);
                        request.setUrl(QUrl("https://www.archlinux.org/packages/search/json/?q=dolphin"));
                    
                        QNetworkReply *reply = manager->get(request);
                    
                        connect(
                            manager, &QNetworkAccessManager::finished,
                            this, &Manager::replyFinished
                        );
                    
                        connect(
                            manager, &QNetworkAccessManager::sslErrors,
                            this, &Manager::replyFinished
                        );
                    
                    void Manager::replyFinished(QNetworkReply *reply)
                    {
                        qDebug() << reply->readAll();
                    
                        QString ha = reply->readAll();
                    
                        QString he;
                    }
                    

                    Still no output and no error :/

                    Student who loves C/C++

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                    0
                    • mrjjM Offline
                      mrjjM Offline
                      mrjj
                      Lifetime Qt Champion
                      wrote on last edited by
                      #14

                      Hi
                      Its a bit odd to connect all to the same slot but lets leave it for now.

                      now its time to
                      check your openSSL support !

                      what does
                      qDebug() << "i can use HTTPS:" << QSslSocket::supportsSsl();
                      qDebug() << "version" << QSslSocket::sslLibraryBuildVersionString();

                      say ?

                      T 1 Reply Last reply
                      1
                      • mrjjM mrjj

                        Hi
                        Its a bit odd to connect all to the same slot but lets leave it for now.

                        now its time to
                        check your openSSL support !

                        what does
                        qDebug() << "i can use HTTPS:" << QSslSocket::supportsSsl();
                        qDebug() << "version" << QSslSocket::sslLibraryBuildVersionString();

                        say ?

                        T Offline
                        T Offline
                        t0msk
                        wrote on last edited by
                        #15

                        @mrjj
                        It says:

                        i can use HTTPS: true
                        version "OpenSSL 1.1.1c  28 May 2019"
                        

                        Student who loves C/C++

                        1 Reply Last reply
                        1
                        • SGaistS Offline
                          SGaistS Offline
                          SGaist
                          Lifetime Qt Champion
                          wrote on last edited by
                          #16

                          What version of Qt are you using ?

                          One more thing: do these connections prior to calling get.

                          Interested in AI ? www.idiap.ch
                          Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                          T 1 Reply Last reply
                          0
                          • SGaistS SGaist

                            What version of Qt are you using ?

                            One more thing: do these connections prior to calling get.

                            T Offline
                            T Offline
                            t0msk
                            wrote on last edited by
                            #17

                            @SGaist Qt version is 5.13.1

                            Student who loves C/C++

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                            • T Offline
                              T Offline
                              t0msk
                              wrote on last edited by
                              #18

                              So where can be problem? :/

                              Student who loves C/C++

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                              0
                              • SGaistS Offline
                                SGaistS Offline
                                SGaist
                                Lifetime Qt Champion
                                wrote on last edited by SGaist
                                #19

                                Did you move the connection statements as I suggested ?

                                Interested in AI ? www.idiap.ch
                                Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

                                T 1 Reply Last reply
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                                • SGaistS SGaist

                                  Did you move the connection statements as I suggested ?

                                  T Offline
                                  T Offline
                                  t0msk
                                  wrote on last edited by
                                  #20

                                  @SGaist I dont know what do you mean

                                  Student who loves C/C++

                                  JonBJ 1 Reply Last reply
                                  0
                                  • T t0msk

                                    @SGaist I dont know what do you mean

                                    JonBJ Online
                                    JonBJ Online
                                    JonB
                                    wrote on last edited by JonB
                                    #21

                                    @t0msk

                                    @SGaist wrote

                                    Did you move the connection statements as I suggested ?

                                    In your code you show:

                                        QNetworkReply *reply = manager->get(request);
                                    
                                        connect(
                                            manager, &QNetworkAccessManager::finished,
                                            this, &Manager::replyFinished
                                        );
                                    
                                        connect(
                                            manager, &QNetworkAccessManager::sslErrors,
                                            this, &Manager::replyFinished
                                        );
                                    

                                    You are calling the manager->get(request) before you have connected the signals/slots on manager, which may/will be too late. He is asking you to change over anything like that to

                                        connect(
                                            manager, &QNetworkAccessManager::finished,
                                            this, &Manager::replyFinished
                                        );
                                    
                                        connect(
                                            manager, &QNetworkAccessManager::sslErrors,
                                            this, &Manager::replyFinished
                                        );
                                    
                                        QNetworkReply *reply = manager->get(request);
                                    

                                    so you move the connection statements to before the get(request). So we get to see finished or quite possibly errors from the request. In general, you need to set up signals/slots as soon as you create an object (manager here), before you call anything which could raise a signal.

                                    1 Reply Last reply
                                    4
                                    • T Offline
                                      T Offline
                                      t0msk
                                      wrote on last edited by
                                      #22

                                      Changed it like:

                                          connect(
                                              manager, &QNetworkAccessManager::finished,
                                              this, &Manager::replyFinished
                                          );
                                      
                                          connect(
                                              manager, &QNetworkAccessManager::sslErrors,
                                              this, &Manager::replyFinished
                                          );
                                      
                                          QNetworkReply *reply = manager->get(request);
                                      

                                      and still doesn't work, no error, no reply.

                                      Student who loves C/C++

                                      1 Reply Last reply
                                      0

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