add volumegroupreplicationclass controller code

docs/volumegroupreplicationclass.md

@@ -0,0 +1,24 @@
+# VolumeGroupReplicationClass
+
+VolumeGroupReplicationClass is a cluster scoped resource that contains driver related configuration parameters for volume group replication.
+
+`provisioner` is name of the storage provisioner.
+
+`parameters` contains key-value pairs that are passed down to the driver. Users can add their own key-value pairs. Keys with `replication.storage.openshift.io/` prefix are reserved by operator and not passed down to the driver.
+
+## Reserved parameter keys
+
+- `replication.storage.openshift.io/group-replication-secret-name`
+- `replication.storage.openshift.io/group-replication-secret-namespace`
+
+```yaml
+apiVersion: replication.storage.openshift.io/v1alpha1
+kind: VolumeGroupReplicationClass
+metadata:
+  name: volumegroupreplicationclass-sample
+spec:
+  provisioner: example.provisioner.io
+  parameters:
+    replication.storage.openshift.io/group-replication-secret-name: secret-name
+    replication.storage.openshift.io/group-replication-secret-namespace: secret-namespace
+```

internal/controller/replication.storage/parameters.go

@@ -29,8 +29,10 @@ const (
 	// Driver.
 	replicationParameterPrefix = "replication.storage.openshift.io/"
 
-	prefixedReplicationSecretNameKey      = replicationParameterPrefix + "replication-secret-name"      // name key for secret
-	prefixedReplicationSecretNamespaceKey = replicationParameterPrefix + "replication-secret-namespace" // namespace key secret
+	prefixedReplicationSecretNameKey           = replicationParameterPrefix + "replication-secret-name"            // name key for secret
+	prefixedReplicationSecretNamespaceKey      = replicationParameterPrefix + "replication-secret-namespace"       // namespace key secret
+	prefixedGroupReplicationSecretNameKey      = replicationParameterPrefix + "group-replication-secret-name"      // name key for secret
+	prefixedGroupReplicationSecretNamespaceKey = replicationParameterPrefix + "group-replication-secret-namespace" // namespace key secret
 )
 
 // filterPrefixedParameters removes all the reserved keys from the
@@ -53,10 +55,14 @@ func validatePrefixedParameters(param map[string]string) error {
 		if strings.HasPrefix(k, replicationParameterPrefix) {
 			switch k {
 			case prefixedReplicationSecretNameKey:
+				fallthrough
+			case prefixedGroupReplicationSecretNameKey:
 				if v == "" {
 					return errors.New("secret name cannot be empty")
 				}
 			case prefixedReplicationSecretNamespaceKey:
+				fallthrough
+			case prefixedGroupReplicationSecretNamespaceKey:
 				if v == "" {
 					return errors.New("secret namespace cannot be empty")
 				}

internal/controller/replication.storage/volumegroupreplicationclass.go

@@ -0,0 +1,45 @@
+/*
+Copyright 2025 The Kubernetes-CSI-Addons 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 controller
+
+import (
+	"context"
+
+	"github.com/go-logr/logr"
+	"k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/types"
+
+	replicationv1alpha1 "github.com/csi-addons/kubernetes-csi-addons/api/replication.storage/v1alpha1"
+)
+
+// getVolumeGroupReplicationClass fetches the volumegroupreplicationclass object in the given namespace and return the same.
+// nolint:unused // Ignore unused function, will be updated later
+func (r VolumeGroupReplicationReconciler) getVolumeGroupReplicationClass(logger logr.Logger, vgrClassName string) (*replicationv1alpha1.VolumeGroupReplicationClass, error) {
+	vgrClassObj := &replicationv1alpha1.VolumeGroupReplicationClass{}
+	err := r.Client.Get(context.TODO(), types.NamespacedName{Name: vgrClassName}, vgrClassObj)
+	if err != nil {
+		if errors.IsNotFound(err) {
+			logger.Error(err, "VolumeGroupReplicationClass not found", "VolumeGroupReplicationClass", vgrClassName)
+		} else {
+			logger.Error(err, "Got an unexpected error while fetching VolumeGroupReplicationClass", "VolumeGroupReplicationClass", vgrClassName)
+		}
+
+		return nil, err
+	}
+
+	return vgrClassObj, nil
+}