Monday, September 26, 2011

Integrating YUI3 with Tapestry 5.2

I have become a fan of the YUI's patterns for modular architecture and the idea of executing JavaScript in a restricted "sandbox". Unfortunately, I haven't found many examples for integrating this pattern in Tapestry 5.2. The closest example for integrating YUI at the time was the tapx-yui module, but as the project is more related to YUI 2, I thought to give it a go and try to implement something for YUI 3 myself.

Step 1: importing YUI JavaScript modules and CSS
As far as I've understood, there are two ways for importing YUI modules:
  1. By importing (creating a script tag for) every YUI JavaScript asset that is required on a page.
  2. By importing the yui(-min).js asset and using the auto-loading feature.
As tapx-yui already had a great example on how to go about importing the assets one-by-one, I decided to focus on using the auto-loader approach. In the following example, I define the yui.js asset as a JavaScriptStack, which also contains 4 YUI CSS assets: cssreset, cssbase, cssfonts and cssgrids. No real reason to do so, the CSS assets could as well be auto-loaded.

In this case, all assets from the YUI build are expected to be stored under the src/main/webapp/yui directory.
The CoreYuiStack class needs to be contributed to the JavaScriptStackSource service:

Step 2: Creating a component that defines a YUI module
As soon as YUI libraries can be auto-loaded, we can start defining our own custom modules. Here is an example of a component that wraps the YUI Panel functionality. Not much augmentation here compared to the YUI's Panel, but the idea should be clear enough.

A new JavaScript namespace, appcore is defined, containing a component called Panel. The corresponding Tapestry component class looks like this:

After the component's body is rendered, we add an initialization call for passing configuration data to the new component. There is no special API here, just a simple code snippet rendered into the page body. There is some room for improvement here. Although we would very much like the initialization call to be wrapped in a sandbox, the dependency on a local variable called Y looks a bit iffy design-wise.
The YuiSupport service is responsible for wrapping the initialization calls into a YUI sandbox:

Step 3: Using the new component
The Panel component can now be used like any other Tapestry component:
The output should now contain a panel similar to this:


Good news, everyone! There's another blog on the Interwebs that mostly consists of written thoughts of a random dude who is a fan of software design and development, but also computer gaming, music and comedy. This blog.

You might find something interesting, useful or amusing here if You take interest in any of the following: software development and design (architecture), developer productivity, computer and video gaming, computer game development, somewhat outdated music, stand-up comedy or cartoons.

Many thanks for visiting. Your feedback is appreciated.