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How to Test Ftp server availability

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  • siropS Offline
    siropS Offline
    sirop
    wrote on last edited by
    #6

    The above example does everything you want, as you get
    QNetworkReply reply .

    In the next step you can do:

    @reply.error()@

    which yields http://qt-project.org/doc/qt-5/qnetworkreply.html#NetworkError-enum .

    To be, or not to be: that is the question:
    Whether ’tis nobler in the mind to suffer
    The slings and arrows of outrageous fortune,
    Or to take arms against a sea of troubles,
    And by opposing end them?

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    • p3c0P Offline
      p3c0P Offline
      p3c0
      Moderators
      wrote on last edited by
      #7

      Hi,

      Did you check "authenticationRequired":http://qt-project.org/doc/qt-5/qnetworkaccessmanager.html#authenticationRequired ?
      Until valid credentials are given the signal is emitted again and again. If I understood you correctly this can be used in your case.

      157

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      • B Offline
        B Offline
        beemaneni
        wrote on last edited by
        #8

        Hi sirop,
        The above examples does everything ..i get error from QNetworkReply as "NO ERROR". But i do not want to send that text file and verify the accessibility..
        Here we use
        @ reply = manager.put(QNetworkRequest(url), data);@
        i want to send only the ftp address as
        reply = manager.put or get (QNetworkRequest(url));

        I am not sure what function to use whether it is get or put or something else..?
        Let me give an example like i.e..the way we ping and find the accessibility of a network just with address

        Thanks
        Bala Beemaneni

        Bala B
        Infinite Computer systems
        Chennai

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        • siropS Offline
          siropS Offline
          sirop
          wrote on last edited by
          #9

          I would then use:
          @QNetworkReply * QNetworkAccessManager::get(const QNetworkRequest & request)@

          To be, or not to be: that is the question:
          Whether ’tis nobler in the mind to suffer
          The slings and arrows of outrageous fortune,
          Or to take arms against a sea of troubles,
          And by opposing end them?

          1 Reply Last reply
          0
          • B Offline
            B Offline
            beemaneni
            wrote on last edited by
            #10

            Hi p3c0
            That signal emits only if authentication either username or password set mismatches.What i need is i want is on button click need to just login in to ftp server and on another button click logout from ftp server.

            Bala B
            Infinite Computer systems
            Chennai

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            • B Offline
              B Offline
              beemaneni
              wrote on last edited by
              #11

              hi sirop,
              hi i did test that but of no use.Here is my code...
              @ QUrl testFtp("ftp://"+server);
              testFtp.setUserName(userId);
              testFtp.setPassword(password);
              testFtp.setPort(21);
              request.setUrl(testFtp);

              // reply = manager.put(request,testData);
              reply = manager.get(request);
              connect(reply,SIGNAL(readyRead()),this,SLOT(readData()));
              connect(reply,SIGNAL(uploadProgress(qint64,qint64)),this,SLOT(fileTransferProgress(qint64,qint64)));
              connect(reply, SIGNAL(error(QNetworkReply::NetworkError)),this, SLOT(slotError(QNetworkReply::NetworkError)));
              connect(reply, SIGNAL(sslErrors(QList<QSslError>)),this, SLOT(slotSslErrors(QList<QSslError>)));@

              i get the error in Network Error says "202".
              i.e: QNetworkReply::ContentOperationNotPermittedError

              Bala B
              Infinite Computer systems
              Chennai

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              • p3c0P Offline
                p3c0P Offline
                p3c0
                Moderators
                wrote on last edited by
                #12

                Well then another way would be to try to download file from ftp server. If it exists then on finished signal you should get NoError
                Eg:
                @
                manager->get(QNetworkRequest(QUrl("ftp://ftp.ed.ac.uk/pub/Unix/NT4_PlainPassword.reg")));
                ...

                void MainWindow::replyFinished(QNetworkReply *reply)
                {
                qDebug() << "Reply: " << reply->error(); //will show 0
                }
                @

                157

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                • B Offline
                  B Offline
                  beemaneni
                  wrote on last edited by
                  #13

                  hi dude...
                  thats not the way i guess.We just have an ip address,user,password.Just we need to ensure whether we are reachable to the server or not..We do not know what are the contents in ftp.So we cant download a file.
                  So cant we just login or connect to ftp server using QNAM?
                  What about the QNetworkSession? I could not understand this..can u suggest something else

                  Thanks for ur interest p3c0

                  Bala B
                  Infinite Computer systems
                  Chennai

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                  • p3c0P Offline
                    p3c0P Offline
                    p3c0
                    Moderators
                    wrote on last edited by
                    #14

                    Deleted

                    157

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                    • p3c0P Offline
                      p3c0P Offline
                      p3c0
                      Moderators
                      wrote on last edited by
                      #15

                      Another way would be to try to connect the server using QTcpSocket as
                      @
                      QTcpSocket *socket = new QTcpSocket;
                      connect(socket,SIGNAL(connected()),this,SLOT(onConnected()));
                      socket->connectToHost("192.168.1.145",21);
                      if(!socket->waitForConnected(2000)) {
                      qDebug() << "Not connected";
                      socket->abort();
                      }
                      @

                      If it succeeds then onConnected will be called immediately. But not sure if this is the recommended way.

                      157

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                      • B Offline
                        B Offline
                        beemaneni
                        wrote on last edited by
                        #16

                        hi ,
                        we may not have hostnames for all the ftp servers.So may not help much.
                        yeah using TCP will work.Bt right now i am googling for the QNAM API's which can do that.

                        Let me know if u get any from QNAM or supporting ones

                        Bala B
                        Infinite Computer systems
                        Chennai

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                        • B Offline
                          B Offline
                          beemaneni
                          wrote on last edited by
                          #17

                          Hii guys

                          Any updates on the previous ???
                          And i would like to add one more to this as..

                          1. When the network we try to connect is not in reach it does not give error on time..It takes a lot of time and some times it never returns any error..How do i handle this?

                             @    connect(reply, SIGNAL(error(QNetworkReply::NetworkError)),this, SLOT(slotError(QNetworkReply::NetworkError)));@
                            

                          i am catching above signal which takes a lot of time...
                          Are there any best methods?

                          Thanks

                          Bala B
                          Infinite Computer systems
                          Chennai

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                          • siropS Offline
                            siropS Offline
                            sirop
                            wrote on last edited by
                            #18

                            Try to use QTimer ?

                            To be, or not to be: that is the question:
                            Whether ’tis nobler in the mind to suffer
                            The slings and arrows of outrageous fortune,
                            Or to take arms against a sea of troubles,
                            And by opposing end them?

                            1 Reply Last reply
                            0
                            • B Offline
                              B Offline
                              beemaneni
                              wrote on last edited by
                              #19

                              Hi,
                              i feel there will be a straight way to do it with QNetworkAccessManager or with QNetworkReply.Probably we are missing that..

                              Thanks

                              Bala B
                              Infinite Computer systems
                              Chennai

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