code: func (c *Collector) pollHost() {
  	now := time.Now().UTC()
  	c.timestamp = now.Unix()
  
  	// Fetch node-level metrics for all DC/OS roles
  	c.log.Debugf("Fetching node-level metrics from DC/OS host %s", c.nodeInfo.Hostname)
  	nm, err := getNodeMetrics()
  	if err != nil {
  		c.log.Errorf("Failed to get node-level metrics. %s", err)
  	} else {
  		c.nodeMetrics = nm
  	}
  
  	c.log.Infof("Finished polling DC/OS host %s, took %f seconds.", c.nodeInfo.Hostname, time.Since(now).Seconds())
  }
docs: // pollHost queries the DC/OS hsot for metrics and returns.