Added code to error attributes. Closes #95

Author: stas

lib/jsonapi/error_serializer.rb

@@ -8,7 +8,7 @@ class ErrorSerializer
     set_type :error
 
     # Object/Hash attribute helpers.
-    [:status, :source, :title, :detail].each do |attr_name|
+    [:status, :source, :title, :detail, :code].each do |attr_name|
       attribute attr_name do |object|
         object.try(attr_name) || object.try(:fetch, attr_name, nil)
       end

spec/errors_spec.rb

@@ -32,11 +32,16 @@
       it do
         expect(response).to have_http_status(:unprocessable_entity)
         expect(response_json['errors'].size).to eq(1)
+
+        expect(response_json['errors'].first.keys)
+          .to contain_exactly('status', 'source', 'title', 'detail', 'code')
+
         expect(response_json['errors'][0]['status']).to eq('422')
         expect(response_json['errors'][0]['title'])
           .to eq(Rack::Utils::HTTP_STATUS_CODES[422])
         expect(response_json['errors'][0]['source']).to eq('pointer' => '')
         expect(response_json['errors'][0]['detail']).to be_nil
+        expect(response_json['errors'][0]['code']).to be_nil
       end
     end