Cache render JSON in a Rails controller

models_controller.rb

  def show
    if stale?(@model, public: true)
      respond_to do |format|
        format.json do
          full_structure_json = Rails.cache.fetch("#{@model.cache_key}") do
            MyCustomSerializer.new(@model).to_json
          end

          render json: full_structure_json
        end
      end
    end
  end

This solution works. Is there a better way of doing this?