From 75bd0b83a479997da1940e048d5161b11cecb303 Mon Sep 17 00:00:00 2001
From: Cheng Wang <wangchengiscool@gmail.com>
Date: Thu, 7 Sep 2023 20:01:58 +0800
Subject: [PATCH] fix: Workflow controller crash on nil pointer  (#11770)

---
 workflow/controller/healthz.go | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/workflow/controller/healthz.go b/workflow/controller/healthz.go
index a0dcc92b8377..b1d882b40c9c 100644
--- a/workflow/controller/healthz.go
+++ b/workflow/controller/healthz.go
@@ -33,6 +33,11 @@ func (wfc *WorkflowController) Healthz(w http.ResponseWriter, r *http.Request) {
 		if err != nil {
 			return err
 		}
+		// the wfc.wfInformer is nil if it is not the leader
+		if wfc.wfInformer == nil {
+			log.Info("healthz: current pod is not the leader")
+			return nil
+		}
 		lister := v1alpha1.NewWorkflowLister(wfc.wfInformer.GetIndexer())
 		list, err := lister.Workflows(wfc.managedNamespace).List(seletor)
 		if err != nil {