Background

There are tons of command-line handling modules but none of them can generate a CLI interface for a very simple function like this without duplicating the existing code and without making the function from other modules unusable:

def add(one, two=4, three=False):
        ''' description
        one: description
        two: description
        three: description
        '''

Best solution I could find is entrypoint, but there is no link to development site, so I forked the project. The only big disadvantage of entrypoint: it destroys the function signature, therefore the function can not be called from other modules.

Goals

• the decorated function should have the same behavior as without the entrypoint2 decorator
• generate CLI parameters from function signature
• generate CLI documentation from python documentation
• boolean parameters should be toggle flags
• generate short flags from long flags: --long -> -l
• automatic --version flag

Similar projects

• entrypoint
• plac
• baker
• argh
• opster

Features

Additional features over original entrypoint:

• function signature is preserved so it can be called both from command-line and external module
• function name, doc and module are preserved so it can be used with sphinx autodoc
• sphinx autodoc documentation style is supported: :param x: this is x
• automatic --version flag, which prints version variable from the current module (__version__, VERSION, ..)
• automatic --debug flag, which turns on logging
• short flags are generated automatically (e.g. --parameter -> -p)
• unit tests

Known problems:

• Python 3 is not supported
• there are more decorators in the module inherited from original entrypoint, but only @entrypoint is tested.
• Autocompletion is not supported

Basic usage

Example:

from entrypoint2 import entrypoint

__version__ = '3.2'

@entrypoint
def add(one, two=4, three=False):
    ''' This function adds three numbers.

    one: first number to add
    two: second number to add
    '''

Generated help:

$ python -m entrypoint2.examples.hello --help
usage: hello.py [-h] [-t TWO] [--three] [--version] [--debug] one

This function adds two number.

positional arguments:
  one                first number to add

optional arguments:
  -h, --help         show this help message and exit
  -t TWO, --two TWO  second number to add
  --three
  --version          show program's version number and exit
  --debug            set logging level to DEBUG

Printing version:

$ python -m entrypoint2.examples.hello --version
3.2

Installation

# as root
easy_install entrypoint2

# as root
pip install entrypoint2

sudo apt-get install python-setuptools
sudo easy_install entrypoint2

# as root
pip uninstall entrypoint2