pikud

Create UNIX-style CLI applications in Node

pee-kood - Hebrew (not Danish, although I encourage you to look that up if you want a good laugh) for "command"

Inspired by https://github.com/codegangsta/cli

Installation

$ npm install --save pikud

Usage

A CLI app built with pikud consists of either a single command or unlimited nested commands. Each command can have its own flags. Flags are inherited from parent commands and can be overridden on the child if the child allows the same flag.

Flags

Flags are defined by a FlagSet, which consists of any mix of StringFlag, NumberFlag, or BoolFlag. See below examples.

Multiple

If you set allowMultiple:true when defining a StringFlag or NumberFlag, the flag will be parsed as an array rather than a single value (think Docker's -e flag). For example:

new StringFlag('environment', {
  alias:'e',
  allowMultiple:true
});

$ myapp -e "foo=bar" -e "baz=bing" -e "boop=scoop"

Help

Each command also automatically has a help flag (--help or -h) which will show the command's usage in a nice little table.

Actions

If a command has no sub-commands then it must have an action. The action takes any arguments passed via command line as well as the flags that were parsed. An action can either return a value, in which case that value will be written to the console at the end of execution, OR a Promise. If it returns a Promise, then pikud will handle it asynchronously.

Actions are bound to their commands using Function.call, so you can introspect the command or run this.help() to display the help text.

Examples

Single command

import { Command } from 'pikud';
 
let main = new Command('my-app', {
  action:(args, flags) => {
    console.log('Doing action with args', args, 'flags', flags);
  }
});
 
main.run(process.argv);

$ my-app arg1 arg2 arg3

With flags

import { FlagSet, StringFlag, BoolFlag, NumberFlag, Command } from 'pikud';
 
let main = new Command('my-app', {
  flags:new FlagSet([
    new StringFlag('foo', {
      alias:'f',
      defaultValue:'asdf',
      envVar:'FOO',
      description:'Which foo to use?'
    }),
    new BoolFlag('bar', {
      alias:'b',
      description:'Turn on the bar'
    })
  ]),
  action:(args, flags) => {
    console.log('Doing action with args', args, 'flags', flags);
  }
});
 
main.run(process.argv);

$ my-app -f "asdf" -b arg1 arg2 arg3

Sub commands

import { FlagSet, StringFlag, BoolFlag, NumberFlag, Command } from 'pikud';
 
let main = new Command('my-app', {
  flags:new FlagSet([
    new BoolFlag('foo', {
      alias:'f',
      description:'Turn on the foo'
    }),
    new BoolFlag('bar', {
      alias:'b',
      description:'Turn on the bar'
    })
  ]),
  subCommands:{
    cmd1:new Command('cmd1', {
      description:'Do command 1',
      flags: new FlagSet([
        new StringFlag('baz', {
          alias:'z',
          description:'Tell me the baz'
        })
      ]),
      action:(args, flags) => {
        console.log('Doing cmd 1 with ', args, flags);
      }
    })
  }
});
 
main.run(process.argv);

$ my-app -fb cmd1 --baz "This is the baz value" arg1 arg2 arg3