Source code for airflow.example_dags.example_short_circuit_decorator

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"""Example DAG demonstrating the usage of the `@task.short_circuit()` TaskFlow decorator."""
from __future__ import annotations

import pendulum

from airflow.decorators import dag, task
from airflow.models.baseoperator import chain
from airflow.operators.empty import EmptyOperator
from airflow.utils.trigger_rule import TriggerRule

@dag(start_date=pendulum.datetime(2021, 1, 1, tz="UTC"), catchup=False, tags=["example"])
[docs]def example_short_circuit_decorator(): # [START howto_operator_short_circuit] @task.short_circuit() def check_condition(condition): return condition ds_true = [EmptyOperator(task_id="true_" + str(i)) for i in [1, 2]] ds_false = [EmptyOperator(task_id="false_" + str(i)) for i in [1, 2]] condition_is_true = check_condition.override(task_id="condition_is_true")(condition=True) condition_is_false = check_condition.override(task_id="condition_is_false")(condition=False) chain(condition_is_true, *ds_true) chain(condition_is_false, *ds_false) # [END howto_operator_short_circuit] # [START howto_operator_short_circuit_trigger_rules] [task_1, task_2, task_3, task_4, task_5, task_6] = [ EmptyOperator(task_id=f"task_{i}") for i in range(1, 7) ] task_7 = EmptyOperator(task_id="task_7", trigger_rule=TriggerRule.ALL_DONE) short_circuit = check_condition.override(task_id="short_circuit", ignore_downstream_trigger_rules=False)( condition=False ) chain(task_1, [task_2, short_circuit], [task_3, task_4], [task_5, task_6], task_7)
# [END howto_operator_short_circuit_trigger_rules]
[docs]example_dag = example_short_circuit_decorator()

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