From 0ac24197fe63d48be29a62c6b0cc8e2f129a4dd2 Mon Sep 17 00:00:00 2001
From: Aly Nathoo <98403872+anathoodell@users.noreply.github.com>
Date: Fri, 6 Dec 2024 09:18:43 -0500
Subject: [PATCH] Detect Zone info in node labels  (#811)

* Adding GetMatchingNodes as a function to find Nodes that have labels that match label and label value.

Signed-off-by: Aly Nathoo <aly.nathoo@dell.com>

---------

Signed-off-by: Aly Nathoo <aly.nathoo@dell.com>
---
 controllers/csm_controller.go      | 10 ++++++
 controllers/csm_controller_test.go | 54 ++++++++++++++++++++++++++++++
 tests/shared/common.go             | 13 +++++++
 tests/shared/crclient/client.go    | 14 ++++++++
 4 files changed, 91 insertions(+)

diff --git a/controllers/csm_controller.go b/controllers/csm_controller.go
index 997a516c0..05a1054da 100644
--- a/controllers/csm_controller.go
+++ b/controllers/csm_controller.go
@@ -1517,3 +1517,13 @@ func (r *ContainerStorageModuleReconciler) GetUpdateCount() int32 {
 func (r *ContainerStorageModuleReconciler) GetK8sClient() kubernetes.Interface {
 	return r.K8sClient
 }
+
+func (r *ContainerStorageModuleReconciler) GetMatchingNodes(ctx context.Context, labelKey string, labelValue string) (*corev1.NodeList, error) {
+	nodeList := &corev1.NodeList{}
+	opts := []client.ListOption{
+		client.MatchingLabels{labelKey: labelValue},
+	}
+	err := r.List(ctx, nodeList, opts...)
+
+	return nodeList, err
+}
diff --git a/controllers/csm_controller_test.go b/controllers/csm_controller_test.go
index 91e111651..3b80ecbe0 100644
--- a/controllers/csm_controller_test.go
+++ b/controllers/csm_controller_test.go
@@ -2382,3 +2382,57 @@ func (suite *CSMControllerTestSuite) makeFakeRevProxyCSM(name string, ns string,
 	err = suite.fakeClient.Create(ctx, &csm)
 	assert.Nil(suite.T(), err)
 }
+
+func (suite *CSMControllerTestSuite) TestGetNodeLabels() {
+	// TBD: crclient/client.go needs to be augmented to filter on labels during
+	// the List return for a viable thorough test. Since this functionality is
+	// missing, this test is quite elementary as a result.
+
+	csm := shared.MakeCSM(csmName, suite.namespace, configVersion)
+	csm.Spec.Driver.CSIDriverType = csmv1.PowerScale
+	csm.Spec.Driver.Common.Image = "image"
+	csm.Annotations[configVersionKey] = configVersion
+
+	sec := shared.MakeSecret(csmName+"-creds", suite.namespace, configVersion)
+	err := suite.fakeClient.Create(ctx, sec)
+	if err != nil {
+		panic(err)
+	}
+
+	csm.ObjectMeta.Finalizers = []string{CSMFinalizerName}
+	err = suite.fakeClient.Create(ctx, &csm)
+	if err != nil {
+		panic(err)
+	}
+
+	reconciler := suite.createReconciler()
+
+	// create node object, add to fakeclient, reconcile.GetMatchingNodes
+	node := shared.MakeNode("node1", suite.namespace)
+	node.Labels["topology.kubernetes.io/zone"] = "US-EAST"
+
+	err = suite.fakeClient.Create(ctx, &node)
+	assert.Nil(suite.T(), err)
+
+	nodeList := &corev1.NodeList{}
+	err = suite.fakeClient.List(ctx, nodeList, nil)
+	assert.Nil(suite.T(), err)
+
+	nodeListMatching, err := reconciler.GetMatchingNodes(ctx, "topology.kubernetes.io/zone", "US-EAST")
+	ctrl.Log.Info("node list response (1)", "number of nodes is: ", len(nodeListMatching.Items))
+
+	// Check the len to be 1 else fail
+	if len(nodeListMatching.Items) != 1 {
+		ctrl.Log.Error(err, "Unexpected length on node list.", "length", len(nodeListMatching.Items))
+		panic(err)
+	}
+
+	for _, node := range nodeListMatching.Items {
+		ctrl.Log.Info("Matching node item", "name ", node.ObjectMeta.GetName())
+	}
+	if node.ObjectMeta.GetName() != "node1" {
+		ctrl.Log.Error(err, "Unmatched label on node.")
+		panic(err)
+	}
+	assert.Nil(suite.T(), err)
+}
diff --git a/tests/shared/common.go b/tests/shared/common.go
index 2855cd45f..fc48d6ae4 100644
--- a/tests/shared/common.go
+++ b/tests/shared/common.go
@@ -195,6 +195,19 @@ func MakePod(name, ns string) corev1.Pod {
 	return podObj
 }
 
+// MakeNode returns a node object
+func MakeNode(name, ns string) corev1.Node {
+	nodeObj := corev1.Node{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      name,
+			Namespace: ns,
+			Labels:    map[string]string{},
+		},
+	}
+
+	return nodeObj
+}
+
 // MakeReverseProxyModule returns a csireverseproxy object
 func MakeReverseProxyModule(_ string) csmv1.Module {
 	revproxy := csmv1.Module{
diff --git a/tests/shared/crclient/client.go b/tests/shared/crclient/client.go
index a6d1d0f42..ee6be3443 100644
--- a/tests/shared/crclient/client.go
+++ b/tests/shared/crclient/client.go
@@ -106,6 +106,8 @@ func (f Client) List(ctx context.Context, list client.ObjectList, _ ...client.Li
 	switch l := list.(type) {
 	case *corev1.PodList:
 		return f.listPodList(l)
+	case *corev1.NodeList:
+		return f.listNodeList(l)
 	case *appsv1.DeploymentList:
 		return f.listDeploymentList(ctx, &appsv1.DeploymentList{})
 	default:
@@ -122,6 +124,18 @@ func (f Client) listPodList(list *corev1.PodList) error {
 	return nil
 }
 
+func (f Client) listNodeList(list *corev1.NodeList) error {
+	for k, v := range f.Objects {
+		if k.Kind == "Node" {
+			node, ok := v.(*corev1.Node)
+			if ok {
+				list.Items = append(list.Items, *node)
+			}
+		}
+	}
+	return nil
+}
+
 func (f Client) listDeploymentList(_ context.Context, list *appsv1.DeploymentList) error {
 	for k, v := range f.Objects {
 		if k.Kind == "Deployment" {