fix: retry node with expression status Running -> Pending (argoproj#1…

…2637)

Signed-off-by: shuangkun <[email protected]>

workflow/controller/operator.go

@@ -960,7 +960,7 @@ func (woc *wfOperationCtx) processNodeRetries(node *wfv1.NodeStatus, retryStrate
 		if err != nil {
 			return nil, false, err
 		}
-		if !shouldContinue {
+		if !shouldContinue && lastChildNode.Fulfilled() {
 			return woc.markNodePhase(node.Name, lastChildNode.Phase, "retryStrategy.expression evaluated to false"), true, nil
 		}
 	}

workflow/controller/operator_test.go

@@ -876,6 +876,86 @@ func TestProcessNodeRetriesWithExponentialBackoff(t *testing.T) {
 	require.Equal(wfv1.NodeSucceeded, n.Phase)
 }
 
+// TestProcessNodeRetries tests retrying with Expression
+func TestProcessNodeRetriesWithExpression(t *testing.T) {
+	cancel, controller := newController()
+	defer cancel()
+	assert.NotNil(t, controller)
+	wf := wfv1.MustUnmarshalWorkflow(helloWorldWf)
+	assert.NotNil(t, wf)
+	woc := newWorkflowOperationCtx(wf, controller)
+	assert.NotNil(t, woc)
+	// Verify that there are no nodes in the wf status.
+	assert.Zero(t, len(woc.wf.Status.Nodes))
+
+	// Add the parent node for retries.
+	nodeName := "test-node"
+	nodeID := woc.wf.NodeID(nodeName)
+	node := woc.initializeNode(nodeName, wfv1.NodeTypeRetry, "", &wfv1.WorkflowStep{}, "", wfv1.NodeRunning, &wfv1.NodeFlag{})
+	retries := wfv1.RetryStrategy{}
+	retries.Expression = "false"
+	retries.Limit = intstrutil.ParsePtr("2")
+	retries.RetryPolicy = wfv1.RetryPolicyAlways
+	woc.wf.Status.Nodes[nodeID] = *node
+
+	assert.Equal(t, node.Phase, wfv1.NodeRunning)
+
+	// Ensure there are no child nodes yet.
+	lastChild := getChildNodeIndex(node, woc.wf.Status.Nodes, -1)
+	assert.Nil(t, lastChild)
+
+	// Add child nodes.
+	for i := 0; i < 2; i++ {
+		childNode := fmt.Sprintf("%s(%d)", nodeName, i)
+		woc.initializeNode(childNode, wfv1.NodeTypePod, "", &wfv1.WorkflowStep{}, "", wfv1.NodeRunning, &wfv1.NodeFlag{Retried: true})
+		woc.addChildNode(nodeName, childNode)
+	}
+
+	n, err := woc.wf.GetNodeByName(nodeName)
+	assert.NoError(t, err)
+	lastChild = getChildNodeIndex(n, woc.wf.Status.Nodes, -1)
+	assert.NotNil(t, lastChild)
+
+	// Last child is still running. processNodeRetries() should return false since
+	// there should be no retries at this point.
+	n, _, err = woc.processNodeRetries(n, retries, &executeTemplateOpts{})
+	assert.NoError(t, err)
+	assert.Equal(t, n.Phase, wfv1.NodeRunning)
+
+	// Mark lastChild Pending.
+	woc.markNodePhase(lastChild.Name, wfv1.NodePending)
+	n, _, err = woc.processNodeRetries(n, retries, &executeTemplateOpts{})
+	assert.Nil(t, err)
+	assert.Equal(t, n.Phase, wfv1.NodeRunning)
+
+	// Mark lastChild as successful.
+	woc.markNodePhase(lastChild.Name, wfv1.NodeSucceeded)
+	n, _, err = woc.processNodeRetries(n, retries, &executeTemplateOpts{})
+	assert.Nil(t, err)
+	// The parent node also gets marked as Succeeded.
+	assert.Equal(t, n.Phase, wfv1.NodeSucceeded)
+
+	// Mark the parent node as running again and the lastChild as errored.
+	n = woc.markNodePhase(n.Name, wfv1.NodeRunning)
+	woc.markNodePhase(lastChild.Name, wfv1.NodeError)
+	_, _, err = woc.processNodeRetries(n, retries, &executeTemplateOpts{})
+	assert.NoError(t, err)
+	n, err = woc.wf.GetNodeByName(nodeName)
+	assert.NoError(t, err)
+	assert.Equal(t, n.Phase, wfv1.NodeError)
+
+	// Add a third node that has failed.
+	woc.markNodePhase(n.Name, wfv1.NodeRunning)
+	childNode := fmt.Sprintf("%s(%d)", nodeName, 3)
+	woc.initializeNode(childNode, wfv1.NodeTypePod, "", &wfv1.WorkflowStep{}, "", wfv1.NodeFailed, &wfv1.NodeFlag{Retried: true})
+	woc.addChildNode(nodeName, childNode)
+	n, err = woc.wf.GetNodeByName(nodeName)
+	assert.NoError(t, err)
+	n, _, err = woc.processNodeRetries(n, retries, &executeTemplateOpts{})
+	assert.NoError(t, err)
+	assert.Equal(t, n.Phase, wfv1.NodeFailed)
+}
+
 func parseRetryMessage(message string) (int, error) {
 	pattern := regexp.MustCompile(`Backoff for (\d+) minutes (\d+) seconds`)
 	matches := pattern.FindStringSubmatch(message)