Since we liked to access ipify's API for a small project, we developed the following library.
go get github.com/jjideenschmiede/goipify
With this function you get your current public IP address. You get the data back in JSON format. And you can access it directly via the Struct.
// Get my ip address
ip, err := goipify.Ip()
if err != nil {
log.Fatalln(err)
} else {
log.Println(ip)
}