code: func NewEndpoint(serviceName string, hostPort string) (*model.Endpoint, error) {
  	e := &model.Endpoint{
  		ServiceName: serviceName,
  	}
  
  	if hostPort == "" || hostPort == ":0" {
  		if serviceName == "" {
  			// if all properties are empty we should not have an Endpoint object.
  			return nil, nil
  		}
  		return e, nil
  	}
  
  	if strings.IndexByte(hostPort, ':') < 0 {
  		hostPort += ":0"
  	}
  
  	host, port, err := net.SplitHostPort(hostPort)
  	if err != nil {
  		return nil, err
  	}
  
  	p, err := strconv.ParseUint(port, 10, 16)
  	if err != nil {
  		return nil, err
  	}
  	e.Port = uint16(p)
  
  	addrs, err := net.LookupIP(host)
  	if err != nil {
  		return nil, err
  	}
  
  	for i := range addrs {
  		addr := addrs[i].To4()
  		if addr == nil {
  			// IPv6 - 16 bytes
  			if e.IPv6 == nil {
  				e.IPv6 = addrs[i].To16()
  			}
  		} else {
  			// IPv4 - 4 bytes
  			if e.IPv4 == nil {
  				e.IPv4 = addr
  			}
  		}
  		if e.IPv4 != nil && e.IPv6 != nil {
  			// Both IPv4 & IPv6 have been set, done...
  			break
  		}
  	}
  
  	return e, nil
  }
docs: // NewEndpoint creates a new endpoint given the provided serviceName and
  // hostPort.