Merge pull request #130 from yellowspot/fix-rails-deprecation-warning

Fix rails 6.1 deprecation warning on ActiveModel::Errors#keys (Backward compatible)

Author: dawidof

Diff for: VERSION

@@ -1 +1 @@
-0.4.0
+0.4.1

Diff for: jsonapi-rails.gemspec

@@ -18,7 +18,7 @@ Gem::Specification.new do |spec|
   spec.add_dependency 'jsonapi-parser', '~> 0.1.0'
 
   spec.add_development_dependency 'rails', '~> 5.0'
-  spec.add_development_dependency 'sqlite3', '~> 1.3.6'
+  spec.add_development_dependency 'sqlite3', '~> 1.3'
   spec.add_development_dependency 'rake',        '~> 11.3'
   spec.add_development_dependency 'rspec-rails', '~> 3.5'
   spec.add_development_dependency 'with_model',  '~> 2.0'

Diff for: lib/jsonapi/rails/serializable_active_model_errors.rb

@@ -25,14 +25,20 @@ def initialize(exposures)
       end
 
       def as_jsonapi
-        @errors.keys.flat_map do |key|
+        error_keys.flat_map do |key|
           @errors.full_messages_for(key).map do |message|
             SerializableActiveModelError.new(field: key, message: message,
                                              pointer: @reverse_mapping[key])
               .as_jsonapi
           end
         end
       end
+
+      private
+
+      def error_keys
+        @errors.respond_to?(:attribute_names) ? @errors.attribute_names : @errors.keys
+      end
     end
   end
 end