test_subdag.py

#
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.
"""
A DAG with subdag for testing purpose.
"""
from __future__ import annotations

import warnings
from datetime import datetime, timedelta

from airflow.models.dag import DAG
from airflow.operators.empty import EmptyOperator
from airflow.operators.subdag import SubDagOperator

DAG_NAME = "test_subdag_operator"

DEFAULT_TASK_ARGS = {
    "owner": "airflow",
    "start_date": datetime(2019, 1, 1),
    "max_active_runs": 1,
}


def subdag(parent_dag_name, child_dag_name, args):
    """
    Create a subdag.
    """
    dag_subdag = DAG(
        dag_id=f"{parent_dag_name}.{child_dag_name}",
        default_args=args,
        schedule="@daily",
    )

    for i in range(2):
        EmptyOperator(
            task_id=f"{child_dag_name}-task-{i + 1}",
            default_args=args,
            dag=dag_subdag,
        )

    return dag_subdag


with DAG(
    dag_id=DAG_NAME,
    start_date=datetime(2019, 1, 1),
    max_active_runs=1,
    default_args=DEFAULT_TASK_ARGS,
    schedule=timedelta(minutes=1),
):

    start = EmptyOperator(
        task_id="start",
    )

    with warnings.catch_warnings(record=True):
        section_1 = SubDagOperator(
            task_id="section-1",
            subdag=subdag(DAG_NAME, "section-1", DEFAULT_TASK_ARGS),
            default_args=DEFAULT_TASK_ARGS,
        )

    some_other_task = EmptyOperator(
        task_id="some-other-task",
    )

    start >> section_1 >> some_other_task