python3.7 subprocess failed to delete files for me

I have a python script using ‘subprocess’ running linux command to confirm my task is doing the right thing, and it worked well. But i found that at the same time it will generate some log files when running my task. So i added a clean up function to rm log files for me at the beginning. My script is:

def test_clean_up_logs(path_to_my_log):
    regex = path_to_my_log + ".*"   # i need this because log will append current date time when it's generated
    print(regex) # i can see it's correct
    result = subprocess.run(['rm', '-rf', regex])


def test_my_real_test():
      # This will run my real test and generate log files

but it turns out it did not remove log files for me after i added first test, it still have more and more logs file in my build dir. I run it using:

Python3.7 -m pytest /path/to/mydir

My question is: 1. Why did not it work? In my second test case, i am using ‘subprocess’ to run a linux command and it worked fine.
2. Is this correct way to clean up log files? i cannot think of a better way to do it automatically. Thanks!

Answer

Why did not it work?

Because the arguments that you gave to your command is passed in quotes and wildcards like * does not work in quotes. Currently the executed command looks like this:

$ rm "-rf" "filename.*"

Try this in your terminal and you will see that it will not remove the files that starts with filename..

You need to pass shell = True to execute the command in a shell interpreter and give your command as a single string.

subprocess.run(f'rm -rf {regex}', shell=True)