README.md

applause-cli

Super-duper lightweight no-dependency alternative to clap

Inspired by clap. It wasn't quite what I wanted, so I wrote my own :P

This is refactored out of my main PhD codebase, so if you're wondering why there aren't very many commits, that's why.

• Current version:
• API Docs: https://starbeamrainbowlabs.com/code/applause-cli/
• Changelog: https://github.com/sbrl/applause-cli/blob/master/Changelog.md

Install

Install via npm:

npm install applause-cli --save

Usage

Example usage:

"use strict";

import path from 'path';

import CliParser from 'applause-cli';

// HACK: Make sure __dirname is defined when using es6 modules. I forget where I found this - a PR with a source URL would be great :D
const __dirname = import.meta.url.slice(7, import.meta.url.lastIndexOf("/"));

// Locate your package.json - this assumes it's sitting in the parent directory of this file (e.g. if this file was ./src/index.json and it was at ./package.json)
const package_json_filepath = path.resolve(__dirname, "../package.json");

// Create a new CLI parser
// The name description, version number, etc are all populated from there
const cli = new CliParser(package_json_filepath);

cli.argument("foo", "This is a global argument.", true, "boolean")

cli.subcommand("do_stuff", "Do some stuff.")
	// An argument just for this subcommand
	.argument("input", "The input file to do stuff with.", "default_value_here", "string");

console.log(
	cli.parse(process.argv.slice(2))
);

The full API documentation can be found here: https://starbeamrainbowlabs.com/code/applause-cli/.

Argument Types

Several argument types are currently supported. They are specified as the 4th argument to the .argument() command (either globally or on a specific subcommand):

Type	Meaning
string	Just a string.
integer	An integer (parseInt(value, 10) is used)
float	A floating-point number (parseFloat(value) is used)
boolean	A boolean true/false value. Unlike other types, arguments with this type do not take an explicit value on the cli (e.g. --foo bar) - rather their presence on the CLI sets the value to true. This can be overridden though with argument.has_value = true.
date	Parse the string as a date with new Date(value)
<function>	Pass a function to do custom parsing. The function provided will be called with a single argument - the value that needs parsing. The return value will be considered the parsed value.

In addition, a function can be passed instead of a string defining the type of an argument, and that function will be called with a single argument to parse values instead:

// .....
cli.argument("foo", "An example argument --foo", 128, function(value) {
	// Parse the value as an int and double it before returning
	return parseInt(value, 10) * 2;
});

Read-world use

• I'm using it for the main Node.js application for my PhD in Computer Science!
• terrain50-cli - also developed as part of my PhD
• nimrod-data-downloader - another component of my PhD
• (Are you using this project? Get in touch by opening an issue)

Contributing

Contributions are welcome as PRs! Don't forget to say that you donate your contribution under the Mozilla Public License 2.0 in your PR comment.

Licence

This project is licensed under the Mozilla Public License 2.0. See the LICENSE file in this repository for the full text.