module ActiveModel::Serializer::Caching::ClassMethods

def cache_read_multi(collection_serializer, adapter_instance, include_directive)
  return {} if ActiveModelSerializers.config.cache_store.blank?
  keys = object_cache_keys(collection_serializer, adapter_instance, include_directive)
  return {} if keys.blank?
  ActiveModelSerializers.config.cache_store.read_multi(*keys)
end