commit 590fd1b7ff6f75bd5afaea2e2db06d8063841c17
from: Oliver Lowe <o@olowe.co>
date: Sat Dec 18 04:08:54 2021 UTC

cmd/recursor: comments on caching records

With an explanation of why we lookup before we insert into the cache

commit - b141f1193309066d69c8a1759da0d6cf4d6d60b7
commit + 590fd1b7ff6f75bd5afaea2e2db06d8063841c17
blob - a357cbedc5c26b689636d6572573aaa08d48b2cb
blob + fc31993872bcb976e731fab525902ed6d61cd4f1
--- cmd/recursor/resolve.go
+++ cmd/recursor/resolve.go
@@ -88,6 +88,8 @@ func resolve(q dnsmessage.Question, next []net.IP, dep
 	}
 	fmt.Println("no auth answer")
 
+	// cache resource records from authorities, additionals sections if we
+	// don't have them already (i.e. from authoritative answers)
 	if len(rmsg.Authorities) > 0 {
 		if _, ok := lookup(rmsg.Authorities[0].Header.Name, rmsg.Authorities[0].Header.Type); !ok {
 			insert(rmsg.Authorities[0].Header.Name, rmsg.Authorities[0].Header.Type, rmsg.Authorities)