[DEVOPS-824] Delete metric if redis-failover no longer exist

metrics/dummy.go

@@ -8,3 +8,4 @@ type dummy struct{}
 
 func (d *dummy) SetClusterOK(namespace string, name string)    {}
 func (d *dummy) SetClusterError(namespace string, name string) {}
+func (d *dummy) DeleteCluster(namespace string, name string)   {}

metrics/metrics.go

@@ -15,6 +15,7 @@ const (
 type Instrumenter interface {
 	SetClusterOK(namespace string, name string)
 	SetClusterError(namespace string, name string)
+	DeleteCluster(namespace string, name string)
 }
 
 // PromMetrics implements the instrumenter so the metrics can be managed by Prometheus.
@@ -71,3 +72,8 @@ func (p *PromMetrics) SetClusterOK(namespace string, name string) {
 func (p *PromMetrics) SetClusterError(namespace string, name string) {
 	p.clusterOK.WithLabelValues(namespace, name).Set(0)
 }
+
+// DeleteCluster set the cluster status to Error
+func (p *PromMetrics) DeleteCluster(namespace string, name string) {
+	p.clusterOK.DeleteLabelValues(namespace, name)
+}

metrics/metrics_test.go

@@ -87,6 +87,27 @@ func TestPrometheusMetrics(t *testing.T) {
 			},
 			expCode: http.StatusOK,
 		},
+		{
+			name: "Deleting a cluster should remove it",
+			addMetrics: func(pm *metrics.PromMetrics) {
+				pm.SetClusterOK("testns1", "test")
+				pm.DeleteCluster("testns1", "test")
+			},
+			expMetrics: []string{},
+			expCode:    http.StatusOK,
+		},
+		{
+			name: "Deleting a cluster should remove only the desired one",
+			addMetrics: func(pm *metrics.PromMetrics) {
+				pm.SetClusterOK("testns1", "test")
+				pm.SetClusterOK("testns2", "test")
+				pm.DeleteCluster("testns1", "test")
+			},
+			expMetrics: []string{
+				`my_metrics_controller_cluster_ok{name="test",namespace="testns2"} 1`,
+			},
+			expCode: http.StatusOK,
+		},
 	}
 
 	for _, test := range tests {

operator/redisfailover/handler.go

@@ -3,6 +3,7 @@ package redisfailover
 import (
 	"context"
 	"fmt"
+	"strings"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
@@ -83,6 +84,10 @@ func (r *RedisFailoverHandler) Add(_ context.Context, obj runtime.Object) error
 
 // Delete handles the deletion of a RF.
 func (r *RedisFailoverHandler) Delete(_ context.Context, name string) error {
+	n := strings.Split(name, "/")
+	if len(n) >= 2 {
+		r.mClient.DeleteCluster(n[0], n[1])
+	}
 	// No need to do anything, it will be handled by the owner reference done
 	// on the creation.
 	r.logger.Debugf("ignoring, kubernetes GCs all using the objects OwnerReference metadata")