code: func (c *Collector) transform() (out []producers.MetricsMessage) {
  	var msg producers.MetricsMessage
  	t := time.Unix(c.timestamp, 0)
  
  	// Produce node metrics
  	msg = producers.MetricsMessage{
  		Name:       producers.NodeMetricPrefix,
  		Datapoints: c.nodeMetrics,
  		Dimensions: producers.Dimensions{
  			MesosID:   c.nodeInfo.MesosID,
  			ClusterID: c.nodeInfo.ClusterID,
  			Hostname:  c.nodeInfo.Hostname,
  		},
  		Timestamp: t.UTC().Unix(),
  	}
  	out = append(out, msg)
  
  	return out
  }
docs: // transform will take metrics retrieved from the agent and perform any
  // transformations necessary to make the data fit the output expected by
  // producers.MetricsMessage.