OADP-823: Address oadp-1.0.z with ocp 4.11 csi compatibility issue (#848)

* address oadp-1.0.z with ocp 4.11 csi compatibility issue

* remove version info logs

* remove redundant plugin loop

* update validation error message

Author: shubham-pampattiwar

controllers/validator.go

@@ -3,6 +3,9 @@ package controllers
 import (
 	"errors"
 	"fmt"
+	"k8s.io/apimachinery/pkg/version"
+	"k8s.io/client-go/kubernetes"
+	"sigs.k8s.io/controller-runtime/pkg/client/config"
 
 	"github.com/go-logr/logr"
 	oadpv1alpha1 "github.com/openshift/oadp-operator/api/v1alpha1"
@@ -85,6 +88,19 @@ func (r *DPAReconciler) ValidateVeleroPlugins(log logr.Logger) (bool, error) {
 	var defaultPlugin oadpv1alpha1.DefaultPlugin
 	for _, plugin := range dpa.Spec.Configuration.Velero.DefaultPlugins {
 
+		// check csi compatibility with cluster version
+		// velero version <1.9 expects API group snapshot.storage.k8s.io/v1beta1, while OCP 4.11 (k8s 1.24) has only snapshot.storage.k8s.io/v1
+		if plugin == oadpv1alpha1.DefaultPluginCSI {
+			clusterVersion, err := getClusterVersion()
+			if err != nil {
+				return false, err
+			}
+
+			if clusterVersion.Major == "1" && clusterVersion.Minor >= "24" {
+				return false, errors.New("csi plugin on OADP 1.0 (velero <1.9) requires API snapshot.storage.k8s.io/v1beta1. On OCP 4.11+ (k8s 1.24+), to use CSI, upgrade to OADP 1.1+")
+			}
+		}
+
 		pluginSpecificMap, ok := credentials.PluginSpecificFields[plugin]
 		pluginNeedsCheck, foundInBSLorVSL := providerNeedsDefaultCreds[string(plugin)]
 
@@ -103,3 +119,12 @@ func (r *DPAReconciler) ValidateVeleroPlugins(log logr.Logger) (bool, error) {
 	}
 	return true, nil
 }
+
+func getClusterVersion() (*version.Info, error) {
+	kubeConf := config.GetConfigOrDie()
+	clientset, err := kubernetes.NewForConfig(kubeConf)
+	if err != nil {
+		return nil, err
+	}
+	return clientset.Discovery().ServerVersion()
+}