Add secondary support

Allow specifying a primary server and retrieve the zone's content.

Add tests and an Expired bool to zone struct, to stop server zones

that are expired. The zone is retrieved on Startup, no updates of

changed content are done. We also don't respond to notifies yet.

middleware/file/notify.go

@@ -10,31 +10,31 @@ import (
 
 // Notify will send notifies to all configured IP addresses.
 func (z *Zone) Notify() {
-	go notify(z.name, z.Peers)
+	go notify(z.name, z.TransferTo)
 }
 
-// notify sends notifies to the configured remotes. It will try up to three times
-// before giving up on a specific remote. We will sequentially loop through the remotes
+// notify sends notifies to the configured remote servers. It will try up to three times
+// before giving up on a specific remote. We will sequentially loop through "to"
 // until they all have replied (or have 3 failed attempts).
-func notify(zone string, remotes []string) error {
+func notify(zone string, to []string) error {
 	m := new(dns.Msg)
 	m.SetNotify(zone)
 	c := new(dns.Client)
 
 	// TODO(miek): error handling? Run this in a goroutine?
-	for _, remote := range remotes {
-		notifyRemote(c, m, middleware.Addr(remote).Standard())
+	for _, t := range to {
+		notifyAddr(c, m, t)
 	}
 	return nil
 }
 
-func notifyRemote(c *dns.Client, m *dns.Msg, s string) error {
+func notifyAddr(c *dns.Client, m *dns.Msg, s string) error {
 	for i := 0; i < 3; i++ {
 		ret, err := middleware.Exchange(c, m, s)
 		if err == nil && ret.Rcode == dns.RcodeSuccess || ret.Rcode == dns.RcodeNotImplemented {
 			return nil
 		}
-		// timeout? mean don't want it. should stop sending as well
+		// timeout? mean don't want it. should stop sending as well?
 	}
 	return fmt.Errorf("failed to send notify for zone '%s' to '%s'", m.Question[0].Name, s)
 }