Revert "Implement notifies for transfer plugin (#3972)" (#3995)

This reverts commit 68f1dd5ddf.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

plugin/auto/setup.go

@@ -10,8 +10,8 @@ import (
 	"github.com/coredns/coredns/plugin"
 	"github.com/coredns/coredns/plugin/metrics"
 	clog "github.com/coredns/coredns/plugin/pkg/log"
+	"github.com/coredns/coredns/plugin/pkg/parse"
 	"github.com/coredns/coredns/plugin/pkg/upstream"
-	"github.com/coredns/coredns/plugin/transfer"
 
 	"github.com/caddyserver/caddy"
 )
@@ -28,13 +28,10 @@ func setup(c *caddy.Controller) error {
 
 	c.OnStartup(func() error {
 		m := dnsserver.GetConfig(c).Handler("prometheus")
-		if m != nil {
-			(&a).metrics = m.(*metrics.Metrics)
-		}
-		t := dnsserver.GetConfig(c).Handler("transfer")
-		if t != nil {
-			(&a).transfer = t.(*transfer.Transfer)
+		if m == nil {
+			return nil
 		}
+		(&a).metrics = m.(*metrics.Metrics)
 		return nil
 	})
 
@@ -150,6 +147,15 @@ func autoParse(c *caddy.Controller) (Auto, error) {
 				// remove soon
 				c.RemainingArgs() // eat remaining args
 
+			case "transfer":
+				t, _, e := parse.Transfer(c, false)
+				if e != nil {
+					return a, e
+				}
+				if t != nil {
+					a.loader.transferTo = append(a.loader.transferTo, t...)
+				}
+
 			default:
 				return Auto{}, c.Errf("unknown property '%s'", c.Val())
 			}