No xcom_push or xcom_pull needed – the TaskFlow wiring handles it. With traditional operators, you must push/pull manually.
from airflow.operators.python import PythonOperator def push_function(**context): context['ti'].xcom_push(key='user_id', value=123)
XComs are not designed for large data. Default size limit is 1 MB (configurable, but don’t). Use them for IDs, file paths, dates, small JSON – not DataFrames or images. The Two Ways to Use XComs 1. Implicit XComs via return Any Python function decorated with @task (TaskFlow API) automatically pushes its return value as an XCom. xcom in airflow
push = PythonOperator(task_id='push_task', python_callable=push_function) pull = PythonOperator(task_id='pull_task', python_callable=pull_function)
XCom (short for cross‑communication ) is Airflow’s built‑in mechanism for exchanging small pieces of data between tasks. When used wisely, they unlock powerful patterns. When abused, they break your DAGs. Let’s see how to use them correctly. XComs are key‑value pairs stored in Airflow’s metadata database. A task can push an XCom (write a value under a key), and another task can pull that value (read it). No xcom_push or xcom_pull needed – the TaskFlow
aggregate(download.expand(url=fetch_urls()))
@task def process(user_data: dict) -> str: return f"Processed user user_data['name']" Default size limit is 1 MB (configurable, but don’t)
from airflow.decorators import dag, task from datetime import datetime @dag(start_date=datetime(2024,1,1), schedule=None, catchup=False) def xcom_demo():
