Example:
with DAG( "fraud_detection", xcom_exclusive_keys= "fetch_transactions": ["raw_txns"], "validate": ["valid_txns", "error_count"], "feature_engineering": ["features"], "fraud_model": ["score"], , xcom_backend="myapp.xcom.S3ExclusiveXCom", ) as dag: airflow xcom exclusive
@classmethod def get_value(cls, key, dag_id, task_id, run_id, map_index): # Enforce exclusive pull: only if (dag_id, calling_task, target_task) is allowed calling_task = task_id # Note: in real implementation, you'd need to resolve caller allowed_keys = cls.ALLOWED_PULLS.get((dag_id, calling_task), []) if key not in allowed_keys: raise AirflowException( f"XCom exclusive violation: Task calling_task not allowed to pull key 'key'" ) return super().get_value(key, dag_id, task_id, run_id, map_index) Inside your DAG, push with a unique key per execution date: Example: with DAG( "fraud_detection"