How do I get the local IP address in Go?

Question

I want to get the computer\'s IP address. I used the code below, but it returns 127.0.0.1.

I want to get the IP address, such as 10.32.10.111

Answer 1

func resolveHostIp() (string) {

    netInterfaceAddresses, err := net.InterfaceAddrs()

    if err != nil { return "" }

    for _, netInterfaceAddress := range netInterfaceAddresses {

        networkIp, ok := netInterfaceAddress.(*net.IPNet)

        if ok && !networkIp.IP.IsLoopback() && networkIp.IP.To4() != nil {

            ip := networkIp.IP.String()

            fmt.Println("Resolved Host IP: " + ip)

            return ip
        }
    }
    return ""
}

Answer 2

Here is a better solution to retrieve the preferred outbound ip address when there are multiple ip interfaces exist on the machine.

import (
    "log"
    "net"
    "strings"
)

// Get preferred outbound ip of this machine
func GetOutboundIP() net.IP {
    conn, err := net.Dial("udp", "8.8.8.8:80")
    if err != nil {
        log.Fatal(err)
    }
    defer conn.Close()

    localAddr := conn.LocalAddr().(*net.UDPAddr)

    return localAddr.IP
}