Using MVC with an observer pattern, if a user action requires polling a device (such as a camera) for data, should the polling be done in the Controller and the result passed off the Model or should a request be sent to the Model and the Model itself performs the polling.
This question is my attempt to reconcile everything I am reading that touts the ‘skinny Controllers’ maxim with my gut intuition that the Model should only be acting on data not acquiring it.
(Note: This question might be subjective. I’m not entirely sure that there is a one-true-answer to this question. If not, feel free to retag as I will be very interested to hear opinions on the subject.)
It belongs in the controller. The model contains the information and business rules, the controller is essentially the interface to everything that is not the user, information, or a business rule, and the view deals with user interaction.
One might argue the view could control this as well – the camera model and drivers might be determined by the user, and thus fall under that area.
But I would not expect the model to have the peripheral interfaces.
-Adam