js-to-sass-var-loader

This project is not maintained any more. Please try the js-to-styles-var-loader, which is a more flexible loader, it handles Less, too.

js-to-sass-var-loader

A Webpack loader to share data for sass variables between javascript modules and sass files

This loader is for that special case when you would like to import data from a javascript module into a sass file. The sass loader complains, because importing js module is not a valid sass instruction.

The loader only handles the case when you want to inject sass variables into a sass file via a javascript module.

Prerequisites

• Nodejs >= 4.0
• sass for css pre-processing
• Webpack for module bundle

Setting up Webpack config

Probably you use sass-loader with Webpack. The usage in this case is pretty simple: just put this loader before sass-loader in your webpack config:

{
  rules: [
    test: /\.sass$/,
    use: [
      {
        loader: "style-loader"
      },
      {
        loader: "css-loader"
      },
      {
        loader: "sass-loader"
      },
      {
        loader: "js-to-sass-var-loader"
      }
    ]
  ]
}

Usage

Let's assume we would like to store some variable data in a module like this:

// colors.js
 
const colors = {
  'fancy-white': '#FFFFFE',
  'fancy-black': '#000001'
};
 
module.exports = colors;

You can use this module in your favorite templates / frameworks etc., and you don't want to repeat yourself when using these colors in a sass file as variable (e.g. $fancy-white: #FFFFFE; /*...*/ background-color: $fancy-white). In this situation just require your module in the beginning of your sass module:

require('relative/path/to/colors.js');
 
// ...
.some-class {
  background-color: $fancy-white
}
// ...

The form of the required data is important: it must be an object with key/values pair, the key will be the name of the sass variable.

Misc

You can use other require form (require('relative/path/to/module').someProperty), too.

Demo

You can try the loader via a small fake app in the demo folder:

cd demo
npm i
npm run demo

The webpack dev server serves the app on localhost:8030. In the app we share data between js and sass modules.

Development

Run tests with npm test or npm run test:watch.

The transformer is developed with tdd, so if you would like to contribute, please, write your tests for your new functionality, and send pull request to integrate your changes.