support passing links hash to a relationship and more tests

Author: tchak

lib/active_model/serializer/adapter/json_api.rb

@@ -177,7 +177,19 @@ def relationship_value_for(serializer, options = {})
         end
 
         def relationship_links_for(name, serializer, options = {})
-          { related: url_helper.url_for([serializer.object, name]) }
+          if options[:links] == true
+            { related: url_helper.url_for([serializer.object, name]) }
+          else
+            options[:links].inject({}) do |hash, (key, link)|
+              hash[key] = if link.is_a? Proc
+                link.call(serializer.object, name)
+              else
+                link
+              end
+
+              hash
+            end
+          end
         end
 
         def relationships_for(serializer)

test/adapter/json_api/has_many_url_test.rb

@@ -2,7 +2,38 @@
 
 module ActionController
   module Serialization
-    class JsonApiHasManyUrlTest < ActionController::TestCase
+    class JsonApiHasManyUrlNoDataLinksTest < ActionController::TestCase
+      class MyController < ActionController::Base
+
+        def render_resource_with_url_association
+          @tag = Tag.new(id: 1)
+          @tag.posts = []
+          render json: @tag, adapter: :json_api, serializer: LinkNoDataTagSerializer
+        end
+      end
+
+      tests MyController
+
+      def test_render_resource_with_url_association
+        get :render_resource_with_url_association
+        expected = {
+          data: {
+            id: "1",
+            type: "tags",
+            relationships: {
+              posts: {
+                links: {
+                  related: "http://test.host/tags/1/posts"
+                }
+              }
+            }
+          }
+        }
+        assert_equal expected.to_json, response.body
+      end
+    end
+
+    class JsonApiHasManyUrlDataLinksTest < ActionController::TestCase
       class MyController < ActionController::Base
 
         def render_resource_with_url_association
@@ -22,6 +53,7 @@ def test_render_resource_with_url_association
             type: "tags",
             relationships: {
               posts: {
+                data: [],
                 links: {
                   related: "http://test.host/tags/1/posts"
                 }
@@ -32,5 +64,67 @@ def test_render_resource_with_url_association
         assert_equal expected.to_json, response.body
       end
     end
+
+    class JsonApiHasManyUrlLinkTest < ActionController::TestCase
+      class MyController < ActionController::Base
+
+        def render_resource_with_url_association
+          @tag = Tag.new(id: 1)
+          @tag.posts = []
+          render json: @tag, adapter: :json_api, serializer: LinkUrlTagSerializer
+        end
+      end
+
+      tests MyController
+
+      def test_render_resource_with_url_association
+        get :render_resource_with_url_association
+        expected = {
+          data: {
+            id: "1",
+            type: "tags",
+            relationships: {
+              posts: {
+                links: {
+                  related: "http://test.host/post_tags"
+                }
+              }
+            }
+          }
+        }
+        assert_equal expected.to_json, response.body
+      end
+    end
+
+    class JsonApiHasManyUrlLinkProcTest < ActionController::TestCase
+      class MyController < ActionController::Base
+
+        def render_resource_with_url_association
+          @tag = Tag.new(id: 1)
+          @tag.posts = []
+          render json: @tag, adapter: :json_api, serializer: LinkProcTagSerializer
+        end
+      end
+
+      tests MyController
+
+      def test_render_resource_with_url_association
+        get :render_resource_with_url_association
+        expected = {
+          data: {
+            id: "1",
+            type: "tags",
+            relationships: {
+              posts: {
+                links: {
+                  related: "http://test.host/tags/1/posts/all"
+                }
+              }
+            }
+          }
+        }
+        assert_equal expected.to_json, response.body
+      end
+    end
   end
-end
+end

test/fixtures/poro.rb

@@ -253,9 +253,21 @@ def self.root_name
 end
 
 LinkTagSerializer = Class.new(ActiveModel::Serializer) do
+  has_many :posts, links: true
+end
+
+LinkNoDataTagSerializer = Class.new(ActiveModel::Serializer) do
   has_many :posts, links: true, data: false
 end
 
+LinkUrlTagSerializer = Class.new(ActiveModel::Serializer) do
+  has_many :posts, links: { related: 'http://test.host/post_tags' }, data: false
+end
+
+LinkProcTagSerializer = Class.new(ActiveModel::Serializer) do
+  has_many :posts, links: { related: -> (object, name) { "http://test.host/tags/#{object.id}/#{name}/all" } }, data: false
+end
+
 VirtualValueSerializer = Class.new(ActiveModel::Serializer) do
   attributes :id