Allow omitting metadata in volumeclaimtemplate

Workspaces can be backed by a PVC that is created from a user provied template, e.g.

    workspaces:
      - name: ws
        volumeClaimTemplate:
          metadata:
            name: ws-pvc
          spec:
            accessModes: ["ReadWriteOnce"]
            resources:
               requests:
                  storage: 1Gi

 but this might fail if the user did not provide a `metadata.name` on the
 template, since the PVC name would be `-<ws-name>-<run-name>` and names
 starting with a `-` is not allowed for PVCs.

 This commits omit the first `-` in the PVC name, if the user did not
 provide a name or metadata part of the volumeclaimtemplate.

 I also added license banners to the two pvc-related go files.

 Fixes #2450

pkg/reconciler/volumeclaim/pvchandler.go

@@ -1,3 +1,19 @@
+/*
+Copyright 2020 The Tekton 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 volumeclaim
 
 import (
@@ -74,5 +90,8 @@ func getPersistentVolumeClaims(workspaceBindings []v1alpha1.WorkspaceBinding, ow
 // GetPersistentVolumeClaimName gets the name of PersistentVolumeClaim for a Workspace and PipelineRun or TaskRun. claim
 // must be a PersistentVolumeClaim from set's VolumeClaims template.
 func GetPersistentVolumeClaimName(claim *corev1.PersistentVolumeClaim, wb v1alpha1.WorkspaceBinding, owner metav1.OwnerReference) string {
+	if claim.Name == "" {
+		return fmt.Sprintf("%s-%s", wb.Name, owner.Name)
+	}
 	return fmt.Sprintf("%s-%s-%s", claim.Name, wb.Name, owner.Name)
 }

pkg/reconciler/volumeclaim/pvchandler_test.go

@@ -1,3 +1,19 @@
+/*
+Copyright 2020 The Tekton 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 volumeclaim
 
 import (
@@ -94,3 +110,44 @@ func TestCreatePersistentVolumeClaimsForWorkspaces(t *testing.T) {
 		t.Fatalf("unexptected name in ownerreference on created PVC; expected: %s got %s", ownerName, pvc.OwnerReferences[0].Name)
 	}
 }
+
+// TestCreatePersistentVolumeClaimsForWorkspacesWithoutMetadata tests that given a volumeClaimTemplate workspace
+// without a metadata part, a PVC is created, with the expected name.
+func TestCreatePersistentVolumeClaimsForWorkspacesWithoutMetadata(t *testing.T) {
+
+	// given
+
+	// workspace with volumeClaimTemplate without metadata
+	workspaceName := "ws-with-volume-claim-template-without-metadata"
+	ownerName := "taskrun1"
+	workspaces := []v1alpha1.WorkspaceBinding{{
+		Name: workspaceName,
+		VolumeClaimTemplate: &corev1.PersistentVolumeClaim{
+			Spec: corev1.PersistentVolumeClaimSpec{},
+		},
+	}}
+
+	ownerRef := metav1.OwnerReference{Name: ownerName}
+	namespace := "ns"
+	fakekubeclient := fakek8s.NewSimpleClientset()
+	pvcHandler := defaultPVCHandler{fakekubeclient, zap.NewExample().Sugar()}
+
+	// when
+
+	err := pvcHandler.CreatePersistentVolumeClaimsForWorkspaces(workspaces, ownerRef, namespace)
+	if err != nil {
+		t.Fatalf("unexpexted error: %v", err)
+	}
+
+	expectedPVCName := fmt.Sprintf("%s-%s", workspaceName, ownerName)
+	pvc, err := fakekubeclient.CoreV1().PersistentVolumeClaims(namespace).Get(expectedPVCName, metav1.GetOptions{})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	// that
+
+	if pvc.Name != expectedPVCName {
+		t.Fatalf("unexpected PVC name on created PVC; exptected: %s got: %s", expectedPVCName, pvc.Name)
+	}
+}