critical-css-parser
Advanced tools
Get critical (above-the-fold) and the rest CSS using Puppeteer.
Critical-css-parser allows you to receive critical (above-the-fold) and the rest CSS. It might be helpful to speed up initial rendering of a web page. More information.
There are 3 types of input information: HTML and CSS, URL and localServer.
Critical-css-parser uses Puppeteer and DropCSS under the hood, so IT ALSO SUPPORTS ADAPTIVE DESIGN (BOTH DESKTOP AND MOBILE VERSIONS)! It also supports minifying (by CSSO).
This library is part of other projects: critical-css-inliner, webpack-critical-css-inliner
npm install --save-dev critical-css-parser
// or
yarn add --dev critical-css-parser
const criticalCSSParser = require('critical-css-parser');
(async () => {
const result = await criticalCSSParser({
type: 'URL',
URL: 'https://abvcss.github.io/abvcss-website/', // try to check your site
enableGoogleFonts: false,
whitelist: /#foo|\.bar/
});
console.log(result.critical); // ''
console.log(result.rest); // ':not(pre)>code[class*=language-]{background:#272822}:not(pre)>code[class*=language-]{'
})();
const criticalCSSParser = require('critical-css-parser');
(async () => {
const result = await criticalCSSParser({
type: 'localServer',
entrypoint: './www',
filename: 'index.html',
enableGoogleFonts: true
});
console.log(result.critical); // 'html{font-size: 10pt;}div{color: red;}'
console.log(result.rest); // 'p{color: red;}'
})();
const criticalCSSParser = require('critical-css-parser');
const html = `
<html>
<head></head>
<body>
<p>Hello <a href="#">World!</a></p>
</body>
</html>
`;
const css = `
.card {
padding: 8px;
}
p:hover a:first-child {
color: red;
}
`;
(async () => {
const result = await criticalCSSParser({
type: 'HTML',
html,
css,
minify: true // good way to optimize size
});
console.log(result.critical); // 'p:hover a:first-child{color:red}'
console.log(result.rest); // '.card{padding:8px}'
})();
Pass options to criticalCSSParser({ ... }).
Parameters
optionsProperties
type String One of: HTML, URL or localServer. REQUIRED
html String Your custom html code (default: '') REQUIRED FOR type === HTML
css String Your custom css code (default: '') REQUIRED FOR type === HTML
URL String URL of the page you need to optimize (default: '') REQUIRED FOR type === URL
entrypoint String Root of your application (default: '') REQUIRED FOR type === localServer
filename String Your index file (default: 'index.html')
enableGoogleFonts Boolean Set true to except Google Font styles (default: false)
whitelist RegExp Whitelist of the critical CSS (default: /#fooBazBarAboveTheFold8917/)
minify Boolean Set true to minify resulting styles (default: false)
<Promise<{ critical, rest }>>
critical - above-the-fold CSS. These styles you can put into your <style> tag.
rest - other CSS. You can lazy-load the rest like this.
MIT license
FAQs
Get critical (above-the-fold) and the rest CSS using Puppeteer.
The npm package critical-css-parser receives a total of 45 weekly downloads. As such, critical-css-parser popularity was classified as not popular.
We found that critical-css-parser demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 1 open source maintainer collaborating on the project.
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