dxm-mini-css-extract-plugin
v0.0.1
Published
extracts CSS into separate files
Downloads
4
Readme
This plugin extracts CSS into separate files. It creates a CSS file per JS file which contains CSS. It supports On-Demand-Loading of CSS and SourceMaps.
It builds on top of a new webpack v4 feature (module types) and requires webpack 4 to work.
Compared to the extract-text-webpack-plugin:
- Async loading
- No duplicate compilation (performance)
- Easier to use
- Specific to CSS
TODO:
- HMR support
npm install --save-dev mini-css-extract-plugin
Configuration
Minimal example
webpack.config.js
const MiniCssExtractPlugin = require("mini-css-extract-plugin");
module.exports = {
plugins: [
new MiniCssExtractPlugin({
// Options similar to the same options in webpackOptions.output
// both options are optional
filename: "[name].css",
chunkFilename: "[id].css"
})
],
module: {
rules: [
{
test: /\.css$/,
use: [
{
loader: MiniCssExtractPlugin.loader,
options: {
// you can specify a publicPath here
// by default it use publicPath in webpackOptions.output
publicPath: '../'
}
},
"css-loader"
]
}
]
}
}
Advanced configuration example
This plugin should be used only on production
builds without style-loader
in the loaders chain, especially if you want to have HMR in development
.
Here is an example to have both HMR in development
and your styles extracted in a file for production
builds.
(Loaders options left out for clarity, adapt accordingly to your needs.)
webpack.config.js
const MiniCssExtractPlugin = require("mini-css-extract-plugin");
const devMode = process.env.NODE_ENV !== 'production'
module.exports = {
plugins: [
new MiniCssExtractPlugin({
// Options similar to the same options in webpackOptions.output
// both options are optional
filename: devMode ? '[name].css' : '[name].[hash].css',
chunkFilename: devMode ? '[id].css' : '[id].[hash].css',
})
],
module: {
rules: [
{
test: /\.(sa|sc|c)ss$/,
use: [
devMode ? 'style-loader' : MiniCssExtractPlugin.loader,
'css-loader',
'postcss-loader',
'sass-loader',
],
}
]
}
}
Minimizing For Production
While webpack 5 is likely to come with a CSS minimizer built-in, with webpack 4 you need to bring your own. To minify the output, use a plugin like optimize-css-assets-webpack-plugin. Setting optimization.minimizer
overrides the defaults provided by webpack, so make sure to also specify a JS minimizer:
webpack.config.js
const UglifyJsPlugin = require("uglifyjs-webpack-plugin");
const MiniCssExtractPlugin = require("mini-css-extract-plugin");
const OptimizeCSSAssetsPlugin = require("optimize-css-assets-webpack-plugin");
module.exports = {
optimization: {
minimizer: [
new UglifyJsPlugin({
cache: true,
parallel: true,
sourceMap: true // set to true if you want JS source maps
}),
new OptimizeCSSAssetsPlugin({})
]
},
plugins: [
new MiniCssExtractPlugin({
filename: "[name].css",
chunkFilename: "[id].css"
})
],
module: {
rules: [
{
test: /\.css$/,
use: [
MiniCssExtractPlugin.loader,
"css-loader"
]
}
]
}
}
Features
Using preloaded or inlined CSS
The runtime code detects already added CSS via <link>
or <style>
tag.
This can be useful when injecting CSS on server-side for Server-Side-Rendering.
The href
of the <link>
tag has to match the URL that will be used for loading the CSS chunk.
The data-href
attribute can be used for <link>
and <style>
too.
When inlining CSS data-href
must be used.
Extracting all CSS in a single file
Similar to what extract-text-webpack-plugin does, the CSS
can be extracted in one CSS file using optimization.splitChunks.cacheGroups
.
webpack.config.js
const MiniCssExtractPlugin = require("mini-css-extract-plugin");
module.exports = {
optimization: {
splitChunks: {
cacheGroups: {
styles: {
name: 'styles',
test: /\.css$/,
chunks: 'all',
enforce: true
}
}
}
},
plugins: [
new MiniCssExtractPlugin({
filename: "[name].css",
})
],
module: {
rules: [
{
test: /\.css$/,
use: [
MiniCssExtractPlugin.loader,
"css-loader"
]
}
]
}
}
Extracting CSS based on entry
You may also extract the CSS based on the webpack entry name. This is especially useful if you import routes dynamically but want to keep your CSS bundled according to entry. This also prevents the CSS duplication issue one had with the ExtractTextPlugin.
const path = require('path');
const MiniCssExtractPlugin = require("mini-css-extract-plugin");
function recursiveIssuer(m) {
if (m.issuer) {
return recursiveIssuer(m.issuer);
} else if (m.name) {
return m.name;
} else {
return false;
}
}
module.exports = {
entry: {
foo: path.resolve(__dirname, 'src/foo'),
bar: path.resolve(__dirname, 'src/bar')
},
optimization: {
splitChunks: {
cacheGroups: {
fooStyles: {
name: 'foo',
test: (m,c,entry = 'foo') => m.constructor.name === 'CssModule' && recursiveIssuer(m) === entry,
chunks: 'all',
enforce: true
},
barStyles: {
name: 'bar',
test: (m,c,entry = 'bar') => m.constructor.name === 'CssModule' && recursiveIssuer(m) === entry,
chunks: 'all',
enforce: true
}
}
}
},
plugins: [
new MiniCssExtractPlugin({
filename: "[name].css",
})
],
module: {
rules: [
{
test: /\.css$/,
use: [
MiniCssExtractPlugin.loader,
"css-loader"
]
}
]
}
}
Long Term Caching
For long term caching use filename: "[contenthash].css"
. Optionally add [name]
.
Media Query Plugin
If you'd like to extract the media queries from the extracted CSS (so mobile users don't need to load desktop specific CSS anymore) you should use the media-query-plugin. It will take over the filename option of the mini-css-extract-plugin and recognize its generated CSS chunks.