Wrapping a RESTful Rails API in FLEX

A little while back I was talking about getting started with writing an Air app in flex that talks to a Rails backend and some of the troubles I was having.  I've been working on and off trying to fine tune what I started out with and turn it into a set of base classes for wrapping a restful api (based on the rails conventions).  I've finally got something, it's not ideal and it's really not how I would have liked he design to turn out, but it's better than anything I've come up with along the way.

I'll start out with how I would have like this little framework to have turned out.  What I was really looking for was a couple of base classes that defined the basic REST actions as well as some unifying way to dispatch and listen for events on the api.

The second problem, 'event management' I guess, wasn't too hard to solve, I created a Singleton (sort of, AS3 doesn't really let you do this, but you can kind of fake it) that extended from EventDispatcher and then added and made dispatch calls on the instance.  My class making the REST calls now needed to know about this 'Controller' class to be able to do the event dispatching, it also made sense to define the endpoint url here.

Now, the main problem I was trying to solve, having a base class to define the REST calls, kept giving me trouble.  At first defining instance methods for create, destroy, etc made sense but then as I started using the class having create as an instance method really didn't make sense; create is building the object instance and should be a static class method.  This is where my trouble started, since create (and get) actions should be static, if I wanted to define the logic in the base class then my subclass would still need to provide a wrapping method, or I'd be calling something like Base.create("object\_type") everywhere, which didn't really seem right to me.  This lead me down a long road of messing this reflection classes, and introspection methods (which are awful in AS3 in my opinion) causing a lot of ugly code and me to become frustrated with my solution.

After messing about like this for three separate coding sessions I had enough and decided to get back to what it needs to do; blew away the base classes and brought everything into the main class (for now this was the Session) and structured things the way I wanted it to look for a client of the api.  Once I got things working again it was again obvious that some things could be abstracted away, but I still have the problem that some api calls should be static and some not; which would pull me into the same mess as before with a base class.

So, Instead of doing that I created an object that wrapped up all the rest services into a single package then I created a static instance variable of this 'ResourceHandler' inside my Session class and delegated the work to it.  Now, this isn't as easy as extending from a class and overriding a couple of methods, but it does hide away all the HTTPService definitions, adding and removing event listeners, and other redundancies from the classes.

I still think there should be a cleaner way to do some of this in AS3, maybe I just don't know the language well enough though.  Part way through I did find another framework that was trying to implement ActiveResource in AS3, but the project doesn't look very active anymore.  I'll post a little walkthrough of how the classes work in a bit, it's still not complete yet but if you want to take a look at the code in the meantime leave a comment.