Reactive Resource¶ ↑

Reactive Resource is a useful collection of extensions extracted from ActiveResource wrappers around various APIs. Among other things, it adds belongs_to, has_one, and has_many relationships to ActiveResource models and has significantly better support for one-to-one relationships.

After installing the gem, your ActiveResource models should inherit from ReactiveResource::Base instead of ActiveResource::Base.

The most useful thing Reactive Resource adds to ActiveResource is read support for associations. This allows you to specify relationships between objects:

class ReactiveResource::Lawyer < ReactiveResource::Base
  has_many :addresses
end

class ReactiveResource::Address < ReactiveResource::Base
  belongs_to :lawyer
  has_many :phones
end

class ReactiveResource::Phone < ReactiveResource::Base
  belongs_to :address
end

and allows you to make calls like:

ReactiveResource::Lawyer.find(1).addresses.first.phones

This also takes care of URL generation for the associated objects, so the above command will hit /lawyers/1.json, then /lawyers/1/addresses.json, then /lawyers/1/addresses/:id/phones.json.

Currently, Reactive Resource only supports ‘read-style’ associations. It does not yet support things like build_association and association=.

One thing ActiveResource was lacking was good support for generating nested paths for child resources. Reactive Resource uses the belongs_to declarations to generate paths like /lawyers/1/addresses.json, without having to specify all the paths in each class.

For singleton resources, ActiveResource would still use the plural and generate paths like /lawyers/1/headshots.json. I didn’t like this, so you can now mark a resource as a singleton resource:

class ReactiveResource::Headshot < ReactiveResource::Base
  singleton
end

and the paths will be generated correctly. This is based on the patch at rails.lighthouseapp.com/projects/8994/tickets/4348-supporting-singleton-resources-in-activeresource

In ActiveResource, if you had nested URLs specified in the resource path in your class definition, you had to set those params at the object’s creation time. Reactive Resource allows you to set those parameters at any time after object creation.