new file for various utilities

Author: vkuznet

utils.go

@@ -0,0 +1,30 @@
+package main
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"strings"
+)
+
+func getIP(r *http.Request) string {
+	// Check if the request was forwarded by a proxy (e.g. X-Forwarded-For header)
+	// This is useful when behind a load balancer or reverse proxy
+	ip := r.Header.Get("X-Forwarded-For")
+	if ip == "" {
+		ip = r.Header.Get("X-Real-Ip")
+	}
+	if ip != "" {
+		// In case of multiple IPs in the X-Forwarded-For header, take the first one
+		ips := strings.Split(ip, ",")
+		return strings.TrimSpace(ips[0])
+	}
+
+	// Otherwise, extract the IP from RemoteAddr
+	ip, _, err := net.SplitHostPort(r.RemoteAddr)
+	if err != nil {
+		fmt.Println("Error parsing RemoteAddr:", err)
+		return ""
+	}
+	return ip
+}