feat: add finalizer to workflow pod to prevent "pod deleted"

Signed-off-by: Rohan Kumar <rohankmr414@gmail.com>

workflow/common/common.go

@@ -223,6 +223,8 @@ const (
 	ErrDeadlineExceeded = "DeadlineExceeded"
 
 	ConfigMapName = "workflow-controller-configmap"
+
+	WorkflowFinalizer = "argoproj.io/workflow-finalizer"
 )
 
 // AnnotationKeyKillCmd specifies the command to use to kill to container, useful for injected sidecars

workflow/controller/controller.go

@@ -490,15 +490,26 @@ func (wfc *WorkflowController) processNextPodCleanupItem(ctx context.Context) bo
 				ctx,
 				podName,
 				types.MergePatchType,
-				[]byte(`{"metadata": {"labels": {"workflows.argoproj.io/completed": "true"}}}`),
+				[]byte(`{"metadata": {"labels": {"workflows.argoproj.io/completed": "true"}, "finalizers": []}}`),
 				metav1.PatchOptions{},
 			)
 			if err != nil {
 				return err
 			}
 		case deletePod:
+			// remove the finalizer to allow the pod to be deleted
+			_, err := pods.Patch(
+				ctx,
+				podName,
+				types.MergePatchType,
+				[]byte(`{"metadata": {"finalizers": []}}`),
+				metav1.PatchOptions{},
+			)
+			if err != nil {
+				return err
+			}
 			propagation := metav1.DeletePropagationBackground
-			err := pods.Delete(ctx, podName, metav1.DeleteOptions{
+			err = pods.Delete(ctx, podName, metav1.DeleteOptions{
 				PropagationPolicy:  &propagation,
 				GracePeriodSeconds: wfc.Config.PodGCGracePeriodSeconds,
 			})

workflow/controller/workflowpod.go

@@ -172,6 +172,7 @@ func (woc *wfOperationCtx) createWorkflowPod(ctx context.Context, nodeName strin
 			OwnerReferences: []metav1.OwnerReference{
 				*metav1.NewControllerRef(woc.wf, wfv1.SchemeGroupVersion.WithKind(workflow.WorkflowKind)),
 			},
+			Finalizers: []string{common.WorkflowFinalizer},
 		},
 		Spec: apiv1.PodSpec{
 			RestartPolicy:         apiv1.RestartPolicyNever,