Python dependencies between groups using argparse

Question

I started to learn Python, and now I\'m learning the great benefits of argparse. Using argparse, I have created two groups of arguments: group_li

Answer 1

You can use a common mutually-exclusive-group as "root" of the two subgroups:

import argparse
parser = argparse.ArgumentParser(
        description='this is the description',
        epilog="This is the epilog",
        argument_default=argparse.SUPPRESS  
        )

parser.add_argument('-v', '--verbose', help='verbose', action='store_true', default=False)

root_group = parser.add_mutually_exclusive_group()

group_list = root_group.add_mutually_exclusive_group()
group_list.add_argument('-m', help='list only modules', action='store_const', dest='list', const='modules', default='all')
group_list.add_argument('-p', help='list only ports', action='store_const', dest='list', const='ports', default='all')
group_list.add_argument('--list', help='list only module or ports', choices=['modules','ports'], metavar='', default='all')

group_simulate = root_group.add_mutually_exclusive_group()
group_simulate.add_argument('-M', help='simulate module down', nargs=1, metavar='module_name', dest='simulate')
group_simulate.add_argument('-P', help='simulate FC port down', nargs=1, metavar='fc_port_name', dest='simulate')
group_simulate.add_argument('-I', help='simulate iSCSI port down', nargs=1, metavar='iSCSI_port_name', dest='simulate')
group_simulate.add_argument('--simulate', help='simulate module or port down', nargs=1, dest='simulate')

args = parser.parse_args()

print args

Result:

$ python test.py -m -P asfafs
usage: test.py [-h] [-v] [[-m | -p | --list ]
                [-M module_name | -P fc_port_name | -I iSCSI_port_name | --simulate SIMULATE]
test.py: error: argument -P: not allowed with argument -m 

$ python test.py -m -p
usage: test.py [-h] [-v] [[-m | -p | --list ]
                [-M module_name | -P fc_port_name | -I iSCSI_port_name | --simulate SIMULATE]
test.py: error: argument -p: not allowed with argument -m