ember-cli-css-preprocess

ember-cli-css-preprocess

Preprocess your stylesheets with multiple preprocessors.

Currently supported preprocessors:

• postcss
• node-sass
• less

Please feel free to fork in order to add more processors!

You can determine in which order the stylesheets are processed!

Installation

ember install ember-cli-css-preprocess

Usage

Basic configuration

All the configuration for this plugin is stored in the ember-cli-build.js in the root-directory of your ember application.

Search for the following lines:

    var app = new EmberApp(defaults, {
        // Add options here
    ...

And add the the basic options:

    var app = new EmberApp(defaults, {
        // Add options here
        styleProcessorOptions: {
            processors: [],
            extension:     'css'
        }
    ...

Adding a preprocessor

Currently there a two available preprocessors which you can chain in any order (even multiple times if you want).

Available processors:

• sass
• postcss
• less

To add on simply pass in an object to the processors-Array containing a type-Property with the processor title.

Adding a Sass Preprocessor:

    var app = new EmberApp(defaults, {
        // Add options here
        styleProcessorOptions: {
            processors: [{
                type: 'sass'
            }],
            extension: 'scss'
        }
    ...

By changing the extension-property you can specify the extension of your stylesheets. Because we are only processing our sheets with Sass we set the extension to scss.

Annotation: You can also pass all setting you could pass to node-sass by setting the options-object in the processor object. By default the only setting is the includePath which is set to your styles-folder. This allows you to include any stylesheet in your folder with the @import-rule

Adding a PostCSS Preprocessor:

    var app = new EmberApp(defaults, {
        // Add options here
        styleProcessorOptions: {
            processors: [{
                type: 'postcss',
                plugins: [{
                    module: require('autoprefixer'),
                    options: {
                        browsers: [
                            'last 2 versions'
                        ]
                    }
                ]
            }],
            extension: 'css'
        }
    ...

This is a basic postcss implementation using the autoprefixer plugin.

The plugin-array is filled with objects with the module and the options properties. The latter obviously contains the options which are passed into the module/plugin when processing your stylesheets.

Annotation: Before requiring any postcss-plugin you have to install it via npm (e.g. npm install autoprefixer --save).

You can also add a custom parser or syntax by adding it to the processor object. Here is an example which uses the postcss-scss parser (for adding a syntax, use the syntax property):

    var app = new EmberApp(defaults, {
        // Add options here
        styleProcessorOptions: {
            processors: [{
                type: 'postcss',
                parser: require('postcss-scss'),
                //syntax: require('postcss-scss'),
                plugins: [{
                    module: require('autoprefixer'),
                    options: {
                        browsers: [
                            'last 2 versions'
                        ]
                    }
                ]
            }],
            extension: 'css'
        }
    ...

Adding a less Preprocessor:

    var app = new EmberApp(defaults, {
        // Add options here
        styleProcessorOptions: {
            processors: [{
                type: 'less'
            }],
            extension: 'css'
        }
    ...

To include any less plugin you can make use of the plugins-array, it is handled like the postcss-plugin array.

Using multiple processors:

    var app = new EmberApp(defaults, {
        // Add options here
        styleProcessorOptions: {
            processors: [{
                type: 'postcss',
                plugins: [{
                    module: require('autoprefixer'),
                    options: {
                        browsers: [
                            'last 2 versions'
                        ]
                    }
                ]
            }, {
                type: 'sass'
            }
            ],
            extension: 'css'
        }
    ...

This example should clarify how to chain preprocessors. The position inside the processors-array determines the order in which the stylesheets are processed by each preprocessors (from top to bottom).

Setup processor to parse specific files only:

    var app = new EmberApp(defaults, {
        // Add options here
        styleProcessorOptions: {
            processors: [{
                type: 'postcss',
                file: ['test.css'],
                plugins: [{
                    module: require('autoprefixer'),
                    options: {
                        browsers: [
                            'last 2 versions'
                        ]
                    }
                ]
            }, {
                type: 'sass'
            }
            ],
            extension: 'css'
        }
    ...

With this setup the postcss processor will only process the file test.css. The file property can either be a string or an array of strings.