JSPM – csso@1.5.2

Package Exports

csso
csso/package.json

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (csso) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

CSSO (CSS Optimizer) is a CSS minimizer unlike others. In addition to usual minification techniques it can perform structural optimization of CSS files, resulting in smaller file size compared to other minifiers.

Install

npm install -g csso

Usage

Command line

csso [input] [output] [options]

Options:

      --debug [level]      Output intermediate state of CSS during compression
  -h, --help               Output usage information
  -i, --input <filename>   Input file
  -o, --output <filename>  Output file (result outputs to stdout if not set)
      --restructure-off    Turns structure minimization off
      --stat               Output statistics in stderr
  -v, --version            Output version

Some examples:

> csso in.css out.css

> csso in.css
...output result in stdout...

> echo ".test { color: #ff0000; }" | csso
.test{color:red}

> cat source1.css source2.css | csso | gzip -9 -c > production.css.gz

Debug and statistics:

> echo '.test { color: #ff0000 }' | node bin/csso --stat >/dev/null
File:       <stdin>
Original:   25 bytes
Compressed: 16 bytes (64.00%)
Saving:     9 bytes (36.00%)
Time:       12 ms
Memory:     0.346 MB

> echo '.test { color: green; color: #ff0000 } .foo { color: red }' | node bin/csso --debug
## parsing done in 10 ms

Compress block #1
(0.002ms) convertToInternal
(0.000ms) clean
(0.001ms) compress
(0.002ms) prepare
(0.000ms) initialRejoinRuleset
(0.000ms) rejoinAtrule
(0.000ms) disjoin
(0.000ms) buildMaps
(0.000ms) markShorthands
(0.000ms) processShorthand
(0.001ms) restructBlock
(0.000ms) rejoinRuleset
(0.000ms) restructRuleset
## compressing done in 9 ms

.foo,.test{color:red}

> echo '.test { color: green; color: #ff0000 } .foo { color: red }' | node bin/csso --debug 2
## parsing done in 8 ms

Compress block #1
(0.002ms) convertToInternal
  .test{color:green;color:#ff0000}.foo{color:red}

(0.000ms) clean
  .test{color:green;color:#ff0000}.foo{color:red}

(0.001ms) compress
  .test{color:green;color:red}.foo{color:red}

...

(0.002ms) restructBlock
  .test{color:red}.foo{color:red}

(0.001ms) rejoinRuleset
  .foo,.test{color:red}

(0.000ms) restructRuleset
  .foo,.test{color:red}

## compressing done in 13 ms

.foo,.test{color:red}

API

var csso = require('csso');

var compressed = csso.minify('.test { color: #ff0000; }');
console.log(compressed);
// .test{color:red}

// there are some options you can pass
var compressedWithOptions = csso.minify('.test { color: #ff0000; }', {
    restructuring: false, // don't change css structure, i.e. don't merge declarations, rulesets etc
    debug: true           // show additional debug information:
                          // true or number from 1 to 3 (greater number - more details)
});

// you may do it step by step
var ast = csso.parse('.test { color: #ff0000; }');
ast = csso.compress(ast);
var compressed = csso.translate(ast, true);
console.log(compressed);
// .test{color:red}

Documentation

May be outdated