Minify files with UglifyJS.
This plugin requires Grunt ~0.4.0
If you haven't used Grunt before, be sure to check out the Getting Started guide, as it explains how to create a Gruntfile as well as install and use Grunt plugins. Once you're familiar with that process, you may install this plugin with this command:
npm install grunt-contrib-uglify --save-dev
Once the plugin has been installed, it may be enabled inside your Gruntfile with this line of JavaScript:
grunt.loadNpmTasks('grunt-contrib-uglify');
Run this task with the grunt uglify
command.
Task targets, files and options may be specified according to the grunt Configuring tasks guide.
This task primarily delegates to UglifyJS2, so please consider the UglifyJS documentation as required reading for advanced configuration.
Type: Boolean
Object
Default: {}
Turn on or off mangling with default options. If an Object
is specified, it is passed directly to ast.mangle_names()
and ast.compute_char_frequency()
(mimicking command line behavior).
Type: Boolean
Object
Default: {}
Turn on or off source compression with default options. If an Object
is specified, it is passed as options to UglifyJS.Compressor()
.
Type: Boolean
Object
Default: false
Turns on beautification of the generated source code. An Object
will be merged and passed with the options sent to UglifyJS.OutputStream()
Choices: false
'min'
'gzip'
Default: false
Either do not report anything, report only minification result, or report minification and gzip results. This is useful to see exactly how well Uglify is performing, but using 'gzip'
can add 5-10x runtime task execution.
Example ouput using 'gzip'
:
Original: 198444 bytes.
Minified: 101615 bytes.
Gzipped: 20084 bytes.
Type: Boolean
Default: false
If true
, a source map file will be generated in the same directory as the dest
file. By default it will have the same basename as the dest
file, but with a .map
extension.
Type: String
Function
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: String
Function
Default: undefined
The location of an input source map from an earlier compilation, e.g. from CoffeeScript. If a function is provided, the uglify source is passed as the argument and the return value will be used as the sourceMap name. This only makes sense when 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: Object
Default: undefined
Wrap all of the code in a closure with a configurable arguments/parameters list.
Each key-value pair in the enclose
object is effectively an argument-parameter pair.
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 public exports
and global
variables are made available.
The value of wrap is the global variable exports will be available as.
Type: Boolean
Default: false
When using wrap
this will make all global functions and variables available via the export variable.
Type: Boolean
String
Function
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 start with a bang (!
) or 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
Type: String
Default: empty string
This string will be prepended to the beginning of the minified output. It is processed using grunt.template.process, using the default options.
Type: String
Default: empty string
This string will be append to the end of the minified output. It is processed using grunt.template.process, using the default options.
(Default processing options are explained in the grunt.template.process documentation)
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']
}
}
}
});
Specify mangle: 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 an except
array in the mangle
options.
// Project configuration.
grunt.initConfig({
uglify: {
options: {
mangle: {
except: ['jQuery', 'Backbone']
}
},
my_target: {
files: {
'dest/output.min.js': ['src/input.js']
}
}
}
});
Configure basic source map output by specifying a file path for the sourceMap
option.
// Project configuration.
grunt.initConfig({
uglify: {
my_target: {
options: {
sourceMap: 'path/to/source-map.js'
},
files: {
'dest/output.min.js': ['src/input.js']
}
}
}
});
You can specify the parameters to pass to UglifyJS.SourceMap()
which will
allow you to configure advanced settings.
Refer to the UglifyJS SourceMap Documentation for more information.
// Project configuration.
grunt.initConfig({
uglify: {
my_target: {
options: {
sourceMap: 'path/to/source-map.js',
sourceMapRoot: 'http://example.com/path/to/src/', // the location to find your original source
sourceMapIn: 'example/coffeescript-sourcemap.js', // input sourcemap from a previous compilation
},
files: {
'dest/output.min.js': ['src/input.js'],
},
},
},
});
Specify drop_console: true
as part of the compress
options to discard calls to console.*
functions.
// Project configuration.
grunt.initConfig({
uglify: {
options: {
compress: {
drop_console: true
}
},
my_target: {
files: {
'dest/output.min.js': ['src/input.js']
}
}
}
});
Specify beautify: true
to beautify your code for debugging/troubleshooting purposes.
Pass an object to manually configure any other output options passed directly to UglifyJS.OutputStream()
.
See UglifyJS Codegen documentation for more information.
Note that manual configuration will require you to explicitly set beautify: true
if you want traditional, beautified output.
// 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,
beautify: true
}
},
files: {
'dest/output.min.js': ['src/input.js']
}
}
}
});
In this example, running grunt uglify:my_target
will prepend a banner created by interpolating the banner
template string with the config object. Here, those properties are the values imported from the package.json
file (which are available via the pkg
config property) plus today's date.
Note: you don't have to use an external JSON file. It's also valid to create the pkg
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.
See UglifyJS 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'
}]
}
}
});
- 2013-01-22 v0.3.2 fix handling of
sourceMapIncludeSources
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 prepending banner if sourceMap option not set, addresses
- 2013-11-08 v0.2.6 merged 45, 53, 85 (105 by way of duping 53) Added support for banners in uglified files with sourcemaps Updated docs
- 2013-10-28 v0.2.5 Added warning for banners when using sourcemaps
- 2013-09-02 v0.2.4 updated sourcemap format via /83
- 2013-06-10 v0.2.3 added footer option
- 2013-05-31 v0.2.2 Reverted /56 due to /58 until chrome/239660 firefox/870361 drop
- 2013-05-22 v0.2.1 Bumped uglify to ~2.3.5 /55 /40 Changed sourcemappingUrl syntax /56 Disabled sorting of names for consistent mangling /44 Updated docs for sourceMapRoot /47 /25
- 2013-03-14 v0.2.0 No longer report gzip results by default. Support
report
option. - 2013-01-30 v0.1.2 Added 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 Updating grunt/gruntplugin dependencies to rc6. Changing in-development grunt/gruntplugin dependency versions from tilde version ranges to specific versions.
- 2013-01-09 v0.1.1rc5 Updating to work with grunt v0.4.0rc5. Switching back to this.files api.
- 2012-11-28 v0.1.0 Work in progress, not yet officially released.
Task submitted by "Cowboy" Ben Alman
This file was generated on Thu Jan 23 2014 09:35:35.