# File lib/mcollective/rpc/client.rb, line 696
      def load_aggregate_functions(action, ddl)
        return nil unless ddl
        return nil unless ddl.action_interface(action).keys.include?(:aggregate)

        return Aggregate.new(ddl.action_interface(action))

      rescue => e
        Log.error("Failed to load aggregate functions, calculating summaries disabled: %s: %s (%s)" % [e.backtrace.first, e.to_s, e.class])
        return nil
      end