middleware.md

Connect Middleware

Stylus ships with Connect middleware for auto-compiling Stylus sheets whenever they're modified.

stylus.middleware(options)

Return Connect middleware with the given options.

Options

  `force`     When __true__ styles will always re-compile
  `src`       Source directory used to find .styl files
  `dest`      Destination directory used to output .css files
              when undefined defaults to `src`.
  `compress`  Whether the output .css files should be compressed
  `compile`   Custom compile function, accepting the arguments
              `(str, path)` returning the renderer.
  `firebug`   Emits debug infos in the generated css that can
              be used by the FireStylus Firebug plugin
  `linenos`   Emits comments in the generated css indicating
              the corresponding stylus line

Examples

Here we set up the custom compile function so that we may alter the renderer by providing additional settings.

By default, the compile function simply sets the filename and renders the CSS.

    function compile(str, path) {
      return stylus(str)
        .import(__dirname + '/css/mixins/blueprint')
        .import(__dirname + '/css/mixins/css3')
        .set('filename', path)
        .set('warn', true)
        .set('compress', true);
    }

Pass the middleware to Connect, grabbing .styl files from this directory and saving .css files to ./public. Also supplying our custom compile function.

Following that, we have a static layer setup to serve the .css files generated by Stylus.

    var stylus = require('stylus');

    var app = connect();

    app.use(stylus.middleware({
        src: __dirname
      , dest: __dirname + '/public'
      , compile: compile
    }));

    app.use(connect.static(__dirname + '/public'));

When force is used, the styles will unconditionally be re-compiled. But even without this option, the Stylus middleware is smart enough to detect changes in @imported files.

For development purposes, you can enable the firebug option if you want to use the FireStylus extension for Firebug and/or the linenos option to emit debug info in the generated CSS.

    function compile(str, path) {
      return stylus(str)
        .import(__dirname + '/css/mixins/blueprint')
        .import(__dirname + '/css/mixins/css3')
        .set('filename', path)
        .set('warn', true)
        .set('firebug', true)
        .set('linenos', true);
    }