Frontend performance enhancements with admin2++ eZ Publish extension

About a month ago, I created a new project called admin2++ on projects.ez.no. As written in the project page, the purpose of this project is to go further in the administration interface refresh both on the frontend performance and on the features for users to achieve what I wrote last november on the admin interface refresh of eZ Publish. On the frontend performance side, changes are quite hidden but are there, so it's time to do some advertising :-) In fact, it's more or less an application of my talk in Geneva on frontend performance with eZ Publish.

Current enhancements on frontend performance

The admin2++ extension provides the following enhancements to eZ Publish admin2 interface :

  • the twenties background images have been incorporated into three sprites images to decrease the number of HTTP requests. This also decreases the total background images size from about 30Kb to 6Kb.
  • PNG Content class icons and PNG admin2 design images have been optimized. Here again the total size of icons and images is decreased from about 200Kb to 147Kb.
  • the admin2++ extension provides parts of Apache2 config files to enable GZip compression and set a far future Expires header where possible
  • I also replaced the code using YUI3 (drag'n drop of sub-items when sorting with priority) or YUI2 (Date picker) JavaScript frameworks by a code based on jQuery and jQueryUI as jQuery is used for most features of admin2 and jQueryUI is used for others features provided by the extension. This avoids loading three JavaScript frameworks.
  • Most of the JavaScript code executed in page has been deferred to DOM ready event instead of DOM load.
  • The login page preloads the most used images and all the JavaScript files needed by the admin interface. I tried to configure eZ Publish/eZJSCore so that the JavaScript pack file generated by eZJSCore operators is the same on all pages. The browser downloads the JavaScript on the login page and then it always uses its cache on others pages. I'm happy to see that a part of this has been ported in the eZ Publish trunk :-)

What is missing, future developments ?

I wanted to override ezdesign and ezimage operators to automatically add the last modification date of a ressource in file URI so a far future header can be set on all design ressources without any browser cache issue. Unfortunately, overriding template operators is not possible for the moment. Currently, the expires is set to only seven days in expires.conf provided in the extension for most design ressources.

In addition, a lot of others small improvements would be possible like minifying inline JavaScript code or part of the HTML itself, ... and as usual, it lacks some documentation on how to set it up.