Can a WorkflowTemplate reference another WorkflowTemplate?

[almirmcunhajr]

I’ve tried to create a WorkflowTemplate that references another WorkflowTemplate, but it doesn’t seem to work. When I submit it, It fails requiring me to provide an entrypoint. However, the cd WorkflowTemplate has an entrypoint configured.

apiVersion: argoproj.io/v1alpha1
kind: WorkflowTemplate
metadata:
  name: actions-playground-cd
spec:
  workflowTemplateRef:
    name: cd
  arguments:
    parameters:
      - name: slack-channel
        value: ""

[jorgelon]

can you paste the cd workflowtemplate?

[Joibel]

WorkflowTemplateRef only actually works from a Workflow or CronWorkflow as far as I know.

https://github.com/argoproj/argo-workflows/blob/main/docs/fields.md doesn't actually state this.

[almirmcunhajr]

Do you have any suggestions on how to reuse a WorkflowTemplate within another WorkflowTemplate? I prefer not to refer directly to a template within the WorkflowTemplate because I want to reuse specific workflow-level configurations, such as the exit handler. Additionally, I cannot grant the actions-playground-cd's service account permission to create Kubernetes resources, which means I can't create a Workflow resource that references the CD WorkflowTemplate.

[wesleyscholl]

@almirmcunhajr

workflowTemplateRef only accepts the following fields:

Field Name	Field Type	Description
clusterScope	boolean	Indicates the referred template is cluster scoped (i.e., a ClusterWorkflowTemplate).
name	string	The resource name of the workflow template.

However, templateRef can be used within steps or a dag to reference another WorkflowTemplate, specify the entrypoint and pass parameters.

Updated version of your WorkflowTemplate

apiVersion: argoproj.io/v1alpha1
kind: WorkflowTemplate
metadata:
  name: actions-playground-cd
spec:
  entrypoint: main
  templates:
  - name: main
    steps:
      - - name: cd-step
          templateRef:
            name: cd # Other WorkflowTemplate name
            template: main # Other WorkflowTemplate entrypoint
          arguments:
            parameters:
            - name: slack-channel
              value: ""

Other WorkflowTemplate to call

apiVersion: argoproj.io/v1alpha1
kind: WorkflowTemplate
metadata:
  name: cd
spec:
  entrypoint: main
  arguments:
    parameters:
    - name: slack-channel
      value: ""
  templates:
  - name: main
    inputs:
      parameters:
      - name: slack-channel
    container:
      image: busybox
      command: [echo]
      args: ["{{inputs.parameters.slack-channel}}"] 

Resources

• https://argo-workflows.readthedocs.io/en/latest/workflow-templates/#referencing-other-workflowtemplates
• https://argo-workflows.readthedocs.io/en/latest/fields/#templateref
• https://github.com/argoproj/argo-workflows/blob/main/examples/workflow-template/hello-world.yaml
• https://argo-workflows.readthedocs.io/en/latest/fields/#workflowtemplateref

[sstaley-hioscar]

Considering that some teams set templateReferencing: Strict it's frustrating that this isn't a feature. I'm essentially unable to share a cluster workflow for usage in any namespace without using a subtemplate of the workflow. Wish I had time to look into this myself.