Rails 4 [Best practices] Nested resources and shallow: true

Question

The following post is based on Rails 4.

I am currently looking for a best-practice about the multiple nested resources (more than 1), and the option shallow: true.

Answer 1

Though it can complicate things if you only need this for some models, it might be good to check out Inherited Resources (IR). It supports resource nesting, polymorphic belongs to's, and can automatically generate the shorter path and url helper methods you are looking for. The reason you don't hear about IR much anymore is that its original author and some other developers have somewhat abandoned it because of the complications that arise when trying to extend your controllers. However, it still has a community, and we've tried to extend it a bit more and focus more on ease of controller extensions with Irie.

The "best practice" in Rails depends on who you talk to.

Rails has traditionally been aimed at mostly basic CRUD for (non-nested) resources. Yes, it allows retrieving and updating nested resources, but it is assumed that doesn't happen quite as often.

However, what has been emerging in the Rails community is the ActiveModel::Serializers/json-api approach. In this, usually not more than one level of nesting of resources occurs, and the nested resource is either a list of links or sideloaded small version of the child resources which you can then query on that resource to get more data. This has also been embraced by Ember/Ember Data.

There are also roar and a number of other projects that aim to implement something closer to their understanding of something close to Roy Fielding's original vision of REST.

I think it just depends on what your design is and what you need. If efficiency is a goal, then the additional time to develop to be explicit and nest more may pay off. We currently use AngularJS and Irie, for example. But, to each his own.

As as last note, be sure to avoid n+1 lookups through use of includes(...) (or similar) in your queries, otherwise all that nesting might bite you in performance.