Public IP - Using Go "net" package

ip.go

package main

import (
	"context"
	"fmt"
	"log"
	"net"
)

func main() {

	resolver := net.Resolver{
		PreferGo: true,
		Dial: func(ctx context.Context, network, address string) (net.Conn, error) {
			d := net.Dialer{}
			return d.DialContext(ctx, "udp", "resolver1.opendns.com:53")
		},
	}

	ips, err := resolver.LookupHost(context.Background(), "myip.opendns.com")
	if err != nil {
		log.Fatal(err)
	}

	for _, ip := range ips {
		fmt.Println(ip)
	}

}