From 9c4b791621344edb7ed36e4cc6aa88bed9876681 Mon Sep 17 00:00:00 2001
From: Eugene Bujak <hmage@hmage.net>
Date: Wed, 28 Nov 2018 18:57:20 +0300
Subject: [PATCH] coredns reload -> dnsServer.Reconfigure()

---
 control.go | 12 ++++--------
 coredns.go | 27 ++++++++++++++++++++++-----
 2 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/control.go b/control.go
index d2011cb0..25c059b0 100644
--- a/control.go
+++ b/control.go
@@ -38,17 +38,13 @@ var client = &http.Client{
 // -------------------
 // coredns run control
 // -------------------
-func tellCoreDNSToReload() {
-	corednsplugin.Reload <- true
-}
-
 func writeAllConfigsAndReloadCoreDNS() error {
 	err := writeAllConfigs()
 	if err != nil {
 		log.Printf("Couldn't write all configs: %s", err)
 		return err
 	}
-	tellCoreDNSToReload()
+	reconfigureDNSServer()
 	return nil
 }
 
@@ -155,7 +151,7 @@ func handleSetUpstreamDNS(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, errorText, http.StatusInternalServerError)
 		return
 	}
-	tellCoreDNSToReload()
+	reconfigureDNSServer()
 	_, err = fmt.Fprintf(w, "OK %d servers\n", len(hosts))
 	if err != nil {
 		errorText := fmt.Sprintf("Couldn't write body: %s", err)
@@ -386,7 +382,7 @@ func handleFilteringAddURL(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	tellCoreDNSToReload()
+	reconfigureDNSServer()
 
 	_, err = fmt.Fprintf(w, "OK %d rules\n", filter.RulesCount)
 	if err != nil {
@@ -571,7 +567,7 @@ func refreshFiltersIfNeccessary(force bool) int {
 	config.Unlock()
 
 	if updateCount > 0 {
-		tellCoreDNSToReload()
+		reconfigureDNSServer()
 	}
 	return updateCount
 }
diff --git a/coredns.go b/coredns.go
index b612c8d0..348b4241 100644
--- a/coredns.go
+++ b/coredns.go
@@ -15,11 +15,7 @@ func isRunning() bool {
 	return dnsServer.IsRunning()
 }
 
-func startDNSServer() error {
-	if isRunning() {
-		return fmt.Errorf("Unable to start coreDNS: Already running")
-	}
-
+func generateServerConfig() dnsforward.ServerConfig {
 	filters := []dnsforward.Filter{}
 	for _, filter := range config.Filters {
 		filters = append(filters, dnsforward.Filter{
@@ -43,7 +39,15 @@ func startDNSServer() error {
 		}
 		newconfig.Upstreams = append(newconfig.Upstreams, upstream)
 	}
+	return newconfig
+}
 
+func startDNSServer() error {
+	if isRunning() {
+		return fmt.Errorf("Unable to start forwarding DNS server: Already running")
+	}
+
+	newconfig := generateServerConfig()
 	err := dnsServer.Start(&newconfig)
 	if err != nil {
 		return errorx.Decorate(err, "Couldn't start forwarding DNS server")
@@ -51,3 +55,16 @@ func startDNSServer() error {
 
 	return nil
 }
+
+func reconfigureDNSServer() error {
+	if !isRunning() {
+		return fmt.Errorf("Refusing to reconfigure forwarding DNS server: not running")
+	}
+
+	err := dnsServer.Reconfigure(generateServerConfig())
+	if err != nil {
+		return errorx.Decorate(err, "Couldn't start forwarding DNS server")
+	}
+
+	return nil
+}