liftoff

What is liftoff?

Liftoff is a lightweight CLI framework that helps you build command-line tools. It provides a way to bootstrap your CLI application with support for configuration files, environment variables, and plugins.

What are liftoff's main functionalities?

Command-line Interface Bootstrapping

This feature allows you to bootstrap a CLI application with Liftoff. The code sample demonstrates how to create a new Liftoff instance and launch it, printing the environment information.

const Liftoff = require('liftoff');
const MyApp = new Liftoff({
  name: 'myapp',
  moduleName: 'myapp',
  configName: 'myappfile',
  extensions: {
    '.js': null
  }
});
MyApp.launch({}, (env) => {
  console.log('MyApp is running!');
  console.log('Environment:', env);
});

Configuration File Support

Liftoff supports loading configuration files. The code sample shows how to load a configuration file if it exists and print its contents.

const Liftoff = require('liftoff');
const MyApp = new Liftoff({
  name: 'myapp',
  configName: 'myappfile',
  extensions: {
    '.js': null
  }
});
MyApp.launch({}, (env) => {
  if (env.configPath) {
    const config = require(env.configPath);
    console.log('Loaded config:', config);
  } else {
    console.log('No config file found.');
  }
});

Environment Variable Support

Liftoff can access and utilize environment variables. The code sample demonstrates how to print all environment variables when the CLI application is launched.

const Liftoff = require('liftoff');
const MyApp = new Liftoff({
  name: 'myapp',
  configName: 'myappfile',
  extensions: {
    '.js': null
  }
});
MyApp.launch({}, (env) => {
  console.log('Environment Variables:', process.env);
});

Other packages similar to liftoff

commander

Commander is a popular package for building command-line interfaces. It provides a simple and flexible way to define commands, options, and arguments. Compared to Liftoff, Commander focuses more on command parsing and less on configuration and environment management.

yargs

Yargs is another powerful library for building CLI applications. It offers extensive features for parsing arguments, generating help messages, and handling commands. Yargs provides more built-in utilities for argument parsing compared to Liftoff, which focuses on bootstrapping and configuration.

oclif

Oclif is a framework for building command-line tools, developed by Heroku. It provides a robust structure for creating complex CLI applications with plugins and command management. Oclif is more opinionated and feature-rich compared to Liftoff, which is more lightweight and flexible.

README

liftoff

Launch your command line tool with ease.

What?

Say you're writing a CLI tool. Let's call it hacker. You want to configure it using a Hackerfile. This is node, so you install hacker locally for each project you use it in. But, in order to get the hacker command in your PATH, you also install it globally.

Now, when you run the hacker command, you want it to use the Hackerfile in your current directory, and the local installation of hacker next to it. It'd be nice if it traversed up your folders until it found a Hackerfile, for those times when you're not in the root directory of your project. Heck, you might even want to launch it from a folder outside of your project by manually specifying a working directory. Liftoff manages this for you.

So, everything is working great. Now you can find your local hacker and Hackerfile with ease. Unfortunately, it turns out you've authored your Hackerfile in coffee-script, or some other JS variant. In order to support that, you have to load the compiler for it, and then register the extension for it with node. Good news, Liftoff can do that too.

Examples

Check out the hacker project to see how you might use this.

Try it now

Want to see how the above example works?

1. Install the sample project hacker with npm install -g hacker
2. Make a Hackerfile.js with some arbitrary javascript it.
3. Run hacker while in the same parent folder.

For extra credit, try writing your Hackerfile in coffeescript. Then, run hacker --require coffee-script. Make sure you install coffee-script locally, though!