(kustomize/v1, go/v3) : Add new LeaderElectionReleaseOnCancel as true option commented to let users know when they can use it

Author: NikhilSharmaWe

pkg/plugins/common/kustomize/v1/scaffolds/internal/templates/config/manager/controller_manager_config.go

@@ -55,4 +55,14 @@ webhook:
 leaderElection:
   leaderElect: true
   resourceName: {{ hashFNV .Repo }}.{{ .Domain }}
+#   leaderElectionReleaseOnCancel defines if the leader should step down volume 
+#   when the Manager ends. This requires the binary to immediately end when the
+#   Manager is stopped, otherwise, this setting is unsafe. Setting this significantly
+#   speeds up voluntary leader transitions as the new leader don't have to wait
+#   LeaseDuration time first.
+#   In the default scaffold provided, the program ends immediately after 
+#   the manager stops, so would be fine to enable this option. However, 
+#   if you are doing or is intended to do any operation such as perform cleanups 
+#   after the manager stops then its usage might be unsafe.
+#   leaderElectionReleaseOnCancel: true
 `

pkg/plugins/golang/v3/scaffolds/internal/templates/main.go

@@ -245,6 +245,17 @@ func main() {
 		HealthProbeBindAddress: probeAddr,
 		LeaderElection:         enableLeaderElection,
 		LeaderElectionID:       "{{ hashFNV .Repo }}.{{ .Domain }}",
+		// LeaderElectionReleaseOnCancel defines if the leader should step down voluntarily
+		// when the Manager ends. This requires the binary to immediately end when the
+		// Manager is stopped, otherwise, this setting is unsafe. Setting this significantly
+		// speeds up voluntary leader transitions as the new leader don't have to wait
+		// LeaseDuration time first.
+		//
+		// In the default scaffold provided, the program ends immediately after 
+		// the manager stops, so would be fine to enable this option. However, 
+		// if you are doing or is intended to do any operation such as perform cleanups 
+		// after the manager stops then its usage might be unsafe.
+		// LeaderElectionReleaseOnCancel: true,
 	})
 {{- else }}
 	var err error

testdata/project-v3-addon/config/manager/controller_manager_config.yaml

@@ -9,3 +9,13 @@ webhook:
 leaderElection:
   leaderElect: true
   resourceName: 52ea9610.testproject.org
+#   leaderElectionReleaseOnCancel defines if the leader should step down volume 
+#   when the Manager ends. This requires the binary to immediately end when the
+#   Manager is stopped, otherwise, this setting is unsafe. Setting this significantly
+#   speeds up voluntary leader transitions as the new leader don't have to wait
+#   LeaseDuration time first.
+#   In the default scaffold provided, the program ends immediately after 
+#   the manager stops, so would be fine to enable this option. However, 
+#   if you are doing or is intended to do any operation such as perform cleanups 
+#   after the manager stops then its usage might be unsafe.
+#   leaderElectionReleaseOnCancel: true

testdata/project-v3-addon/main.go

@@ -72,6 +72,17 @@ func main() {
 		HealthProbeBindAddress: probeAddr,
 		LeaderElection:         enableLeaderElection,
 		LeaderElectionID:       "52ea9610.testproject.org",
+		// LeaderElectionReleaseOnCancel defines if the leader should step down voluntarily
+		// when the Manager ends. This requires the binary to immediately end when the
+		// Manager is stopped, otherwise, this setting is unsafe. Setting this significantly
+		// speeds up voluntary leader transitions as the new leader don't have to wait
+		// LeaseDuration time first.
+		//
+		// In the default scaffold provided, the program ends immediately after
+		// the manager stops, so would be fine to enable this option. However,
+		// if you are doing or is intended to do any operation such as perform cleanups
+		// after the manager stops then its usage might be unsafe.
+		// LeaderElectionReleaseOnCancel: true,
 	})
 	if err != nil {
 		setupLog.Error(err, "unable to start manager")

testdata/project-v3-config/config/manager/controller_manager_config.yaml

@@ -9,3 +9,13 @@ webhook:
 leaderElection:
   leaderElect: true
   resourceName: 6858fb70.testproject.org
+#   leaderElectionReleaseOnCancel defines if the leader should step down volume 
+#   when the Manager ends. This requires the binary to immediately end when the
+#   Manager is stopped, otherwise, this setting is unsafe. Setting this significantly
+#   speeds up voluntary leader transitions as the new leader don't have to wait
+#   LeaseDuration time first.
+#   In the default scaffold provided, the program ends immediately after 
+#   the manager stops, so would be fine to enable this option. However, 
+#   if you are doing or is intended to do any operation such as perform cleanups 
+#   after the manager stops then its usage might be unsafe.
+#   leaderElectionReleaseOnCancel: true

testdata/project-v3-multigroup/config/manager/controller_manager_config.yaml

@@ -9,3 +9,13 @@ webhook:
 leaderElection:
   leaderElect: true
   resourceName: 14be1926.testproject.org
+#   leaderElectionReleaseOnCancel defines if the leader should step down volume 
+#   when the Manager ends. This requires the binary to immediately end when the
+#   Manager is stopped, otherwise, this setting is unsafe. Setting this significantly
+#   speeds up voluntary leader transitions as the new leader don't have to wait
+#   LeaseDuration time first.
+#   In the default scaffold provided, the program ends immediately after 
+#   the manager stops, so would be fine to enable this option. However, 
+#   if you are doing or is intended to do any operation such as perform cleanups 
+#   after the manager stops then its usage might be unsafe.
+#   leaderElectionReleaseOnCancel: true

testdata/project-v3-multigroup/main.go

@@ -97,6 +97,17 @@ func main() {
 		HealthProbeBindAddress: probeAddr,
 		LeaderElection:         enableLeaderElection,
 		LeaderElectionID:       "14be1926.testproject.org",
+		// LeaderElectionReleaseOnCancel defines if the leader should step down voluntarily
+		// when the Manager ends. This requires the binary to immediately end when the
+		// Manager is stopped, otherwise, this setting is unsafe. Setting this significantly
+		// speeds up voluntary leader transitions as the new leader don't have to wait
+		// LeaseDuration time first.
+		//
+		// In the default scaffold provided, the program ends immediately after
+		// the manager stops, so would be fine to enable this option. However,
+		// if you are doing or is intended to do any operation such as perform cleanups
+		// after the manager stops then its usage might be unsafe.
+		// LeaderElectionReleaseOnCancel: true,
 	})
 	if err != nil {
 		setupLog.Error(err, "unable to start manager")

testdata/project-v3-v1beta1/config/manager/controller_manager_config.yaml

@@ -9,3 +9,13 @@ webhook:
 leaderElection:
   leaderElect: true
   resourceName: 2eab85d8.testproject.org
+#   leaderElectionReleaseOnCancel defines if the leader should step down volume 
+#   when the Manager ends. This requires the binary to immediately end when the
+#   Manager is stopped, otherwise, this setting is unsafe. Setting this significantly
+#   speeds up voluntary leader transitions as the new leader don't have to wait
+#   LeaseDuration time first.
+#   In the default scaffold provided, the program ends immediately after 
+#   the manager stops, so would be fine to enable this option. However, 
+#   if you are doing or is intended to do any operation such as perform cleanups 
+#   after the manager stops then its usage might be unsafe.
+#   leaderElectionReleaseOnCancel: true

testdata/project-v3-v1beta1/main.go

@@ -72,6 +72,17 @@ func main() {
 		HealthProbeBindAddress: probeAddr,
 		LeaderElection:         enableLeaderElection,
 		LeaderElectionID:       "2eab85d8.testproject.org",
+		// LeaderElectionReleaseOnCancel defines if the leader should step down voluntarily
+		// when the Manager ends. This requires the binary to immediately end when the
+		// Manager is stopped, otherwise, this setting is unsafe. Setting this significantly
+		// speeds up voluntary leader transitions as the new leader don't have to wait
+		// LeaseDuration time first.
+		//
+		// In the default scaffold provided, the program ends immediately after
+		// the manager stops, so would be fine to enable this option. However,
+		// if you are doing or is intended to do any operation such as perform cleanups
+		// after the manager stops then its usage might be unsafe.
+		// LeaderElectionReleaseOnCancel: true,
 	})
 	if err != nil {
 		setupLog.Error(err, "unable to start manager")

testdata/project-v3/config/manager/controller_manager_config.yaml

@@ -9,3 +9,13 @@ webhook:
 leaderElection:
   leaderElect: true
   resourceName: dd1da13f.testproject.org
+#   leaderElectionReleaseOnCancel defines if the leader should step down volume 
+#   when the Manager ends. This requires the binary to immediately end when the
+#   Manager is stopped, otherwise, this setting is unsafe. Setting this significantly
+#   speeds up voluntary leader transitions as the new leader don't have to wait
+#   LeaseDuration time first.
+#   In the default scaffold provided, the program ends immediately after 
+#   the manager stops, so would be fine to enable this option. However, 
+#   if you are doing or is intended to do any operation such as perform cleanups 
+#   after the manager stops then its usage might be unsafe.
+#   leaderElectionReleaseOnCancel: true