Refactoring and Decoupling Rails controllers: can they call eachother?

I have the following situation in a Ruby on Rails app:

• user fills in a form (a comment), gets to see an omniauth page where she can choose the authentication method (openId, Twi开发者_C百科tter, Facebook and the likes).
• omniauth is filled in, on success user returns, gets a session and the initial form data is processed (comment is published).

I all works, except that I have my logic spread around in, what I consider, an ugly way; the SessionsController now creates the comment on successfull authentication.

What is a good way to decouple things like this? Should the Comment module hook into (listen to) the SessionsController? Or should the SessionsController simply call some methods on the CommentsController or Comment class to save a comment on successfull authentication? Are there any patterns that I can get myself familiar with, that solve these kind of issues?

I don't think it's necessarily good practice to call one controller from another, if you have shared functionality between controllers either use inheritance or a module. For your specific problem I'd do:

1. Unauthenticated user POSTS to /comments/create
2. A before filter checks for authentication and stores the comment params hash and the success redirect location in the session then redirects to /session/new
3. Upon successfully authenticating the session controller checks the params hash and creates any deferred models before redirecting to the stored path.

What would be great is if you could POST from another request, but unfortunately you can't, so you'll need to put the logic in the session controller.