#
# 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.

from datetime import datetime, timedelta

from airflow import DAG
from airflow.operators.bash_operator import BashOperator
from airflow.providers.singularity.operators.singularity import SingularityOperator

default_args = {
    'owner': 'airflow',
    'depends_on_past': False,
    'start_date': datetime.utcnow(),
    'email': ['airflow@example.com'],
    'email_on_failure': False,
    'email_on_retry': False,
    'retries': 1,
    'retry_delay': timedelta(minutes=5)
}

dag = DAG(
    'singularity_sample', default_args=default_args, schedule_interval=timedelta(minutes=10))

t1 = BashOperator(
    task_id='print_date',
    bash_command='date',
    dag=dag)

t2 = BashOperator(
    task_id='sleep',
    bash_command='sleep 5',
    retries=3,
    dag=dag)

t3 = SingularityOperator(command='/bin/sleep 30',
                         image='docker://busybox:1.30.1',
                         task_id='singularity_op_tester',
                         dag=dag)

t4 = BashOperator(
    task_id='print_hello',
    bash_command='echo "hello world!!!"',
    dag=dag)

t1.set_downstream(t2)
t1.set_downstream(t3)
t3.set_downstream(t4)

#
# 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.

from datetime import timedelta

from airflow import DAG
from airflow.operators.bash_operator import BashOperator
from airflow.providers.singularity.operators.singularity import SingularityOperator
from airflow.utils.dates import days_ago

default_args = {
    'owner': 'airflow',
    'depends_on_past': False,
    'email': ['airflow@example.com'],
    'email_on_failure': False,
    'email_on_retry': False,
    'retries': 1,
    'retry_delay': timedelta(minutes=5)
}

with DAG('singularity_sample',
         default_args=default_args,
         schedule_interval=timedelta(minutes=10),
         start_date=days_ago(0)) as dag:

    t1 = BashOperator(
        task_id='print_date',
        bash_command='date',
        dag=dag)

    t2 = BashOperator(
        task_id='sleep',
        bash_command='sleep 5',
        retries=3,
        dag=dag)

    t3 = SingularityOperator(command='/bin/sleep 30',
                             image='docker://busybox:1.30.1',
                             task_id='singularity_op_tester',
                             dag=dag)

    t4 = BashOperator(
        task_id='print_hello',
        bash_command='echo "hello world!!!"',
        dag=dag)

    t1 >> [t2, t3]
    t3 >> t4

Update example SingularityOperator DAG (#8790)