Don't provision VM for empty artifacts (#1660)

workflow/controller/workflowpod.go

@@ -702,6 +702,11 @@ func (woc *wfOperationCtx) addInputArtifactsVolumes(pod *apiv1.Pod, tmpl *wfv1.T
  if art.Path == "" {
  return errors.Errorf(errors.CodeBadRequest, "inputs.artifacts.%s did not specify a path", art.Name)
  }
+ if !art.HasLocation() && art.Optional {
+ woc.log.Infof("skip volume mount of %s (%s): optional artifact was not provided",
+ art.Name, art.Path)
+ continue
+ }
  overlap := common.FindOverlappingVolume(tmpl, art.Path)
  if overlap != nil {
  // artifact path overlaps with a mounted volume. do not mount the

workflow/controller/workflowpod_test.go

@@ -77,6 +77,65 @@ func TestScriptTemplateWithVolume(t *testing.T) {
  assert.NoError(t, err)
 }
 
+var scriptTemplateWithOptionalInputArtifactProvided = `
+name: script-with-input-artifact
+inputs:
+ artifacts:
+ - name: manifest
+ path: /manifest
+ optional: true
+ http:
+ url: https://raw.githubusercontent.com/argoproj/argo/stable/manifests/install.yaml
+script:
+ image: alpine:latest
+ command: [sh]
+ source: |
+ ls -al
+`
+
+var scriptTemplateWithOptionalInputArtifactNotProvided = `
+name: script-with-input-artifact
+inputs:
+ artifacts:
+ - name: manifest
+ path: /manifest
+ optional: true
+script:
+ image: alpine:latest
+ command: [sh]
+ source: |
+ ls -al
+`
+// TestScriptTemplateWithVolume ensure we can a script pod with input artifacts
+func TestScriptTemplateWithoutVolumeOptionalArtifact(t *testing.T) {
+ volumeMount := apiv1.VolumeMount{
+ Name: "input-artifacts",
+ ReadOnly: false,
+ MountPath: "/manifest",
+ SubPath: "manifest",
+ MountPropagation: nil,
+ SubPathExpr: "",
+ }
+
+ // Ensure that volume mount is added when artifact is provided
+ tmpl := unmarshalTemplate(scriptTemplateWithOptionalInputArtifactProvided)
+ woc := newWoc()
+ mainCtr := tmpl.Script.Container
+ mainCtr.Args = append(mainCtr.Args, common.ExecutorScriptSourcePath)
+ pod, err := woc.createWorkflowPod(tmpl.Name, mainCtr, tmpl, true)
+ assert.NoError(t, err)
+ assert.Contains(t, pod.Spec.Containers[1].VolumeMounts, volumeMount)
+
+ // Ensure that volume mount is not created when artifact is not provided
+ tmpl = unmarshalTemplate(scriptTemplateWithOptionalInputArtifactNotProvided)
+ woc = newWoc()
+ mainCtr = tmpl.Script.Container
+ mainCtr.Args = append(mainCtr.Args, common.ExecutorScriptSourcePath)
+ pod, err = woc.createWorkflowPod(tmpl.Name, mainCtr, tmpl, true)
+ assert.NoError(t, err)
+ assert.NotContains(t, pod.Spec.Containers[1].VolumeMounts, volumeMount)
+}
+
 // TestWFLevelServiceAccount verifies the ability to carry forward the service account name
 // for the pod from workflow.spec.serviceAccountName.
 func TestWFLevelServiceAccount(t *testing.T) {