What is gulp-uglify?
The gulp-uglify package is a Gulp plugin that minifies JavaScript files using UglifyJS. It helps in reducing the file size of JavaScript files by removing unnecessary characters, comments, and whitespace, making the code more efficient for production environments.
What are gulp-uglify's main functionalities?
Basic Minification
This feature allows you to minify JavaScript files. The code sample demonstrates how to create a Gulp task that takes JavaScript files from the 'src' directory, minifies them using gulp-uglify, and outputs the minified files to the 'dist' directory.
const gulp = require('gulp');
const uglify = require('gulp-uglify');
gulp.task('minify-js', function() {
return gulp.src('src/*.js')
.pipe(uglify())
.pipe(gulp.dest('dist'));
});
Handling Errors
This feature demonstrates how to handle errors during the minification process. By using the 'gulp-plumber' package, you can prevent the Gulp process from stopping when an error occurs, allowing for smoother development workflows.
const gulp = require('gulp');
const uglify = require('gulp-uglify');
const plumber = require('gulp-plumber');
gulp.task('minify-js', function() {
return gulp.src('src/*.js')
.pipe(plumber())
.pipe(uglify())
.pipe(gulp.dest('dist'));
});
Source Maps
This feature allows you to generate source maps for the minified JavaScript files. Source maps help in debugging by mapping the minified code back to the original source code. The code sample shows how to initialize source maps, minify the JavaScript files, and write the source maps to the output directory.
const gulp = require('gulp');
const uglify = require('gulp-uglify');
const sourcemaps = require('gulp-sourcemaps');
gulp.task('minify-js', function() {
return gulp.src('src/*.js')
.pipe(sourcemaps.init())
.pipe(uglify())
.pipe(sourcemaps.write('./'))
.pipe(gulp.dest('dist'));
});
Other packages similar to gulp-uglify
terser
Terser is a JavaScript parser and mangler/compressor toolkit for ES6+. It is a popular alternative to UglifyJS and is known for its better support for modern JavaScript syntax. Terser can be used with Gulp through the 'gulp-terser' plugin, offering similar functionalities to gulp-uglify but with improved ES6+ support.
babel-minify
Babel-Minify is a minifier based on the Babel toolchain. It is designed to work seamlessly with Babel, making it a good choice for projects that already use Babel for transpiling. Babel-Minify can be integrated with Gulp using the 'gulp-babel-minify' plugin, providing an alternative to gulp-uglify with better integration for Babel users.
uglify-es
Uglify-ES is a fork of UglifyJS that adds support for ES6+ syntax. It is no longer actively maintained, but it was created to address the need for minifying modern JavaScript code. While gulp-uglify does not support ES6+ syntax, Uglify-ES can be used with Gulp through the 'gulp-uglify-es' plugin for projects that require ES6+ support.
gulp-uglify
Minify JavaScript with UglifyJS2.
Installation
Install package with NPM and add it to your development dependencies:
npm install --save-dev gulp-uglify
Usage
var uglify = require('gulp-uglify');
gulp.task('compress', function() {
gulp.src('lib/*.js')
.pipe(uglify())
.pipe(gulp.dest('dist'))
});
Options
-
mangle
Pass false
to skip mangling names.
-
output
Pass an object if you wish to specify additional output
options. The defaults are
optimized for best compression.
-
compress
Pass an object to specify custom compressor
options. Pass false
to skip
compression completely.
-
preserveComments
A convenience option for options.output.comments
. Defaults to preserving no
comments.
-
all
Preserve all comments in code blocks
-
some
Preserve comments that start with a bang (!
) or include a Closure
Compiler 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 either
true
or false
.
You can also pass the uglify
function any of the options listed
here to modify
UglifyJS's behavior.