Allow the customization of the storage class for the PVC of pipelines

This commit enables to use storage classes other than the cluster-wide default storage class for the PVC of pipelines. The customization can be defined in the config map config-artifact-pvc.yaml - similar to how the size of the PVC can already be defined. By default, it will fallback to the cluster-wide default storage class. fixes tektoncd#1101

Author: Fabian-K

config/config-artifact-pvc.yaml

@@ -21,3 +21,5 @@ data:
   # size of the PVC volume
   # size: 5Gi
 
+  # storage class of the PVC volume
+  # storageClassName: storage-class-name

docs/install.md

@@ -109,6 +109,7 @@ The PVC option can be configured using a ConfigMap with the name
 `config-artifact-pvc` and the following attributes:
 
 - size: the size of the volume (5Gi by default)
+- storageClassName: the storage class of the volume (default storage class by default)
 
 The GCS storage bucket can be configured using a ConfigMap with the name
 `config-artifact-bucket` with the following attributes:

pkg/artifacts/artifact_storage_test.go

@@ -39,18 +39,21 @@ var (
 			Name:      "pipelineruntest",
 		},
 	}
-	persistentVolumeClaim = GetPersistentVolumeClaim(DefaultPvcSize)
-	quantityComparer      = cmp.Comparer(func(x, y resource.Quantity) bool {
+	defaultStorageClass   *string = nil
+	customStorageClass            = "custom-storage-class"
+	persistentVolumeClaim         = GetPersistentVolumeClaim(DefaultPvcSize, defaultStorageClass)
+	quantityComparer              = cmp.Comparer(func(x, y resource.Quantity) bool {
 		return x.Cmp(y) == 0
 	})
 )
 
-func GetPersistentVolumeClaim(size string) *corev1.PersistentVolumeClaim {
+func GetPersistentVolumeClaim(size string, storageClassName *string) *corev1.PersistentVolumeClaim {
 	pvc := &corev1.PersistentVolumeClaim{
 		ObjectMeta: metav1.ObjectMeta{Name: "pipelineruntest-pvc", Namespace: "foo", OwnerReferences: pipelinerun.GetOwnerReference()},
 		Spec: corev1.PersistentVolumeClaimSpec{
-			AccessModes: []corev1.PersistentVolumeAccessMode{corev1.ReadWriteOnce},
-			Resources:   corev1.ResourceRequirements{Requests: corev1.ResourceList{corev1.ResourceStorage: resource.MustParse(size)}},
+			AccessModes:      []corev1.PersistentVolumeAccessMode{corev1.ReadWriteOnce},
+			Resources:        corev1.ResourceRequirements{Requests: corev1.ResourceList{corev1.ResourceStorage: resource.MustParse(size)}},
+			StorageClassName: storageClassName,
 		},
 	}
 	return pvc
@@ -147,7 +150,7 @@ func TestInitializeArtifactStorageWithConfigMap(t *testing.T) {
 		expectedArtifactStorage ArtifactStorageInterface
 		storagetype             string
 	}{{
-		desc: "pvc configmap",
+		desc: "pvc configmap size",
 		configMap: &corev1.ConfigMap{
 			ObjectMeta: metav1.ObjectMeta{
 				Namespace: system.GetNamespace(),
@@ -160,7 +163,24 @@ func TestInitializeArtifactStorageWithConfigMap(t *testing.T) {
 		pipelinerun: pipelinerun,
 		expectedArtifactStorage: &v1alpha1.ArtifactPVC{
 			Name:                  "pipelineruntest",
-			PersistentVolumeClaim: GetPersistentVolumeClaim("10Gi"),
+			PersistentVolumeClaim: GetPersistentVolumeClaim("10Gi", defaultStorageClass),
+		},
+		storagetype: "pvc",
+	}, {
+		desc: "pvc configmap storageclass",
+		configMap: &corev1.ConfigMap{
+			ObjectMeta: metav1.ObjectMeta{
+				Namespace: system.GetNamespace(),
+				Name:      PvcConfigName,
+			},
+			Data: map[string]string{
+				PvcStorageClassNameKey: customStorageClass,
+			},
+		},
+		pipelinerun: pipelinerun,
+		expectedArtifactStorage: &v1alpha1.ArtifactPVC{
+			Name:                  "pipelineruntest",
+			PersistentVolumeClaim: GetPersistentVolumeClaim("5Gi", &customStorageClass),
 		},
 		storagetype: "pvc",
 	}, {
@@ -341,7 +361,7 @@ func TestCleanupArtifactStorage(t *testing.T) {
 		},
 	}} {
 		t.Run(c.desc, func(t *testing.T) {
-			fakekubeclient := fakek8s.NewSimpleClientset(c.configMap, GetPVCSpec(c.pipelinerun, persistentVolumeClaim.Spec.Resources.Requests["storage"]))
+			fakekubeclient := fakek8s.NewSimpleClientset(c.configMap, GetPVCSpec(c.pipelinerun, persistentVolumeClaim.Spec.Resources.Requests["storage"], defaultStorageClass))
 			_, err := fakekubeclient.CoreV1().PersistentVolumeClaims(c.pipelinerun.Namespace).Get(GetPVCName(c.pipelinerun), metav1.GetOptions{})
 			if err != nil {
 				t.Fatalf("Error getting expected PVC %s for PipelineRun %s: %s", GetPVCName(c.pipelinerun), c.pipelinerun.Name, err)

pkg/artifacts/artifacts_storage.go

@@ -41,6 +41,9 @@ const (
 
 	// DefaultPvcSize is the default size of the PVC to create
 	DefaultPvcSize = "5Gi"
+
+	// PvcStorageClassNameKey is the name of the configmap entry that specifies the storage class of the PVC to create
+	PvcStorageClassNameKey = "storageClassName"
 )
 
 // ArtifactStorageInterface is an interface to define the steps to copy
@@ -163,8 +166,10 @@ func createPVC(pr *v1alpha1.PipelineRun, c kubernetes.Interface) (*corev1.Persis
 				return nil, xerrors.Errorf("failed to get PVC ConfigMap %s for %q due to error: %w", PvcConfigName, pr.Name, err)
 			}
 			var pvcSizeStr string
+			var pvcStorageClassNameStr string
 			if configMap != nil {
 				pvcSizeStr = configMap.Data[PvcSizeKey]
+				pvcStorageClassNameStr = configMap.Data[PvcStorageClassNameKey]
 			}
 			if pvcSizeStr == "" {
 				pvcSizeStr = DefaultPvcSize
@@ -173,7 +178,14 @@ func createPVC(pr *v1alpha1.PipelineRun, c kubernetes.Interface) (*corev1.Persis
 			if err != nil {
 				return nil, xerrors.Errorf("failed to create Persistent Volume spec for %q due to error: %w", pr.Name, err)
 			}
-			pvcSpec := GetPVCSpec(pr, pvcSize)
+			var pvcStorageClassName *string
+			if pvcStorageClassNameStr == "" {
+				pvcStorageClassName = nil
+			} else {
+				pvcStorageClassName = &pvcStorageClassNameStr
+			}
+
+			pvcSpec := GetPVCSpec(pr, pvcSize, pvcStorageClassName)
 			pvc, err := c.CoreV1().PersistentVolumeClaims(pr.Namespace).Create(pvcSpec)
 			if err != nil {
 				return nil, xerrors.Errorf("failed to claim Persistent Volume %q due to error: %w", pr.Name, err)
@@ -197,7 +209,7 @@ func deletePVC(pr *v1alpha1.PipelineRun, c kubernetes.Interface) error {
 }
 
 // GetPVCSpec returns the PVC to create for a given PipelineRun
-func GetPVCSpec(pr *v1alpha1.PipelineRun, pvcSize resource.Quantity) *corev1.PersistentVolumeClaim {
+func GetPVCSpec(pr *v1alpha1.PipelineRun, pvcSize resource.Quantity, storageClassName *string) *corev1.PersistentVolumeClaim {
 	return &corev1.PersistentVolumeClaim{
 		ObjectMeta: metav1.ObjectMeta{
 			Namespace:       pr.Namespace,
@@ -211,6 +223,7 @@ func GetPVCSpec(pr *v1alpha1.PipelineRun, pvcSize resource.Quantity) *corev1.Per
 					corev1.ResourceStorage: pvcSize,
 				},
 			},
+			StorageClassName: storageClassName,
 		},
 	}
 }