Question

I’m writing a new CLI with pyton and using cmd and argparse libraries. When i set a argument and call it with a long text option it does not recognize it was a text and throws an exception.

Here is how i use arguments:

WACP:~ cli$ add -t group -n NameForNewGroup -desc 'Description for new group' -c 2

Response is:

unrecognized arguments: - t   g r o u p   - n   N a m e F o r N e w G r o u p   - d e s c   ' D e s c r i p t i o n   f o r   n e w   g r o u p '   - c   2

Here how i add arguments:

self.parser.add_argument('-t', '--type',
                                 dest='type',
                                 help=Language.MSG_ADD_TYPE_HELP,
                                 action='store',
                                 default='device'
)
self.parser.add_argument('-c', '--config',
                                 dest='config',
                                 help=Language.MSG_ADD_GROUP_HELP,
                                 action='store',
                                 default=0
)
self.parser.add_argument('-n', '--name',
                                 dest='name',
                                 help=Language.MSG_ADD_NAME_HELP,
                                 action='store',
                                 default='New Device'
)
self.parser.add_argument('-desc', '--description',
                                 dest='description',
                                 help=Language.MSG_ADD_DESC_HELP,
                                 type=complex,
                                 action='store',
                                 default='Default description for device or group included in configuration values')

I looked argparse documentation and did not configure how it could be.

I have to handle this long text parsing and make it work.

Is there anyone has an idea to solve that?

Answer 1

Works for me. Maybe you can produce a minimal test case? What version of Python? Are you sure you’re using argparse and not optparse? Are you calling parse_args() on the right object? What’s the output of -h?

import argparse
p = argparse.ArgumentParser()
p.add_argument('-t', '--type',
               dest='type')
p.add_argument('-c', '--config',
               dest='config')
p.add_argument('-n', '--name',
               dest='name')
p.add_argument('-desc', '--description',
               dest='description')
print(p.parse_args())

When run:

$ python test.py -t group -n NameForNewGroup -desc 'Description for new group' -c 2
Namespace(config='2', description='Description for new group', name='NameForNewGroup', type='group')
$ python test.py -h
usage: test.py [-h] [-t TYPE] [-c CONFIG] [-n NAME] [-desc DESCRIPTION]

optional arguments:
  -h, --help            show this help message and exit
  -t TYPE, --type TYPE
  -c CONFIG, --config CONFIG
  -n NAME, --name NAME
  -desc DESCRIPTION, --description DESCRIPTION

Note

1. Normally, if you have short (e.g. -t) and long (e.g. --type) arguments, the short arguments should be one character each. So -desc is a bit weird.

2. You don’t want type=complex. The complex type is used for complex numbers, such as 1+0.5j.

3. The default action is store, so you can omit it.