Source code for airflow.models.skipmixin

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from airflow.models.taskinstance import TaskInstance
from airflow.utils import timezone
from airflow.utils.db import provide_session
from airflow.utils.log.logging_mixin import LoggingMixin
from airflow.utils.state import State

import six
from typing import Union, Iterable, Set


[docs]class SkipMixin(LoggingMixin): @provide_session
[docs] def skip(self, dag_run, execution_date, tasks, session=None): """ Sets tasks instances to skipped from the same dag run. :param dag_run: the DagRun for which to set the tasks to skipped :param execution_date: execution_date :param tasks: tasks to skip (not task_ids) :param session: db session to use """ if not tasks: return task_ids = [d.task_id for d in tasks] now = timezone.utcnow() if dag_run: session.query(TaskInstance).filter( TaskInstance.dag_id == dag_run.dag_id, TaskInstance.execution_date == dag_run.execution_date, TaskInstance.task_id.in_(task_ids) ).update({TaskInstance.state: State.SKIPPED, TaskInstance.start_date: now, TaskInstance.end_date: now}, synchronize_session=False) session.commit() else: assert execution_date is not None, "Execution date is None and no dag run" self.log.warning("No DAG RUN present this should not happen") # this is defensive against dag runs that are not complete for task in tasks: ti = TaskInstance(task, execution_date=execution_date) ti.state = State.SKIPPED ti.start_date = now ti.end_date = now session.merge(ti) session.commit()
[docs] def skip_all_except(self, ti, branch_task_ids): # type: (TaskInstance, Union[str, Iterable[str]]) -> None """ This method implements the logic for a branching operator; given a single task ID or list of task IDs to follow, this skips all other tasks immediately downstream of this operator. """ self.log.info("Following branch %s", branch_task_ids) if isinstance(branch_task_ids, six.string_types): branch_task_ids = [branch_task_ids] dag_run = ti.get_dagrun() task = ti.task dag = task.dag downstream_tasks = task.downstream_list if downstream_tasks: # Also check downstream tasks of the branch task. In case the task to skip # is also a downstream task of the branch task, we exclude it from skipping. branch_downstream_task_ids = set() # type: Set[str] for b in branch_task_ids: branch_downstream_task_ids.update(dag. get_task(b). get_flat_relative_ids(upstream=False)) skip_tasks = [t for t in downstream_tasks if t.task_id not in branch_task_ids and t.task_id not in branch_downstream_task_ids] self.log.info("Skipping tasks %s", [t.task_id for t in skip_tasks]) self.skip(dag_run, ti.execution_date, skip_tasks)