fix(shutdown): fix crash when shutting down before server and task scheduler have started. (#2148)

init shutdown routine after controller.Init()
check for nil values before stopping http server and task scheduler.

Signed-off-by: Petu Eusebiu <peusebiu@cisco.com>

pkg/api/controller.go

@@ -370,13 +370,18 @@ func (c *Controller) LoadNewConfig(newConfig *config.Config) {
 
 func (c *Controller) Shutdown() {
 	c.StopBackgroundTasks()
-	ctx := context.Background()
-	_ = c.Server.Shutdown(ctx)
+
+	if c.Server != nil {
+		ctx := context.Background()
+		_ = c.Server.Shutdown(ctx)
+	}
 }
 
 // Will stop scheduler and wait for all tasks to finish their work.
 func (c *Controller) StopBackgroundTasks() {
-	c.taskScheduler.Shutdown()
+	if c.taskScheduler != nil {
+		c.taskScheduler.Shutdown()
+	}
 }
 
 func (c *Controller) StartBackgroundTasks() {

pkg/cli/server/config_reloader.go

@@ -41,8 +41,6 @@ func signalHandler(ctlr *api.Controller, sigCh chan os.Signal) {
 
 		// gracefully shutdown http server
 		ctlr.Shutdown() //nolint: contextcheck
-
-		close(sigCh)
 	}
 }
 
@@ -61,8 +59,6 @@ func initShutDownRoutine(ctlr *api.Controller) {
 func (hr *HotReloader) Start() {
 	done := make(chan bool)
 
-	initShutDownRoutine(hr.ctlr)
-
 	// run watcher
 	go func() {
 		defer hr.watcher.Close()

pkg/cli/server/root.go

@@ -69,6 +69,8 @@ func newServeCmd(conf *config.Config) *cobra.Command {
 				return err
 			}
 
+			initShutDownRoutine(ctlr)
+
 			if err := ctlr.Run(); err != nil {
 				log.Error().Err(err).Msg("failed to start controller, exiting")
 			}