From 3748bbfaa3bd49883436203d6099c7035494aba9 Mon Sep 17 00:00:00 2001
From: Mike Rheinheimer <mrheinheimer@atlassian.com>
Date: Tue, 12 Jul 2022 15:45:42 -0500
Subject: [PATCH] protect the cache from DNS responses that lack an Answer, add
 .gitignore to ignore vendor/ folder

---
 .gitignore           | 1 +
 fastdialer/dialer.go | 6 ++++--
 2 files changed, 5 insertions(+), 2 deletions(-)
 create mode 100644 .gitignore

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..48b8bf9
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+vendor/
diff --git a/fastdialer/dialer.go b/fastdialer/dialer.go
index 8c90672..2cfeb16 100644
--- a/fastdialer/dialer.go
+++ b/fastdialer/dialer.go
@@ -370,8 +370,10 @@ func (d *Dialer) GetDNSData(hostname string) (*retryabledns.DNSData, error) {
 		if data == nil {
 			return nil, ResolveHostError
 		}
-		b, _ := data.Marshal()
-		err = d.hm.Set(hostname, b)
+		if len(data.A)+len(data.AAAA) > 0 {
+			b, _ := data.Marshal()
+			err = d.hm.Set(hostname, b)
+		}
 		if err != nil {
 			return nil, err
 		}