A Browserify transform for bundling, rebasing, inlining, and minifying CSS files
npm install browserify-css
A Browserify transform for bundling, rebasing, inlining, and minifying CSS files. It's useful for CSS modularization where styles are scoped to their related bundles.
If you're new to browserify, check out the browserify handbook and the resources on browserify.org.
npm install --save-dev browserify-css
app.css:
`` css`
@import url("modules/foo/index.css");
@import url("modules/bar/index.css");
body {
background-color: #fff;
}
app.js:
` js`
var css = require('./app.css');
console.log(css);
You can compile your app by passing -t browserify-css to browserify:
` bash`
$ browserify -t browserify-css app.js > bundle.js
Each require('./path/to/file.css') call will concatenate CSS files with @import statements, rebasing urls, inlining @import, and minifying CSS. It will add a style tag with an optional data-href attribute to the head section of the document during runtime:
` html`
You can set configuration to your package.json file:
` json`
{
"browserify-css": {
"autoInject": true,
"minify": true,
"rootDir": "."
}
}
or use an external configuration file like below:
` json`
{
"browserify-css": "./config/browserify-css.js"
}
config/browserify-css.js:
` js`
module.exports = {
"autoInject": true,
"minify": true,
"rootDir": "."
};
Furthermore, browserify-css transform can obtain options from the command-line with subarg syntax:
`
$ browserify -t [ browserify-css --minify=true --output bundle.css ] -o bundle.js app.js
or from the api:
b.transform('browserify-css', {
minify: true,
output: 'bundle.css'
});
Type: Boolean
Default:
If true, each require('path/to/file.css') call will add a style tag to the head section of the document.
Type: Object
Default: js`
{
"verbose": true,
"insertAt": "bottom" // or "top"
}
#### verbose
If verbose is set to true, the path to CSS will be specified in the data-href attribute inside the style tag
#### insertAt
By default, browserify-css transform appends <style> elements to the end of the <head> tag of the page. This will cause CSS created by browserify-css transform to take priority over CSS already present in the document head. To insert style elements at the beginning of the head, set the insertAt parameter to 'top'.
Type: Boolean or Object
Default:
If true, each required css file will have image url() replaced with data urls. For example from:
`css`
background-image: url("background.png");
to:
`css`
background-image: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAVQAAAHgCAYAAAD6yZXWAAAABmJLR0QA");
Type: Object
Default:
`js`
{
// maximum size (in bytes) of image file that will be inlined into css file
"limit": 0 // 0 means no limit - inline all images
}
If a limit is set, then only files that are smaller than the number of bytes given will be inlined into the css file.
Type: Boolean
Default:
Type: Object
Default:
Check out a list of CSS minify options at CleanCSS.
Type: Function
The onFlush option accepts a function which takes two arguments: (options, done).`js`
// @param {object} options The options object
// @param {string} options.filename The filename
// @param {string} options.data The CSS file content
// @param {string} options.rootDir The root directory
// @param {string} options.relativePath The relative path
// @param {string} options.href The href attribute
// @param {function} done The done callback
onFlush: function(options, done) {
// Method 1:
// This will keep original module.exports unchanged
done();
// Method 2:
// Pass a null value to the done callback if you do not want to embed CSS into a JavaScript bundle
done(null);
// Method 3:
// Pass a text string to the done callback to customize module.exports
done('module.exports = ' + JSON.stringify(options.data) + ';');
}
You can use the onFlush option to output each CSS to a separate file, or append multiple CSS into one file. For example:` javascript
var browserify = require('browserify');
var fs = require('fs');
fs.unlinkSync('dist/assets/app.css');
browserify(options)
.add('src/index.js')
.transform(require('browserify-css'), {
rootDir: 'src',
onFlush: function(options, done) {
fs.appendFileSync('dist/assets/app.css', options.data);
// Do not embed CSS into a JavaScript bundle
done(null);
}
})
.bundle();
`
Type: String
Default: ''
The output path of the CSS file. When using this option, browserify-css will not embed stylesheets into a JavaScript bundle.
`bash`
browserify -t [ browserify-css --minify=true --output bundle.css ] -o bundle.js index.js
Type: Function
The processRelativeUrl option accepts a function which takes one argument (the relative url) and returns the original relativeUrl string or the converted result. For example:` javascript
var browserify = require('browserify');
browserify(options)
.add('src/index.js')
.transform(require('browserify-css'), {
rootDir: 'src',
processRelativeUrl: function(relativeUrl) {
return relativeUrl;
}
})
.bundle();
`
You can embed the image data directly into the CSS file with data URI, like so:
` javascript
var _ = require('lodash');
var path = require('path');
var browserify = require('browserify');
browserify(options)
.add('src/index.js')
.transform(require('browserify-css'), {
rootDir: 'src',
processRelativeUrl: function(relativeUrl) {
if (_.contains(['.jpg','.png','.gif'], path.extname(relativeUrl))) {
// Embed image data with data URI
var DataUri = require('datauri');
var dUri = new DataUri(relativeUrl);
return dUri.content;
}
return relativeUrl;
}
})
.bundle();
`
You may also want to check out the FAQ for advanced usage.
Type: Boolean
Default:
If true, relative paths will be rebased in css files; if false, paths will be unchanged.
Type: String
Default:
An absolute path to resolve relative paths against the project's base directory.
Type: Boolean
Default:
Strip comments from CSS. Defaults to false.
1. The easiest way to do this is using the @import rule. For example:
app.js:
` javascript`
require('./app.css');
app.css:
` css
/ Use CSS from your node_modules folder /
@import "node_modules/foo/foo.css";
/ Or your own relative files /
@import "styles/common.css";
`
2. Use the global transform option (i.e. or -g) on the command line to transform all files in a node_modules directory:
` bash`
$ browserify -g browserify-css app.js > bundle.js
or use the API directly:
` javascript`
var browserify = require('browserify');
var b = browserify('./app.js');
b.transform('browserify-css', {global: true});
b.bundle().pipe(process.stdout);
See browserify transform options for details.
Then you will be able to require CSS files from within node_modules. For example:
javascript`
require('bootstrap/dist/bootstrap.css');
3. Put browserify transform option into a submodule's package.json file inside the node_modules directory on a per-module basis like so:
node_modules/foo/package.json:
` json`
{
"browserify": {
"transform": ["browserify-css"]
}
}
Then, run browserify transform on the command line:
` bash`
$ browserify -t browserify-css app.js > bundle.js
Assume that you have the following directory structure:
` bash`
package.json
dist/
src/
index.js
index.css
node_modules/
bootstrap/
dist/
css/
bootstrap.css
The index.css uses @import to import external style sheets:` css`
@import url("../node_modules/bootstrap/dist/css/bootstrap.css");
All output files, including the generated bundle.js, are created under the dist directory:` bash`
dist/
bundle.js
vendor/
bootstrap/
dist/
css/
bootstrap.css
Suppose that the dist directory is your web root, you might want to copy external font and images files from ../node_modules/ to dist/vendor/.
For example, the @font-face rules in node_modules/bootstrap/dist/css/bootstrap.css:` css`
@font-face {
font-family: 'Glyphicons Halflings';
src: url('../fonts/glyphicons-halflings-regular.eot');
src: url('../fonts/glyphicons-halflings-regular.eot?#iefix') format('embedded-opentype'),
url('../fonts/glyphicons-halflings-regular.woff2') format('woff2'),
url('../fonts/glyphicons-halflings-regular.woff') format('woff'),
url('../fonts/glyphicons-halflings-regular.ttf') format('truetype'),
url('../fonts/glyphicons-halflings-regular.svg#glyphicons_halflingsregular') format('svg');
}
The example below illustrates the use of the processRelativeUrl option:` javascript
var gulp = require('gulp');
var gutil = require('gulp-util');
var path = require('path');
var browserify = require('browserify');
var sourceStream = require('vinyl-source-stream');
var fse = require('fs-extra');
var bundleStream = browserify()
.add('src/index.js')
.transform(require('browserify-css'), {
rootDir: 'src',
processRelativeUrl: function(relativeUrl) {
var stripQueryStringAndHashFromPath = function(url) {
return url.split('?')[0].split('#')[0];
};
var rootDir = path.resolve(process.cwd(), 'src');
var relativePath = stripQueryStringAndHashFromPath(relativeUrl);
var queryStringAndHash = relativeUrl.substring(relativePath.length);
//
// Copying files from '../node_modules/bootstrap/' to 'dist/vendor/bootstrap/'
//
var prefix = '../node_modules/';
if (_.startsWith(relativePath, prefix)) {
var vendorPath = 'vendor/' + relativePath.substring(prefix.length);
var source = path.join(rootDir, relativePath);
var target = path.join(rootDir, vendorPath);
gutil.log('Copying file from ' + JSON.stringify(source) + ' to ' + JSON.stringify(target));
fse.copySync(source, target);
// Returns a new path string with original query string and hash fragments
return vendorPath + queryStringAndHash;
}
return relativeUrl;
}
})
.bundle();
bundleStream
.pipe(sourceStream(bundleFile))
.pipe(gulp.dest(browserifyConfig.dest));
``
Test Images:
- test/fixtures/background.png
Originally by W3C under terms of CC-BY-3.0, via Wikimedia Commons
- test/fixtures/background-600.png
Originally by Rudloff under terms of CC-BY-3.0, via Wikimedia Commons
MIT