add GetIP func

Author: adelowo

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2024 Ayinke Ventures
+Copyright (c) 2025 Ayinke Ventures
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

ip.go

@@ -0,0 +1,41 @@
+package hermes
+
+import (
+	"net"
+	"net/http"
+	"strings"
+)
+
+var (
+	xForwardedFor = http.CanonicalHeaderKey("X-Forwarded-For")
+	xRealIP       = http.CanonicalHeaderKey("X-Real-IP")
+)
+
+func GetIP(r *http.Request) net.IP {
+	// cloudflare always prioritized
+	cloudflareIP := r.Header.Get("CF-Connecting-IP")
+	if cloudflareIP != "" {
+		return net.ParseIP(cloudflareIP)
+	}
+
+	if xff := r.Header.Get(xForwardedFor); xff != "" {
+		i := strings.Index(xff, ", ")
+
+		if i == -1 {
+			i = len(xff)
+		}
+
+		return net.ParseIP(xff[:i])
+	}
+
+	if ip := r.Header.Get(xRealIP); ip != "" {
+		return net.ParseIP(ip)
+	}
+
+	h, _, err := net.SplitHostPort(r.RemoteAddr)
+	if err != nil {
+		return net.IP{}
+	}
+
+	return net.ParseIP(h)
+}