code: func (t *Task) PopulateProto(d *pb.MetricsCollection) {
  	d.TargetSchema = &pb.MetricsCollection_Task{
  		&pb.Task{
  			ServiceName: &t.ServiceName,
  			JobName:     &t.JobName,
  			DataCenter:  &t.DataCenter,
  			HostName:    &t.HostName,
  			TaskNum:     &t.TaskNum,
  		},
  	}
  }
docs: // PopulateProto implements Target.