There is a terminology problem in the Rails community.
Everyone promotes Rails as a MVC framework. I did that as well. However, the truth is that Rails represents the Model2 architecture. It's not MVC.
OK, so what's the difference?
In short, we're talking about MVC when a model can notify (through the Observer pattern) the views about the changes. It's not possible in a classical Rails app (it's possible when you use WebSockets, Pusher or a similar technology, but it's not so popular yet.). MVC was popular in desktop apps.
On the other hand, Model2 is exactly what we do with Rails. We don't notify the views from the model, the controller simply passes the model data to the views and handles the html generation which is then sent to the browser.
There's an interesting pattern evolving recently that a Rails app simply serves as a backend for a mobile app and all it does is exposing a JSON/REST API. It's similar to Model2, but instead of generating HTML it generates JSON. Still, it's not MVC.
You can read more about UI architectures in this article by Martin Fowler
Why is it important?
What shall we do about the Model2 and MVC confusion?
I see three choices.
The first one is to say that MVC changed its original meaning and Model2 can also be called MVC. In that case we can start using terms like "classic MVC" or "real MVC" for the old MVC. This is what is happening now, but I don't think that changing definitions is a good idea. It brings even more confusion.
The second way is to promote the fact that Rails represents a Model2 architecture and MVC is reserved to, well, MVC. It's going to be hard, but we will keep the definitions stable.
The third way is to just ignore the confusion. Who cares?
I decided to go with the second option. What's the best way in your opinion?
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