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Currently I have config.py in my package and I can access variables defined in config.py from other py files as 

import config
var1 = config.var1

First of all, Can I pass file as argument? test.py config.py

But is there way to pass config file through command line as argument and access the variables defined in it? I see there is sys module to get arguments passed through command line. But can I get variables defined in passed file?

edit Now I am able to access variables in passed file as __import__(sys.argv[1]) and called python test.py config. But can I call config.py file by giving pythonpath? e/g/ python test.py ~/Desktop/config or PYTHONPATH='~/Desktop/' python test.py config? Because if I do this I get no module error.

user2661518
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    Are you referring to command-line parameters, like `my_script.py a=1 b=abc d=1,23,5`? – xtofl Jan 04 '16 at 17:47
  • Look at this topic http://stackoverflow.com/questions/301134/dynamic-module-import-in-python – Ivan Velichko Jan 04 '16 at 17:49
  • Just get the file name from sys.argv, then import the file and access the variables. – Chad S. Jan 04 '16 at 17:50
  • @ChadS. I tried sys.argv but I get error `import by filename is not supported` I tried `__import__(sys.argv[1])` and passed `python test.py ./config.py` – user2661518 Jan 04 '16 at 18:20
  • @user2661518: What if you strip off the path prefix and the py suffix? Also, why not store the variables in a language agnostic way (e.g. JSON or XML) and use a Python library to read the variables from the file? –  Jan 04 '16 at 18:25
  • @DavidCullen Is there any specific library to read variables from file? – user2661518 Jan 04 '16 at 18:31
  • got it ! I ran it as `python test.py config` But how can call config file through path? e.g. `python test.py ~/Desktop/config` – user2661518 Jan 04 '16 at 18:42
  • Maybe what you want is https://docs.python.org/2/library/configparser.html –  Jan 04 '16 at 20:23

1 Answers1

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What you do with import config is make all names from config.py available in your script.

You can do this using __import__(sys.args[1]) like stated in answers to this question.

But for actual program configuration, sure do take a look at the argparse module!

p = argparse.ArgumentParser(description="...")
p.add_argument("--var1", type=int)
p.add_argument("--var2", type=str)

config = p.parse_args() # will look at sys.args by default

if config.var1 > 10:
    ....
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xtofl
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  • With `argparse` you can't pass the file, right? I tried sys.argv but I get error `import by filename is not supported` I tried `__import__(sys.argv[1])` and passed python test.py ./config.py – user2661518 Jan 04 '16 at 18:16
  • got it ! I ran it as `python test.py config` But how can call config file through path? e.g. `python test.py ~/Desktop/config` – user2661518 Jan 04 '16 at 18:42
  • On windows, you can `set PATH=%PATH%;c:/dir/with/script`, and then you can run your script from anywhere. – xtofl Jan 05 '16 at 05:52