fead: add lease monitor (#78)

* add feat lease monitor

* add comment

* rename runnable

* rename runnable

* add log

* add log

* add log

* add log

* add log

* add license

Author: ColdsteelRail

controller/runnable/initializer.go

@@ -0,0 +1,48 @@
+/*
+Copyright 2025 The KusionStack Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package runnable
+
+import (
+	"github.com/go-logr/logr"
+	controllerruntime "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/manager"
+
+	"kusionstack.io/kube-utils/metrics"
+)
+
+var runnable []manager.Runnable
+
+// InitializeRunnable initialize runnable for manager
+func InitializeRunnable(mgr manager.Manager, opts controllerruntime.Options) error {
+	// register leader metrics
+	metrics.RegisterLeaderRunningMetrics()
+	// register runnable
+	addRunnable(opts, mgr.GetLogger())
+	for _, runnable := range runnable {
+		if err := mgr.Add(runnable); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func addRunnable(opts controllerruntime.Options, logger logr.Logger) {
+	runnable = append(runnable,
+		&LeaderMetricsRunnable{leaseName: opts.LeaderElectionID, logger: logger},
+		&NoneLeaderMetricRunnable{enableLeaderElection: opts.LeaderElection, leaseName: opts.LeaderElectionID, logger: logger},
+	)
+}

controller/runnable/leader_monitor.go

@@ -0,0 +1,65 @@
+/*
+Copyright 2025 The KusionStack Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package runnable
+
+import (
+	"context"
+
+	"github.com/go-logr/logr"
+
+	"kusionstack.io/kube-utils/metrics"
+)
+
+// LeaderMetricsRunnable is a runnable that records the leader metrics
+type LeaderMetricsRunnable struct {
+	logger    logr.Logger
+	leaseName string
+}
+
+func (l LeaderMetricsRunnable) NeedLeaderElection() bool {
+	return true
+}
+
+func (l LeaderMetricsRunnable) Start(_ context.Context) error {
+	m := metrics.LeaderRunningMetrics{Lease: l.leaseName}
+	m.Lead()
+	l.logger.Info("leader election enabled, start LeaderMetricsRunnable, record leader metrics")
+	return nil
+}
+
+// NoneLeaderMetricRunnable is a runnable that records the none leader metrics
+type NoneLeaderMetricRunnable struct {
+	logger               logr.Logger
+	leaseName            string
+	enableLeaderElection bool
+}
+
+func (nl NoneLeaderMetricRunnable) NeedLeaderElection() bool {
+	return false
+}
+
+func (nl NoneLeaderMetricRunnable) Start(_ context.Context) error {
+	m := metrics.LeaderRunningMetrics{Lease: nl.leaseName}
+	if nl.enableLeaderElection {
+		m.UnLead()
+		nl.logger.Info("leader election enabled, start NoneLeaderMetricRunnable, record none leader metrics")
+	} else {
+		m.Lead()
+		nl.logger.Info("leader election disabled, start NoneLeaderMetricRunnable, record leader metrics")
+	}
+	return nil
+}

metrics/leader_election.go

@@ -0,0 +1,49 @@
+/*
+Copyright 2025 The KusionStack Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package metrics
+
+import (
+	"github.com/prometheus/client_golang/prometheus"
+	"sigs.k8s.io/controller-runtime/pkg/metrics"
+)
+
+var leaderRunningCount = "leader_running_gauge"
+
+var leaderRunningGaugeVec = prometheus.NewGaugeVec(
+	prometheus.GaugeOpts{
+		Subsystem: ReconcileSubSystem,
+		Name:      leaderRunningCount,
+		Help:      "leader controller set gauge to 1, otherwise set to 0",
+	},
+	[]string{"Lease"},
+)
+
+func RegisterLeaderRunningMetrics() {
+	metrics.Registry.MustRegister(leaderRunningGaugeVec)
+}
+
+type LeaderRunningMetrics struct {
+	Lease string
+}
+
+func (m *LeaderRunningMetrics) Lead() {
+	leaderRunningGaugeVec.WithLabelValues(m.Lease).Set(1)
+}
+
+func (m *LeaderRunningMetrics) UnLead() {
+	leaderRunningGaugeVec.WithLabelValues(m.Lease).Set(0)
+}