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embed a python function into my Qt App.

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  • V vinaygopal

    @jsulm

    QT       += core gui networkauth
    
    greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
    
    TARGET = example_project
    TEMPLATE = app
    
    
    # The following define makes your compiler emit warnings if you use
    # any feature of Qt which has been marked as deprecated (the exact warnings
    # depend on your compiler). Please consult the documentation of the
    # deprecated API in order to know how to port your code away from it.
    DEFINES += QT_DEPRECATED_WARNINGS
    
    # You can also make your code fail to compile if you use deprecated APIs.
    # In order to do so, uncomment the following line.
    # You can also select to disable deprecated APIs only up to a certain version of Qt.
    #DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0
    
    CONFIG += c++11
    
    SOURCES += \
            main.cpp \
            google_widget.cpp
    
    HEADERS += \
            google_widget.h
    
    FORMS += \
            google_widget.ui
    
    # Default rules for deployment.
    qnx: target.path = /tmp/$${TARGET}/bin
    else: unix:!android: target.path = /opt/$${TARGET}/bin
    !isEmpty(target.path): INSTALLS += target
    
    DISTFILES += \
        upload_to_cloud.py
    
    
    #CONFIG += no_lflags_merge
    
    INCLUDEPATH +="C:\Users\vinay\AppData\Local\Programs\Python\Python37-32\include"
    
    
    
    win32:CONFIG(release, debug|release): LIBS += -L$$PWD/../../../AppData/Local/Programs/Python/Python37-32/libs/ -lpython37
    else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/../../../AppData/Local/Programs/Python/Python37-32/libs/ -lpython37d
    else:unix: LIBS += -L$$PWD/../../../AppData/Local/Programs/Python/Python37-32/libs/ -lpython37
    
    
    win32-g++:CONFIG(release, debug|release): PRE_TARGETDEPS += $$PWD/../../../AppData/Local/Programs/Python/Python37-32/libs/libpython37.a
    else:win32-g++:CONFIG(debug, debug|release): PRE_TARGETDEPS += $$PWD/../../../AppData/Local/Programs/Python/Python37-32/libs/libpython37d.a
    else:win32:!win32-g++:CONFIG(release, debug|release): PRE_TARGETDEPS += $$PWD/../../../AppData/Local/Programs/Python/Python37-32/libs/python37.lib
    else:win32:!win32-g++:CONFIG(debug, debug|release): PRE_TARGETDEPS += $$PWD/../../../AppData/Local/Programs/Python/Python37-32/libs/python37d.lib
    else:unix: PRE_TARGETDEPS += $$PWD/../../../AppData/Local/Programs/Python/Python37-32/libs/libpython37.a
    
    
    jsulmJ Offline
    jsulmJ Offline
    jsulm
    Lifetime Qt Champion
    wrote on last edited by
    #14

    @vinaygopal On Windows it should be:

    LIBS += $$PWD/../../../AppData/Local/Programs/Python/Python37-32/libs/python37.lib
    

    See https://doc.qt.io/qt-5/qmake-variable-reference.html#libs

    https://forum.qt.io/topic/113070/qt-code-of-conduct

    V 1 Reply Last reply
    2
    • jsulmJ jsulm

      @vinaygopal On Windows it should be:

      LIBS += $$PWD/../../../AppData/Local/Programs/Python/Python37-32/libs/python37.lib
      

      See https://doc.qt.io/qt-5/qmake-variable-reference.html#libs

      V Offline
      V Offline
      vinaygopal
      wrote on last edited by
      #15

      @jsulm i did add the library as you had recomended it still did'nt work and more importantly i figured the module python.h and its equivalent library is not compatible with mingw gcc compiler it is only compatible with microsoft specific compilers as suggested by this question (https://stackoverflow.com/questions/6731100/link-to-python-with-mingw) they have provided an answer but is there a simpler way to get this done?

      jsulmJ 1 Reply Last reply
      0
      • V vinaygopal

        @jsulm i did add the library as you had recomended it still did'nt work and more importantly i figured the module python.h and its equivalent library is not compatible with mingw gcc compiler it is only compatible with microsoft specific compilers as suggested by this question (https://stackoverflow.com/questions/6731100/link-to-python-with-mingw) they have provided an answer but is there a simpler way to get this done?

        jsulmJ Offline
        jsulmJ Offline
        jsulm
        Lifetime Qt Champion
        wrote on last edited by
        #16

        @vinaygopal One question: do you build your app as 64bit? Your Python seems to be 32bit.

        https://forum.qt.io/topic/113070/qt-code-of-conduct

        V 1 Reply Last reply
        0
        • jsulmJ jsulm

          @vinaygopal One question: do you build your app as 64bit? Your Python seems to be 32bit.

          V Offline
          V Offline
          vinaygopal
          wrote on last edited by
          #17

          @jsulm i am building my apps in the 64 bit configuration. shoudl i change it to 32 bit and try building the program again?

          jsulmJ 1 Reply Last reply
          0
          • V vinaygopal

            @jsulm i am building my apps in the 64 bit configuration. shoudl i change it to 32 bit and try building the program again?

            jsulmJ Offline
            jsulmJ Offline
            jsulm
            Lifetime Qt Champion
            wrote on last edited by
            #18

            @vinaygopal said in embed a python function into my Qt App.:

            shoudl i change it to 32 bit

            Yes, you can't mix 32bit and 64bit

            https://forum.qt.io/topic/113070/qt-code-of-conduct

            V 1 Reply Last reply
            0
            • jsulmJ jsulm

              @vinaygopal said in embed a python function into my Qt App.:

              shoudl i change it to 32 bit

              Yes, you can't mix 32bit and 64bit

              V Offline
              V Offline
              vinaygopal
              wrote on last edited by
              #19

              @jsulm uninstalled python 32 bit and reinstalled 64bit version of python and included the libraries still the same error

              :-1: error: No rule to make target 'C:/Users/vinay/Documents/first_qml_training/example_project/../../../AppData/Local/Programs/Python/Python38/libs/libpython38d.a', needed by 'debug/example_project.exe'. Stop.

              jsulmJ 1 Reply Last reply
              0
              • V vinaygopal

                @jsulm uninstalled python 32 bit and reinstalled 64bit version of python and included the libraries still the same error

                :-1: error: No rule to make target 'C:/Users/vinay/Documents/first_qml_training/example_project/../../../AppData/Local/Programs/Python/Python38/libs/libpython38d.a', needed by 'debug/example_project.exe'. Stop.

                jsulmJ Offline
                jsulmJ Offline
                jsulm
                Lifetime Qt Champion
                wrote on last edited by
                #20

                @vinaygopal Can you show your current pro file?
                Also did you a clean rebuild?

                https://forum.qt.io/topic/113070/qt-code-of-conduct

                V 1 Reply Last reply
                0
                • jsulmJ jsulm

                  @vinaygopal Can you show your current pro file?
                  Also did you a clean rebuild?

                  V Offline
                  V Offline
                  vinaygopal
                  wrote on last edited by
                  #21

                  @jsulm yes i clean the build run qmake and then build the file everytime i change the pro file

                  #-------------------------------------------------
                  #
                  # Project created by QtCreator 2019-11-21T10:31:03
                  #
                  #-------------------------------------------------
                  
                  QT       += core gui networkauth
                  
                  greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
                  
                  TARGET = example_project
                  TEMPLATE = app
                  
                  
                  # The following define makes your compiler emit warnings if you use
                  # any feature of Qt which has been marked as deprecated (the exact warnings
                  # depend on your compiler). Please consult the documentation of the
                  # deprecated API in order to know how to port your code away from it.
                  DEFINES += QT_DEPRECATED_WARNINGS
                  
                  # You can also make your code fail to compile if you use deprecated APIs.
                  # In order to do so, uncomment the following line.
                  # You can also select to disable deprecated APIs only up to a certain version of Qt.
                  #DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0
                  
                  CONFIG += c++11
                  
                  SOURCES += \
                          main.cpp \
                          google_widget.cpp
                  
                  HEADERS += \
                          google_widget.h
                  
                  FORMS += \
                          google_widget.ui
                  
                  # Default rules for deployment.
                  qnx: target.path = /tmp/$${TARGET}/bin
                  else: unix:!android: target.path = /opt/$${TARGET}/bin
                  !isEmpty(target.path): INSTALLS += target
                  
                  DISTFILES += \
                      upload_to_cloud.py
                  
                  
                  #CONFIG += no_lflags_merge
                  
                  INCLUDEPATH="C:/Users/vinay/AppData/Local/Programs/Python/Python38/include"
                  LIBS += $$PWD/../../../AppData/Local/Programs/Python/Python38/libs/python38.lib
                  
                  jsulmJ 1 Reply Last reply
                  0
                  • JonBJ Offline
                    JonBJ Offline
                    JonB
                    wrote on last edited by JonB
                    #22

                    I'm keeping an eye on this thread. As I said right at the start

                    You can indeed go down @jsulm's path, but embedding is a lot more involved than just running a subprocess.
                    But as phrased if all you want to do is run an external script with some command-line arguments [...], it really is simple to do with QProcess, should take one minute to write.

                    I do hope/presume that (for both your sakes) for use case here all this embedding is indeed required and worth the effort! :)

                    V 1 Reply Last reply
                    1
                    • V vinaygopal

                      @jsulm yes i clean the build run qmake and then build the file everytime i change the pro file

                      #-------------------------------------------------
                      #
                      # Project created by QtCreator 2019-11-21T10:31:03
                      #
                      #-------------------------------------------------
                      
                      QT       += core gui networkauth
                      
                      greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
                      
                      TARGET = example_project
                      TEMPLATE = app
                      
                      
                      # The following define makes your compiler emit warnings if you use
                      # any feature of Qt which has been marked as deprecated (the exact warnings
                      # depend on your compiler). Please consult the documentation of the
                      # deprecated API in order to know how to port your code away from it.
                      DEFINES += QT_DEPRECATED_WARNINGS
                      
                      # You can also make your code fail to compile if you use deprecated APIs.
                      # In order to do so, uncomment the following line.
                      # You can also select to disable deprecated APIs only up to a certain version of Qt.
                      #DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0
                      
                      CONFIG += c++11
                      
                      SOURCES += \
                              main.cpp \
                              google_widget.cpp
                      
                      HEADERS += \
                              google_widget.h
                      
                      FORMS += \
                              google_widget.ui
                      
                      # Default rules for deployment.
                      qnx: target.path = /tmp/$${TARGET}/bin
                      else: unix:!android: target.path = /opt/$${TARGET}/bin
                      !isEmpty(target.path): INSTALLS += target
                      
                      DISTFILES += \
                          upload_to_cloud.py
                      
                      
                      #CONFIG += no_lflags_merge
                      
                      INCLUDEPATH="C:/Users/vinay/AppData/Local/Programs/Python/Python38/include"
                      LIBS += $$PWD/../../../AppData/Local/Programs/Python/Python38/libs/python38.lib
                      
                      jsulmJ Offline
                      jsulmJ Offline
                      jsulm
                      Lifetime Qt Champion
                      wrote on last edited by
                      #23

                      @vinaygopal Looks correct to me. I would try this:

                      • Delete build directory
                      • Run qmake
                      • build

                      https://forum.qt.io/topic/113070/qt-code-of-conduct

                      1 Reply Last reply
                      0
                      • V vinaygopal

                        When i click a button, i want to open up the python script (.py file) and run the python script written by me and exit python. I should be able to pass arguments to the python file through Qt c++? please help me out on how to achieve this. i did do some reading about QProcess class but i am not able to achieve this.

                        J.HilkJ Offline
                        J.HilkJ Offline
                        J.Hilk
                        Moderators
                        wrote on last edited by J.Hilk
                        #24

                        @vinaygopal how dead set are you on Python as the scripting language?

                        If it's not dictated and just a random selection, I'll want to offer 2 alternatives

                        https://doc.qt.io/qt-5/qscriptengine.html#details
                        and
                        https://doc.qt.io/qt-5/qjsengine.html#details

                        for QScript and JavaScript respectively, no external libs required


                        Be aware of the Qt Code of Conduct, when posting : https://forum.qt.io/topic/113070/qt-code-of-conduct


                        Q: What's that?
                        A: It's blue light.
                        Q: What does it do?
                        A: It turns blue.

                        1 Reply Last reply
                        0
                        • JonBJ Offline
                          JonBJ Offline
                          JonB
                          wrote on last edited by JonB
                          #25

                          @vinaygopal said in embed a python function into my Qt App.:
                          @vinaygopal originally wrote just:

                          i want to open up the python script (.py file) and run the python script written by me and exit python. I should be able to pass arguments to the python file through Qt c++? please help me out on how to achieve this. i did do some reading about QProcess class but i am not able to achieve this.

                          If that is indeed all he wants to do, he may not need any integrated scripting, he may just need to make his QProcess attempt work and we would be done....

                          If he would say why/what the script is supposed to do which requires embedding, we would all know what is required....

                          1 Reply Last reply
                          0
                          • JonBJ JonB

                            I'm keeping an eye on this thread. As I said right at the start

                            You can indeed go down @jsulm's path, but embedding is a lot more involved than just running a subprocess.
                            But as phrased if all you want to do is run an external script with some command-line arguments [...], it really is simple to do with QProcess, should take one minute to write.

                            I do hope/presume that (for both your sakes) for use case here all this embedding is indeed required and worth the effort! :)

                            V Offline
                            V Offline
                            vinaygopal
                            wrote on last edited by
                            #26

                            @JonB @jsulm @J-Hilk ok alright! i give up on embedding python into my program! it just doesn't seem to work however this is the reason for me to use Python, i have a file in my local desktop and i have to send it to the cloud and make the image uploaded a public image these cases can be easily achieved using python if i have to do it with javascript i will have to do it using node JS which will complicate the app, so from QProcess i am able to open the python file inside the python file i have a function called upload blob and it takes two arguments how do i call this function blob and pass those 2 arguments to them using QProcess().

                            My C++ code

                                QApplication a(argc, argv);
                                qDebug()<<"working"<<endl;
                                int result=QProcess::execute("C:/Users/vinay/AppData/Local/Programs/Python/Python38/python.exe",QStringList("C:/Users/vinay/Documents/first_qml_training/example_project/upload_to_cloud.py")<<"C:/Users/vinay/Documents/python folder/player1.png"<<"tank.png");
                                qDebug()<<result<<endl;
                            

                            My python function

                            #!/usr/bin/env python
                            # -*- coding: utf-8 -*-
                            from gcloud import storage
                            import os
                            os.environ["GOOGLE_APPLICATION_CREDENTIALS"]="C:/Users/vinay/Downloads/My First Example Project-507e91a5b594.json"
                            
                            def upload_blob(source_file_name, destination_blob_name):
                                """Uploads a file to the bucket."""
                                bucket_name="example_1995"
                                storage_client = storage.Client()
                                bucket = storage_client.get_bucket(bucket_name)
                                blob = bucket.blob(destination_blob_name)
                            
                                blob.upload_from_filename(source_file_name)
                            
                                print('File {} uploaded to {}.'.format(
                                    source_file_name,
                                    destination_blob_name))
                                    
                            print("i am working")
                            

                            "

                            JonBJ 1 Reply Last reply
                            0
                            • V vinaygopal

                              @JonB @jsulm @J-Hilk ok alright! i give up on embedding python into my program! it just doesn't seem to work however this is the reason for me to use Python, i have a file in my local desktop and i have to send it to the cloud and make the image uploaded a public image these cases can be easily achieved using python if i have to do it with javascript i will have to do it using node JS which will complicate the app, so from QProcess i am able to open the python file inside the python file i have a function called upload blob and it takes two arguments how do i call this function blob and pass those 2 arguments to them using QProcess().

                              My C++ code

                                  QApplication a(argc, argv);
                                  qDebug()<<"working"<<endl;
                                  int result=QProcess::execute("C:/Users/vinay/AppData/Local/Programs/Python/Python38/python.exe",QStringList("C:/Users/vinay/Documents/first_qml_training/example_project/upload_to_cloud.py")<<"C:/Users/vinay/Documents/python folder/player1.png"<<"tank.png");
                                  qDebug()<<result<<endl;
                              

                              My python function

                              #!/usr/bin/env python
                              # -*- coding: utf-8 -*-
                              from gcloud import storage
                              import os
                              os.environ["GOOGLE_APPLICATION_CREDENTIALS"]="C:/Users/vinay/Downloads/My First Example Project-507e91a5b594.json"
                              
                              def upload_blob(source_file_name, destination_blob_name):
                                  """Uploads a file to the bucket."""
                                  bucket_name="example_1995"
                                  storage_client = storage.Client()
                                  bucket = storage_client.get_bucket(bucket_name)
                                  blob = bucket.blob(destination_blob_name)
                              
                                  blob.upload_from_filename(source_file_name)
                              
                                  print('File {} uploaded to {}.'.format(
                                      source_file_name,
                                      destination_blob_name))
                                      
                              print("i am working")
                              

                              "

                              JonBJ Offline
                              JonBJ Offline
                              JonB
                              wrote on last edited by JonB
                              #27

                              @vinaygopal
                              Which is why I asked as I did at the start! Really wish you had said!

                              So you simply want to pass some string filenames to a script which does something, right? No need for integrated scripting.

                              You need to tell us what actually happens/goes wrong!

                              First just make your Python script print out everything in sys.argv so we can see.

                              Oh, I see, you haven't twigged that at all. You can't just write a function in a standalone Python script/program. You need to have a main program in your script, and access argv for the command-line arguments!

                              import sys
                              # Main entry point of app
                              if __name__ == "__main__":
                                  # args = sys.argv
                                  # count = len(sys.argv)
                                  while i < len(sys.argv):
                                      arg = sys.argv[i]
                                      print(arg)
                              

                              There are millions of examples on the web.

                              Separately, you'd better hope all your commands etc are happy with those / path separators rather than native \. I don't want to debate this again with others: some Windows stuff is happy with /, some is not.

                              V 1 Reply Last reply
                              3
                              • JonBJ JonB

                                @vinaygopal
                                Which is why I asked as I did at the start! Really wish you had said!

                                So you simply want to pass some string filenames to a script which does something, right? No need for integrated scripting.

                                You need to tell us what actually happens/goes wrong!

                                First just make your Python script print out everything in sys.argv so we can see.

                                Oh, I see, you haven't twigged that at all. You can't just write a function in a standalone Python script/program. You need to have a main program in your script, and access argv for the command-line arguments!

                                import sys
                                # Main entry point of app
                                if __name__ == "__main__":
                                    # args = sys.argv
                                    # count = len(sys.argv)
                                    while i < len(sys.argv):
                                        arg = sys.argv[i]
                                        print(arg)
                                

                                There are millions of examples on the web.

                                Separately, you'd better hope all your commands etc are happy with those / path separators rather than native \. I don't want to debate this again with others: some Windows stuff is happy with /, some is not.

                                V Offline
                                V Offline
                                vinaygopal
                                wrote on last edited by vinaygopal
                                #28
                                This post is deleted!
                                JonBJ 1 Reply Last reply
                                0
                                • V vinaygopal

                                  This post is deleted!

                                  JonBJ Offline
                                  JonBJ Offline
                                  JonB
                                  wrote on last edited by JonB
                                  #29

                                  @vinaygopal
                                  Why in the world would you try to access sys.argv[4:5] if you have said there 3 arguments?

                                  Please copy my code and run, then you will see your args are sys.argv[1:3]. You can pass those as appropriate to any functions you write.

                                  Yes, you are already passing your arguments on the command line from your C++ QProcess::execute() call.

                                  Please do a little printing/debugging yourself to discover this.

                                  V 1 Reply Last reply
                                  0
                                  • JonBJ JonB

                                    @vinaygopal
                                    Why in the world would you try to access sys.argv[4:5] if you have said there 3 arguments?

                                    Please copy my code and run, then you will see your args are sys.argv[1:3]. You can pass those as appropriate to any functions you write.

                                    Yes, you are already passing your arguments on the command line from your C++ QProcess::execute() call.

                                    Please do a little printing/debugging yourself to discover this.

                                    V Offline
                                    V Offline
                                    vinaygopal
                                    wrote on last edited by
                                    #30

                                    @JonB sorry! i wasn't able to understand the code flow i made that comment thank you so much. this was such a fun ride.

                                    i was able to achieve what i wanted to do. this forum is really helpful.

                                    Thank you.

                                    JonBJ 1 Reply Last reply
                                    2
                                    • V vinaygopal

                                      @JonB sorry! i wasn't able to understand the code flow i made that comment thank you so much. this was such a fun ride.

                                      i was able to achieve what i wanted to do. this forum is really helpful.

                                      Thank you.

                                      JonBJ Offline
                                      JonBJ Offline
                                      JonB
                                      wrote on last edited by JonB
                                      #31

                                      @vinaygopal
                                      I am glad we have helped you :)

                                      Let me say one thing about asking questions here. As I have mentioned, you came in saying "QProcess doesn't work" and then pursued embedding, which as I suspected turned out to be a lot of work. Yet you did not need that, and could have had the QProcess solution in 5 minutes.

                                      The moral is: it is usually worth explaining here exactly what you are actually trying to achieve in a few words, rather than "how do I embed" or similar-ish (unless you really know what you are talking about!). Often questions like that actually assume the wrong approach. The experts here will see your description and may save you a lot of time by proposing a simple method to achieve your goal.

                                      V 1 Reply Last reply
                                      2
                                      • JonBJ JonB

                                        @vinaygopal
                                        I am glad we have helped you :)

                                        Let me say one thing about asking questions here. As I have mentioned, you came in saying "QProcess doesn't work" and then pursued embedding, which as I suspected turned out to be a lot of work. Yet you did not need that, and could have had the QProcess solution in 5 minutes.

                                        The moral is: it is usually worth explaining here exactly what you are actually trying to achieve in a few words, rather than "how do I embed" or similar-ish (unless you really know what you are talking about!). Often questions like that actually assume the wrong approach. The experts here will see your description and may save you a lot of time by proposing a simple method to achieve your goal.

                                        V Offline
                                        V Offline
                                        vinaygopal
                                        wrote on last edited by
                                        #32

                                        @JonB got it thanks will keep this in mind :)

                                        1 Reply Last reply
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