def duplicate?(request, method, idempotent)
      if !idempotent && @dispatched_cache
        if (serviced_by = @dispatched_cache.serviced_by(request.token))
          from_retry = ""
        else
          from_retry = "retry "
          request.tries.each { |t| break if (serviced_by = @dispatched_cache.serviced_by(t)) }
        end
        if serviced_by
          @reject_stats.update("#{from_retry}duplicate (#{method})")
          msg = "<#{request.token}> already serviced by #{serviced_by == @identity ? 'self' : serviced_by}"
          Log.info("REJECT #{from_retry.upcase}DUP #{msg}")
          msg
        end
      end
    end
def duplicate?(request, method, idempotent)
      if !idempotent && @dispatched_cache
        if (serviced_by = @dispatched_cache.serviced_by(request.token))
          from_retry = ""
        else
          from_retry = "retry "
          request.tries.each { |t| break if (serviced_by = @dispatched_cache.serviced_by(t)) }
        end
        if serviced_by
          @reject_stats.update("#{from_retry}duplicate (#{method})")
          msg = "<#{request.token}> already serviced by #{serviced_by == @identity ? 'self' : serviced_by}"
          Log.info("REJECT #{from_retry.upcase}DUP #{msg}")
          msg
        end
      end
    end
Determine whether this request is a duplicate

 === Parameters
 request(Request|Push):: Packet containing request
 method(String):: Actor method requested to be performed
 idempotent(Boolean):: Whether this method is idempotent

 === Return
 (String|nil):: Messaging describing who already serviced request if it is a duplicate, otherwise nil