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Package detail

uglifyjs-webpack-plugin

webpack-contrib2.4mMIT2.2.0TypeScript support: definitely-typed

UglifyJS plugin for webpack

uglify, uglify-js, uglify-es, webpack, webpack-plugin

readme

npm node deps tests cover chat size

UglifyJS Webpack Plugin

This plugin uses uglify-js to minify your JavaScript.

Requirements

This module requires a minimum of Node v6.9.0 and Webpack v4.0.0.

Getting Started

To begin, you'll need to install uglifyjs-webpack-plugin:

$ npm install uglifyjs-webpack-plugin --save-dev

Then add the plugin to your webpack config. For example:

webpack.config.js

const UglifyJsPlugin = require('uglifyjs-webpack-plugin');

module.exports = {
  optimization: {
    minimizer: [new UglifyJsPlugin()],
  },
};

And run webpack via your preferred method.

Options

test

Type: String|RegExp|Array<String|RegExp> Default: /\.js(\?.*)?$/i

Test to match files against.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        test: /\.js(\?.*)?$/i,
      }),
    ],
  },
};

include

Type: String|RegExp|Array<String|RegExp> Default: undefined

Files to include.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        include: /\/includes/,
      }),
    ],
  },
};

exclude

Type: String|RegExp|Array<String|RegExp> Default: undefined

Files to exclude.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        exclude: /\/excludes/,
      }),
    ],
  },
};

chunkFilter

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 UglifyJsPlugin({
        chunkFilter: (chunk) => {
          // Exclude uglification for the `vendor` chunk
          if (chunk.name === 'vendor') {
            return false;
          }

          return true;
        },
      }),
    ],
  },
};

cache

Type: Boolean|String Default: false

Enable file caching. Default path to cache directory: node_modules/.cache/uglifyjs-webpack-plugin.

ℹ️ If you use your own minify function please read the minify section for cache invalidation correctly.

Boolean

Enable/disable file caching.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        cache: true,
      }),
    ],
  },
};

String

Enable file caching and set path to cache directory.

webpack.config.js

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        cache: 'path/to/cache',
      }),
    ],
  },
};

cacheKeys

Type: Function<(defaultCacheKeys, file) -> Object> Default: defaultCacheKeys => defaultCacheKeys

Allows you to override default cache keys.

Default cache keys:

({
  'uglify-js': require('uglify-js/package.json').version, // uglify version
  'uglifyjs-webpack-plugin': require('../package.json').version, // plugin version
  'uglifyjs-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 UglifyJsPlugin({
        cache: true,
        cacheKeys: (defaultCacheKeys, file) => {
          defaultCacheKeys.myCacheKey = 'myCacheKeyValue';

          return defaultCacheKeys;
        },
      }),
    ],
  },
};

parallel

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.

Boolean

Enable/disable multi-process parallel running.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        parallel: true,
      }),
    ],
  },
};

Number

Enable multi-process parallel running and set number of concurrent runs.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        parallel: 4,
      }),
    ],
  },
};

sourceMap

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 UglifyJsPlugin({
        sourceMap: true,
      }),
    ],
  },
};

minify

Type: Function Default: undefined

Allows you to override default minify function. By default plugin uses uglify-js package. Useful for using and testing unpublished versions or forks.

⚠️ Always use require inside minify function when parallel option enabled.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        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 };
        },
      }),
    ],
  },
};

uglifyOptions

Type: Object Default: default

UglifyJS minify options.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        uglifyOptions: {
          warnings: false,
          parse: {},
          compress: {},
          mangle: true, // Note `mangle.properties` is `false` by default.
          output: null,
          toplevel: false,
          nameCache: null,
          ie8: false,
          keep_fnames: false,
        },
      }),
    ],
  },
};

extractComments

Type: Boolean|String|RegExp|Function<(node, comment) -> Boolean|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 uglifyOptions.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.

Boolean

Enable/disable extracting comments.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        extractComments: true,
      }),
    ],
  },
};

String

Extract all or some (use /^\**!|@preserve|@license|@cc_on/i RegExp) comments.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        extractComments: 'all',
      }),
    ],
  },
};

RegExp

All comments that match the given expression will be extracted to the separate file.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        extractComments: /@extract/i,
      }),
    ],
  },
};

Function<(node, comment) -> Boolean>

All comments that match the given expression will be extracted to the separate file.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        extractComments: function(astNode, comment) {
          if (/@extract/i.test(comment.value)) {
            return true;
          }

          return false;
        },
      }),
    ],
  },
};

Object

Allow to customize condition for extract comments, specify extracted file name and banner.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        extractComments: {
          condition: /^\**!|@preserve|@license|@cc_on/i,
          filename(file) {
            return `${file}.LICENSE`;
          },
          banner(licenseFile) {
            return `License information can be found in ${licenseFile}`;
          },
        },
      }),
    ],
  },
};
condition

Type: Boolean|String|RegExp|Function<(node, comment) -> Boolean|Object>

Condition what comments you need extract.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        extractComments: {
          condition: 'some',
          filename(file) {
            return `${file}.LICENSE`;
          },
          banner(licenseFile) {
            return `License information can be found in ${licenseFile}`;
          },
        },
      }),
    ],
  },
};
filename

Type: Regex|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 UglifyJsPlugin({
        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 UglifyJsPlugin({
        extractComments: {
          condition: true,
          filename(file) {
            return `${file}.LICENSE`;
          },
          banner(commentsFile) {
            return `My custom banner about license information ${commentsFile}`;
          },
        },
      }),
    ],
  },
};

warningsFilter

Type: Function<(warning, source) -> Boolean> Default: () => true

Allow to filter uglify-js warnings. Return true to keep the warning, false otherwise.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        warningsFilter: (warning, source) => {
          if (/Dropping unreachable code/i.test(warning)) {
            return true;
          }

          if (/filename\.js/i.test(source)) {
            return true;
          }

          return false;
        },
      }),
    ],
  },
};

Examples

Cache And Parallel

Enable cache and multi-process parallel running.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        cache: true,
        parallel: true,
      }),
    ],
  },
};

Preserve Comments

Extract all legal comments (i.e. /^\**!|@preserve|@license|@cc_on/i) and preserve /@license/i comments.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        uglifyOptions: {
          output: {
            comments: /@license/i,
          },
        },
        extractComments: true,
      }),
    ],
  },
};

Remove Comments

If you avoid building with comments, set uglifyOptions.output.comments to false as in this config:

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        uglifyOptions: {
          output: {
            comments: false,
          },
        },
      }),
    ],
  },
};

Custom Minify Function

Override default minify function - use terser for minification.

webpack.config.js

module.exports = {
  optimization: {
    minimizer: [
      new UglifyJsPlugin({
        // Uncomment lines below for cache invalidation correctly
        // cache: true,
        // cacheKeys(defaultCacheKeys) {
        //   delete defaultCacheKeys['uglify-js'];
        //
        //   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('terser').minify(file, uglifyJsOptions);
        },
      }),
    ],
  },
};

Contributing

Please take a moment to read our contributing guidelines if you haven't yet done so.

CONTRIBUTING

License

MIT

changelog

Changelog

All notable changes to this project will be documented in this file. See standard-version for commit guidelines.

2.2.0 (2019-07-31)

Features

2.1.3 (2019-05-15)

Bug Fixes

2.1.2 (2019-02-25)

Bug Fixes

  • invalidate cache after changing node version (#396) (380bb54)

2.1.1 (2018-12-27)

Bug Fixes

  • don't crash when no extracted comments (#387) (68ad71c)

2.1.0 (2018-12-22)

Bug Fixes

Features

  • chunkFilter option for filtering chunks (#382) (1e58c99)

2.0.1 (2018-09-18)

Bug Fixes

  • decrease minimum required uglify-js version (#357) (dc9d038)

2.0.0 (2018-09-14)

Bug Fixes

  • default extract comment condition is case insensitivity

Features

  • full coverage schema options validation
  • enable inline optimization by default

BREAKING CHANGES

  • Switch back to uglify-js (uglify-es is abandoned, if you need uglify ES6 code please use terser-webpack-plugin).
  • Changed function signature for warningsFilter option (now first argument is warning, second is source).
  • Enforces peerDependencies of "webpack": "^4.3.0.
  • Enforces engines of "node": ">= 6.9.0 <7.0.0 || >= 8.9.0

1.3.0 (2018-08-14)

Bug Fixes

  • all nodejs globals available inside minify function (#332) (24fe22b)
  • uglify/Runner: cpus length in a chroot environment (os.cpus()) (#341) (6d9c36f)

Features

1.2.7 (2018-06-25)

Bug Fixes

  • no warning when warningsFilter return false (#317) (cabee6c)

1.2.6 (2018-06-20)

Bug Fixes

  • disable inline optimization by default (#308) (6ab0918)
  • don't use a worker farm unless more than one process is required (#280) (3f0767b)
  • better handle invalid source map (#284) (dbebb3b)
  • perf regression with memory usage for source maps (#305) (3ca5eaf)
  • return missing important information for uglify warnings (#306) (4f50156)

1.2.5 (2018-04-18)

Bug Fixes

Performance Improvements

1.2.4 (2018-03-16)

Bug Fixes

  • index: correct default asset name {RegExp} (options.test) (#259) (f9e55fe)
  • index: don't remove legal comments by default (options.extractComments) (#250) (b31b574)

1.2.3 (2018-03-10)

Bug Fixes

  • index: correct [name].js.LICENSE file path (options.extractComments) (#249) (430111c)
  • index: relax default asset name {RegExp} (options.test) (#251) (d27e822)
  • package: update schema-utils v0.4.3...0.4.5 (dependencies) (#255) (4c0feb8)
  • package: updatecacache v10.0.1...10.0.4 (dependencies) (#253) (8b0c0cd)

Performance Improvements

  • index: switch to md4 for content hashing (#243) (14d2c4c)

1.2.2 (2018-02-24)

Bug Fixes

  • index: typo buildMobule => buildModule (#242) (259adad)
  • package: add webpack >= v4.0.0 (peerDependencies) (#239) (4c7f80a)

1.2.1 (2018-02-23)

Bug Fixes

  • index: tapable deprecation warnings (webpack >= v4.0.0) (#238) (23b1b38)

1.2.0 (2018-02-16)

Features

  • uglify: add missing toplevel, nameCache, keep_classnames, keep_fnames and safari10 options (uglifyOptions) (#229) (990de2a)

1.1.8 (2018-01-29)

Bug Fixes

  • package: use prepare instead of prepublish for release (43ffa48)

Reverts

  • README: mangle.props instead of mangle.properties (44b77e3)

1.1.7 (2018-01-29)

Bug Fixes

  • index: reduce memory consumption (cacheKey.hash) (#215) (2343274)

1.1.6 (2018-01-05)

Bug Fixes

  • index: don't pass compilation as an argument to UglifyJsPlugin.buildError (#201) (339ca10)

Reverts

  • package: use exact uglify-es version (dependencies) (#199) (#202) (426bafd)

1.1.5 (2017-12-27)

Bug Fixes

  • package: use exact uglify-es version (dependencies) (#199) (2e2ed36)

1.1.4 (2017-12-14)

Chores

1.1.3 (2017-12-14)

Refactoring

  • use serialize-javascript package instead own implementatin (#183) (8d7ebcd)

1.1.2 (2017-11-30)

Chores

1.1.1 (2017-11-23)

Bug Fixes

  • comments behavior (options.uglifyOptions.comments/options.extractComments) (#174) (321c9f6)
  • index: ensure to nullify inputSourceMap if sourcemap is unavailable (devtool) (#169) (062ec72)
  • index: set maxConcurrentCallsPerWorker to 1 (options.parallel) (#173) (07c57c1)

1.1.0 (2017-11-19)

Bug Fixes

  • index: exclude is ignored (options.exclude) (#164) (ad17690)
  • pass of {Boolean|Function} parameters being ignored (options.extractComments) (#168) (2c06f46)

Features

1.0.1 (2017-10-24)

Bug Fixes

  • minify: nameCache assignment (uglifyOptions.nameCache) (#147) (af11e8e)

1.0.0 (2017-10-23)

Features

  • update to uglify-es (#63) (1d62560)

  • add support for parallelization && caching (options.parallel) (#77) (ee16639)

  • index: add options validation (schema-utils) (#80) (f19b2de)

Bug Fixes

  • deps: cacache@10 with ISC licence (#145) (9331034)
  • typo "filterd" -> "filtered" (#37) (238c373)
  • package: mv uglify2 to dependencies && update peerDependencies (#45) (93b0cd2)
  • uglify: use Compress API not ast.transform (990f2e2)

Code Refactoring

BREAKING CHANGES

  • Enforces peerDependencies of "webpack": ">= 3.0.0-rc.0 || ^3.0.0".
  • Enforces engines of "node": ">=4.3.0 < 5.0.0 || >= 5.10

1.0.0-rc.0 (2017-10-23)

1.0.0-beta.3 (2017-09-29)

1.0.0-beta.2 (2017-07-21)

Features

  • add support for parallelization && caching (options.parallel) (#77) (ee16639)
  • index: add options validation (schema-utils) (#80) (f19b2de)

1.0.0-beta.1 (2017-07-06)

Features

1.0.0-beta.0 (2017-06-29)

Bug Fixes

  • typo "filterd" -> "filtered" (#37) (238c373)
  • package: mv uglify2 to dependencies && update peerDependencies (#45) (93b0cd2)
  • uglify: use Compress API not ast.transform (990f2e2)

Code Refactoring

BREAKING CHANGES

  • Enforces peerDependencies of "webpack": ">= 3.0.0-rc.0 || ^3.0.0".
  • Enforces engines of "node": ">=4.3.0 < 5.0.0 || >= 5.10

0.4.6 (2017-06-29)

Bug Fixes

  • typo "filterd" -> "filtered" (#37) (238c373)
  • package: mv uglify2 to dependencies && update peerDependencies (#45) (93b0cd2)
  • uglify: use Compress API not ast.transform (990f2e2)