Source code for tests.system.standard.example_external_task_parent_deferrable

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from __future__ import annotations

from airflow import DAG
from airflow.providers.standard.operators.empty import EmptyOperator
from airflow.providers.standard.operators.trigger_dagrun import TriggerDagRunOperator
from airflow.providers.standard.sensors.external_task import ExternalTaskSensor
from airflow.utils.timezone import datetime

with DAG(
    dag_id="example_external_task",
    start_date=datetime(2022, 1, 1),
    schedule="@once",
    catchup=False,
    tags=["example", "async", "core"],
) as dag:

[docs]
    start = EmptyOperator(task_id="start")


    # [START howto_external_task_async_sensor]
    external_task_sensor = ExternalTaskSensor(
        task_id="parent_task_sensor",
        external_task_id="child_task",
        external_dag_id="child_dag",
        deferrable=True,
    )
    # [END howto_external_task_async_sensor]

    trigger_child_task = TriggerDagRunOperator(
        task_id="trigger_child_task",
        trigger_dag_id="child_dag",
        allowed_states=[
            "success",
            "failed",
        ],
        logical_date="{{ logical_date }}",
        poke_interval=5,
        reset_dag_run=True,
        wait_for_completion=True,
    )

    end = EmptyOperator(task_id="end")

    start >> [trigger_child_task, external_task_sensor] >> end

    from tests_common.test_utils.watcher import watcher

    # This test needs watcher in order to properly mark success/failure
    # when "teardown" task with trigger rule is part of the DAG
    list(dag.tasks) >> watcher()


from tests_common.test_utils.system_tests import get_test_run

# Needed to run the example DAG with pytest (see: tests/system/README.md#run_via_pytest)

[docs]
test_run = get_test_run(dag)