rework

What is rework?

Rework is a plugin framework for CSS preprocessing. It allows you to manipulate CSS using JavaScript, providing a way to transform stylesheets with various plugins.

What are rework's main functionalities?

CSS Parsing

Rework can parse CSS strings into an Abstract Syntax Tree (AST), which can then be manipulated programmatically.

const rework = require('rework');
const css = 'body { color: red; }';
const ast = rework(css).toString();
console.log(ast);

CSS Transformation

Rework allows you to transform CSS using plugins. For example, the rework-npm plugin lets you import CSS from npm packages.

const rework = require('rework');
const reworkNPM = require('rework-npm');
const css = '@import "normalize.css";';
const output = rework(css).use(reworkNPM()).toString();
console.log(output);

Vendor Prefixing

Rework can automatically add vendor prefixes to CSS properties using plugins like rework-plugin-prefix.

const rework = require('rework');
const reworkPrefix = require('rework-plugin-prefix');
const css = 'body { display: flex; }';
const output = rework(css).use(reworkPrefix('webkit')).toString();
console.log(output);

Other packages similar to rework

postcss

PostCSS is a tool for transforming CSS with JavaScript plugins. It is more modern and widely used compared to Rework, offering a larger ecosystem of plugins and better performance.

less

Less is a CSS pre-processor that extends the CSS language, adding features like variables, mixins, and functions. Unlike Rework, Less is a full-fledged pre-processor rather than a plugin framework.

sass

Sass is another CSS pre-processor that provides advanced features like variables, nested rules, and mixins. Sass is more feature-rich and has a larger community compared to Rework.

README

rework

CSS manipulations built on node-css, allowing you to automate vendor prefixing, create your own properties, inline images, anything you can imagine!

Installation

with node:

$ npm install rework

or in the browser:

$ component install visionmedia/rework

rework(1)

Usage: rework [options]

Options:

  -h, --help            output usage information
  -V, --version         output the version number
  -v, --vendors <list>  specify list of vendors

for example:

$ rework -v webkit,moz < my.css > my.reworked.css

API

rework(css)

Return a new Rework instance for the given string of css.

Rework#vendors(prefixes)

Define vendor prefixes that plugins may utilize, however most plugins do and should accept direct passing of vendor prefixes as well.

Rework#use(fn)

Use the given plugin fn. A rework "plugin" is simply a function accepting the stylesheet object and Rework instance, view the definitions in ./lib/plugins for examples.

Rework#toString(options)

Return the string representation of the manipulated css. Optionally you may compress the output with .toString({ compress: true })

Plugins

The following plugins are bundled with rework:

.at2x([vendors])

Add retina support for images, with optional vendor prefixes, defaulting to .vendors().

logo {
  background-image: url('/public/images/logo.png')
}

yields:

logo {
  background-image: url('/public/images/logo.png')
}

@media all and (-webkit-min-device-pixel-ratio: 1.5) {
  .logo {
    background-image: url("/public/images/[e-mail]")
  }
}

.prefix(property, [vendors])

Prefix property with optional vendors defaulting to .vendors().

.button {
  border-radius: 5px;
}

yields:

.button {
  -webkit-border-radius: 5px;
  -moz-border-radius: 5px;
  border-radius: 5px;
}

.prefixValue(value, [vendors])

Prefix value with optional vendors defaulting to .vendors().

button {
  transition: height, transform 2s, width 0.3s linear;
}

yields:

button {
  -webkit-transition: height, -webkit-transform 2s, width 0.3s linear;
  -moz-transition: height, -moz-transform 2s, width 0.3s linear;
  transition: height, transform 2s, width 0.3s linear
}

.prefixSelectors(string)

Prefix selectors with the given string.

h1 {
  font-weight: bold;
}

a {
  text-decoration: none;
  color: #ddd;
}

yields:

#dialog h1 {
  font-weight: bold;
}

#dialog a {
  text-decoration: none;
  color: #ddd;
}

.opacity()

Add IE opacity support.

ul {
  opacity: 1 !important;
}

yields:

ul {
  opacity: 1 !important;
  -ms-filter: progid:DXImageTransform.Microsoft.Alpha(Opacity=100) !important;
  filter: alpha(opacity=100) !important
}

.url(callback)

Map url() calls, useful for inlining images as data-uris, converting relative paths to absolute etc.

function rewrite(url) {
  return 'http://example.com' + url;
}

rework(str)
  .use(rework.url(rewrite))
  .toString()

.keyframes([vendors])

Prefix @keyframes with vendors defaulting to .vendors(). Ordering with .keyframes() is important, as other plugins may traverse into the newly generated rules, for example the following will allow .prefix() to prefix keyframe border-radius property, .prefix() is also smart about which keyframes definition it is within, and will not add extraneous vendor definitions.

var css = rework(read('examples/keyframes.css', 'utf8'))
  .vendors(['-webkit-', '-moz-'])
  .use(rework.keyframes())
  .use(rework.prefix('border-radius'))
  .toString()

@keyframes animation {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

yields:

@keyframes animation {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

@-webkit-keyframes animation {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

Example

example.js:

var rework = require('rework')
  , read = require('fs').readFileSync
  , str = read('example.css', 'utf8');

var css = rework(str)
  .vendors(['-webkit-', '-moz-'])
  .use(rework.keyframes())
  .use(rework.prefix('border-radius'))
  .toString()

console.log(css);

example.css:

@keyframes animation {
  from { opacity: 0; border-radius: 5px }
  to { opacity: 1; border-radius: 5px }
}

stdout:

@keyframes animation {
  from {
    opacity: 0;
    border-radius: 5px
  }

  to {
    opacity: 1;
    border-radius: 5px
  }
}

@-webkit-keyframes animation {
  from {
    opacity: 0;
    -webkit-border-radius: 5px;
    border-radius: 5px
  }

  to {
    opacity: 1;
    -webkit-border-radius: 5px;
    border-radius: 5px
  }
}

@-moz-keyframes animation {
  from {
    opacity: 0;
    -moz-border-radius: 5px;
    border-radius: 5px
  }

  to {
    opacity: 1;
    -moz-border-radius: 5px;
    border-radius: 5px
  }
}

Example Plugin

Suppose for example you wanted to create your own properties for positions, allowing you to write them as follows:

#logo {
  absolute: top left;
}

#logo {
  relative: top 5px left;
}

#logo {
  fixed: top 5px left 10px;
}

yielding:

#logo {
  position: absolute;
  top: 0;
  left: 0
}

#logo {
  position: relative;
  top: 5px;
  left: 0
}

#logo {
  position: fixed;
  top: 5px;
  left: 10px
}

This is how you could define the plugin:

var rework = require('rework')
  , read = require('fs').readFileSync;

function positions() {
  var positions = ['absolute', 'relative', 'fixed'];

  return function(style){
    style.rules.forEach(function(rule){
      rule.declarations.forEach(function(decl, i){
        if (!~positions.indexOf(decl.property)) return;
        var args = decl.value.split(/\s+/);
        var arg, n;

        // remove original
        rule.declarations.splice(i, 1);

        // position prop
        rule.declarations.push({
          property: 'position',
          value: decl.property
        });

        // position
        while (args.length) {
          arg = args.shift();
          n = parseFloat(args[0]) ? args.shift() : 0;
          rule.declarations.push({
            property: arg,
            value: n
          });
        }
        
      });
    });
  }
}

var css = rework(read('positions.css', 'utf8'))
  .use(positions())
  .toString()

console.log(css);

License

(The MIT License)

Copyright (c) 2012 TJ Holowaychuk <[e-mail]>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.