I have created a script using argparse.
The script needs to take a configuration file name as an option, and user can specify whether they need to proceed totally the script or only simulate it.
The args to be passed: ./script -f config_file -s or ./script -f config_file.
It's ok for the -f config_file part, but It keeps asking me for arguments for the -s which is optionnal and should not be followed by any.
I have tried this:
parser = argparse.ArgumentParser()
parser.add_argument('-f', '--file')
#parser.add_argument('-s', '--simulate', nargs = '0')
args = parser.parse_args()
if args.file:
config_file = args.file
if args.set_in_prod:
simulate = True
else:
pass
With the following errors:
File "/usr/local/lib/python2.6/dist-packages/argparse.py", line 2169, in _get_nargs_pattern
nargs_pattern = '(-*%s-*)' % '-*'.join('A' * nargs)
TypeError: can't multiply sequence by non-int of type 'str'
And same errror with '' instead of 0.
As @Felix Kling suggested use action='store_true':
>>> from argparse import ArgumentParser
>>> p = ArgumentParser()
>>> _ = p.add_argument('-f', '--foo', action='store_true')
>>> args = p.parse_args()
>>> args.foo
False
>>> args = p.parse_args(['-f'])
>>> args.foo
True
To create an option that needs no value, set the action [docs] of it to 'store_const', 'store_true' or 'store_false'.
Example:
parser.add_argument('-s', '--simulate', action='store_true')
Source: Stackoverflow.com