I have an application, built using MVC, that produces a view which delivers summary information across a number of models. Further to that, some calculations are performed across the different sets of data.
There’s no clear single model (that maps to a table at least) that seems to make sense as the starting point for this, so the various summaries are pulled from the contributing models in the controller, passed into the view and the calculations are performed there.
But that seems, well, dirty. But controllers are supposed to be lightweight, aren’t they? And business logic shouldn’t be in views, as I have it as present.
So where should this information be assembled? A new model, that doesn’t map to a table? A library function/module? Or something else?
(Although I see this as mostly of an architectural/pattern question, I’m working in Rails, FWIW.)
Edit: Good answers all round, and a lot of consensus, which is reassuring. I ‘accepted’ the answer I did to keep the link to Railscasts at the top. I’m behind in my Railscast viewing – something I shall make strenuous attempts to rectify!
As Brian said, you can create another model that marshals out the work that needs doing. There is a great Railscast on how to do this type of thing.
HTH