Fewer style tags (older IE has a limit)
Additional HTTP request
Extract text from a bundle, or bundles, into a separate file.
npm install --save-dev extract-text-webpack-plugin
# for webpack 2
npm install --save-dev extract-text-webpack-plugin@2.1.2
# for webpack 1
npm install --save-dev extract-text-webpack-plugin@1.0.1
:warning: Since webpack v4 the
extract-text-webpack-pluginshould not be used for css. Use mini-css-extract-plugin instead.:warning: For webpack v1, see the README in the webpack-1 branch.
const ExtractTextPlugin = require("extract-text-webpack-plugin");
module.exports = {
module: {
rules: [
{
test: /\.css$/,
use: ExtractTextPlugin.extract({
fallback: "style-loader",
use: "css-loader"
})
}
]
},
plugins: [
new ExtractTextPlugin("styles.css"),
]
}
It moves all the required *.css modules in entry chunks into a separate CSS file. So your styles are no longer inlined into the JS bundle, but in a separate CSS file (styles.css). If your total stylesheet volume is big, it will be faster because the CSS bundle is loaded in parallel to the JS bundle.
| Advantages | Caveats |
|---|---|
Advantages Caveats Fewer style tags (older IE has a limit) Additional HTTP request |
Additional HTTP request |
Advantages Caveats CSS SourceMap (with Longer compilation time |
Longer compilation time |
Advantages Caveats CSS requested in parallel No runtime public path modification |
No runtime public path modification |
Advantages Caveats CSS cached separate No Hot Module Replacement |
No Hot Module Replacement |
Advantages Caveats Faster runtime (less code and DOM operations) ... |
... |
new ExtractTextPlugin(options: filename | object)
| Name | Type | Description |
|---|---|---|
Name Type Description
|
{String} |
Unique ident for this plugin instance. (For advanced usage only, by default automatically generated) |
Name Type Description
|
{String\|Function} |
Name of the result file. May contain
[name]
,
[id]
and
[contenthash] |
Name Type Description
|
{Boolean} |
Extract from all additional chunks too (by default it extracts only from the initial chunk(s))
When using CommonsChunkPlugin
and there are extracted chunks (from
ExtractTextPlugin.extract
) in the commons chunk,
allChunks
must
be set to
true |
Name Type Description
|
{Boolean} |
Disables the plugin |
Name Type Description
|
{Boolean} |
Disables order check (useful for CSS Modules!),
false
by default |
[name] name of the chunk[id] number of the chunk[contenthash] hash of the content of the extracted file[<hashType>:contenthash:<digestType>:<length>] optionally you can configure
hashTypes, e.g. sha1, md5, sha256, sha512digestTypes, e.g. hex, base26, base32, base36, base49, base52, base58, base62, base64length, the length of the hash in chars:warning:
ExtractTextPlugingenerates a file per entry, so you must use[name],[id]or[contenthash]when using multiple entries.
#extractExtractTextPlugin.extract(options: loader | object)
Creates an extracting loader from an existing loader. Supports loaders of type { loader: [name]-loader -> {String}, options: {} -> {Object} }.
| Name | Type | Description |
|---|---|---|
Name Type Description
|
{String}
/
{Array}
/
{Object} |
Loader(s) that should be used for converting the resource to a CSS exporting module (required) |
Name Type Description
|
{String}
/
{Array}
/
{Object} |
loader(e.g
'style-loader'
) that should be used when the CSS is not extracted (i.e. in an additional chunk when
allChunks: false
) |
Name Type Description
|
{String} |
Override the
publicPath
setting for this loader |
There is also an extract function on the instance. You should use this if you have more than one instance of ExtractTextPlugin.
const ExtractTextPlugin = require('extract-text-webpack-plugin');
// Create multiple instances
const extractCSS = new ExtractTextPlugin('stylesheets/[name]-one.css');
const extractLESS = new ExtractTextPlugin('stylesheets/[name]-two.css');
module.exports = {
module: {
rules: [
{
test: /\.css$/,
use: extractCSS.extract([ 'css-loader', 'postcss-loader' ])
},
{
test: /\.less$/i,
use: extractLESS.extract([ 'css-loader', 'less-loader' ])
},
]
},
plugins: [
extractCSS,
extractLESS
]
};
The configuration is the same, switch out sass-loader for less-loader when necessary.
const ExtractTextPlugin = require('extract-text-webpack-plugin');
module.exports = {
module: {
rules: [
{
test: /\.scss$/,
use: ExtractTextPlugin.extract({
fallback: 'style-loader',
use: ['css-loader', 'sass-loader']
})
}
]
},
plugins: [
new ExtractTextPlugin('style.css')
//if you want to pass in options, you can do so:
//new ExtractTextPlugin({
// filename: 'style.css'
//})
]
}
url() ResolvingIf you are finding that urls are not resolving properly when you run webpack. You can expand your loader functionality with options. The url: false property allows your paths resolved without any changes.
const ExtractTextPlugin = require('extract-text-webpack-plugin');
module.exports = {
module: {
rules: [
{
test: /\.scss$/,
use: ExtractTextPlugin.extract({
fallback: 'style-loader',
use: [
{
loader: 'css-loader',
options: {
// If you are having trouble with urls not resolving add this setting.
// See https://github.com/webpack-contrib/css-loader#url
url: false,
minimize: true,
sourceMap: true
}
},
{
loader: 'sass-loader',
options: {
sourceMap: true
}
}
]
})
}
]
}
}
filename parameter could be Function. It passes getPath to process the format like css/[name].css and returns the real file name, css/js/a.css. You can replace css/js with css then you will get the new path css/a.css.
entry: {
'js/a': "./a"
},
plugins: [
new ExtractTextPlugin({
filename: (getPath) => {
return getPath('css/[name].css').replace('css/js', 'css');
},
allChunks: true
})
]
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