fix: Fix bugs, unable to resolve tasks aggregated outputs in dag outputs. Fixes #6684

workflow/controller/dag.go

@@ -276,7 +276,19 @@ func (woc *wfOperationCtx) executeDAG(ctx context.Context, nodeName string, tmpl
 			// Can happen when dag.target was specified
 			continue
 		}
-		woc.buildLocalScope(scope, fmt.Sprintf("tasks.%s", task.Name), taskNode)
+
+		prefix := fmt.Sprintf("tasks.%s", task.Name)
+		if taskNode.Type == wfv1.NodeTypeTaskGroup {
+			childNodes := make([]wfv1.NodeStatus, len(taskNode.Children))
+			for i, childID := range taskNode.Children {
+				childNodes[i] = woc.wf.Status.Nodes[childID]
+			}
+			err := woc.processAggregateNodeOutputs(scope, prefix, childNodes)
+			if err != nil {
+				return nil, errors.InternalWrapError(err)
+			}
+		}
+		woc.buildLocalScope(scope, prefix, taskNode)
 		woc.addOutputsToGlobalScope(taskNode.Outputs)
 	}
 	outputs, err := getTemplateOutputsFromScope(tmpl, scope)

workflow/controller/dag_test.go

@@ -3150,3 +3150,174 @@ func TestLeafContinueOn(t *testing.T) {
 	woc.operate(ctx)
 	assert.Equal(t, wfv1.WorkflowSucceeded, woc.wf.Status.Phase)
 }
+
+var dagOutputsReferTaskAggregatedOuputs = `
+apiVersion: argoproj.io/v1alpha1
+kind: Workflow
+metadata:
+  name: parameter-aggregation-dag-h8b82
+spec:
+
+  entrypoint: parameter-aggregation
+  templates:
+  -
+    dag:
+      tasks:
+      - arguments:
+          parameters:
+          - name: num
+            value: '{{item}}'
+        name: odd-or-even
+        template: odd-or-even
+        withItems:
+        - 1
+        - 2
+    inputs: {}
+    metadata: {}
+    name: parameter-aggregation
+    outputs:
+      parameters:
+      - name: dag-nums
+        valueFrom:
+          parameter: '{{tasks.odd-or-even.outputs.parameters.num}}'
+      - name: dag-evenness
+        valueFrom:
+          parameter: '{{tasks.odd-or-even.outputs.parameters.evenness}}'
+  -
+    container:
+      args:
+      - |
+        sleep 1 &&
+        echo {{inputs.parameters.num}} > /tmp/num &&
+        if [ $(({{inputs.parameters.num}}%2)) -eq 0 ]; then
+          echo "even" > /tmp/even;
+        else
+          echo "odd" > /tmp/even;
+        fi
+      command:
+      - sh
+      - -c
+      image: alpine:latest
+      name: ""
+      resources: {}
+    inputs:
+      parameters:
+      - name: num
+    metadata: {}
+    name: odd-or-even
+    outputs:
+      parameters:
+      - name: num
+        valueFrom:
+          path: /tmp/num
+      - name: evenness
+        valueFrom:
+          path: /tmp/even
+status:
+  nodes:
+    parameter-aggregation-dag-h8b82:
+      children:
+      - parameter-aggregation-dag-h8b82-3379492521
+      displayName: parameter-aggregation-dag-h8b82
+      finishedAt: "2020-12-09T15:37:07Z"
+      id: parameter-aggregation-dag-h8b82
+      name: parameter-aggregation-dag-h8b82
+      outboundNodes:
+      - parameter-aggregation-dag-h8b82-3175470584
+      - parameter-aggregation-dag-h8b82-2243926302
+      phase: Running
+      startedAt: "2020-12-09T15:36:46Z"
+      templateName: parameter-aggregation
+      templateScope: local/parameter-aggregation-dag-h8b82
+      type: DAG
+    parameter-aggregation-dag-h8b82-1440345089:
+      boundaryID: parameter-aggregation-dag-h8b82
+      displayName: odd-or-even(1:2)
+      finishedAt: "2020-12-09T15:36:54Z"
+      hostNodeName: minikube
+      id: parameter-aggregation-dag-h8b82-1440345089
+      inputs:
+        parameters:
+        - name: num
+          value: "2"
+      name: parameter-aggregation-dag-h8b82.odd-or-even(1:2)
+      outputs:
+        exitCode: "0"
+        parameters:
+        - name: num
+          value: "2"
+          valueFrom:
+            path: /tmp/num
+        - name: evenness
+          value: even
+          valueFrom:
+            path: /tmp/even
+      phase: Succeeded
+      startedAt: "2020-12-09T15:36:46Z"
+      templateName: odd-or-even
+      templateScope: local/parameter-aggregation-dag-h8b82
+      type: Pod
+    parameter-aggregation-dag-h8b82-3379492521:
+      boundaryID: parameter-aggregation-dag-h8b82
+      children:
+      - parameter-aggregation-dag-h8b82-3572919299
+      - parameter-aggregation-dag-h8b82-1440345089
+      displayName: odd-or-even
+      finishedAt: "2020-12-09T15:36:55Z"
+      id: parameter-aggregation-dag-h8b82-3379492521
+      name: parameter-aggregation-dag-h8b82.odd-or-even
+      phase: Succeeded
+      startedAt: "2020-12-09T15:36:46Z"
+      templateName: odd-or-even
+      templateScope: local/parameter-aggregation-dag-h8b82
+      type: TaskGroup
+    parameter-aggregation-dag-h8b82-3572919299:
+      boundaryID: parameter-aggregation-dag-h8b82
+      displayName: odd-or-even(0:1)
+      finishedAt: "2020-12-09T15:36:53Z"
+      hostNodeName: minikube
+      id: parameter-aggregation-dag-h8b82-3572919299
+      inputs:
+        parameters:
+        - name: num
+          value: "1"
+      name: parameter-aggregation-dag-h8b82.odd-or-even(0:1)
+      outputs:
+        exitCode: "0"
+        parameters:
+        - name: num
+          value: "1"
+          valueFrom:
+            path: /tmp/num
+        - name: evenness
+          value: odd
+          valueFrom:
+            path: /tmp/even
+      phase: Succeeded
+      startedAt: "2020-12-09T15:36:46Z"
+      templateName: odd-or-even
+      templateScope: local/parameter-aggregation-dag-h8b82
+      type: Pod
+  phase: Succeeded
+  startedAt: "2020-12-09T15:36:46Z"
+`
+
+func TestDAGReferTaskAggregatedOutputs(t *testing.T) {
+	wf := wfv1.MustUnmarshalWorkflow(dagOutputsReferTaskAggregatedOuputs)
+	cancel, controller := newController(wf)
+	defer cancel()
+
+	ctx := context.Background()
+	woc := newWorkflowOperationCtx(wf, controller)
+	woc.operate(ctx)
+
+	dagNode := woc.wf.Status.Nodes.FindByDisplayName("parameter-aggregation-dag-h8b82")
+	if assert.NotNil(t, dagNode) {
+		if assert.NotNil(t, dagNode.Outputs) {
+			if assert.Len(t, dagNode.Outputs.Parameters, 2) {
+				assert.Equal(t, `["1","2"]`, dagNode.Outputs.Parameters[0].Value.String())
+				assert.Equal(t, `["odd","even"]`, dagNode.Outputs.Parameters[1].Value.String())
+			}
+		}
+	}
+}

workflow/validate/validate.go

@@ -1199,7 +1199,8 @@ func (ctx *templateValidationCtx) validateDAG(scope map[string]interface{}, tmpl
 		resolvedTemplates[task.Name] = resolvedTmpl
 
 		prefix := fmt.Sprintf("tasks.%s", task.Name)
-		ctx.addOutputsToScope(resolvedTmpl, prefix, scope, false, false)
+		aggregate := len(task.WithItems) > 0 || task.WithParam != ""
+		ctx.addOutputsToScope(resolvedTmpl, prefix, scope, aggregate, false)
 
 		err = common.ValidateTaskResults(&task)
 		if err != nil {

workflow/validate/validate_dag_test.go

@@ -943,3 +943,93 @@ func TestDAGWithDigitNameNoDepends(t *testing.T) {
 	_, err := validate(dagWithDigitNoDepends)
 	assert.NoError(t, err)
 }
+
+var dagOutputsResolveTaskAggregatedOutputs = `
+apiVersion: argoproj.io/v1alpha1
+kind: Workflow
+metadata:
+  generateName: loops-
+spec:
+  serviceAccountName: argo
+  entrypoint: dag
+  templates:
+  - name: dag
+    dag:
+      tasks:
+      - name: fanout
+        template: fanout
+        arguments:
+          parameters:
+          - name: input
+            value: "[1, 2]"
+      - name: dag-process
+        template: sub-dag
+        depends: fanout
+        arguments:
+          parameters:
+          - name: item
+            value: '{{item}}'
+          - name: input
+            value: '{{tasks.fanout.outputs.parameters.output}}'
+        withParam: "{{tasks.fanout.outputs.parameters.output}}"
+
+  - name: sub-dag
+    inputs:
+      parameters:
+      - name: input
+      - name: item
+    outputs:
+      parameters:
+      - name: output
+        valueFrom:
+          parameter: "{{tasks.process.outputs.parameters}}"
+    dag:
+      tasks:
+      - name: fanout
+        template: fanout
+        arguments:
+          parameters:
+          - name: input
+            value: '{{inputs.parameters.input}}'
+      - name: process
+        template: process
+        depends: fanout
+        arguments:
+          parameters:
+          - name: item
+            value: '{{item}}'
+        withParam: "{{tasks.fanout.outputs.parameters.output}}"
+
+  - name: fanout
+    inputs:
+      parameters:
+      - name: input
+    container:
+      image: docker/whalesay:latest
+      command: [sh, -c]
+      args: ["echo {{inputs.parameters.input}} | tee /tmp/output"]
+    outputs:
+      parameters:
+      - name: output
+        valueFrom:
+          path: /tmp/output
+
+  - name: process
+    inputs:
+      parameters:
+      - name: item
+    container:
+      image: docker/whalesay:latest
+      command: [sh, -c]
+      args: ["echo {{inputs.parameters.item}} | tee /tmp/output"]
+    outputs:
+      parameters:
+      - name: output
+        valueFrom:
+          path: /tmp/output
+`
+
+func TestDAGOutputsResolveTaskAggregatedOutputs(t *testing.T) {
+	_, err := validate(dagOutputsResolveTaskAggregatedOutputs)
+	assert.NoError(t, err)
+}