middleware (ActiveSupport::Cache::Strategy::LocalCache)

    # File lib/active_support/cache/strategy/local_cache.rb, line 15
            def middleware
              @middleware ||= begin
                klass = Class.new
                klass.class_eval("def initialize(app)\n@app = app\nend\n\ndef call(env)\nThread.current[:\#{thread_local_key}] = MemoryStore.new\n@app.call(env)\nensure\nThread.current[:\#{thread_local_key}] = nil\nend\n", __FILE__, __LINE__)
                klass
              end
            end