src/pydolphinscheduler/examples/task_switch_example.py

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# [start workflow_declare]
r"""
A example workflow for task switch.

This example will create four task in single workflow, with three shell task and one switch task. Task switch
have one upstream which we declare explicit with syntax `parent >> switch`, and two downstream automatically
set dependence by switch task by passing parameter `condition`. The graph of this workflow like:
                      --> switch_child_1
                    /
parent -> switch ->
                    \
                      --> switch_child_2
.
"""

from pydolphinscheduler.core.workflow import Workflow
from pydolphinscheduler.tasks.shell import Shell
from pydolphinscheduler.tasks.switch import Branch, Default, Switch, SwitchCondition

with Workflow(name="task_switch_example", param={"var": "1"}) as workflow:
    parent = Shell(name="parent", command="echo parent")
    switch_child_1 = Shell(name="switch_child_1", command="echo switch_child_1")
    switch_child_2 = Shell(name="switch_child_2", command="echo switch_child_2")
    switch_condition = SwitchCondition(
        Branch(condition="${var} > 1", task=switch_child_1),
        Default(task=switch_child_2),
    )

    switch = Switch(name="switch", condition=switch_condition)
    parent >> switch
    workflow.submit()
# [end workflow_declare]