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from airflow.operators import BranchPythonOperator, DummyOperator
from airflow.models import DAG
from datetime import datetime, timedelta
import random
seven_days_ago = datetime.combine(datetime.today() - timedelta(7),
datetime.min.time())
args = {
'owner': 'airflow',
'start_date': seven_days_ago,
}
dag = DAG(dag_id='example_branch_operator', default_args=args)
cmd = 'ls -l'
run_this_first = DummyOperator(task_id='run_this_first', dag=dag)
options = ['branch_a', 'branch_b', 'branch_c', 'branch_d']
branching = BranchPythonOperator(
task_id='branching',
python_callable=lambda: random.choice(options),
dag=dag)
branching.set_upstream(run_this_first)
join = DummyOperator(
task_id='join',
trigger_rule='one_success',
dag=dag
)
for option in options:
t = DummyOperator(task_id=option, dag=dag)
t.set_upstream(branching)
dummy_follow = DummyOperator(task_id='follow_' + option, dag=dag)
t.set_downstream(dummy_follow)
dummy_follow.set_downstream(join)
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