npm install grunt-contrib-uglify --save-dev

grunt.loadNpmTasks('grunt-contrib-uglify');

Run this task with thegrunt uglify command.

Task targets, files and options may be specified according to the gruntConfiguring tasks guide.

This task primarily delegates toUglifyJS, so please consider their documentation as required reading for advanced configuration.

Type:BooleanObject
Default:{}

Turn on or off mangling with default options. If anObject is specified, it is passed directly toast.mangle_names()andast.compute_char_frequency() (mimicking command line behavior).View all options here.

Type:BooleanObject
Default:{}

Turn on or off source compression with default options. If anObject is specified, it is passed as options toUglifyJS.Compressor().View all options here.

Type:BooleanObject
Default:false

Turns on beautification of the generated source code.View all options here

Type:Boolean
Default:false

Parse a single expression, rather than a program (for parsing JSON)

Type:string
Choices:'min','gzip'
Default:'min'

Report minification result or both minification and gzip results.This is useful to see exactly how well uglify-js is performing but using'gzip' will make the task take 5-10x longer to complete.Example output.

Type:Boolean
Default:false

Iftrue, a source map file will be generated in the same directory as thedest file. By default it will have the same basename as thedest file, but with a.map extension.

Type:StringFunction
Default:undefined

To customize the name or location of the generated source map, pass a string to indicate where to write the source map to. If a function is provided, the uglify destination is passed as the argument and the return value will be used as the file name.

Type:StringFunction
Default:undefined

The location of an input source map from an earlier compilation, e.g. from CoffeeScript. If a function is provided, theuglify source is passed as the argument and the return value will be used as the sourceMap name. This only makes sensewhen there's one source file.

Type:Boolean
Default:false

Pass this flag if you want to include the content of source files in the source map as sourcesContent property.

Type:String
Default:undefined

With this option you can customize root URL that browser will use when looking for sources.

If the sources are not absolute URLs after prepending of thesourceMap.root, the sources are resolved relative to the source map.

Type:String
Default:undefined

Override the calculated value forsourceMappingURL in the source map. This is useful if the source map location is not relative to the base path of the minified file, i.e. when using a CDN

Type:String
Default:undefined

Wrap all of the code in a closure, an easy way to make sure nothing is leaking.For variables that need to be publicexports andglobal variables are made available.The value of wrap is the global variable exports will be available as.

Type:Boolean
Default:false

Enables to encode non-ASCII characters as \uXXXX.

Type:BooleanStringFunction
Default:undefined
Options:false'all''some'

Turn on preservation of comments.

• false will strip all comments
• 'all' will preserve all comments in code blocks that have not been squashed or dropped
• 'some' will preserve all comments that include a closure compiler style directive (@preserve@license@cc_on)
• Function specify your own comment preservation function. You will be passed the current node and the current comment and are expected to return eithertrue orfalse
• RegExp'/[RegExp]/' will preserve comments matching given RegExp or stringified RegExp

Type:String
Default:''

This string will be prepended to the minified output. Template strings (e.g.<%= config.value %>) will be expanded automatically.

Type:String
Default:''

This string will be appended to the minified output. Template strings (e.g.<%= config.value %>) will be expanded automatically.

Type:Boolean
Default:false

Set this totrue if you still care about full compliance with Internet Explorer 6-8 quirks.

Type:BooleanObject
Default:false

Turn on or off property mangling with default options. If anObject is specified, it is passed directly toast.mangle_properties() (mimicking command line behavior).View all options here.

Type:Boolean
Default:false

Use this flag in conjunction withmangle.properties to prevent built-in browser object properties from being mangled.

Type:Array
Default:[]

Use this withmangle.properties to pass one or more JSON files containing a list of variables and object propertiesthat should not be mangled. See theUglifyJS docs for more info on the file syntax.

Type:String
Default:''

A string that is a path to a JSON cache file that uglify will create and use to coordinate symbol mangling betweenmultiple runs of uglify. Note: this generated file uses the same JSON format as theexceptionsFiles files.

Type:Integer
Default:0

Preserve or enforce quotation mark style.

• 0 will use single or double quotes such as to minimize the number of bytes (prefers double quotes when both will do)
• 1 will always use single quotes
• 2 will always use double quotes
• 3 will preserve original quotation marks

This configuration will compress and mangle the input files using the default options.

// Project configuration.grunt.initConfig({uglify:{my_target:{files:{'dest/output.min.js':['src/input1.js','src/input2.js']}}}});

Specifymangle: false to prevent changes to your variable and function names.

// Project configuration.grunt.initConfig({uglify:{options:{mangle:false},my_target:{files:{'dest/output.min.js':['src/input.js']}}}});

You can specify identifiers to leave untouched with anreserved array in themangle options.

// Project configuration.grunt.initConfig({uglify:{options:{mangle:{reserved:['jQuery','Backbone']}},my_target:{files:{'dest/output.min.js':['src/input.js']}}}});

Generate a source map by setting thesourceMap option totrue. The generatedsource map will be in the same directory as the destination file. Its name will bethe basename of the destination file with a.map extension. Override thesedefaults with thesourceMapName attribute.

// Project configuration.grunt.initConfig({uglify:{my_target:{options:{sourceMap:true,sourceMapName:'path/to/sourcemap.map'},files:{'dest/output.min.js':['src/input.js']}}}});

Set thesourceMap.includeSources option totrue to embed your sources directly into the map. To includea source map from a previous compilation pass it as the value of thesourceMapIn option.

// Project configuration.grunt.initConfig({uglify:{my_target:{options:{sourceMap:{includeSources:true},sourceMapIn:'example/coffeescript-sourcemap.js',// input sourcemap from a previous compilation},files:{'dest/output.min.js':['src/input.js'],},},},});

Refer to theUglifyJS SourceMap Documentation for more information.

Specifydrop_console: true as part of thecompress options to discard calls toconsole.* functions.This will suppress warning messages in the console.

// Project configuration.grunt.initConfig({uglify:{options:{compress:{drop_console:true}},my_target:{files:{'dest/output.min.js':['src/input.js']}}}});

Specifybeautify: true to beautify your code for debugging/troubleshooting purposes.Pass an object to manually configure any other output options.

SeeUglifyJS documentation for more information.

// Project configuration.grunt.initConfig({uglify:{my_target:{options:{beautify:true},files:{'dest/output.min.js':['src/input.js']}},my_advanced_target:{options:{beautify:{width:80}},files:{'dest/output.min.js':['src/input.js']}}}});

In this example, runninggrunt uglify:my_target will prepend a banner created by interpolating thebanner template string with the config object. Here, those properties are the values imported from thepackage.json file (which are available via thepkg config property) plus today's date.

Note: you don't have to use an external JSON file. It's also valid to create thepkg object inline in the config. That being said, if you already have a JSON file, you might as well reference it.

// Project configuration.grunt.initConfig({pkg:grunt.file.readJSON('package.json'),uglify:{options:{banner:'/*! <%= pkg.name %> - v<%= pkg.version %> - '+'<%= grunt.template.today("yyyy-mm-dd") %> */'},my_target:{files:{'dest/output.min.js':['src/input.js']}}}});

You can also enable UglifyJS conditional compilation. This is commonly used to remove debug code blocks for production builds. This is equivalent to the command line--define option.

SeeUglifyJS global definitions documentation for more information.

// Project configuration.grunt.initConfig({uglify:{options:{compress:{global_defs:{'DEBUG':false},dead_code:true}},my_target:{files:{'dest/output.min.js':['src/input.js']}}}});

This configuration will compress and mangle the files dynamically.

// Project configuration.grunt.initConfig({uglify:{my_target:{files:[{expand:true,cwd:'src/js',src:'**/*.js',dest:'dest/js'}]}}});

This configuration will compress and mangle all js files separately in each folder.

Also exclude jQuery for mangling and ignore all*.min.js files.

// Project configuration.uglify:{dev:{options:{mangle:{reserved:['jQuery']}},files:[{expand:true,src:['dist/assets/js/*.js','!dist/assets/js/*.min.js'],dest:'dist/assets',cwd:'.',rename:function(dst,src){// To keep the source js files and make new files as `*.min.js`:// return dst + '/' + src.replace('.js', '.min.js');// Or to override to src:returnsrc;}}]}},

This configuration will turn on object property name mangling, but not mangle built-in browser object properties.Additionally, variables and object properties listed in themyExceptionsFile.json will be mangled. For more info,on the format of the exception file format please see theUglifyJS docs.

// Project configuration.grunt.initConfig({uglify:{options:{mangle:{properties:true},reserveDOMProperties:true,exceptionsFiles:['myExceptionsFile.json']},my_target:{files:{'dest/output.min.js':['src/input.js']}}}});

Turn on use of name mangling cache to coordinate mangled symbols between outputted uglify files. uglify will thegenerate a JSON cache file with the name provided in the options. Note: this generated file uses the same JSON formatas theexceptionsFiles files.

// Project configuration.grunt.initConfig({uglify:{options:{nameCache:'.tmp/grunt-uglify-cache.json',},my_target:{files:{'dest/output1.min.js':['src/input1.js'],'dest/output2.min.js':['src/input2.js']}}}});

• 2022-03-27   v5.1.0   Update dependencies. uglify-js ^3.15.2. Requires node 12+.
• 2020-07-16   v5.0.0   Requires node 10+. Update dependencies.
• 2019-03-21   v4.0.1   Update uglify-js to v3.5.0. Update dependencies.
• 2018-08-26   v4.0.0   Update dependencies. Requires Node.js >= 6.
• 2018-07-29   v3.4.0   Update uglify-js to v3.4.0.
• 2017-12-24   v3.3.0   Update uglify-js to v3.3.0.
• 2017-11-26   v3.2.1   Update uglify-js to v3.2.0.
• 2017-09-11   v3.1.0   Update uglify-js to v3.1.0.
• 2017-05-20   v3.0.1   Fix toplevel option.
• 2017-05-12   v3.0.0   Update uglify-js to v3.0.4.
• 2017-04-05   v2.3.0   Make CLI output less verbose.
• 2017-03-31   v2.2.1   Fix banner option.
• 2017-03-01   v2.2.0   Update uglify-js to v2.8.3.
• 2017-02-08   v2.1.0   Show size changes in output. Switch toobject.assign.
• 2016-07-19   v2.0.0   Update uglify-js to v2.7.0.screwIE8 is enabled by default.
• 2016-07-19   v1.0.2   Update grunt to ^1.0.0. Fixbeautify when passed as an object. Fix docs aboutreport values.
• 2016-03-16   v1.0.1   Downgrade maxmin for Node.js 0.10.
• 2016-03-04   v1.0.0   Use uglify-js ~2.6.2 to fix sourcemap issue. Improve docs forglobal-defs and--define options. AddsourceMapUrl option. Addbare_returns option. Optionally set report verbosity level using report option.
• 2016-01-29   v0.11.1   Update lodash to ^4.0.1. Update grunt-contrib-clean to ^0.7.0. Update grunt-contrib-jshint to ^0.12.0.
• 2015-11-20   v0.11.0   Update uglify-js to ~2.6.0.
• 2015-11-12   v0.10.1   Update uglify-js to ~2.5.
• 2015-10-27   v0.10.0   Update uglify-js to ^2.5.
• 2015-08-24   v0.9.2   Update uglify-js to ^2.4.24
• 2015-04-07   v0.9.1   More fixes formangle options.
• 2015-04-07   v0.9.0   Add hook into uglify-js's mangling functionality.
• 2015-03-30   v0.8.1   Lock uglify-js to 2.4.17 due to breaking changes.
• 2015-02-19   v0.8.0   AddscrewIE8 option. Fix issue with explicitcompress in Node.js 0.12.0.
• 2014-12-23   v0.7.0   AddsourceMapRoot options. Update readme descriptions. Remove reference to clean-css.
• 2014-09-17   v0.6.0   Output fixes. AddASCIIOnly option. Other fixes.
• 2014-07-25   v0.5.1   Update chalk to ^0.5.1. Output updates.
• 2014-03-01   v0.4.0   Remove grunt-lib-contrib dependency and add more colors.
• 2014-02-27   v0.3.3   Remove unnecessary calls togrunt.template.process.
• 2014-01-22   v0.3.2   Fix handling ofsourceMapIncludeSources option.
• 2014-01-20   v0.3.1   Fix relative path issue in sourcemaps.
• 2014-01-16   v0.3.0   Refactor sourcemap support.
• 2013-11-09   v0.2.7   Prepend banner ifsourceMap option not set, addresses #109.
• 2013-11-08   v0.2.6   Merge #45, #53, #85 (#105 by way of duping #53). Add support for banners in uglified files with sourcemaps. Update docs.
• 2013-10-28   v0.2.5   Add warning for banners when using sourcemaps.
• 2013-09-02   v0.2.4   Update sourcemap format via #83.
• 2013-06-10   v0.2.3   Addfooter option.
• 2013-05-31   v0.2.2   Revert #56 due to #58 untilchrome/239660firefox/870361 drop.
• 2013-05-22   v0.2.1   Update uglify-js to ~2.3.5 #55 #40. ChangesourcemappingUrl syntax #56. Disable sorting of names for consistent mangling #44. Update docs forsourceMapRoot #47 #25.
• 2013-03-14   v0.2.0   No longer report gzip results by default. Supportreport option.
• 2013-01-30   v0.1.2   Add better error reporting. Support for dynamic names of multiple sourcemaps.
• 2013-02-15   v0.1.1   First official release for Grunt 0.4.0.
• 2013-01-18   v0.1.1rc6   Update grunt/gruntplugin dependencies to rc6. Change in-development grunt/gruntplugin dependency versions from tilde version ranges to specific versions.
• 2013-01-09   v0.1.1rc5   Update to work with grunt v0.4.0rc5. Switch back tothis.files API.
• 2012-11-28   v0.1.0   Work in progress, not officially released yet.

Task submitted by"Cowboy" Ben Alman

This file was generated on Fri Apr 15 2022 21:00:08.