Refactor

ip/interface.go

@@ -0,0 +1,46 @@
+package ip
+
+import (
+	"errors"
+	"net"
+)
+
+func GetInterfaceIP(iface_name string) (net.IP, error) {
+	ip := net.IP{}
+	iface, err := net.InterfaceByName(iface_name)
+	if err != nil {
+		return ip, err
+	}
+
+	addrs, err := iface.Addrs()
+	if err != nil {
+		return ip, err
+	}
+
+	return GetPublicIp(addrs)
+}
+
+func GetPublicIp(list []net.Addr) (net.IP, error) {
+	for _, addr := range list {
+		ip, err := AddrToIP(addr)
+		if err == nil && !ip.IsPrivate() {
+			return ip, nil
+		}
+	}
+
+	return nil, errors.New("no public ip found on interface")
+}
+
+func AddrToIP(addr net.Addr) (net.IP, error) {
+	switch v := addr.(type) {
+	case *net.IPNet:
+		return v.IP, nil
+	case *net.IPAddr:
+		return v.IP, nil
+	case *net.UDPAddr:
+		return v.IP, nil
+	case *net.TCPAddr:
+		return v.IP, nil
+	}
+	return nil, errors.New("could not find ip")
+}