Click

Click is a very convenient way to build command line applications in python. Example:

import click


@click.command()
def hello():
    click.echo("Hello world")
    
hello()

This file just became a command line application.

Options & Arguments

A click command can have options and arguments.

Options Are optional. Recommended to use for everything except subcommands, urls, or files. Can take a fixed number of arguments. The default is 1. They may be specified multiple times using Multiple Options. Are fully documented by the help page. Have automatic prompting for missing input. Can act as flags (boolean or otherwise). Can be pulled from environment variables.

Arguments Are optional with in reason, but not entirely so. Recommended to use for subcommands, urls, or files. Can take an arbitrary number of arguments. Are not fully documented by the help page since they may be too specific to be automatically documented. [...] Can be pulled from environment variables but only explicitly named ones. For more see Environment Variables.

It seems that options will be my go o

Packaging

Click has a guide here on how to use setuptools to package the CLI. If you're distributing your package, it's important that you don't rely just on the shebang.

This is what the setup.py would look like:

from setuptools import setup, find_packages

setup(
    name='yourpackage',
    version='0.1.0',
    packages=find_packages(),
    include_package_data=True,
    install_requires=[
        'Click',
    ],
    entry_points={
        'console_scripts': [
            'yourscript = yourpackage.scripts.yourscript:cli',
        ],
    },
)

But, I want to avoid writing setup.py, and use pyproject.toml instead.