@iarna/cli

@iarna/cli

Some simple CLI scaffolding for promise returning applications.

EXAMPLE

require('@iarna/cli')(main)
  .boolean('silent')
  .boolean('exit')
  .version()
  .help()

function main (opts, arg1, arg2, arg3) {
  if (!opts.silent) console.error('Starting up!')
  console.log('Got:', arg1, arg2, arg3)
  if (opts.error) throw new Error('throw')
  return new Promise(resolve => setTimeout(resolve, 10000))
}

WHAT YOU GET

• yargs - The wrapper around the main function returns a yargs object, so you can configure it as usual. The argv object is passed in as the first argument of your entry point function. The rest of your positional arguments are passed in as the remaining function arguments.
• exit without resolving warnings - If your program finishes without resolving its promises (like if it crashes hard or you process.exit, or you just don't resolve the promise ) then we warn about that.
• update-notifier - A default update notifier is setup for your app so users will learn about new versions when you publish them. Your app needs to have a name, version and bin entry in its package.json. (The bin entry needs to have the script using @iarna/cli in it for the update notifier to trigger.)
• If your entry point function rejects then that's reported with a stack trace (if the rejected value has .stack) else with the rejected value and your process will exit with an error code.

WHAT ITS NOT

A full framework for writing cli apps. You'll likely outgrow the error handling pretty fast if this is anything beyond a little one off. This mostly exists to scratch my own itch. I kept on writing this code and I wanted to stop. =D

USAGE

require('@iarna/cli')(entryPointFunction) → yargs

The module itself returns a function that you need to call with the name of your main function. This is the top level function of your program that should return a promise, that when resolved indicates that your program is complete.

Your entry point function should look like this:

main(opts, arg1, arg2, …, argn) → Promise

The first opts argument is yargs.argv and the additional arguments are from argv._, so arg1 === argv._[0], arg2 === argv._[1] and so on.