Fix taskrun not working with workspace having volumeClaimTemplate

This will move the auto name generation of workspace to happen after
the pvc is created for volumeClaimTemplate and then name will be generated for
workspace of volumeClaimTemplate type

Added an example

Fix tektoncd#5537

examples/v1beta1/taskruns/workspace-with-volumeClaimTemplate.yaml

@@ -0,0 +1,24 @@
+apiVersion: tekton.dev/v1beta1
+kind: TaskRun
+metadata:
+  generateName: task-with-workspace-run-
+spec:
+  taskSpec:
+    steps:
+      - name: list-files
+        image: ubuntu
+        script: ls $(workspaces.read-allowed.path)
+    workspaces:
+      - name: read-allowed
+  workspaces:
+    - name: read-allowed
+      volumeClaimTemplate:
+        metadata:
+          name: pvc
+        spec:
+          accessModes:
+            - ReadWriteOnce
+          resources:
+            requests:
+              storage: 1Gi
+          volumeMode: Filesystem

pkg/reconciler/taskrun/taskrun.go

@@ -448,16 +448,6 @@ func (c *Reconciler) reconcile(ctx context.Context, tr *v1beta1.TaskRun, rtr *re
 	recorder := controller.GetEventRecorder(ctx)
 	var err error
 
-	// Get the randomized volume names assigned to workspace bindings
-	workspaceVolumes := workspace.CreateVolumes(tr.Spec.Workspaces)
-
-	ts, err := applyParamsContextsResultsAndWorkspaces(ctx, tr, rtr, workspaceVolumes)
-	if err != nil {
-		logger.Errorf("Error updating task spec parameters, contexts, results and workspaces: %s", err)
-		return err
-	}
-	tr.Status.TaskSpec = ts
-
 	// Get the TaskRun's Pod if it should have one. Otherwise, create the Pod.
 	var pod *corev1.Pod
 
@@ -505,6 +495,17 @@ func (c *Reconciler) reconcile(ctx context.Context, tr *v1beta1.TaskRun, rtr *re
 			// This is used by createPod below. Changes to the Spec are not updated.
 			tr.Spec.Workspaces = taskRunWorkspaces
 		}
+
+		// Get the randomized volume names assigned to workspace bindings
+		workspaceVolumes := workspace.CreateVolumes(tr.Spec.Workspaces)
+
+		ts, err := applyParamsContextsResultsAndWorkspaces(ctx, tr, rtr, workspaceVolumes)
+		if err != nil {
+			logger.Errorf("Error updating task spec parameters, contexts, results and workspaces: %s", err)
+			return err
+		}
+		tr.Status.TaskSpec = ts
+
 		pod, err = c.createPod(ctx, ts, tr, rtr, workspaceVolumes)
 		if err != nil {
 			newErr := c.handlePodCreationError(tr, err)