argh!

argh is an extremely light weight options or process.argv parser for node.js. It only includes the bare minimal to parse options. It's not a full blown cli library, but it can be used as a dependency of a cli library to do all the heavy lifting.

argh was born out of rage, every cli library that we've found did more than they advertised and added unneeded bloat to what we were trying to achieve... and that was argument parsing. Tiny modules should only focus on one thing and do that one thing really well.

Installation

npm install argh --save

Usage

argh has two functions:

1. A simple parser interface for custom option parsing using argh(..)
2. A lazy loaded parsed results for the process.argv using argh.argv

var argh = require('argh');

// You can directly access the parsed arguments of the node process through
console.log(argh.argv);

// This the same result as running
console.log(argh(process.argv));

So what is supported?

• --arg or -a Is transformed to a boolean (true) if no value is given
• -abc Is transformed to multiple booleans.
• --no-arg, --disable-arg Is transformed to a boolean (false)
• -no-abc, --disable-abc Is transformed to multiple booleans (false)
• --foo bar, --foo="bar", --foo='bar' or --foo=bar Is all transformed to key / value pairs. Where foo is the key and bar the value
• --port 1111 Automatically transforms the string 1111 in a number
• --beer true As you might have guessed it, it's transformed into a boolean
• -- Can be used as an indicator to stop parsing arguments.

Examples

Everybody likes examples, let's assume that the following code is stored as parse.js:

var argv = require('argh').argv;

console.log(argv);

Parsing a single argument:

$ node parse.js --foo

{ foo: true }

Parsing multiple arguments:

$ node parse.js --foo bar --bar='baz'

{ foo: 'bar', bar: 'baz' }

Parsing multiple boolean arguments:

$ node parse.js --foo --no-bar -s --no-f

{ foo: true,
  bar: false,
  s: true,
  f: false }

Parsing multiple short arguments:

$ node parse.js -abc -no-def

{ a: true, b: true, c: true, d: false, e: false, f: false }

Parsing different values:

$ node parse.js --awesome true --port 1111

{ awesome: true, port: 1111 }

Combining arguments in to an object:

$node parse.js --redis.port 8080 --redis.host localhost

{ redis: { port: 8080, host: 'localhost' }

Handling rest arguments:

$ node parse.js --argh --is --awesome -- 1111 --pewpew aaarrgghh

{ argh: true,
  is: true,
  awesome: true,
  argv: [ '1111', '--pewpew', 'aaarrgghh' ] }

All unknown arguments are also directly pushed in to the argv property:

$ node parse.js --foo 111 bar unkown --hello world BUUURRRRRNN

{ foo: 111,
  argv: [ 'bar', 'unkown', 'BUUURRRRRNN' ],
  hello: 'world' }

Parsing duplicate flags:

$ node parse.js --item foo --item bar --item baz

{ item: [ 'foo', 'bar', 'baz' ] }

License

MIT