Extract css class names from required css module files, so we can render it on server.
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README.md

babel-plugin-css-modules-transform Circle CI

🎉 Babel 6 and Babel 7 compatible

⚠️ Babel 7 compatibility added in 1.4.0

This Babel plugin finds all requires for css module files and replace them with a hash where keys are class names and values are generated css class names.

This plugin is based on the fantastic css-modules-require-hook.

Warning

This plugin is experimental, pull requests are welcome.

Do not run this plugin as part of webpack frontend configuration. This plugin is intended only for backend compilation.

Example

/* test.css */

.someClass {
    color: red;
}
// component.js
const styles = require('./test.css');

console.log(styles.someClass);

// transformed file
const styles = {
    'someClass': 'Test__someClass___2Frqu'
}

console.log(styles.someClass); // prints Test__someClass___2Frqu

Installation

npm install --save-dev babel-plugin-css-modules-transform

Include plugin in .babelrc

{
    "plugins": ["css-modules-transform"]
}

With custom options css-modules-require-hook options

{
    "plugins": [
        [
            "css-modules-transform", {
                "append": [
                    "npm-module-name",
                    "./path/to/module-exporting-a-function.js"
                ],
                "camelCase": false,
                "createImportedName": "npm-module-name",
                "createImportedName": "./path/to/module-exporting-a-function.js",
                "devMode": false,
                "extensions": [".css", ".scss", ".less"], // list extensions to process; defaults to .css
                "generateScopedName": "[name]__[local]___[hash:base64:5]", // in case you don't want to use a function
                "generateScopedName": "./path/to/module-exporting-a-function.js", // in case you want to use a function
                "generateScopedName": "npm-module-name",
                "hashPrefix": "string",
                "ignore": "*css",
                "ignore": "./path/to/module-exporting-a-function-or-regexp.js",
                "preprocessCss": "./path/to/module-exporting-a-function.js",
                "preprocessCss": "npm-module-name",
                "processCss": "./path/to/module-exporting-a-function.js",
                "processCss": "npm-module-name",
                "processorOpts": "npm-module-name",
                "processorOpts": "./path/to/module/exporting-a-plain-object.js",
                "mode": "string",
                "prepend": [
                    "npm-module-name",
                    "./path/to/module-exporting-a-function.js"
                ],
                "extractCss": "./dist/stylesheets/combined.css"
            }
        ]
    ]
}

Using a preprocessor

When using this plugin with a preprocessor, you'll need to configure it as such:

// ./path/to/module-exporting-a-function.js
var sass = require('node-sass');
var path = require('path');

module.exports = function processSass(data, filename) {
    var result;
    result = sass.renderSync({
        data: data,
        file: filename
    }).css;
    return result.toString('utf8');
};

and then add any relevant extensions to your plugin config:

{
    "plugins": [
        [
            "css-modules-transform", {
                "preprocessCss": "./path/to/module-exporting-a-function.js",
                "extensions": [".css", ".scss"]
            }
        ]
    ]
}

Extract CSS Files

When you publish a library, you might want to ship compiled css files as well to help integration in other projects.

An more complete alternative is to use babel-plugin-webpack-loaders but be aware that a new webpack instance is run for each css file, this has a huge overhead. If you do not use fancy stuff, you might consider using babel-plugin-css-modules-transform instead.

To combine all css files in a single file, give its name:

{
    "plugins": [
        [
            "css-modules-transform", {
                "extractCss": "./dist/stylesheets/combined.css"
            }
        ]
    ]
}

To extract all files in a single directory, give an object:

{
    "plugins": [
        [
            "css-modules-transform", {
                "extractCss": {
                    "dir": "./dist/stylesheets/",
                    "relativeRoot": "./src/",
                    "filename": "[path]/[name].css"
                }
            }
        ]
    ]
}

Note that relativeRoot is used to resolve relative directory names, available as [path] in filename pattern.

Keeping import

To keep import statements you should set option keepImport to true. In this way, simultaneously with the converted values, the import will be described as unassigned call expression.

// before
const styles = require('./test.css');
// after
require('./test.css');

const styles = {
    'someClass': 'Test__someClass___2Frqu'
}

Alternatives

License

MIT