Add jsonapi_pointers method to ActionController.

Author: Michael Deutsch

lib/jsonapi/rails/action_controller.rb

@@ -4,6 +4,8 @@
 module JSONAPI
   module Rails
     module ActionController
+      extend ActiveSupport::Concern
+
       REVERSE_MAPPING_KEY = 'jsonapi_deserializable.reverse_mapping'.freeze
 
       module ClassMethods
@@ -30,6 +32,12 @@ def _deserializable(key, options, fallback, &block)
           end
         end
       end
+
+      private
+
+      def jsonapi_pointers
+        request.env[REVERSE_MAPPING_KEY]
+      end
     end
   end
 end

lib/jsonapi/rails/railtie.rb

@@ -17,7 +17,7 @@ class Railtie < ::Rails::Railtie
       initializer 'jsonapi-rails.action_controller' do
         ActiveSupport.on_load(:action_controller) do
           require 'jsonapi/rails/action_controller'
-          extend ::JSONAPI::Rails::ActionController::ClassMethods
+          include ::JSONAPI::Rails::ActionController
 
           Mime::Type.register MEDIA_TYPE, :jsonapi
 
@@ -35,9 +35,8 @@ class Railtie < ::Rails::Railtie
 
           ::ActionController::Renderers.add(:jsonapi_error) do |errors, options|
             # Renderer proc is evaluated in the controller context, so it
-            # has access to the request object.
-            reverse_mapping = request.env[ActionController::REVERSE_MAPPING_KEY]
-            options = options.merge(_reverse_mapping: reverse_mapping)
+            # has access to the jsonapi_pointers method.
+            options = options.merge(_jsonapi_pointers: jsonapi_pointers)
             self.content_type ||= Mime[:jsonapi]
 
             RENDERERS[:jsonapi_error].render(errors, options).to_json

spec/action_controller_spec.rb

@@ -0,0 +1,19 @@
+require 'rails_helper'
+
+RSpec.describe JSONAPI::Rails::ActionController do
+  class TestController < ActionController::Base
+    deserializable_resource "things"
+  end
+
+  let(:controller) { TestController.new }
+
+  context 'source pointers' do
+    it 'should fetch the mapping created during deserialization' do
+      reverse_mapping = {id: "/data/id", type: "/data/type"}
+      allow(controller).to receive(:request) do
+        OpenStruct.new(env: {'jsonapi_deserializable.reverse_mapping' => reverse_mapping})
+      end
+      expect(controller.send(:jsonapi_pointers)).to equal reverse_mapping
+    end
+  end
+end