mirror of
https://github.com/danog/inline-critical.git
synced 2024-11-30 04:29:07 +01:00
134 lines
3.4 KiB
JavaScript
134 lines
3.4 KiB
JavaScript
/**
|
|
* Module to inline styles while loading the existing stylesheets async
|
|
*
|
|
* @author Ben Zörb @bezoerb https://github.com/bezoerb
|
|
* @copyright Copyright (c) 2014 Ben Zörb
|
|
*
|
|
* Licensed under the MIT license.
|
|
* http://bezoerb.mit-license.org/
|
|
* All rights reserved.
|
|
*/
|
|
'use strict';
|
|
|
|
var _ = require('lodash');
|
|
var fs = require('fs');
|
|
var path = require('path');
|
|
var UglifyJS = require("uglify-js");
|
|
var cave = require('cave');
|
|
var reaver = require('reaver');
|
|
var cheerio = require('cheerio');
|
|
var render = require('dom-serializer');
|
|
var parse = require('cheerio/lib/parse');
|
|
var CleanCSS = require('clean-css');
|
|
var slash = require('slash');
|
|
var normalizeNewline = require('normalize-newline');
|
|
// get loadCSS
|
|
var loadCSS = read(path.join(__dirname, 'vendor', 'loadCSS.js'));
|
|
loadCSS = UglifyJS.minify(loadCSS, {fromString: true}).code;
|
|
|
|
/**
|
|
* Fixup slashes in file paths for windows
|
|
* @param {string} str
|
|
* @return {string}
|
|
*/
|
|
function normalizePath(str) {
|
|
return process.platform === 'win32' ? slash(str) : str;
|
|
}
|
|
|
|
/**
|
|
* Read file *
|
|
* @param {string} file
|
|
* @returns {string}
|
|
*/
|
|
function read(file) {
|
|
return fs.readFileSync(file, 'utf8');
|
|
}
|
|
|
|
|
|
module.exports = function (html, styles, options) {
|
|
|
|
if (!html) {
|
|
throw new Error('HTML missing!')
|
|
}
|
|
|
|
if (!styles) {
|
|
throw new Error('Styles missing!')
|
|
}
|
|
|
|
var $ = cheerio.load(String(html), {
|
|
decodeEntities: false
|
|
});
|
|
|
|
var links = $('link[rel="stylesheet"]').filter(function () {
|
|
return !$(this).parents('noscript').length;
|
|
});
|
|
var noscript = $('<noscript>\n</noscript>');
|
|
var o = options || {};
|
|
|
|
if (_.isString(o.ignore)) {
|
|
o.ignore = [o.ignore];
|
|
}
|
|
|
|
if (o.ignore) {
|
|
links = links.filter(function () {
|
|
var href = $(this).attr('href');
|
|
return _.findIndex(o.ignore, function (arg) {
|
|
return _.isRegExp(arg) && arg.test(href) || arg === href;
|
|
}) === -1;
|
|
});
|
|
}
|
|
|
|
// minify if minify option is set
|
|
if (o.minify) {
|
|
styles = new CleanCSS().minify(styles).styles;
|
|
}
|
|
|
|
// insert inline styles right before first <link rel="stylesheet" />
|
|
links.eq(0).before('<style type="text/css">\n' + styles + '\n</style>\n');
|
|
// insert noscript block right after stylesheets
|
|
links.eq(0).first().after(noscript);
|
|
|
|
var hrefs = links.map(function (idx, el) {
|
|
return $(this).attr('href');
|
|
}).toArray();
|
|
|
|
|
|
// extract styles from stylesheets if extract option is set
|
|
if (o.extract) {
|
|
if (!o.basePath) {
|
|
throw new Error('Option `basePath` is missing and required when using `extract`!');
|
|
}
|
|
hrefs = hrefs.map(function (href) {
|
|
var file = path.resolve(path.join(o.basePath, href));
|
|
if (!fs.existsSync(file)) {
|
|
return href;
|
|
}
|
|
var diff = normalizeNewline(cave(file, {css: styles}));
|
|
fs.writeFileSync(reaver.rev(file, diff), diff);
|
|
return normalizePath(reaver.rev(href, diff));
|
|
});
|
|
}
|
|
|
|
// wrap links to stylesheets in noscript block so that they will evaluated when js is turned off
|
|
links.each(function (idx) {
|
|
var el = $(this);
|
|
el.attr('href', hrefs[idx]);
|
|
noscript.append(el);
|
|
noscript.append('\n');
|
|
});
|
|
|
|
// build js block to load blocking stylesheets and insert it right before
|
|
$(noscript).before('<script>\n' +
|
|
'(function(u){' +
|
|
loadCSS +
|
|
'for(var i in u){loadCSS(u[i]);}' +
|
|
'}([\'' + hrefs.join('\',\'') + '\']));\n' +
|
|
'</script>\n');
|
|
|
|
|
|
var dom = parse($.html());
|
|
var markup = render(dom);
|
|
|
|
return new Buffer(markup);
|
|
};
|