Source code for airflow.example_dags.example_branch_labels

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"""
Example DAG demonstrating the usage of labels with different branches.
"""
from datetime import datetime

from airflow import DAG
from airflow.operators.dummy import DummyOperator
from airflow.utils.edgemodifier import Label

with DAG(
    "example_branch_labels", schedule_interval="@daily", start_date=datetime(2021, 1, 1), catchup=False
) as dag:
    ingest = DummyOperator(task_id="ingest")
    analyse = DummyOperator(task_id="analyze")
    check = DummyOperator(task_id="check_integrity")
    describe = DummyOperator(task_id="describe_integrity")
    error = DummyOperator(task_id="email_error")
    save = DummyOperator(task_id="save")
    report = DummyOperator(task_id="report")

    ingest >> analyse >> check
    check >> Label("No errors") >> save >> report
    check >> Label("Errors found") >> describe >> error >> report