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Template Level Volume

This is an upstream example that only appears in the docs.

See https://argo-workflows.readthedocs.io/en/latest/walk-through/volumes/

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from hera.workflows import (
    Container,
    ExistingVolume,
    Parameter,
    Resource,
    Step,
    Steps,
    Workflow,
)

with Workflow(
    generate_name="template-level-volume-",
    entrypoint="generate-and-use-volume",
) as w:
    generate_volume = Resource(
        name="generate-volume",
        inputs=[Parameter(name="pvc-size")],
        outputs=[Parameter(name="pvc-name", value_from={"jsonPath": "{.metadata.name}"})],
        action="create",
        set_owner_reference=True,
        manifest="""apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  generateName: pvc-example-
spec:
  accessModes: ['ReadWriteOnce', 'ReadOnlyMany']
  resources:
    requests:
      storage: '{{inputs.parameters.pvc-size}}'
""",
    )
    whalesay = Container(
        name="whalesay",
        inputs=[Parameter(name="pvc-name")],
        volumes=[ExistingVolume(name="workdir", claim_name="{{inputs.parameters.pvc-name}}", mount_path="/mnt/vol")],
        image="docker/whalesay:latest",
        command=["sh", "-c"],
        args=["echo generating message in volume; cowsay hello world | tee /mnt/vol/hello_world.txt"],
    )
    print_message = Container(
        name="print-message",
        inputs=[Parameter(name="pvc-name")],
        volumes=[ExistingVolume(name="workdir", claim_name="{{inputs.parameters.pvc-name}}", mount_path="/mnt/vol")],
        image="alpine:latest",
        command=["sh", "-c"],
        args=["echo getting message from volume; find /mnt/vol; cat /mnt/vol/hello_world.txt"],
    )
    with Steps(name="generate-and-use-volume") as s:
        generate_vol_step: Step = generate_volume(name="generate-volume", arguments={"pvc-size": "1Gi"})
        whalesay(name="generate", arguments=generate_vol_step.get_parameter("pvc-name"))
        print_message(name="print", arguments=generate_vol_step.get_parameter("pvc-name"))

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apiVersion: argoproj.io/v1alpha1
kind: Workflow
metadata:
  generateName: template-level-volume-
spec:
  entrypoint: generate-and-use-volume
  templates:
  - name: generate-and-use-volume
    steps:
    - - name: generate-volume
        template: generate-volume
        arguments:
          parameters:
            - name: pvc-size
              # In a real-world example, this could be generated by a previous workflow step.
              value: '1Gi'
    - - name: generate
        template: whalesay
        arguments:
          parameters:
            - name: pvc-name
              value: '{{steps.generate-volume.outputs.parameters.pvc-name}}'
    - - name: print
        template: print-message
        arguments:
          parameters:
            - name: pvc-name
              value: '{{steps.generate-volume.outputs.parameters.pvc-name}}'

  - name: generate-volume
    inputs:
      parameters:
        - name: pvc-size
    resource:
      action: create
      setOwnerReference: true
      manifest: |
        apiVersion: v1
        kind: PersistentVolumeClaim
        metadata:
          generateName: pvc-example-
        spec:
          accessModes: ['ReadWriteOnce', 'ReadOnlyMany']
          resources:
            requests:
              storage: '{{inputs.parameters.pvc-size}}'
    outputs:
      parameters:
        - name: pvc-name
          valueFrom:
            jsonPath: '{.metadata.name}'

  - name: whalesay
    inputs:
      parameters:
        - name: pvc-name
    volumes:
      - name: workdir
        persistentVolumeClaim:
          claimName: '{{inputs.parameters.pvc-name}}'
    container:
      image: docker/whalesay:latest
      command: [sh, -c]
      args: ["echo generating message in volume; cowsay hello world | tee /mnt/vol/hello_world.txt"]
      volumeMounts:
      - name: workdir
        mountPath: /mnt/vol

  - name: print-message
    inputs:
        parameters:
          - name: pvc-name
    volumes:
      - name: workdir
        persistentVolumeClaim:
          claimName: '{{inputs.parameters.pvc-name}}'
    container:
      image: alpine:latest
      command: [sh, -c]
      args: ["echo getting message from volume; find /mnt/vol; cat /mnt/vol/hello_world.txt"]
      volumeMounts:
      - name: workdir
        mountPath: /mnt/vol

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