py-subcommands

Introduction

This is a python modules for sub-commands CLI with bash autocomplete.

Sub-commands are useful for minimizing name collisions between executables. For example, instead of having several executables in path such as my-app-init, my-app-run, my-app-list, etc, we can have a single executable my-app with init, run and list as its subcommands, eg: my-app init.

With this library, each sub-command would be coded as individual script under a module path. The library only consists of a single Python module file, and this module file can be dropped to any of python library path to be used directly.

Quick Start

To use the library, create a python main script (that are accessible from PATH), such as the following my-app.py script:

#!/usr/bin/env python3
# PYTHON_ARGCOMPLETE_OK

from subcommands import SubCommands

if __name__ == '__main__':

        SubCommands(
                modules=['my_app.cmds'],
        ).main()

# EOF

Run the argcomplete command to register my-app.py script for tab-completion:

eval "$(register-python-argcomplete ngs-pl)"

Alternatively, active the global completion by running the following command:

activate-global-python-argcomplete

In my_app/cmds directory, create the sub-command script, such as the following init_data.py script:

# this script implement init-data command

import argparse

def init_argparser():

        p = argparse.ArgumentParser()
        p.add_argument('infile')
        return p

def init_data(args):
        print('Initializing data...')

def main(args):
        init_data(args)

# EOF

The init-data sub-command can now be executed as following:

my-app.py init-data