npm i -g|-D postcss-cli

postcss [input.css] [OPTIONS] [-o|--output output.css] [-w|--watch]

⚠️ If there are multiple input files, the --dir or --replace option must be passed.

cat input.css | postcss [OPTIONS] > output.css

⚠️ If no input files are passed, it reads from stdin. If neither -o, --dir, or --replace is passed, it writes to stdout.

|Name|Type|Default|Description| |:---|:--:|:-----:|:----------| |-d, --dir|{String}|undefined|Output Directory| |-b, --base|{String}|undefined|Use together with --dir for keeping directory structure.| |-x, --ext|{String}|extname(output)|Output File Extension| |-o, --output|{String}|undefined|Output File| |-r, --replace|{String}|undefined|Replace Input <=> Output| |-p, --parser|{String}|undefined|Custom PostCSS Parser| |-s, --syntax|{String}|undefined|Custom PostCSS Syntax| |-t, --stringifier|{String}|undefined|Custom PostCSS Stringifier| |-w, --watch|{Boolean}|false|Enable Watch Mode| |--poll|{Boolean}|false|Use polling for file watching| |-u, --use|{Array}|[]|PostCSS Plugins| |-m, --map|{Boolean}|{ inline: true }|External Sourcemaps| |--no-map|{Boolean}|false|Disable Sourcemaps| |-e, --env|{String}|process.env.NODE_ENV|Sets $NODE_ENV| |-c, --config|{String}|dirname(file)|PostCSS Config Path postcss.config.js| |-h, --help|{Boolean}|false|CLI Help| |-v, --version|{Boolean}|false|CLI Version|

ℹ️ More details on custom parsers, stringifiers and syntaxes, can be found here.

Config

If you need to pass options to your plugins, or have a long plugin chain, you'll want to use a configuration file.

postcss.config.js

module.exports = {
  parser: 'sugarss',
  plugins: [
    require('postcss-import')({...options}),
    require('postcss-url')({ url: 'copy', useHash: true })
  ]
}

Note that you can not set the from or to options for postcss in the config file. They are set automatically based on the CLI arguments.

Context

For more advanced usage it's recommend to to use a function in postcss.config.js, this gives you access to the CLI context to dynamically apply options and plugins per file

|Name|Type|Default|Description| |:--:|:--:|:-----:|:----------| |env|{String}|'development'|process.env.NODE_ENV| |file|{Object}|dirname, basename, extname|File| |options|{Object}|map, parser, syntax, stringifier|PostCSS Options|

postcss.config.js

module.exports = (ctx) => ({
  map: ctx.options.map,
  parser: ctx.file.extname === '.sss' ? 'sugarss' : false,
  plugins: {
    'postcss-import': { root: ctx.file.dirname }),
    'cssnano': ctx.env === 'production' ? {} : false
  }
})

⚠️ If you want to set options via CLI, it's mandatory to reference ctx.options in postcss.config.js

postcss input.sss -p sugarss -o output.css -m

postcss.config.js

module.exports = (ctx) => ({
  map: ctx.options.map,
  parser: ctx.options.parser,
  plugins: {
    'postcss-import': { root: ctx.file.dirname },
    'cssnano': ctx.env === 'production' ? {} : false
  }
})