Antonio Gallardo wrote: > Please see the report below. Comments? <snip/> > > http://cocoon.zones.apache.org/demos/21branch/_cocoon/resources/dojo/dojo.js > 145 kb
Dojo is a highly modular toolkit, which can load new JS scripts on demand (using Ajax requests). However, loading individually each and every module leads to an important overhead in page load time. To solve this, Dojo provides a "compressor" [1] that assembles a set of modules (JS files) in an single dojo.js file and compresses it (removes whitespace and comments, shortens identifiers). Browsers will then cache this dojo.js file, so that only the first use is costly. The work of the compressor is driven by a "profile" where you describe what modules you want to integrate in that single file. For Cocoon, I used the "widget" profile which includes the base infrastructure and a number of widgets (see blocks/ajax/dojo/build.xml). The actual profile to be used in a production system should normally be adapted to the actual modules your application uses to achieve maximum performance. We cannot guess within Cocoon what this module set will be, but what we can do is define a profile containing only the Dojo features that are effectively used by what we provide (i.e. the widgets in the forms and ajax blocks). That may allow to have a smaller default dojo.js, while still leaving room for people to build their own version of dojo.jar with their own profile. BTW, Dojo's is very successful, and some CDNs are providing it [2], thus allowing applications to load the full dojo.js from a central location. One single cached JS files served by distributed servers for many unrelated web sites! [1] http://dojotoolkit.org/docs/compressor_system.html [2] http://blog.dojotoolkit.org/2006/01/30/dojo-iamalpha-and-cdns -- Sylvain Wallez http://bluxte.net Apache Software Foundation Member
