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Dag Diamond With Script

This is the canonical “diamond” example shown in the README.

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from hera.workflows import DAG, Workflow, script


@script(image="python:3.12")
def echo(message):
    print(message)


with Workflow(generate_name="dag-diamond-", entrypoint="diamond") as w:
    with DAG(name="diamond"):
        A = echo(name="A", arguments={"message": "A"})
        B = echo(name="B", arguments={"message": "B"})
        C = echo(name="C", arguments={"message": "C"})
        D = echo(name="D", arguments={"message": "D"})
        A >> [B, C] >> D

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apiVersion: argoproj.io/v1alpha1
kind: Workflow
metadata:
  generateName: dag-diamond-
spec:
  entrypoint: diamond
  templates:
  - name: diamond
    dag:
      tasks:
      - name: A
        template: echo
        arguments:
          parameters:
          - name: message
            value: A
      - name: B
        depends: A
        template: echo
        arguments:
          parameters:
          - name: message
            value: B
      - name: C
        depends: A
        template: echo
        arguments:
          parameters:
          - name: message
            value: C
      - name: D
        depends: B && C
        template: echo
        arguments:
          parameters:
          - name: message
            value: D
  - name: echo
    inputs:
      parameters:
      - name: message
    script:
      image: python:3.12
      source: |-
        import os
        import sys
        sys.path.append(os.getcwd())
        import json
        try: message = json.loads(r'''{{inputs.parameters.message}}''')
        except: message = r'''{{inputs.parameters.message}}'''

        print(message)
      command:
      - python

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