Fix deserialization.

lib/jsonapi/rails/action_controller.rb

@@ -7,54 +7,63 @@ module ActionController
       def self.included(base)
         base.class_eval do
           extend ClassMethods
-          prepend InstanceMethods
         end
       end
 
       module ClassMethods
-        def deserializable_resource(key, klass = nil, &block)
+        def deserializable_resource(key, *args, &block)
+          klass = args.shift unless args.first.is_a?(Hash)
+          options = args.first || {}
           if klass.nil?
             klass = Class.new(JSONAPI::Deserializable::Resource, &block)
           end
-          @deserializable_key = key
-          @deserializable_class = klass
-          @deserializable_parser = JSONAPI::Parser::Resource
+          use DeserializeResource, key, klass, options
         end
 
-        def deserializable_relationship(key, klass = nil, &block)
+        def deserializable_relationship(key, *args, &block)
+          klass = args.shift unless args.first.is_a?(Hash)
+          options = args.first || {}
           if klass.nil?
             klass = Class.new(JSONAPI::Deserializable::Relationship, &block)
           end
+          use DeserializeResource, key, klass, options
+        end
+      end
+
+      class DeserializationMiddleware
+        JSONAPI_KEYS = %w(data meta links jsonapi).freeze
+        def initialize(app, key, klass)
+          @app = app
           @deserializable_key = key
           @deserializable_class = klass
-          @deserializable_parser = JSONAPI::Parser::Relationship
         end
 
-        def deserializable_class
-          @deserializable_class
-        end
+        def call(env)
+          request = Rack::Request.new(env)
+          body = request.params.slice(*JSONAPI_KEYS)
+          parser.parse!(body)
+          deserialized_hash = @deserializable_class.call(body)
+          jsonapi = {}
+          JSONAPI_KEYS.each do |key|
+            next unless request.params.key?(key)
+            jsonapi[key.to_sym] = request.delete_param(key)
+          end
+          request.update_param(:_jsonapi, jsonapi)
+          request.update_param(@deserializable_key, deserialized_hash)
 
-        def deserializable_key
-          @deserializable_key
+          @app.call(env)
         end
+      end
 
-        def deserializable_parser
-          @deserializable_parser
+      class DeserializeResource < DeserializationMiddleware
+        def parser
+          JSONAPI::Parser::Resource
         end
       end
 
-      module InstanceMethods
-        def params
-          params = super
-          key = self.class.deserializable_key
-          return params if body.key?(key)
-          parser = self.class.deserializable_parser
-          return params unless parser
-
-          parser.parse!(body)
-          deserializable_class = self.class.deserializable_class
-
-          params.merge!(key => deserializable_class.call(params))
+      class DeserializeRelationship < DeserializationMiddleware
+        def parser
+          JSONAPI::Parser::Relationship
         end
       end
     end

lib/jsonapi/rails/railtie.rb

@@ -39,5 +39,6 @@ class Railtie < ::Rails::Railtie
 end
 
 ActiveSupport.on_load(:action_controller) do
+  require 'jsonapi/rails/action_controller'
   include JSONAPI::Rails::ActionController
 end