@udes/shelljs-nodecli

ShellJS Node CLI Extension (UdeS version)

An extension for ShellJS that makes it easy to find and execute Node.js CLIs.

The difference between the original package and this version is that the module will also searches inside the node_modules of your CLI.

So, this module will searches as the following way:

• node_modules of the project where your CLI is installed or where you actually execute a command of your CLI;
• global node_modules;
• node_modules of your CLI if it's installed globally.

The Problem

ShellJS is a fantastic tool for interacting with the shell environment in a cross-platform way. It allows you to easily write scripts that would otherwise be written in bash without worrying about compatibility.

The only problem is that it's a real pain to execute Node binaries that are installed locally. Most end up manually looking into the node_modules directory to find the binary file to execute directly with Node, especially when working on Windows, where the files in node_modules/.bin tend not to work from scripting environments like make and ShellJS. Consequently, you end up seeing a lot of this:

import shell from 'shelljs'

const ESLINT = 'node_modules/eslint/bin/eslint.js'

shell.exec(`node ${ESLINT} myfile.js`)

The Solution

Since Node binaries are specified in their package.json files, it's actually pretty easy to look up the location of the runtime file and get the path. That's where the ShellJS Node CLI extension comes in:

import ShellJSNodeCLI from '@udes/shelljs-nodecli'

ShellJSNodeCLI.exec('eslint myfile.js')

The nodeCLI utility has its own exec() that is specifically for use when executing Node CLIs. It searches through the working directory's node_modules directory to find a locally installed utility. If it's not found there, then it searches globally. Finally, it will searches inside the node_modules of your CLI. If it's still not found, then an error is thrown.

You can pass in as many string arguments as you'd like, and they will automatically be concatenated together with a space in between, such as:

import ShellJSNodeCLI from '@udes/shelljs-nodecli'

ShellJSNodeCLI.exec("eslint -f compact myfile.js");

This ends up creating the following string:

eslint -f compact myfile.js

This frees you from needing to do tedious string concatenation to execute the command.

The exec() method otherwise behaves exactly the same as the default ShellJS exec() method, meaning you can use the same options and callback arguments, such as:

import ShellJSNodeCLI from '@udes/shelljs-nodecli'

const version = ShellJSNodeCLI.exec('eslint -v', {silent:true}).output;

const child = ShellJSNodeCLI.exec('some_long_running_process', {async:true})
child.stdout.on('data', (data) => {
    /* ... do something with data ... */
})

ShellJSNodeCLI.exec('some_long_running_process', (code, output) => {
    console.log('Exit code:', code)
    console.log('Program output:', output)
})

Copyright

• Copyright 2014 Nicholas C. Zakas. All rights reserved.
• Copyright 2017 Université de Sherbrooke. All rights reserved.

License

MIT License