fix: allow labelsFrom to be specified in workflowDefaults. Fixes #14927 (cherry-pick #14941 for 3.7)

workflow/util/merge.go

@@ -16,11 +16,20 @@ func MergeTo(patch, target *wfv1.Workflow) error {
 		return nil
 	}
 
+	// Temporarily remove hooks and labelsFrom as they don't merge
 	patchHooks := patch.Spec.Hooks
-	// Temporarily remove hooks as they don't merge
 	patch.Spec.Hooks = nil
+	var patchLabelsFrom map[string]wfv1.LabelValueFrom
+	if patch.Spec.WorkflowMetadata != nil {
+		patchLabelsFrom = patch.Spec.WorkflowMetadata.LabelsFrom
+		patch.Spec.WorkflowMetadata.LabelsFrom = nil
+	}
+
 	patchWfBytes, err := json.Marshal(patch)
 	patch.Spec.Hooks = patchHooks
+	if len(patchLabelsFrom) != 0 {
+		patch.Spec.WorkflowMetadata.LabelsFrom = patchLabelsFrom
+	}
 	if err != nil {
 		return err
 	}
@@ -52,6 +61,16 @@ func MergeTo(patch, target *wfv1.Workflow) error {
 			target.Spec.Hooks[name] = hook
 		}
 	}
+
+	if len(patchLabelsFrom) != 0 && target.Spec.WorkflowMetadata.LabelsFrom == nil {
+		target.Spec.WorkflowMetadata.LabelsFrom = make(map[string]wfv1.LabelValueFrom)
+	}
+	for key, val := range patchLabelsFrom {
+		// If the patch labelFrom doesn't exist in target
+		if _, ok := target.Spec.WorkflowMetadata.LabelsFrom[key]; !ok {
+			target.Spec.WorkflowMetadata.LabelsFrom[key] = val
+		}
+	}
 	return nil
 }
 

workflow/util/merge_test.go

@@ -429,7 +429,7 @@ func TestJoinWorkflowMetaData(t *testing.T) {
 	})
 }
 
-var baseNilHookWF = `
+var baseNilWF = `
 apiVersion: argoproj.io/v1alpha1
 kind: Workflow
 metadata:
@@ -471,7 +471,7 @@ spec:
 func TestMergeHooks(t *testing.T) {
 	t.Run("NilBaseAndNilPatch", func(t *testing.T) {
 		patchHookWf := wfv1.MustUnmarshalWorkflow(patchNilHookWF)
-		targetHookWf := wfv1.MustUnmarshalWorkflow(baseNilHookWF)
+		targetHookWf := wfv1.MustUnmarshalWorkflow(baseNilWF)
 
 		err := MergeTo(patchHookWf, targetHookWf)
 		require.NoError(t, err)
@@ -480,7 +480,7 @@ func TestMergeHooks(t *testing.T) {
 
 	t.Run("NilBaseAndNotNilPatch", func(t *testing.T) {
 		patchHookWf := wfv1.MustUnmarshalWorkflow(patchHookWF)
-		targetHookWf := wfv1.MustUnmarshalWorkflow(baseNilHookWF)
+		targetHookWf := wfv1.MustUnmarshalWorkflow(baseNilWF)
 
 		err := MergeTo(patchHookWf, targetHookWf)
 		require.NoError(t, err)
@@ -501,3 +501,51 @@ func TestMergeHooks(t *testing.T) {
 		assert.Equal(t, "b", targetHookWf.Spec.Hooks[`bar`].Template)
 	})
 }
+
+var patchLabelsFromWF = `
+apiVersion: argoproj.io/v1alpha1
+kind: Workflow
+spec:
+  workflowMetadata:
+    labelsFrom:
+      foo:
+        expression: PATCH
+      bar:
+        expression: PATCH
+`
+var baseLabelsFromWF = `
+apiVersion: argoproj.io/v1alpha1
+kind: Workflow
+spec:
+  workflowMetadata:
+    labelsFrom:
+      foo:
+        expression: BASE
+      baz:
+        expression: BASE
+`
+
+func TestMergeLabelsFrom(t *testing.T) {
+	t.Run("NilBaseAndNotNilPatch", func(t *testing.T) {
+		patchWf := wfv1.MustUnmarshalWorkflow(patchLabelsFromWF)
+		targetWf := wfv1.MustUnmarshalWorkflow(baseNilWF)
+
+		err := MergeTo(patchWf, targetWf)
+		require.NoError(t, err)
+		assert.Len(t, targetWf.Spec.WorkflowMetadata.LabelsFrom, 2)
+		assert.Equal(t, "PATCH", targetWf.Spec.WorkflowMetadata.LabelsFrom[`foo`].Expression)
+		assert.Equal(t, "PATCH", targetWf.Spec.WorkflowMetadata.LabelsFrom[`bar`].Expression)
+	})
+
+	t.Run("NotNilBaseAndPatch", func(t *testing.T) {
+		patchWf := wfv1.MustUnmarshalWorkflow(patchLabelsFromWF)
+		targetWf := wfv1.MustUnmarshalWorkflow(baseLabelsFromWF)
+
+		err := MergeTo(patchWf, targetWf)
+		require.NoError(t, err)
+		assert.Len(t, targetWf.Spec.WorkflowMetadata.LabelsFrom, 3)
+		assert.Equal(t, "BASE", targetWf.Spec.WorkflowMetadata.LabelsFrom[`foo`].Expression)
+		assert.Equal(t, "PATCH", targetWf.Spec.WorkflowMetadata.LabelsFrom[`bar`].Expression)
+		assert.Equal(t, "BASE", targetWf.Spec.WorkflowMetadata.LabelsFrom[`baz`].Expression)
+	})
+}