Source code for airflow.providers.standard.example_dags.example_latest_only

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"""### LatestOnlyOperator

Example DAG demonstrating the LatestOnlyOperator.

The LatestOnlyOperator skips downstream tasks for all DAG runs except the
most recent scheduled run. This is useful when downstream work should only run
for the latest interval, such as refreshing a dashboard or publishing a current
snapshot.

See also:
https://airflow.apache.org/docs/apache-airflow-providers-standard/stable/operators/latest_only.html
"""

from __future__ import annotations

import datetime

from airflow.providers.standard.operators.empty import EmptyOperator
from airflow.providers.standard.operators.latest_only import LatestOnlyOperator
from airflow.sdk import DAG

with DAG(
    dag_id="latest_only",
    schedule=datetime.timedelta(hours=4),
    start_date=datetime.datetime(2021, 1, 1),
    catchup=False,
    tags=["example2", "example3"],
    doc_md=__doc__,
) as dag:
    # [START howto_operator_latest_only]

[docs]
    latest_only = LatestOnlyOperator(task_id="latest_only")

    # [END howto_operator_latest_only]
    task1 = EmptyOperator(task_id="task1")

    latest_only >> task1