parameter-aggregation-script.yaml

# Example workflow to demonstrate parameter aggregation.
apiVersion: argoproj.io/v1alpha1
kind: Workflow
metadata:
  generateName: parameter-aggregation-script-
spec:
  entrypoint: parameter-aggregation
  templates:
  - name: parameter-aggregation
    steps:
    - - name: odd-or-even
        template: odd-or-even
        arguments:
          parameters:
          - name: num
            value: "{{item}}"
        withItems: [1, 2, 3, 4]
    - - name: divide-by-2
        template: divide-by-2
        arguments:
          parameters:
          - name: num
            value: "{{item.num}}"
        withParam: "{{steps.odd-or-even.outputs.result}}"
        when: "{{item.evenness}} == even"

  # odd-or-even accepts a number and returns whether or not that number is odd or even
  - name: odd-or-even
    inputs:
      parameters:
      - name: num
    script:
      image: python:alpine3.6
      command: [python]
      source: |
        import json
        i = {{inputs.parameters.num}}
        res = {
          "num": i,
          "evenness": "even" if i % 2 == 0 else "odd"
        }
        print(json.dumps(res))

  # divide-by-2 divides a number in half
  - name: divide-by-2
    inputs:
      parameters:
      - name: num
    script:
      image: alpine:latest
      command: [sh, -x]
      source: |
        echo $(({{inputs.parameters.num}}/2))