Golang gin 仅在 ipv4 中获取客户端 IP

Question

I'm trying to get the IP address of the client when using gin-gonic but sometimes it gives me the IPv6 address which I don't want.

My current code looks like this:

web.POST("/path", func(c *gin.Context) {
    ipAddr := c.ClientIP() // sometimes ipv4, sometimes ipv6

How do I get only the IPv4 address?

For reference I'm only listening on IPv4 address:

server := &http.Server{
    Handler: router,
}
l, err := net.Listen("tcp4", cfg.Listen)
if err != nil {
    panic(err)
}
err = server.Serve(l)

---

Here are examples of the IPv6 addresses I'm receiving:

2402:800:6371:2f72:xxxx:bf67:3689:95df
2001:44b8:2169:c800:xxxx:c80a:b134:cc40

Answer 1

Not sure if this helps, but this below function helped me to get the IPAddress

func getClientIPByHeaders(req *http.Request) (ip string, err error) {

    // Client could be behid a Proxy, so Try Request Headers (X-Forwarder)
    ipSlice := []string{}

    ipSlice = append(ipSlice, req.Header.Get("X-Forwarded-For"))
    ipSlice = append(ipSlice, req.Header.Get("x-forwarded-for"))
    ipSlice = append(ipSlice, req.Header.Get("X-FORWARDED-FOR"))

    for _, v := range ipSlice {
        log.Printf("debug: client request header check gives ip: %v", v)
        if v != "" {
            return v, nil
        }
    }
    err = errors.New("error: Could not find clients IP address from the Request Headers")
    return "", err

}