问题:

There is all sorts of talk lately in the Ruby on Rails community about decorators and presenters.

What is the essential difference between the two? If there is, what are the clues that tell me which one to use over the other? Or perhaps to use the two in conjunction?

回答1:

A decorator is more of a "let's add some functionality to this entity". A presenter is more of a "let's build a bridge between the model/backend and view". The presenter pattern has several interpretations.

Decorators are generic/general purpose. Presenters have a narrower range of responsibilities/uses. Decorators are used across domains, presenters are almost always related to view-like functionality.

Draper site
RailsCasts Draper Episode

回答2:

I suggest you to check this - Exhibit vs Presenter.

Decorator is a design pattern that is used to extend the functionality of a specific object by wrapping it, without effecting other instances of that object. In general, the decorator pattern is an example of the open/close principle (the class is closed for modifications, but available for extensions).

Both the exhibit and presenter patterns are a kind of the decorator pattern.