Deeply nested subcommands in Node CLIs with Commander.js

For a recent project I was leveraging the awesome Commander.js framework to build out a CLI with a ton of commands and subcommands.

Example: Fast-food CLI

Let's say you're building a CLI to order food from a fast food restaurant with the following interface:

Program overview:
  $ mcd

Order some food:
  $ mcd order

Order a burger menu:
  $ mcd order burger

Order some dessert:
  $ mcd order dessert

Pay a meal:
  $ mcd pay

File structure

With Commander.js, you can easily implement above interface using the following file structure:

cli/
    mcd
    mcd-order
    mcd-order-burger
    mcd-order-dessert
    mcd-pay

😍 Note how neatly self-documenting this file structure is.

Each of these files is a standalone executable and could be used on its own (don't forget to run chmod +x cli/*).

Code

The most top-level program (mcd) will declare its subcommand order.

#!/usr/bin/env node
const { program } = require('commander')

// mcd-order
program.command('order', 'Order some food')

program.action(() => {
	program.help()
})

program.parse(process.argv)

Important: program.command must be invoked with the second argument (description), as this will hint to Commander that the subcommand lives in its own executable.

The subcommand mcd-order will declare its own subcommands using the same syntax:

#!/usr/bin/env node
const { program } = require('commander')

program
	// mcd-order-burger
	.command('burger', 'Order a burger menu')
	// mcd-order-dessert
	.command('dessert', 'Order some dessert')

program.action(() => {
	program.help()
})

program.parse(process.argv)

And finally, at the end of the chain, mcd-order-burger does not declare any more subcommands:

#!/usr/bin/env node
const { program } = require('commander')

program.action(() => {
	console.log('Thank you for ordering some burgers!')
})

program.parse(process.argv)

And that's how you can deeply nest subcommands for your Node.js CLI using Commander.js!

For a complete reproducible example, check out the repository on GitHub.