1. // 获取IP地址
    2. func GetIP(r *http.Request) string {
    3.     remoteIP := r.RemoteAddr
    5.     // 处理 X-Real-IP 头
    6.     if ip := r.Header.Get("X-Real-IP"); ip != "" {
    7.         remoteIP = ip
    8.     }
    10.     // 处理 X-Forwarded-For 头，如果有多个IP，取第一个
    11.     if ips := r.Header.Get("X-Forwarded-For"); ips != "" {
    12.         if ip := strings.TrimSpace(strings.Split(ips, ",")[0]); ip != "" {
    13.             remoteIP = ip
    14.         }
    15.     }
    17.     // 如果 remoteIP 是一个本地地址，则返回第一个 non-local IP
    18.     if IsLocalhost(remoteIP) {
    19.         ips := GetNonLocalIPs(r)
    20.         if len(ips) > 0 {
    21.             remoteIP = ips[0]
    22.         }
    23.     }
    25.     return remoteIP
    26. }
    28. // 判断一个 IP 是否为本地地址
    29. func IsLocalhost(ip string) bool {
    30.     ip = strings.TrimSpace(ip)
    31.     return ip == "127.0.0.1" || ip == "::1" || strings.HasPrefix(ip, "192.168.") || strings.HasPrefix(ip, "10.") || strings.HasPrefix(ip, "172.16.")
    32. }
    34. // 获取 request 中非本地地址的 IP 列表
    35. func GetNonLocalIPs(r *http.Request) []string {
    36.     ips := []string{}
    37.     forwardedFors := r.Header.Get("X-Forwarded-For")
    38.     if forwardedFors != "" {
    39.         for _, forwardedFor := range strings.Split(forwardedFors, ",") {
    40.             ip := strings.TrimSpace(forwardedFor)
    41.             if !IsLocalhost(ip) {
    42.                 ips = append(ips, ip)
    43.             }
    44.         }
    45.     }
    46.     if len(ips) == 0 {
    47.         // 获取 RemoteAddr 的 non-local IP
    48.         ip, _, err := net.SplitHostPort(r.RemoteAddr)
    49.         if err == nil && !IsLocalhost(ip) {
    50.             ips = append(ips, ip)
    51.         }
    52.     }
    53.     return ips
    54. }