Move attributes cache method out of concern

Author: bf4

lib/active_model/serializer.rb

@@ -379,8 +379,7 @@ def associations(include_directive = ActiveModelSerializers.default_include_dire
     def serializable_hash(adapter_options = nil, options = {}, adapter_instance = self.class.serialization_adapter_instance)
       adapter_options ||= {}
       options[:include_directive] ||= ActiveModel::Serializer.include_directive_from_options(adapter_options)
-      cached_attributes = adapter_options[:cached_attributes] ||= {}
-      resource = fetch_attributes(options[:fields], cached_attributes, adapter_instance)
+      resource = attributes_hash(adapter_options, options, adapter_instance)
       relationships = resource_relationships(adapter_options, options, adapter_instance)
       resource.merge(relationships)
     end
@@ -412,6 +411,17 @@ def read_attribute_for_serialization(attr)
       end
     end
 
+    # @api private
+    def attributes_hash(_adapter_options, options, adapter_instance)
+      if self.class.cache_enabled?
+        fetch_attributes(options[:fields], options[:cached_attributes] || {}, adapter_instance)
+      elsif self.class.fragment_cache_enabled?
+        fetch_attributes_fragment(adapter_instance, options[:cached_attributes] || {})
+      else
+        attributes(options[:fields], true)
+      end
+    end
+
     # @api private
     def resource_relationships(adapter_options, options, adapter_instance)
       relationships = {}

lib/active_model/serializer/concerns/caching.rb

@@ -170,6 +170,7 @@ def fragment_cache_enabled?
 
         # Read cache from cache_store
         # @return [Hash]
+        # Used in CollectionSerializer to set :cached_attributes
         def cache_read_multi(collection_serializer, adapter_instance, include_directive)
           return {} if ActiveModelSerializers.config.cache_store.blank?
 
@@ -215,23 +216,17 @@ def object_cache_key(serializer, adapter_instance)
 
       ### INSTANCE METHODS
       def fetch_attributes(fields, cached_attributes, adapter_instance)
-        if serializer_class.cache_enabled?
-          key = cache_key(adapter_instance)
-          cached_attributes.fetch(key) do
-            serializer_class.cache_store.fetch(key, serializer_class._cache_options) do
-              attributes(fields, true)
-            end
+        key = cache_key(adapter_instance)
+        cached_attributes.fetch(key) do
+          fetch(adapter_instance, serializer_class._cache_options, key) do
+            attributes(fields, true)
           end
-        elsif serializer_class.fragment_cache_enabled?
-          fetch_attributes_fragment(adapter_instance, cached_attributes)
-        else
-          attributes(fields, true)
         end
       end
 
-      def fetch(adapter_instance, cache_options = serializer_class._cache_options)
+      def fetch(adapter_instance, cache_options = serializer_class._cache_options, key = cache_key(adapter_instance))
         if serializer_class.cache_store
-          serializer_class.cache_store.fetch(cache_key(adapter_instance), cache_options) do
+          serializer_class.cache_store.fetch(key, cache_options) do
             yield
           end
         else
@@ -242,7 +237,6 @@ def fetch(adapter_instance, cache_options = serializer_class._cache_options)
       # 1. Determine cached fields from serializer class options
       # 2. Get non_cached_fields and fetch cache_fields
       # 3. Merge the two hashes using adapter_instance#fragment_cache
-      # rubocop:disable Metrics/AbcSize
       def fetch_attributes_fragment(adapter_instance, cached_attributes = {})
         serializer_class._cache_options ||= {}
         serializer_class._cache_options[:key] = serializer_class._cache_key if serializer_class._cache_key
@@ -257,7 +251,7 @@ def fetch_attributes_fragment(adapter_instance, cached_attributes = {})
         key = cache_key(adapter_instance)
         cached_hash =
           cached_attributes.fetch(key) do
-            serializer_class.cache_store.fetch(key, serializer_class._cache_options) do
+            fetch(adapter_instance, serializer_class._cache_options, key) do
               hash = attributes(cached_fields, true)
               include_directive = JSONAPI::IncludeDirective.new(cached_fields - hash.keys)
               hash.merge! resource_relationships({}, { include_directive: include_directive }, adapter_instance)
@@ -266,7 +260,6 @@ def fetch_attributes_fragment(adapter_instance, cached_attributes = {})
         # Merge both results
         adapter_instance.fragment_cache(cached_hash, non_cached_hash)
       end
-      # rubocop:enable Metrics/AbcSize
 
       def cache_key(adapter_instance)
         return @cache_key if defined?(@cache_key)