From 45ca65110efcff2b0ce675741632530105c78337 Mon Sep 17 00:00:00 2001
From: Ben Sarmiento <ben.sarmiento@forto.com>
Date: Fri, 1 Dec 2023 13:29:59 +0100
Subject: [PATCH] Fix ipv6 client

---
 pkg/http/client.go | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/pkg/http/client.go b/pkg/http/client.go
index 4fd9d37..6c14575 100644
--- a/pkg/http/client.go
+++ b/pkg/http/client.go
@@ -24,7 +24,7 @@ type HTTPClient struct {
 	getRetryIncr func(resp *http.Response, err error) int
 	bearerToken  string
 	cfg          config.ConfigInterface
-	ipv6         cmap.ConcurrentMap[string, net.IP]
+	ipv6         cmap.ConcurrentMap[string, string]
 	log          *zap.SugaredLogger
 }
 
@@ -60,26 +60,32 @@ func NewHTTPClient(token string, maxRetries int, timeoutSecs int, cfg config.Con
 			return RATE_LIMIT_FACTOR // retry and increment attempt
 		},
 		cfg:  cfg,
-		ipv6: cmap.New[net.IP](),
+		ipv6: cmap.New[string](),
 		log:  log,
 	}
 
 	if cfg.ShouldForceIPv6() {
 		dialer := &net.Dialer{}
-
 		dialContext := func(ctx context.Context, network, address string) (net.Conn, error) {
-			ips, err := net.DefaultResolver.LookupIPAddr(ctx, address)
+			host, port, _ := net.SplitHostPort(address)
+			if ipv6Address, ok := client.ipv6.Get(address); ok {
+				return dialer.DialContext(ctx, network, ipv6Address)
+			}
+
+			ips, err := net.DefaultResolver.LookupIPAddr(ctx, host)
 			if err != nil {
 				return nil, err
 			}
 
 			for _, ip := range ips {
 				if ip.IP.To4() == nil { // IPv6 address found
-					ipv6Address := "[" + ip.IP.String() + "]"
+					ip6Host := ip.IP.String()
+					ipv6Address := net.JoinHostPort(ip6Host, port)
+					client.ipv6.Set(address, ipv6Address)
 					return dialer.DialContext(ctx, network, ipv6Address)
 				}
 			}
-			return nil, net.UnknownNetworkError("no IPv6 address found")
+			return dialer.DialContext(ctx, network, address)
 		}
 
 		transport := &http.Transport{