In Python I have a module myModule.py where I define a few functions and a main(), which takes a few command line arguments.
I usually call this main() from a bash script. Now, I would like to put everything into a small package, so I thought that maybe I could turn my simple bash script into a Python script and put it in the package.
So, how do I actually call the main() function of myModule.py from the main() function of MyFormerBashScript.py? Can I even do that? How do I pass any arguments to it?
It's just a function. Import it and call it:
import myModule myModule.main()
If you need to parse arguments, you have two options:
Parse them in
main(), but pass in
sys.argv as a parameter (all code below in the same module
def main(args): # parse arguments using optparse or argparse or what have you if __name__ == '__main__': import sys main(sys.argv[1:])
Now you can import and call
myModule.main(['arg1', 'arg2', 'arg3']) from other another module.
main() accept parameters that are already parsed (again all code in the
def main(foo, bar, baz='spam'): # run with already parsed arguments if __name__ == '__main__': import sys # parse sys.argv[1:] using optparse or argparse or what have you main(foovalue, barvalue, **dictofoptions)
and import and call
myModule.main(foovalue, barvalue, baz='ham') elsewhere and passing in python arguments as needed.
The trick here is to detect when your module is being used as a script; when you run a python file as the main script (
python filename.py) no
import statement is being used, so python calls that module
"__main__". But if that same
filename.py code is treated as a module (
import filename), then python uses that as the module name instead. In both cases the variable
__name__ is set, and testing against that tells you how your code was run.