trigger_target_dag

Example usage of the TriggerDagRunOperator. This example holds 2 DAGs: 1. 1st DAG (example_trigger_controller_dag) holds a TriggerDagRunOperator, which will trigger the 2nd DAG 2. 2nd DAG (example_trigger_target_dag) which will be triggered by the TriggerDagRunOperator in the 1st DAG

Airflow Fundamentals


Providers:

Run this DAG

1. Install Astronomer CLISkip if you already have the CLI

2. Initate the project:

3. Copy and paste the code below into a file in the

dags
directory.

4. Add the following to your requirements.txt file:

5. Run the DAG:

#
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# to you under the Apache License, Version 2.0 (the
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"""
Example usage of the TriggerDagRunOperator. This example holds 2 DAGs:
1. 1st DAG (example_trigger_controller_dag) holds a TriggerDagRunOperator, which will trigger the 2nd DAG
2. 2nd DAG (example_trigger_target_dag) which will be triggered by the TriggerDagRunOperator in the 1st DAG
"""
from airflow import DAG
from airflow.operators.bash import BashOperator
from airflow.operators.python import PythonOperator
from airflow.utils.dates import days_ago
def run_this_func(**context):
"""
Print the payload "message" passed to the DagRun conf attribute.
:param context: The execution context
:type context: dict
"""
print(f"Remotely received value of {context['dag_run'].conf['message']} for key=message")
with DAG(
dag_id="example_trigger_target_dag",
default_args={"owner": "airflow"},
start_date=days_ago(2),
schedule_interval=None,
tags=['example'],
) as dag:
run_this = PythonOperator(task_id="run_this", python_callable=run_this_func)
bash_task = BashOperator(
task_id="bash_task",
bash_command='echo "Here is the message: $message"',
env={'message': '{{ dag_run.conf["message"] if dag_run else "" }}'},
)