Source code for airflow.decorators.setup_teardown

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from __future__ import annotations

import types
from typing import Callable

from airflow import AirflowException, XComArg
from airflow.decorators import python_task
from airflow.decorators.task_group import _TaskGroupFactory
from airflow.models import BaseOperator
from airflow.utils.setup_teardown import SetupTeardownContext


[docs]def setup_task(func: Callable) -> Callable:
    # Using FunctionType here since _TaskDecorator is also a callable
    if isinstance(func, types.FunctionType):
        func = python_task(func)
    if isinstance(func, _TaskGroupFactory):
        raise AirflowException("Task groups cannot be marked as setup or teardown.")
    func.is_setup = True  # type: ignore[attr-defined]
    return func


[docs]def teardown_task(_func=None, *, on_failure_fail_dagrun: bool = False) -> Callable:
    def teardown(func: Callable) -> Callable:
        # Using FunctionType here since _TaskDecorator is also a callable
        if isinstance(func, types.FunctionType):
            func = python_task(func)
        if isinstance(func, _TaskGroupFactory):
            raise AirflowException("Task groups cannot be marked as setup or teardown.")
        func.is_teardown = True  # type: ignore[attr-defined]
        func.on_failure_fail_dagrun = on_failure_fail_dagrun  # type: ignore[attr-defined]
        return func

    if _func is None:
        return teardown
    return teardown(_func)


[docs]class ContextWrapper(list):
    """A list subclass that has a context manager that pushes setup/teardown tasks to the context."""

    def __init__(self, tasks: list[BaseOperator | XComArg]):
        self.tasks = tasks
        super().__init__(tasks)

[docs]    def __enter__(self):
        operators = []
        for task in self.tasks:
            if isinstance(task, BaseOperator):
                operators.append(task)
                if not task.is_setup and not task.is_teardown:
                    raise AirflowException("Only setup/teardown tasks can be used as context managers.")
            elif not task.operator.is_setup and not task.operator.is_teardown:
                raise AirflowException("Only setup/teardown tasks can be used as context managers.")
        if not operators:
            # means we have XComArgs
            operators = [task.operator for task in self.tasks]
        SetupTeardownContext.push_setup_teardown_task(operators)
        return SetupTeardownContext

[docs]    def __exit__(self, exc_type, exc_val, exc_tb):
        SetupTeardownContext.set_work_task_roots_and_leaves()


[docs]context_wrapper = ContextWrapper