Merge pull request #692 from cerebris/pr/651

Pr/651

Author: lgebhardt

README.md

@@ -214,6 +214,18 @@ class ContactResource < JSONAPI::Resource
 end
 ```
 
+##### Attribute Delegation
+
+Normally resource attributes map to an attribute on the model of the same name. Using the `delegate` option allows a resource
+attribute to map to a differently named model attribute. For example:
+
+```ruby
+class ContactResource < JSONAPI::Resource
+  attribute :name_first, delegate: :first_name
+  attribute :name_last, delegate: :last_name
+end
+```
+
 ##### Fetchable Attributes
 
 By default all attributes are assumed to be fetchable. The list of fetchable attributes can be filtered by overriding

lib/jsonapi/resource.rb

@@ -399,11 +399,11 @@ def attribute(attr, options = {})
         @_attributes ||= {}
         @_attributes[attr] = options
         define_method attr do
-          @model.public_send(attr)
+          @model.public_send(options[:delegate] ? options[:delegate].to_sym : attr)
         end unless method_defined?(attr)
 
         define_method "#{attr}=" do |value|
-          @model.public_send "#{attr}=", value
+          @model.public_send("#{options[:delegate] ? options[:delegate].to_sym : attr}=", value)
         end unless method_defined?("#{attr}=")
       end
 

test/unit/resource/resource_test.rb

@@ -33,6 +33,7 @@ class NoMatchAbstractResource < JSONAPI::Resource
 class CatResource < JSONAPI::Resource
   attribute :name
   attribute :breed
+  attribute :kind, :delegate => :breed
 
   has_one :mother, class_name: 'Cat'
   has_one :father, class_name: 'Cat'
@@ -175,7 +176,7 @@ def test_model_alternate
   def test_class_attributes
     attrs = CatResource._attributes
     assert_kind_of(Hash, attrs)
-    assert_equal(attrs.keys.size, 3)
+    assert_equal(attrs.keys.size, 4)
   end
 
   def test_class_relationships
@@ -255,14 +256,14 @@ def test_updatable_fields_does_not_include_id
   # TODO: Please remove after `updateable_fields` is removed
   def test_updateable_fields_delegates_to_updatable_fields_with_deprecation
     ActiveSupport::Deprecation.silence do
-      assert_empty(CatResource.updateable_fields(nil) - [:mother, :father, :name, :breed])
+      assert_empty(CatResource.updateable_fields(nil) - [:mother, :father, :name, :breed, :kind])
     end
   end
 
   # TODO: Please remove after `createable_fields` is removed
   def test_createable_fields_delegates_to_creatable_fields_with_deprecation
     ActiveSupport::Deprecation.silence do
-      assert_empty(CatResource.createable_fields(nil) - [:mother, :father, :name, :breed, :id])
+      assert_empty(CatResource.createable_fields(nil) - [:mother, :father, :name, :breed, :id, :kind])
     end
   end