Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
  • Search
  • Get Qt Extensions
  • Unsolved
Collapse
Brand Logo
  1. Home
  2. Qt Development
  3. General and Desktop
  4. Cannot get data from HTTP request
Forum Updated to NodeBB v4.3 + New Features

Cannot get data from HTTP request

Scheduled Pinned Locked Moved Unsolved General and Desktop
22 Posts 5 Posters 2.3k Views 3 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • mrjjM Offline
    mrjjM Offline
    mrjj
    Lifetime Qt Champion
    wrote on last edited by mrjj
    #4

    Hi
    I dont see any
    manager->get(request);
    or similar to actually run the Request.

    Also, you are using HTTPS so did you install the
    OpenSSL 1.0.2 and put it in a PATH that your app can find?
    (or next to the app in the build folder)

    Note:
    5.12.4 Released with support for OpenSSL 1.1.1
    https://www.qt.io/blog/2019/06/17/qt-5-12-4-released-support-openssl-1-1-1

    Try to add
    qDebug() << QSslSocket::supportsSsl();
    qDebug() << QSslSocket::sslLibraryBuildVersionString();

    and see if it say TRUE or FALSE
    and it will also list the openSSL Lib it supports.
    like
    "OpenSSL 1.1.1b 26 Feb 2019"

    1 Reply Last reply
    1
    • 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++

      1 Reply Last reply
      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

        1 Reply Last reply
        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++

              1 Reply Last reply
              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++

                      1 Reply Last reply
                      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++

                              1 Reply Last reply
                              0
                              • T Offline
                                T Offline
                                t0msk
                                wrote on last edited by
                                #18

                                So where can be problem? :/

                                Student who loves C/C++

                                1 Reply Last reply
                                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
                                  0
                                  • 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 Offline
                                      JonBJ Offline
                                      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

                                        • Login

                                        • Login or register to search.
                                        • First post
                                          Last post
                                        0
                                        • Categories
                                        • Recent
                                        • Tags
                                        • Popular
                                        • Users
                                        • Groups
                                        • Search
                                        • Get Qt Extensions
                                        • Unsolved