embed a python function into my Qt App.

[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! :)

[jsulm]

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

• Delete build directory
• Run qmake
• build

[J.Hilk]

@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

[JonB]

@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....

[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")

"

[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.

[vinaygopal]

This post is deleted!

[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.

[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.

[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.

[vinaygopal]

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