module ActionView module CollectionCaching # :nodoc: extend ActiveSupport::Concern included do # Fallback cache store if Action View is used without Rails. # Otherwise overridden in Railtie to use Rails.cache. mattr_accessor(:collection_cache) { ActiveSupport::Cache::MemoryStore.new } end private def cache_collection_render(instrumentation_payload) return yield unless @options[:cached] keyed_collection = collection_by_cache_keys cached_partials = collection_cache.read_multi(*keyed_collection.keys) instrumentation_payload[:cache_hits] = cached_partials.size @collection = keyed_collection.reject { |key, _| cached_partials.key?(key) }.values rendered_partials = @collection.empty? ? [] : yield index = 0 fetch_or_cache_partial(cached_partials, order_by: keyed_collection.each_key) do rendered_partials[index].tap { index += 1 } end end def collection_by_cache_keys @collection.each_with_object({}) do |item, hash| hash[expanded_cache_key(item)] = item end end def expanded_cache_key(key) key = @view.fragment_cache_key(@view.cache_fragment_name(key, virtual_path: @template.virtual_path)) key.frozen? ? key.dup : key # #read_multi & #write may require mutability, Dalli 2.6.0. end def fetch_or_cache_partial(cached_partials, order_by:) order_by.map do |cache_key| cached_partials.fetch(cache_key) do yield.tap do |rendered_partial| collection_cache.write(cache_key, rendered_partial) end end end end end end