K8SPSMDB-1466 improve MCS error handling to prevent operator crashes (#2044)

* K8SPSMDB-1466 improve MCS error handling to prevent operator crashes

* add more logs :)

* improve tests

Author: hors

cmd/manager/main.go

@@ -148,7 +148,7 @@ func main() {
 		os.Exit(1)
 	}
 
-	if err := mcs.Register(discovery.NewDiscoveryClientForConfigOrDie(config)); err != nil {
+	if err := mcs.Register(discovery.NewDiscoveryClientForConfigOrDie(config), setupLog); err != nil {
 		setupLog.Error(err, "failed to register multicluster service")
 		os.Exit(1)
 	}

pkg/mcs/register.go

@@ -1,7 +1,7 @@
 package mcs
 
 import (
-	"github.com/pkg/errors"
+	"github.com/go-logr/logr"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
@@ -33,10 +33,14 @@ func addKnownTypes(scheme *runtime.Scheme) error {
 	return nil
 }
 
-func Register(dc *discovery.DiscoveryClient) error {
+func Register(dc *discovery.DiscoveryClient, log logr.Logger) error {
 	resources, err := dc.ServerPreferredResources()
 	if err != nil {
-		return errors.Wrap(err, "get api groups and resources")
+		// MCS is optional functionality - if discovery fails for any reason,
+		// mark it as unavailable and continue without crashing the operator
+		available = false
+		log.Info("Multi-cluster services (MCS) are not available: failed to discover API resources", "error", err)
+		return nil
 	}
 
 outer:
@@ -53,6 +57,7 @@ outer:
 
 	if MCSSchemeGroupVersion.Group == "" {
 		available = false
+		log.Info("Multi-cluster services (MCS) are not available: ServiceExport resource not found in cluster")
 		return nil
 	}
 

pkg/mcs/register_test.go

@@ -0,0 +1,35 @@
+package mcs
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestIsAvailable(t *testing.T) {
+	available = true
+	assert.True(t, IsAvailable())
+
+	available = false
+	assert.False(t, IsAvailable())
+}
+
+func TestServiceExport(t *testing.T) {
+	namespace := "test-namespace"
+	name := "test-service"
+	labels := map[string]string{
+		"app": "test",
+	}
+
+	se := ServiceExport(namespace, name, labels)
+
+	assert.Equal(t, name, se.Name)
+	assert.Equal(t, namespace, se.Namespace)
+	assert.Equal(t, "test", se.Labels["app"])
+}
+
+func TestServiceExportList(t *testing.T) {
+	seList := ServiceExportList()
+
+	assert.Equal(t, "ServiceExportList", seList.Kind)
+}