airflow/jobs.py
def _change_state_for_executable_task_instances(self, task_instances,
                                                    acceptable_states, session=None):
        """
        Changes the state of task instances in the list with one of the given states
        to QUEUED atomically, and returns the TIs changed in SimpleTaskInstance format.

        :param task_instances: TaskInstances to change the state of
        :type task_instances: list[airflow.models.TaskInstance]
        :param acceptable_states: Filters the TaskInstances updated to be in these states
        :type acceptable_states: Iterable[State]
        :rtype: list[airflow.utils.dag_processing.SimpleTaskInstance]
        """
        if len(task_instances) == 0:
            session.commit()
            return []

        TI = models.TaskInstance
        filter_for_ti_state_change = (
            [and_(
                TI.dag_id == ti.dag_id,
                TI.task_id == ti.task_id,
                TI.execution_date == ti.execution_date)
                for ti in task_instances])
        ti_query = (
            session
            .query(TI)
            .filter(or_(*filter_for_ti_state_change)))

        if None in acceptable_states:
            ti_query = ti_query.filter(
                or_(TI.state == None, TI.state.in_(acceptable_states))  # noqa: E711
            )
        else:
            ti_query = ti_query.filter(TI.state.in_(acceptable_states))

        tis_to_set_to_queued = (
            ti_query
            .with_for_update()
            .all())
        if len(tis_to_set_to_queued) == 0:
            self.log.info("No tasks were able to have their state changed to queued.")
            session.commit()
            return []

        # set TIs to queued state
        for task_instance in tis_to_set_to_queued:
            task_instance.state = State.QUEUED
            task_instance.queued_dttm = (timezone.utcnow()
                                         if not task_instance.queued_dttm
                                         else task_instance.queued_dttm)
            session.merge(task_instance)

        # Generate a list of SimpleTaskInstance for the use of queuing
        # them in the executor.
        simple_task_instances = [SimpleTaskInstance(ti) for ti in
                                 tis_to_set_to_queued]

        task_instance_str = "\n\t".join(
            [repr(x) for x in tis_to_set_to_queued])

        session.commit()
        self.log.info("Setting the following %s tasks to queued state:\n\t%s",
                      len(tis_to_set_to_queued), task_instance_str)
        return simple_task_instances
def _change_state_for_executable_task_instances(self, task_instances,
                                                    acceptable_states, session=None):
        """
        Changes the state of task instances in the list with one of the given states
        to QUEUED atomically, and returns the TIs changed in SimpleTaskInstance format.

        :param task_instances: TaskInstances to change the state of
        :type task_instances: list[airflow.models.TaskInstance]
        :param acceptable_states: Filters the TaskInstances updated to be in these states
        :type acceptable_states: Iterable[State]
        :rtype: list[airflow.utils.dag_processing.SimpleTaskInstance]
        """
        if len(task_instances) == 0:
            session.commit()
            return []

        TI = models.TaskInstance
        filter_for_ti_state_change = (
            [and_(
                TI.dag_id == ti.dag_id,
                TI.task_id == ti.task_id,
                TI.execution_date == ti.execution_date)
                for ti in task_instances])
        ti_query = (
            session
            .query(TI)
            .filter(or_(*filter_for_ti_state_change)))

        if None in acceptable_states:
            ti_query = ti_query.filter(
                or_(TI.state == None, TI.state.in_(acceptable_states))  # noqa: E711
            )
        else:
            ti_query = ti_query.filter(TI.state.in_(acceptable_states))

        tis_to_set_to_queued = (
            ti_query
            .with_for_update()
            .all())
        if len(tis_to_set_to_queued) == 0:
            self.log.info("No tasks were able to have their state changed to queued.")
            session.commit()
            return []

        # set TIs to queued state
        for task_instance in tis_to_set_to_queued:
            task_instance.state = State.QUEUED
            task_instance.queued_dttm = (timezone.utcnow()
                                         if not task_instance.queued_dttm
                                         else task_instance.queued_dttm)
            session.merge(task_instance)

        # Generate a list of SimpleTaskInstance for the use of queuing
        # them in the executor.
        simple_task_instances = [SimpleTaskInstance(ti) for ti in
                                 tis_to_set_to_queued]

        task_instance_str = "\n\t".join(
            [repr(x) for x in tis_to_set_to_queued])

        session.commit()
        self.log.info("Setting the following %s tasks to queued state:\n\t%s",
                      len(tis_to_set_to_queued), task_instance_str)
        return simple_task_instances
Changes the state of task instances in the list with one of the given states
        to QUEUED atomically, and returns the TIs changed in SimpleTaskInstance format.

        :param task_instances: TaskInstances to change the state of
        :type task_instances: list[airflow.models.TaskInstance]
        :param acceptable_states: Filters the TaskInstances updated to be in these states
        :type acceptable_states: Iterable[State]
        :rtype: list[airflow.utils.dag_processing.SimpleTaskInstance]