This plugin uses terser to minify your JavaScript.
This module requires a minimum of Node v6.9.0 and Webpack v4.0.0.
To begin, you'll need to install terser-webpack-plugin
:
$ npm install terser-webpack-plugin --save-dev
Then add the plugin to your webpack
config. For example:
webpack.config.js
const TerserPlugin = require('terser-webpack-plugin');
module.exports = {
optimization: {
minimizer: [new TerserPlugin()],
},
};
And run webpack
via your preferred method.
Type: String|RegExp|Array<String|RegExp>
Default: /\.m?js(\?.*)?$/i
Test to match files against.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
test: /\.js(\?.*)?$/i,
}),
],
},
};
Type: String|RegExp|Array<String|RegExp>
Default: undefined
Files to include.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
include: /\/includes/,
}),
],
},
};
Type: String|RegExp|Array<String|RegExp>
Default: undefined
Files to exclude.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
exclude: /\/excludes/,
}),
],
},
};
Type: Function<(chunk) -> boolean>
Default: () => true
Allowing to filter which chunks should be uglified (by default all chunks are uglified).
Return true
to uglify the chunk, false
otherwise.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
chunkFilter: (chunk) => {
// Exclude uglification for the `vendor` chunk
if (chunk.name === 'vendor') {
return false;
}
return true;
},
}),
],
},
};
Type: Boolean|String
Default: false
Enable file caching.
Default path to cache directory: node_modules/.cache/terser-webpack-plugin
.
ℹ️ If you use your own
minify
function please read theminify
section for cache invalidation correctly.
Enable/disable file caching.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
cache: true,
}),
],
},
};
Enable file caching and set path to cache directory.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
cache: 'path/to/cache',
}),
],
},
};
Type: Function<(defaultCacheKeys, file) -> Object>
Default: defaultCacheKeys => defaultCacheKeys
Allows you to override default cache keys.
Default cache keys:
({
terser: require('terser/package.json').version, // terser version
'terser-webpack-plugin': require('../package.json').version, // plugin version
'terser-webpack-plugin-options': this.options, // plugin options
path: compiler.outputPath ? `${compiler.outputPath}/${file}` : file, // asset path
hash: crypto
.createHash('md4')
.update(input)
.digest('hex'), // source file hash
});
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
cache: true,
cacheKeys: (defaultCacheKeys, file) => {
defaultCacheKeys.myCacheKey = 'myCacheKeyValue';
return defaultCacheKeys;
},
}),
],
},
};
Type: Boolean|Number
Default: false
Use multi-process parallel running to improve the build speed.
Default number of concurrent runs: os.cpus().length - 1
.
ℹ️ Parallelization can speedup your build significantly and is therefore highly recommended.
Enable/disable multi-process parallel running.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
parallel: true,
}),
],
},
};
Enable multi-process parallel running and set number of concurrent runs.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
parallel: 4,
}),
],
},
};
Type: Boolean
Default: false
Use source maps to map error message locations to modules (this slows down the compilation).
If you use your own minify
function please read the minify
section for handling source maps correctly.
⚠️ cheap-source-map
options don't work with this plugin.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
sourceMap: true,
}),
],
},
};
Type: Function
Default: undefined
Allows you to override default minify function. By default plugin uses terser package. Useful for using and testing unpublished versions or forks.
⚠️ Always userequire
insideminify
function whenparallel
option enabled.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
minify: (file, sourceMap) => {
const extractedComments = [];
// Custom logic for extract comments
const { error, map, code, warnings } = require('uglify-module') // Or require('./path/to/uglify-module')
.minify(file, {
/* Your options for minification */
});
return { error, map, code, warnings, extractedComments };
},
}),
],
},
};
Type: Object
Default: default
Terser minify options.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
terserOptions: {
ecma: undefined,
warnings: false,
parse: {},
compress: {},
mangle: true, // Note `mangle.properties` is `false` by default.
module: false,
output: null,
toplevel: false,
nameCache: null,
ie8: false,
keep_classnames: undefined,
keep_fnames: false,
safari10: false,
},
}),
],
},
};
Type: Boolean|String|RegExp|Function<(node, comment) -> Boolean|Object>|Object
Default: false
Whether comments shall be extracted to a separate file, (see details).
By default extract only comments using /^\**!|@preserve|@license|@cc_on/i
regexp condition and remove remaining comments.
If the original file is named foo.js
, then the comments will be stored to foo.js.LICENSE
.
The terserOptions.output.comments
option specifies whether the comment will be preserved, i.e. it is possible to preserve some comments (e.g. annotations) while extracting others or even preserving comments that have been extracted.
Enable/disable extracting comments.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
extractComments: true,
}),
],
},
};
Extract all
or some
(use /^\**!|@preserve|@license|@cc_on/i
RegExp) comments.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
extractComments: 'all',
}),
],
},
};
All comments that match the given expression will be extracted to the separate file.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
extractComments: /@extract/i,
}),
],
},
};
All comments that match the given expression will be extracted to the separate file.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
extractComments: (astNode, comment) => {
if (/@extract/i.test(comment.value)) {
return true;
}
return false;
},
}),
],
},
};
Allow to customize condition for extract comments, specify extracted file name and banner.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
extractComments: {
condition: /^\**!|@preserve|@license|@cc_on/i,
filename: (file) => {
return `${file}.LICENSE`;
},
banner: (licenseFile) => {
return `License information can be found in ${licenseFile}`;
},
},
}),
],
},
};
Type: Boolean|String|RegExp|Function<(node, comment) -> Boolean|Object>
Condition what comments you need extract.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
extractComments: {
condition: 'some',
filename: (file) => {
return `${file}.LICENSE`;
},
banner: (licenseFile) => {
return `License information can be found in ${licenseFile}`;
},
},
}),
],
},
};
Type: String|Function<(string) -> String>
Default: ${file}.LICENSE
The file where the extracted comments will be stored.
Default is to append the suffix .LICENSE
to the original filename.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
extractComments: {
condition: /^\**!|@preserve|@license|@cc_on/i,
filename: 'extracted-comments.js',
banner: (licenseFile) => {
return `License information can be found in ${licenseFile}`;
},
},
}),
],
},
};
Type: Boolean|String|Function<(string) -> String>
Default: /*! For license information please see ${commentsFile} */
The banner text that points to the extracted file and will be added on top of the original file.
Can be false
(no banner), a String
, or a Function<(string) -> String>
that will be called with the filename where extracted comments have been stored.
Will be wrapped into comment.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
extractComments: {
condition: true,
filename: (file) => {
return `${file}.LICENSE`;
},
banner: (commentsFile) => {
return `My custom banner about license information ${commentsFile}`;
},
},
}),
],
},
};
Type: Function<(warning, source) -> Boolean>
Default: () => true
Allow to filter terser warnings.
Return true
to keep the warning, false
otherwise.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
warningsFilter: (warning, source) => {
if (/Dropping unreachable code/i.test(warning)) {
return true;
}
if (/filename\.js/i.test(source)) {
return true;
}
return false;
},
}),
],
},
};
Enable cache and multi-process parallel running.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
cache: true,
parallel: true,
}),
],
},
};
Extract all legal comments (i.e. /^\**!|@preserve|@license|@cc_on/i
) and preserve /@license/i
comments.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
terserOptions: {
output: {
comments: /@license/i,
},
},
extractComments: true,
}),
],
},
};
If you avoid building with comments, set terserOptions.output.comments to false as in this config:
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
terserOptions: {
output: {
comments: false,
},
},
}),
],
},
};
Override default minify function - use uglify-js
for minification.
webpack.config.js
module.exports = {
optimization: {
minimizer: [
new TerserPlugin({
// Uncomment lines below for cache invalidation correctly
// cache: true,
// cacheKeys: (defaultCacheKeys) => {
// delete defaultCacheKeys.terser;
//
// return Object.assign(
// {},
// defaultCacheKeys,
// { 'uglify-js': require('uglify-js/package.json').version },
// );
// },
minify: (file, sourceMap) => {
// https://github.com/mishoo/UglifyJS2#minify-options
const uglifyJsOptions = {
/* your `uglify-js` package options */
};
if (sourceMap) {
uglifyJsOptions.sourceMap = {
content: sourceMap,
};
}
return require('uglify-js').minify(file, uglifyJsOptions);
},
}),
],
},
};
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