issue-588, check for no external IPs or private cluster in PostgreSQL…

… webhook is implemented

apis/clusters/v1beta1/postgresql_webhook.go

@@ -20,8 +20,10 @@ import (
 	"context"
 	"fmt"
 
+	k8sCore "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	ctrl "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/client"
 	logf "sigs.k8s.io/controller-runtime/pkg/log"
 	"sigs.k8s.io/controller-runtime/pkg/webhook"
 
@@ -32,13 +34,15 @@ import (
 var postgresqllog = logf.Log.WithName("postgresql-resource")
 
 type pgValidator struct {
-	API validation.Validation
+	API       validation.Validation
+	K8sClient client.Client
 }
 
 func (r *PostgreSQL) SetupWebhookWithManager(mgr ctrl.Manager, api validation.Validation) error {
 	return ctrl.NewWebhookManagedBy(mgr).
 		For(r).WithValidator(webhook.CustomValidator(&pgValidator{
-		API: api,
+		API:       api,
+		K8sClient: mgr.GetClient(),
 	})).
 		Complete()
 }
@@ -87,6 +91,13 @@ func (pgv *pgValidator) ValidateCreate(ctx context.Context, obj runtime.Object)
 		return err
 	}
 
+	if pg.Spec.UserRefs != nil {
+		err = pgv.validatePostgreSQLUsers(ctx, pg)
+		if err != nil {
+			return err
+		}
+	}
+
 	appVersions, err := pgv.API.ListAppVersions(models.PgAppKind)
 	if err != nil {
 		return fmt.Errorf("cannot list versions for kind: %v, err: %w",
@@ -165,6 +176,13 @@ func (pgv *pgValidator) ValidateUpdate(ctx context.Context, old runtime.Object,
 		return pgv.ValidateCreate(ctx, pg)
 	}
 
+	if pg.Spec.UserRefs != nil {
+		err := pgv.validatePostgreSQLUsers(ctx, pg)
+		if err != nil {
+			return err
+		}
+	}
+
 	err := pg.Spec.ValidateImmutableFieldsUpdate(oldCluster.Spec)
 	if err != nil {
 		return fmt.Errorf("immutable fields validation error: %v", err)
@@ -180,6 +198,32 @@ func (pgv *pgValidator) ValidateUpdate(ctx context.Context, old runtime.Object,
 	return nil
 }
 
+func (pgv *pgValidator) validatePostgreSQLUsers(ctx context.Context, pg *PostgreSQL) error {
+	nodeList := &k8sCore.NodeList{}
+
+	err := pgv.K8sClient.List(ctx, nodeList, &client.ListOptions{})
+	if err != nil {
+		return fmt.Errorf("cannot list node list, error: %v", err)
+	}
+
+	var externalIPExists bool
+	for _, node := range nodeList.Items {
+		for _, nodeAddress := range node.Status.Addresses {
+			if nodeAddress.Type == k8sCore.NodeExternalIP {
+				externalIPExists = true
+				break
+			}
+		}
+	}
+
+	if !externalIPExists || pg.Spec.PrivateNetworkCluster {
+		return fmt.Errorf("cannot create PostgreSQL user, if your cluster is private or has no external ips " +
+			"you need to configure peering and remove user references from cluster specification")
+	}
+
+	return nil
+}
+
 // ValidateDelete implements webhook.Validator so a webhook will be registered for the type
 func (pgv *pgValidator) ValidateDelete(ctx context.Context, obj runtime.Object) error {
 	pg, ok := obj.(*PostgreSQL)