xcomargs

Example DAG demonstrating the usage of the XComArgs.

Airflow Fundamentals


Providers:

Modules:

Last Updated: Apr. 13, 2022

Run this DAG

1. Install the Astronomer CLI:Skip if you already have the CLI

2. Initate the project in a local directory:

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

dags
directory.

4. Run the DAG from the local directory where the project was initiated:

#
# 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.
"""Example DAG demonstrating the usage of the XComArgs."""
from __future__ import annotations
import logging
import pendulum
from airflow import DAG
from airflow.decorators import task
from airflow.operators.bash import BashOperator
log = logging.getLogger(__name__)
@task
def generate_value():
"""Empty function"""
return "Bring me a shrubbery!"
@task
def print_value(value, ts=None):
"""Empty function"""
log.info("The knights of Ni say: %s (at %s)", value, ts)
with DAG(
dag_id='example_xcom_args',
start_date=pendulum.datetime(2021, 1, 1, tz="UTC"),
catchup=False,
schedule=None,
tags=['example'],
) as dag:
print_value(generate_value())
with DAG(
"example_xcom_args_with_operators",
start_date=pendulum.datetime(2021, 1, 1, tz="UTC"),
catchup=False,
schedule=None,
tags=['example'],
) as dag2:
bash_op1 = BashOperator(task_id="c", bash_command="echo c")
bash_op2 = BashOperator(task_id="d", bash_command="echo c")
xcom_args_a = print_value("first!")
xcom_args_b = print_value("second!")
bash_op1 >> xcom_args_a >> xcom_args_b >> bash_op2