nested-workflow.yaml

# This example demonstrates the ability to pass and return
# parameters and artifacts into and out of nested workflows
apiVersion: argoproj.io/v1alpha1
kind: Workflow
metadata:
  generateName: nested-workflow-
spec:
  entrypoint: nested-workflow-example
  templates:
  - name: nested-workflow-example
    steps:
    - - name: generate
        template: generate
    - - name: nested-wf
        template: nested-wf
        arguments:
          parameters:
          - name: nested-in-parameter
            value: "{{steps.generate.outputs.parameters.out-parameter}}"
          artifacts:
          - name: nested-in-artifact
            from: "{{steps.generate.outputs.artifacts.out-artifact}}"
    - - name: consume
        template: consume
        arguments:
          parameters:
          - name: in-parameter
            value: "{{steps.nested-wf.outputs.parameters.nested-out-parameter}}"
          artifacts:
          - name: in-artifact
            from: "{{steps.nested-wf.outputs.artifacts.nested-out-artifact}}"

  # container template which generates an output parameter and artifact
  - name: generate
    container:
      image: docker/whalesay:latest
      command: [sh, -c]
      args: ["
        cowsay hello world | tee /tmp/my-output-artifact.txt &&
        echo 'my-output-parameter' > /tmp/my-output-parameter.txt
      "]
    outputs:
      parameters:
      - name: out-parameter
        valueFrom:
          path: /tmp/my-output-parameter.txt
      artifacts:
      - name: out-artifact
        path: /tmp/my-output-artifact.txt

  # steps template which consumes an input artifact and also produces
  # its own output parameters and artifacts taken from one of its steps.
  - name: nested-wf
    inputs:
      parameters:
      - name: nested-in-parameter
      artifacts:
      - name: nested-in-artifact
    steps:
    - - name: consume
        template: consume
        arguments:
          parameters:
          - name: in-parameter
            value: "{{inputs.parameters.nested-in-parameter}}"
          artifacts:
          - name: in-artifact
            from: "{{inputs.artifacts.nested-in-artifact}}"
      - name: generate
        template: generate
    outputs:
      parameters:
      - name: nested-out-parameter
        valueFrom:
          parameter: "{{steps.generate.outputs.parameters.out-parameter}}"
      artifacts:
      - name: nested-out-artifact
        from: "{{steps.generate.outputs.artifacts.out-artifact}}"

  # container template which consumes an input parameter and artifact
  - name: consume
    inputs:
      parameters:
      - name: in-parameter
      artifacts:
      - name: in-artifact
        path: /tmp/art
    container:
      image: alpine:3.7
      command: [sh, -c]
      args: ["
        echo 'input parameter value: {{inputs.parameters.in-parameter}}' &&
        echo 'input artifact contents:' &&
        cat /tmp/art
      "]