fixes #982 fix relationship linkage

when belongs_to relationship has overridden primary_key
when polymorphic relationship has overridden primary_key
add tests

Author: senid231

lib/jsonapi/relationship.rb

@@ -64,6 +64,10 @@ def readonly?
       @options[:readonly]
     end
 
+    def redefined_pkey?
+      belongs_to? && primary_key != resource_klass._default_primary_key
+    end
+
     class ToOne < Relationship
       attr_reader :foreign_key_on
 

lib/jsonapi/resource.rb

@@ -783,7 +783,11 @@ def _model_name
       end
 
       def _primary_key
-        @_primary_key ||= _model_class.respond_to?(:primary_key) ? _model_class.primary_key : :id
+        @_primary_key ||= _default_primary_key
+      end
+
+      def _default_primary_key
+        @_default_primary_key ||=_model_class.respond_to?(:primary_key) ? _model_class.primary_key : :id
       end
 
       def _cache_field

lib/jsonapi/resource_serializer.rb

@@ -454,7 +454,7 @@ def link_object(source, relationship, include_linkage = false)
     def foreign_key_value(source, relationship)
       related_resource_id = if source.preloaded_fragments.has_key?(format_key(relationship.name))
         source.preloaded_fragments[format_key(relationship.name)].values.first.try(:id)
-      elsif source.respond_to?(relationship.foreign_key)
+      elsif !relationship.redefined_pkey? && !relationship.polymorphic? && source.respond_to?(relationship.foreign_key)
         # If you have direct access to the underlying id, you don't have to load the relationship
         # which can save quite a lot of time when loading a lot of data.
         # This does not apply to e.g. has_one :through relationships.

test/fixtures/access_cards.yml

@@ -0,0 +1,4 @@
+john_doe_worker_card:
+  id: 1
+  token: "some-token"
+  security_level: "admin"

test/fixtures/active_record.rb

@@ -310,7 +310,30 @@
     t.string :name
   end
 
-  # special cases
+  create_table :storages, force: true do |t|
+    t.string :token, null: false
+    t.string :name
+    t.timestamps null: false
+  end
+
+  create_table :keepers, force: true do |t|
+    t.string :name
+    t.string :keepable_type, null: false
+    t.integer :keepable_id, null: false
+    t.timestamps null: false
+  end
+
+  create_table :access_cards, force: true do |t|
+    t.string :token, null: false
+    t.string :security_level
+    t.timestamps null: false
+  end
+
+  create_table :workers, force: true do |t|
+    t.string :name
+    t.integer :access_card_id, null: false
+    t.timestamps null: false
+  end
 end
 
 ### MODELS
@@ -655,6 +678,22 @@ class Customer < Customer
   end
 end
 
+class Storage < ActiveRecord::Base
+  has_one :keeper, class_name: 'Keeper', as: :keepable
+end
+
+class Keeper < ActiveRecord::Base
+  belongs_to :keepable, polymorphic: true
+end
+
+class AccessCard < ActiveRecord::Base
+  has_one :worker, class_name: 'Worker'
+end
+
+class Worker < ActiveRecord::Base
+  belongs_to :access_card
+end
+
 ### CONTROLLERS
 class AuthorsController < JSONAPI::ResourceControllerMetal
 end
@@ -930,6 +969,17 @@ class DoctorsController < JSONAPI::ResourceController
 class RespondentController < JSONAPI::ResourceController
 end
 
+class StoragesController < BaseController
+end
+
+class KeepersController < BaseController
+end
+
+class AccessCardsController < BaseController
+end
+
+class WorkersController < BaseController
+end
 ### RESOURCES
 class BaseResource < JSONAPI::Resource
   abstract
@@ -1894,6 +1944,35 @@ class RespondentResource < JSONAPI::Resource
   abstract
 end
 
+class StorageResource < JSONAPI::Resource
+  key_type :string
+  primary_key :token
+
+  attribute :name
+end
+
+class KeeperResource < JSONAPI::Resource
+  has_one :keepable, polymorphic: true, foreign_key: :keepable_id
+
+  attribute :name
+end
+
+class KeepableResource < JSONAPI::Resource
+end
+
+class AccessCardResource < JSONAPI::Resource
+  key_type :string
+  primary_key :token
+
+  attribute :security_level
+end
+
+class WorkerResource < JSONAPI::Resource
+  has_one :access_card
+
+  attribute :name
+end
+
 ### PORO Data - don't do this in a production app
 $breed_data = BreedData.new
 $breed_data.add(Breed.new(0, 'persian'))

test/fixtures/keepers.yml

@@ -0,0 +1,5 @@
+john_doe:
+  id: 1
+  name: "John Doe"
+  keepable_id: 1 # storages.yml warehouse_1
+  keepable_type: "Storage"

test/fixtures/storages.yml

@@ -0,0 +1,4 @@
+warehouse_1:
+  id: 1
+  name: "Warehouse 1"
+  token: "some-token"

test/fixtures/workers.yml

@@ -0,0 +1,4 @@
+john_doe_worker:
+  id: 1
+  name: "John Doe"
+  access_card_id: 1 # access_cards.yml john_doe_worker_card

test/integration/requests/request_test.rb

@@ -1102,4 +1102,48 @@ def test_getting_resource_with_correct_type_when_sti
     assert_cacheable_jsonapi_get '/vehicles/1'
     assert_equal 'cars', json_response['data']['type']
   end
+
+  def test_get_resource_with_polymorphic_relationship_and_changed_primary_key
+    keeper = Keeper.find(1)
+    storage = keeper.keepable
+    assert_cacheable_jsonapi_get '/keepers/1?include=keepable'
+    assert_jsonapi_response 200
+
+    data = json_response['data']
+    refute_nil data
+    assert_equal keeper.id.to_s, data['id']
+
+    refute_nil data['relationships']
+    refute_nil data['relationships']['keepable']
+    refute_nil data['relationships']['keepable']['data']
+    assert_equal 'storages', data['relationships']['keepable']['data']['type']
+    assert_equal storage.token, data['relationships']['keepable']['data']['id']
+
+    included = json_response['included']
+    refute_nil included
+    assert_equal 'storages', included.first['type']
+    assert_equal storage.token, included.first['id']
+  end
+
+  def test_get_resource_with_belongs_to_relationship_and_changed_primary_key
+    worker = Worker.find(1)
+    access_card = worker.access_card
+    assert_cacheable_jsonapi_get '/workers/1?include=access_card'
+    assert_jsonapi_response 200
+
+    data = json_response['data']
+    refute_nil data
+    assert_equal worker.id.to_s, data['id']
+
+    refute_nil data['relationships']
+    refute_nil data['relationships']['access_card']
+    refute_nil data['relationships']['access_card']['data']
+    assert_equal 'access_cards', data['relationships']['access_card']['data']['type']
+    assert_equal access_card.token, data['relationships']['access_card']['data']['id']
+
+    included = json_response['included']
+    refute_nil included
+    assert_equal 'access_cards', included.first['type']
+    assert_equal access_card.token, included.first['id']
+  end
 end

test/test_helper.rb

@@ -377,6 +377,9 @@ class CatResource < JSONAPI::Resource
     end
   end
 
+  jsonapi_resources :keepers, only: [:show]
+  jsonapi_resources :workers, only: [:show]
+
   mount MyEngine::Engine => "/boomshaka", as: :my_engine
   mount ApiV2Engine::Engine => "/api_v2", as: :api_v2_engine
 end