From e4ee7928f9d804a13e9b1f532f79cd0ab3624418 Mon Sep 17 00:00:00 2001
From: Johnny Walker <jwalker@designsforhealth.com>
Date: Sat, 11 Apr 2026 16:40:45 -0400
Subject: [PATCH] fix: wrap host with brackets if IPv6 address detected

---
 kubernetes-client/src/Kubernetes/Client/Config.hs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/kubernetes-client/src/Kubernetes/Client/Config.hs b/kubernetes-client/src/Kubernetes/Client/Config.hs
index beafe692..3de2e95b 100644
--- a/kubernetes-client/src/Kubernetes/Client/Config.hs
+++ b/kubernetes-client/src/Kubernetes/Client/Config.hs
@@ -96,10 +96,17 @@ mkInClusterClientConfig = do
     defTlsParams
   host <- liftIO $ getEnv "KUBERNETES_SERVICE_HOST"
   port <- liftIO $ getEnv "KUBERNETES_SERVICE_PORT"
-  cfg  <- setMasterURI (T.pack $ "https://" ++ host ++ ":" ++ port) <$> liftIO
+  cfg  <- setMasterURI (T.pack $ "https://" ++ (formatHost host) ++ ":" ++ port) <$> liftIO
     (K.newConfig >>= setTokenFileAuth (serviceAccountDir ++ "/token"))
   return (mgr, cfg)
 
+-- | Wraps host with brackets if IPv6 address detected and not already wrapped
+formatHost :: String -> String
+formatHost host@('[' : _) = host -- already wrapped with brackets
+formatHost host
+  | ':' `elem` host = "[" ++ host ++ "]" -- assume IPv6 if host has colons
+  | otherwise = host
+
 -- |Sets the master URI in the 'K.KubernetesClientConfig'.
 setMasterURI
   :: T.Text                -- ^ Master URI