p-s

aka npm-package-scripts or nps for short

All the benefits of npm scripts without the cost of a bloated package.json and limits of json

Quick Video Intro 📺

Simplify and empower npm scripts with p-s 11:19

The problem

Even though npm scripts have a ton of advantages (learn more), it can grow into an unmaintainable mess in your package.json file. Part of the problem is we're configuring scripts in json which has fundamental issues (like no comments).

This solution

p-s is a package that solves this problem by allowing you to move your scripts to a package-scripts.js file. Because this file is a JavaScript file, you can do a lot more with your project scripts. Here's an example of a package-scripts.js file:

module.exports = {
  scripts: {
    default: 'node index.js',
    lint: 'eslint .',
    test: {
      // learn more about Jest here: https://kcd.im/egghead-jest
      default: 'jest',
      watch: {
        script: 'jest --watch',
        description: 'run in the amazingly intelligent Jest watch mode'
      }
    },
    build: {
      default: 'webpack',
      prod: 'webpack -p',
    },
    validate: 'nps --parallel lint,test,build',
  },
}

Or in case you prefer YAML, here's an example of how that would look in a package-scripts.yml file:

scripts:
    default: node index.js
    lint: eslint .
    test:
        # learn more about Jest here: https://kcd.im/egghead-jest
        default: jest
        watch:
            script: jest --watch
            description: run in the amazingly intelligent Jest watch mode
    build:
        default: webpack
        prod: webpack -p
    validate: nps --parallel lint,test,build

To use p-s, it's recommended that you either install it globally (npm i -g p-s) or add ./node_modules/bin to your $PATH (be careful that you know what you're doing when doing this).

Then you can run:

p-s --help

Which will output:

  Usage: nps [options]

  Options:

    -h, --help                                  output usage information
    -V, --version                               output the version number
    -s, --silent                                Silent nps output
    -p, --parallel <script-name1,script-name2>  Scripts to run in parallel (comma seprated)
    -c, --config <filepath>                     Config file to use (defaults to nearest package-scripts.yml or package-scripts.js)
    -l, --log-level <level>                     The log level to use (error, warn, info [default])
    -r, --require <module>                      Module to preload

Available scripts (camel or kebab case accepted)

lint - eslint .
test - jest
test.watch - run in the amazingly intelligent Jest watch mode - jest --watch
build - webpack
build.prod - webpack -p
validate - nps --parallel lint,test,build

Because p-s is harder to type, it is recommended that you use the alias nps to interact with p-s, which is much easier to type and the rest of the documentation will use nps

Now, to run a script, you can run:

nps lint
nps test.watch
# etc.

But the fun doesn't end there! You can use a prefix:

nps b # will run the build script

And these prefixes can go as deep as you like!

nps b.p # will run the production build script

Cool stuff right? And there's more on the roadmap.

Also check out the examples. You'll find some good stuff in there (including how to deal with windows and other cross-platform issues).

Note: If you don't like installing things globally and don't want to muck with your $PATH (or don't want to require that your co-workers or project contributors to do so), then you can add a single script to your package.json. We recommend that you use the start script because it requires less typing:

package.json

{
  "scripts": {
    "start": "nps"
  }
}

You don't have to use the start script if you don't want. Note that if you're writing a node application, you're likely using nps for starting your server. In that case, you can create a default script which will be run when nps is run without arguments (so effectively it'll work just the same). But if you'd prefer, you can use whatever you wish. For example you could easily create a nps script and do: npm run nps b.

Installation

This module is distributed via npm which is bundled with node and should be installed as one of your project's devDependencies:

npm install --save-dev p-s

global installation

You can install this module globally also (this is recommended):

npm install --global p-s

From here you can use p-s on the command line via one of the installed aliases: nps or p-s.

If you do this, you may also be interested in installing the shell autocompletion script. Do so by running:

nps completion <optionally-your-bash-profile-file>

The bash profile file defaults to ~/.bash_profile for bash and ~/.zshrc for zsh. Special thanks to the omelette package for making this so easy.

Getting started

If you're already using npm scripts, you can get up and going really quickly with the init command:

./node_modules/.bin/nps init

./node_modules/.bin/nps init --type yaml

This will use your package.json scripts to generate a package-scripts.js (respectively a package-scripts.yml) file and update your scripts to utilize the nps binary.

API

CLI

Commands

help

If you have a help script, then your help script will be run. Otherwise, this will output the help.

Note: you can do this with nps --help, but if you're using the start script in your package.json this allows you to run npm start help rather than npm start -- --help

init

As indicated above, this will migrate your npm scripts to package-scripts.

completion

Installs autocompletion functionality into your default bash or zsh configuration. You can override the default by providing a specific file:

nps completion ~/.bashrc

Note: you should probably only do this if you have the package installed globally. In that case you should probably also normally use the nps alias rather than p-s because it's easier to type.

CLI options

-h, --help

Will print out the help you see above (the available scripts are colored 🌈 and come from the config specified/default config).

-s, --silent

By default, nps will log out to the console before running the command. You can add -s to your command to silence this.

-p, --parallel

Run the given scripts in parallel. This enables handy workflows like this:

nps -p lint,build,cover && nps check-coverage && nps report-coverage

-c, --config

Use a different config

nps -c ./other/package-scripts.js lint

Normally, npss will look for a package-scripts.js file and load that to get the scripts. Generally you'll want to have this at the root of your project (next to the package.json). But by specifying -c or --config, nps will use that file instead.

-l, --log-level

Specify the log level to use

-r, --require

You can specify a module which will be loaded before the config file is loaded. This allows you to preload for example babel-register so you can use all babel presets you like.

args

You can pass additional arguments to the script(s) that are being spawned:

nps lint --fix # --fix will be passed on to the lint script

scripts

If you don't use -p (because you don't need parallelism) then you can simply provide the name of the script like so:

nps cover

And you can run multiple scripts in series by providing a comma-separated list:

nps cover,check-coverage

That's all for the CLI.

package-scripts.js

nps expects to your package-scripts.js file to module.exports an object with the following properties:

scripts

This can be an object or a function that returns an object. See the annotated example below for what this object can look like (and different ways to run them):

module.exports = {
  scripts: {
    default: 'echo "This runs on `nps`"', // nps
    // you can assign a script property to a string
    simple: 'echo "this is easy"', // nps simple
    // you can specify whether some scripts should be excluded from the help list
    hidden: {
      script: 'debugging script',
      hiddenFromHelp: true,
    },
    test: {
      default: {
        script: 'jest', // nps test
        description: 'Run tests with jest',
        // your scripts will be run with node_modules/.bin in the PATH, so you can use locally installed packages.
        // this is done in a cross-platform way, so your scripts will work on Mac and Windows :)
        // NOTE: if you need to set environment variables, I recommend you check out the cross-env package, which works
        // great with p-s
      },
      otherStuff: {
        // this one can be executed two different ways:
        // 1. nps test.otherStuff
        // 2. nps test.other-stuff
        script: 'echo "testing other things"',
        description: 'this is a handy description',
      },
    },
    // this one can be executed a few different ways:
    // 1. nps k
    // 2. nps kebab-case
    // 3. nps kebabCase
    'kebab-case': 'echo "kebab-case"',
    series: 'nps simple,test,kebabCase', // runs these other scripts in series
  },
}

nps k # runs nps kebab-case

options

This object is used to configure nps with the following options:

silent

Setting this to true will prevent nps from outputting anything for your script (normally you'll get simple output indicating the command that's being executed). This effectively sets the logLevel to disable.

logLevel

This sets the logLevel of nps.

ENV variables

LOG_LEVEL

By setting LOG_LEVEL environment variable you can control the log level for nps

Log level

Log levels available:

error - errors only
warn - errors and warnings only
info - info, errors, and warnings (default)

FAQ

Why `npm start`?

Just to be clear: You do not have to use the start script. You can use whatever you like. But I recommend using the start. npm scripts are generally run with npm run <script-name>. There are some exceptions to this. For example:

npm run test === npm test === npm t
npm run start === nps

So, while you could use a script called script and run npm run script build, I just think it reads more clearly to just use the start script and run nps build. It's also nice that it's fewer things to type. You could also use the test script and then type even less: npm t build, but thats just... odd.

Note, often servers are configured to run npm start by default to start the server. To allow for this case, you can provide a default script at the root of your scripts which will be run when npm start is run without any arguments. Effectively this will allow you to have a script run when npm start is executed.

Inspiration

This was inspired by a tweet by @sindresorhus.

In the wild

react-component-template uses p-s to implement shareable npm scripts. See then how dependent react-swap can reuse them.

GOTCHAS:

use process.cwd() as the base for all paths
Hypercubed/EventsSpeedTests uses p-s to automate benchmark running and reporting in node and the browser. package-scripts.js enables us to keep our scripts DRY. Combined with grunion allows benchmarks to be run, serially or concurrently, on glob patterns.
SmithersAssistant/Smithers is an electron based personal assistant. Smithers works on multiple platforms. Smithers uses p-s to dynamically find the current platform and execute the dev environment. Now we don't have to manually update the package.json scripts when you are on a different platform!

Contributors

Thanks goes to these people (emoji key):

_{Kent C. Dodds} 💻 📖 🚇 💡 📹 👀	_{David Wells} 💻	_{Abhishek Shende} 💻 ⚠️	_{Rowan Oulton} 💻 📖 ⚠️	_{Gilad Goldberg} 💻	_{Tim McGee} 💻 📖	_{Nik Butenko} 💡 💻
_Tommy 🐛 💻 ⚠️ 👀	_{Jayson Harshbarger} 💡 👀	_{JD Isaacks} 💻 ⚠️	_{Christopher Hiller} 👀	_{Robin Malfait} 💡	_{Eric McCormick} 👀 📖	_{Sam Verschueren} 👀
_{Sorin Muntean} 💻 ⚠️ 📖