arguments 18

Argument parser based on docopt

Argument parser based on docopt

install

pip install arguments

usage

Docopt is used for parsing the docstring (doc), arguments bundles the schema parser and returns a OptionParser like object with normalized attributes

For example

arguments test

Usage:
  tests.py <posarg1> <posarg2>

Options:
  -h --help                     Show this screen.
  -o --option=<option1>         An option.
  --option2=<option2>           An option [default: hello].
  -p --parameter=<parameter>    Folder to check the git repos out [default: 77].
  -v --verbose                  Folder from where to run the command [default: .].

called like

python tests.py pval1 pval2

will when called in python return

>>> myargs = Arguments()
>>> print myargs.posarg1
pyval1

>>> print myargs.posarg2
pyval2

Using schema

Assume you are using docopt with the following usage-pattern:

my_program.py [--count=N] <path> <files>

and you would like to validate that <files> are readable, and that <path> exists, and that --count is either integer from 0 to 5, or None.

this is how you validate it using schema:

>>> from arguments import *

>>> s = Schema({'<files>': [Use(open)],
...             '<path>': os.path.exists,
...             '--count': Or(None, And(Use(int), lambda n: 0 < n < 5))})

>>> args = Arguments(validateschema=s)

>>> args.files
[<open file 'LICENSE-MIT', mode 'r' at 0x...>, <open file 'setup.py', mode 'r' at 0x...>]

>>> args.path
'../'

>>> args.count
3

As you can see, it validated data successfully, opened files and converted '3' to int.