Fix router race condition

router/default.go

@@ -513,25 +513,28 @@ func (r *router) advertiseEvents() error {
 
 // close closes exit channels
 func (r *router) close() {
-	// notify all goroutines to finish
+	log.Debugf("Router closing remaining channels")
-	close(r.exit)
-
 	// drain the advertise channel only if advertising
 	if r.status.Code == Advertising {
 		// drain the event channel
 		for range r.eventChan {
 		}
 
-		r.sub.RLock()
 		// close advert subscribers
 		for id, sub := range r.subscribers {
+			select {
+			case <-sub:
+			default:
+			}
+
 			// close the channel
 			close(sub)
 
 			// delete the subscriber
+			r.sub.Lock()
 			delete(r.subscribers, id)
+			r.sub.Unlock()
 		}
-		r.sub.RUnlock()
 	}
 
 	// mark the router as Stopped and set its Error to nil
@@ -552,6 +555,9 @@ func (r *router) watchErrors() {
 	defer r.Unlock()
 	// if the router is not stopped, stop it
 	if r.status.Code != Stopped {
+		// notify all goroutines to finish
+		close(r.exit)
+
 		// close all the channels
 		r.close()
 		// set the status error
@@ -857,6 +863,9 @@ func (r *router) Stop() error {
 		r.Unlock()
 		return r.status.Error
 	case Running, Advertising:
+		// notify all goroutines to finish
+		close(r.exit)
+
 		// close all the channels
 		// NOTE: close marks the router status as Stopped
 		r.close()