From dd281fa6259f2f44bd5dfc1356afeb821675cf1e Mon Sep 17 00:00:00 2001
From: "Mads R. Havmand" <mads@v42.dk>
Date: Sat, 9 Dec 2023 12:08:39 +0100
Subject: [PATCH] force lowercase when checking header

---
 interceptors/realip/realip.go | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/interceptors/realip/realip.go b/interceptors/realip/realip.go
index bc9350964..8d5a0214e 100644
--- a/interceptors/realip/realip.go
+++ b/interceptors/realip/realip.go
@@ -58,11 +58,11 @@ func getHeader(ctx context.Context, key string) string {
 		return ""
 	}
 
-	if md[key] == nil {
+	if md[strings.ToLower(key)] == nil {
 		return ""
 	}
 
-	return md[key][0]
+	return md[strings.ToLower(key)][0]
 }
 
 func ipFromHeaders(ctx context.Context, headers []string) netip.Addr {