branch_external_python.py

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from __future__ import annotations

from typing import TYPE_CHECKING, Callable

from airflow.decorators.base import task_decorator_factory
from airflow.decorators.python import _PythonDecoratedOperator
from airflow.operators.python import BranchExternalPythonOperator

if TYPE_CHECKING:
    from airflow.decorators.base import TaskDecorator


class _BranchExternalPythonDecoratedOperator(_PythonDecoratedOperator, BranchExternalPythonOperator):
    """Wraps a Python callable and captures args/kwargs when called for execution."""

    custom_operator_name: str = "@task.branch_external_python"


def branch_external_python_task(
    python_callable: Callable | None = None, multiple_outputs: bool | None = None, **kwargs
) -> TaskDecorator:
    """
    Wrap a python function into a BranchExternalPythonOperator.

    For more information on how to use this operator, take a look at the guide:
    :ref:`concepts:branching`

    Accepts kwargs for operator kwarg. Can be reused in a single DAG.

    :param python_callable: Function to decorate
    :param multiple_outputs: if set, function return value will be
        unrolled to multiple XCom values. Dict will unroll to xcom values with keys as XCom keys.
        Defaults to False.
    """
    return task_decorator_factory(
        python_callable=python_callable,
        multiple_outputs=multiple_outputs,
        decorated_operator_class=_BranchExternalPythonDecoratedOperator,
        **kwargs,
    )