#penthouse
Critical Path CSS Generator
Penthouse is a tool generating critical path css for your web pages and web apps in order to speed up page rendering. Supply the tool with your site's full CSS, and the page you want to create the critical CSS for, and it will return all the CSS needed to render the above the fold content of the page. Read more about critical path css here.
The process is automatic and the generated css is production ready as is. If you run into problems however, check out the Problems section further down on this page.
Penthouse can be used:
- from the command line
- as a Node module
- as a Grunt task
- as a Gulp task (just require Node module straight from your script)
- via the online version
Install PhantomJS first, and make sure it works for you. Then download the penthouse.js file.
phantomjs penthouse.js [URL to page] [CSS file] > [critical path CSS file]
//for example
phantomjs penthouse.js http://mySite.com/page1 allStyles.css > page1-critical-styles.css
phantomjs penthouse.js http://mySite.com/page2 allStyles.css > page2-critical-styles.css
--width <width> The viewport width in pixels. Defaults to 1300
--height <height> The viewport height in pixels. Defaults to 900
To be able to run on all HTTPS sites two flags must be passed in, directly after phantomjs in the call:
--ignore-ssl-errors=true and --ssl-protocol=tlsv1
phantomjs penthouse.js [URL to page] [CSS file] [Viewport WIDTH] [Viewport HEIGHT] > [critical path CSS file]
npm install --save-dev penthouse
This will add penthouse to the list of dependencies
Require as normal and execute with a callback:
var penthouse = require('penthouse'),
path = require('path');
penthouse({
url : 'http://google.com',
css : path.join(__basedir + 'static/main.css'),
width : 1300, // viewport width
height : 900 // viewport height
}, function(err, criticalCss) {
if (err) { // handle error }
fs.writeFileSync('outfile.css', criticalCss);
});
The Penthouse Node module can also be used in Gulp.
http://jonassebastianohlsson.com/criticalpathcssgenerator/
###Background images or Fonts missing
Change any relative paths (f.e. background-image: url("../images/x.gif");) to absolute (starting with a /): background-image: url("/images/x.gif");, and then try again.
###Unstyled content showing If you for some reason have an element appearing early in the DOM, but that you apply styles to move outside of the above the fold content (using absolute position or transforms), consider whether it really should appear so early in the DOM.
###Special glyphs not showing/showing incorrectly
Problems with special characters like → after converting? Make sure you use the correct hexadecimal format in your CSS. You can always get this format from your browser console, by entering '→'.charCodeAt(0).toString(16) (answer for this arrow glyph is 2192). When using hexadecimal format in CSS it needs to be prepended with a backslash, like so: \2192 (f.e. content: '\2192';)
###Other problems Please report your issue (check that it's not already there first though!), and I will try to fix it as soon as possible.
2015-05-07 v0.3.2 Better error message when failing to open url (@pocketjoso)
2015-03-01 v0.3.1 Handle @-moz-document properly (@pocketjoso)
2015-02-14 v0.3.0 Better internal code, tests, remove printstyles (@fatso83, @pocketjoso)
2015-01-17 v0.2.53 Fix bug from 2.52, improved tests (@pocketjoso)
2015-01-11 v0.2.52 Fix minor removal bug with minified css (@pocketjoso)
2014-10-24 v0.2.51 Remove animation declarations (@pocketjoso)
2014-07-27 v0.2.5 Handle all non nested @-rules (@pocketjoso)
2014-07-20 v0.2.4 Fix extra line break bug on Windows (@pocketjoso)
2014-07-19 v0.2.3 Improved @-rule handling (@pocketjoso)
2014-07-12 v0.2.2 Remove :hover, and invalid, selectors (@pocketjoso)
2014-06-20 v0.2.1 Handle previous content clearing styles (@pocketjoso)
2014-06-10 v0.2.0 Node module and standalone executable (@fatso83)
2014-06-05 v0.1.0 Published on NPM (@pocketjoso)
2014-06-04 v0.0.0 PhantomJS script /core logic (@pocketjoso)