gpestana / pipe-args

POSIX compliant pipe argument parser for node CLI apps

pipe-args

pipe-args adds support for unix piped arguments to your node CLI apps

pipe-args makes your node CLI apps to fully support unix pipelines, completely out of the box. Require the the pipe-args module and all the piped arguments are added to the process stdin transparently. It also integrates well with popular command line interface/parsers like yarg and commander.js.

Installation

$ npm install --save pipe-args

Usage

#!/usr/bin/env node

const pipe = require('pipe-args').load();
console.log(`The piped arg is ${process.argv[2]}`);

$ echo test | node index.js

$ The piped arg is test

Options

You can define which commands allow the stdin to be copied to process.argv by passing them in the options object:

#!/usr/bin/env node

const pipe = require('pipe-args').load(['command']);
console.log(`The piped arg is ${process.argv[2]}`);

$ echo OK | node command index.js

$ The piped arg is OK

$ echo OK | node commandNotPiping index.js

$ The piped arg is null // stdin was not parsed into process.argv

Integrations

pipe-args plays along with optstrings parsers such as yarg. The following yargs parser code:

#!/usr/bin/env node

const pipe = require('pipe-args').load();
const yargs = require('yargs')

const cli = yargs.demand(1)

console.log(cli.argv);

parses linux-style piped arguments as expected:

$ echo piped_arg | yargs-cli.js

$ { _: [ 'piped_arg' ], '$0': 'index.js' }

License:

MIT © Gonçalo Pestana