default not respected in configMapKeyRef when used to set global parameters

[phlax]

Pre-requisites

• I have double-checked my configuration
• I can confirm the issues exists when I tested with :latest
• I'd like to contribute the fix myself (see contributing guide)

What happened/what you expected to happen?

Allowing a default value for a ConfigMapKeyRef was added in #8271 (ref #8262)

It does not appear that this works for global workflow parameters

argo-workflows/workflow/controller/operator.go

Lines 578 to 584 in 2f5e753

	if param.ValueFrom != nil && param.ValueFrom.ConfigMapKeyRef != nil {
	cmValue, err := common.GetConfigMapValue(woc.controller.configMapInformer, woc.wf.ObjectMeta.Namespace, param.ValueFrom.ConfigMapKeyRef.Name, param.ValueFrom.ConfigMapKeyRef.Key)
	if err != nil {
	return fmt.Errorf("failed to set global parameter %s from configmap with name %s and key %s: %w",
	param.Name, param.ValueFrom.ConfigMapKeyRef.Name, param.ValueFrom.ConfigMapKeyRef.Key, err)
	}
	woc.globalParams["workflow.parameters."+param.Name] = cmValue

Version

latest

Paste a small workflow that reproduces the issue. We must be able to run the workflow; don't enter a workflows that uses private images.

apiVersion: argoproj.io/v1alpha1
kind: Workflow                                                                                                                                                                
metadata:                                                                                                                                                                     
  generateName: global-cm-param-default-                                                                                                                           
spec:                                                                                                                                                                         
  entrypoint: main                                                                                                                                                            
  arguments:                                                                                                                                                                  
    parameters:                                                                                                                                                                                                                                                                                                              
    - name: param-that-wants-a-default                                                                                                                                                        
      valueFrom:                                                                                                                                                              
        default: ""                                                                                                                                                           
        configMapKeyRef:                                                                                                                                                      
          name: "some-config-map"                                                                                                                           
          key: maybe-existing-key                                                                                                                                                     

      workflowTemplateRef:                                                                                                                                                        
        name: some-wf-template

Logs from the workflow controller

kubectl logs -n argo deploy/workflow-controller | grep ${workflow}

N/A

Logs from in your workflow's wait container

kubectl logs -n argo -c wait -l workflows.argoproj.io/workflow=${workflow},workflow.argoproj.io/phase!=Succeeded

N/A

[sarabala1979]

@phlax Do you like to fix this issue?

[phlax]

i would like to but my go-fu is weak so probably im not best placed to