Source code for airflow.example_dags.example_task_group_decorator
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"""Example DAG demonstrating the usage of the @taskgroup decorator."""
from __future__ import annotations
import pendulum
from airflow.decorators import task, task_group
from airflow.models.dag import DAG
# [START howto_task_group_decorator]
# Creating Tasks
@task
[docs]def task_start():
"""Empty Task which is First Task of Dag"""
return "[Task_start]"
@task
[docs]def task_1(value: int) -> str:
"""Empty Task1"""
return f"[ Task1 {value} ]"
@task
[docs]def task_2(value: str) -> str:
"""Empty Task2"""
return f"[ Task2 {value} ]"
@task
[docs]def task_3(value: str) -> None:
"""Empty Task3"""
print(f"[ Task3 {value} ]")
@task
[docs]def task_end() -> None:
"""Empty Task which is Last Task of Dag"""
print("[ Task_End ]")
# Creating TaskGroups
@task_group
[docs]def task_group_function(value: int) -> None:
"""TaskGroup for grouping related Tasks"""
task_3(task_2(task_1(value)))
# Executing Tasks and TaskGroups
with DAG(
dag_id="example_task_group_decorator",
start_date=pendulum.datetime(2021, 1, 1, tz="UTC"),
catchup=False,
tags=["example"],
) as dag:
[docs] start_task = task_start()
end_task = task_end()
for i in range(5):
current_task_group = task_group_function(i)
start_task >> current_task_group >> end_task
# [END howto_task_group_decorator]