RESTful?

[Dark Tranquility]

So are you using REST? if yes for which situations do you think the REST approach works the best?

[Luke Redpath]

I'm trying out but remain slightly skeptical. I think I'm coming around but I'm still yet to see anybody talk about using it on anything but a simple app.

[Dark Tranquility]

I'm trying out but remain slightly skeptical. I think I'm coming around but I'm still yet to see anybody talk about using it on anything but a simple app.

what you are waiting for is exactly what I am looking for Luke!
REST doesn't seem to be that popular...does it?

[IAIHMB]

RPC is definitely more popular then REST, though I do believe that REST was gaining popularity before it was made an option in Rails 1.2. If i'm not mistaken .NET supported it, faking HTTP's DELETE and PUT as well (Heard it during David Hansson's Rails keynote, someone mentioned .NET's implementation and how bad it's faking was.). Amazon's S3 also offers a REST interface, though that really wasn't the question.

[Luke Redpath]

what you are waiting for is exactly what I am looking for Luke!
REST doesn't seem to be that popular...does it?

It does seem to be in the Rails community. I appear to be in the minority of those who remain skeptical.

Rails' PUT/DELETE faking is pretty simple really, its just a hidden form field in your form.

[Dark Tranquility]

Even Vinnie doesn't seem to like it

[Fenrir2]

I can think of many applications where REST works really well, but not of applications where it wouldn't work (applications that you'd use Rails for, not an online calculator for example). Does anyone have examples of applications where REST doesn't work?

[Luke Redpath]

I can think of many applications where REST works really well, but not of applications where it wouldn't work (applications that you'd use Rails for, not an online calculator for example). Does anyone have examples of applications where REST doesn't work?

Applications that have to follow a strict workflow (as part of the business rules) probably aren't a great fit for REST.

[vgarcia]

I like the concept of "simplify everything down to CRUD". I'm not 100% sold on the idea of having a REST API for every part of your webapp, but I also see it as of minor importance I guess.

[Fenrir2]

Applications that have to follow a strict workflow (as part of the business rules) probably aren't a great fit for REST.

Yes! Do you think it's a good idea to create a REST layer, and on top of that the actual application for the user? The workflow can be done by the topmost application, and you still have a REST API beneath that. You can then expose these APIs for users who want to create another front-end.

[Luke Redpath]

Well, whatever front end you have, it *must* interface with the workflow.

The important thing to remember about a workflow is that whilst it looks similar to a controller (i.e. it deals with the logic of where to go next) its actually part of the domain model. Any controller should simply delegate to the workflow to find out where to go next, then issue the redirect.

You could conceivelbly CRUD a Workflow object, updating the workflow with any important data, I suppose.

class WorkflowController < ActionController::Base
  before_filter :load_workflow, :except => [:new]
  after_filter :persist_workflow, :except => [:update, :delete]

  def new
    @workflow = Workflow.new
  end

  def show
    redirect_to :action => 'new' if @workflow.nil? and return
    @workflow.invoke(params[:step])
    render :template => params[:step]
  end

  def update
    @workflow.update(some_data)
    if @workflow.complete?
      redirect_to :action => 'destroy' and return
    end
    redirect_to :action => 'show, :step => @workflow.next_step
  end

  def destroy
    @workflow.destroy
  end

  protected
    def persist_workflow
      @workflow.save
      session[:workflow_id] = @workflow.id
    end

    def load_workflow
      @workflow = Workflow.find(session[:workflow_id])
    end
end