Slack URL is specified, but not getting notice

[mabushey]

✗  kubectl -n kube-system exec -it  pod/node-termination-handler-s8nkk -- sh
/app # apk add curl
...
OK: 7 MiB in 19 packages
/app # curl -X POST -H 'Content-type: application/json' --data '{"text":"Manual message from inside pod/node-termination-handler-s8nkk"}' $SLACK_WEBHOOK_URL
ok/app #

The message goes to Slack.

✗  gcloud compute instances simulate-maintenance-event [redacted]-n2d-standard-4-preemptibl-9f1a666f-177n --zone=us-central1-a
Simulating maintenance on instance(s) [https://compute.googleapis.com/compute/v1/projects/[redacted]/zones/us-central1-a/instances/[redacted]-n2d-standard-4-preemptibl-9f1a666f-177n]...done.

✗  kubectl -n kube-system logs -f node-termination-handler-s8nkk
...
 I1119 22:48:46.179414   46739 gceTerminationHandler.go:135] Handling maintenance event with state: "TRUE"                                                                                                                                                                        
I1119 22:48:46.179484   46739 gceTerminationHandler.go:141] Recording impending termination                                                                                                                                                                                      
I1119 22:48:46.179630   46739 handler.go:54] Current node state: {[redacted]-n2d-standard-4-preemptibl-f73d7c1b-t9x5 true 2020-11-19 22:49:16.179487009 +0000 UTC m=+6840.282105137 false}                                                                                      
I1119 22:48:46.179826   46739 handler.go:64] Applying taint prior to handling termination 
...

We have a impending termination, but there is no slack notification... :(

[evilr00t]

Similar thing here, looks like slack code is completely skipped(?)

glog.V(4).Infof("Applying taint prior to handling termination")
if err := sendSlack(); err != nil {
	glog.Errorf("Failed to send slack: %v", err)
}