/\ \  __/\ \/\ \      __/\ \__       /\_ \   __        /\ \__
\ \ \/\ \ \ \ \ \___ /\_\ \ ,_\    __\//\ \ /\_\    ___\ \ ,_\ By: Qodesmith
 \ \ \ \ \ \ \ \  _ `\/\ \ \ \/  /'__`\\ \ \\/\ \  /',__\ \ \/  /'__`\/\`'__\
  \ \ \_/ \_\ \ \ \ \ \ \ \ \ \_/\  __/ \_\ \\ \ \/\__, `\ \ \_/\  __/\ \ \/
   \ `\___x___/\ \_\ \_\ \_\ \__\ \____\/\____\ \_\/\____/\ \__\ \____\\ \_\
    '\/__//__/  \/_/\/_/\/_/\/__/\/____/\/____/\/_/\/___/  \/__/\/____/ \/_/

Purgecss Whitelister

Create whitelists dynamically to include your 3rd party library styles! Supports css, sass, and less.

Why this package?

While rebuilding my personal site in React and using webpack + purgecss-webpack-plugin, I noticed that my 3rd party library, Typer.js (it's really cool - it types things out on the screen like a typewriter), had its styles stripped from the bundle. While it wasn't that big a deal to type out the few class names into a whitelist array, what if that list was huge? What if it was yuuuge? I needed a way to dynamically generate a whitelist of selectors. Boom. purgecss-whitelister was born.

Installation

Via npm:

npm i purgecss-whitelister

Usage

purgecss-whitelister is meant to extract all the selectors used in a file and create an array of names for whitelisting. Works with css, sass, and less! This is very handy when you have a 3rd party library that you don't want annihilated from your bundle.

Pass either a string, a globby string, or an array of either, representing the location(s) of the file(s) you want to completely whitelist.

NOTE: purgecss-whitelister will internally ignore any files that don't have the following extensions: css, sass, scss, less, or pcss.

NOTE: Use the pcss extension with caution. It may or may not work. pcss is a PostCSS file extension but has no official documentation. It's been added to this tool for convenience but YMMV. If anyone has info on the pcss extension, I'm all ears.

const { resolve } = require('path')
const whitelister = require('purgecss-whitelister')
 
// Example 1 - simple string
whitelister('./relative/path/to/my/styles.css')
 
// Example 2 - array of strings
whitelister(['./styles1.css', './styles2.scss'])
 
// Example 3 - globby strings
whitelister('./3rd/party/library/*.less')
 
// Example 4 - array of globby strings
whitelister([
  './node_modules/lib1/*.css',
  './node_modules/lib2/*.scss',
  './node_modules/lib3/*.less'
])
 
// Example 5 - ALL THE THINGS
//
whitelister('./node_modules/cool-library/styles/*.*')

Webpack Example

This is essentially what I'm using in my webpack.config.js file:

const whitelister = require('purgecss-whitelister')
const PurgecssPlugin = require('purgecss-webpack-plugin')
const glob = require('glob-all')
const { resolve } = require('path')
 
const webpackConfig = {
 
  // ...a whole buncha stuffs up here...
 
  plugins: [
    new PurgecssPlugin({
      keyframes: false, // https://goo.gl/bACbDW
      styleExtensions: ['.css'],
      paths: glob.sync([
        resolve(resolve(), 'src/**/*.js'),
        resolve(resolve(), 'src/index.ejs')
      ]),
 
      // `whitelist` needed to ensure Typer classes stay in the bundle.
      whitelist: whitelister('node_modules/typer-js/typer.css');,
      extractors: [
        {
          // https://goo.gl/hr6mdb
          extractor: class AvoidBacktickIssue {
            static extract(content) {
              return content.match(/[A-Za-z0-9_-]+/g) || [];
            }
          },
          extensions: ['js'] // file extensions
        }
      ]
    }),
 
    // ...probably more plugins & things...
  ]
}