cli-builder

A design pattern for creating CLI tools in python.

prog is the main executable code has a few key attributes:

__init__ file loads the program modules and classes and indexes them in a dictionary. You should also update the program name, description and basic usage here.

from prog.command1 import Command1
from prog.command2 import Command2

name = 'My Prog'
description = 'An example of building a python CLI'
usage = 'prog <command> [<args>]'
version = '0.0.1'

model = {
    'command1': Command1,
    'command2': Command2
}

To add more or change the names of the sub-commands you will need to update the model and the import statements in __init__.py_

Each sub-command has a python module file with the same name and defines a class. It is intended to be with a 1:1 mapping of module:class definition. Here you can see the two example files command1.py and command2.py. When you want to create a new CLI sub-command you can use one of these as the template.

You can test this design pattern by using python3 prog_cli.py command1 --arg1 within this project directory for example:

(general) CUNNINGR-M-X436:cli-builder cunningr$ python3 prog_cli.py command1 --arg1 WOW --arg2 NOW
                      __  __         ____
                     |  \/  |_   _  |  _ \ _ __ ___   __ _
                     | |\/| | | | | | |_) | '__/ _ \ / _` |
                     | |  | | |_| | |  __/| | | (_) | (_| |
                     |_|  |_|\__, | |_|   |_|  \___/ \__, |
                             |___/                   |___/

2021-03-23 12:53:44,485 - INFO - main.prog.command1 - Executing command1 with --arg1: WOW
2021-03-23 12:53:44,485 - INFO - main.prog.command1 - --arg2: NOW

The setup.py is configured to install a script called prog in the users path that will point to the entrypoint of the prog.cli:main

    entry_points={
        'console_scripts': [
            'prog = prog.cli:main'
        ]
    }

Update this part to suit your program

cunningr/cli-builder

cli-builder