How to get AjaxScaffold working with Rails 1.2

Posted by Guy Naor Sat, 20 Jan 2007 22:05:37 GMT

Rails 1.2 was just released, and I decided to see how much pain it will be to make the help application work on it. As the application has a very good testing coverage (Code/Test LOC: 1:3.1) it is a good candidate to try with, as I can easily test most of the application using the automated tests.

I found a few deprecated things which I changed, and then some other routing problems and changes based on the new Prototype. It took some work, but wasn't too bad. One thing to note, is that you need to update Prototype to the latest from rails:

rake rails:update:javascripts

If you don't, the JavaScripts helpers will generate code that isn't compatible with the older Prototype.

After getting all tests to pass, and all deprecations warning taken care of, it was time for testing the UI in the browser, and this is where the "fun" started.

Not a single call to the AJAX requests made it to the server. It was just swallowed by Prototype. Luckilly FireBug makes JavaScript debugging tolerable. Using some console.log() calls, and the console in FireBug, I found there is an exception raised inside the Ajax.Request object. Some more logging, and I realised where the problem comes from: rico_corner.js used by AjaxScaffold is not compatible with the latest Prototype. It extends all the Prototype objects, and while doing it, extends an array that Prototype uses to set headers, adding to it a function that throws off the Prototype code completely.

There's a simple fix described here. It's kind of a hack, but at least will get you going for now.

Hope this saves you a few hours of head banging...