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:mod:`airflow.models.dagrun`
============================
.. py:module:: airflow.models.dagrun
Module Contents
---------------
.. py:class:: DagRun
Bases: :class:`airflow.models.base.Base`, :class:`airflow.utils.log.logging_mixin.LoggingMixin`
DagRun describes an instance of a Dag. It can be created
by the scheduler (for regular runs) or by an external trigger
.. attribute:: __tablename__
:annotation: = dag_run
.. attribute:: ID_PREFIX
:annotation: = scheduled__
.. attribute:: ID_FORMAT_PREFIX
.. attribute:: id
.. attribute:: dag_id
.. attribute:: execution_date
.. attribute:: start_date
.. attribute:: end_date
.. attribute:: _state
.. attribute:: run_id
.. attribute:: external_trigger
.. attribute:: conf
.. attribute:: dag
.. attribute:: __table_args__
.. attribute:: state
.. attribute:: is_backfill
.. method:: __repr__(self)
.. method:: get_state(self)
.. method:: set_state(self, state)
.. classmethod:: id_for_date(cls, date, prefix=ID_FORMAT_PREFIX)
.. method:: refresh_from_db(self, session=None)
Reloads the current dagrun from the database
:param session: database session
.. staticmethod:: find(dag_id=None, run_id=None, execution_date=None, state=None, external_trigger=None, no_backfills=False, session=None)
Returns a set of dag runs for the given search criteria.
:param dag_id: the dag_id to find dag runs for
:type dag_id: int, list
:param run_id: defines the the run id for this dag run
:type run_id: str
:param execution_date: the execution date
:type execution_date: datetime.datetime
:param state: the state of the dag run
:type state: str
:param external_trigger: whether this dag run is externally triggered
:type external_trigger: bool
:param no_backfills: return no backfills (True), return all (False).
Defaults to False
:type no_backfills: bool
:param session: database session
:type session: sqlalchemy.orm.session.Session
.. method:: get_task_instances(self, state=None, session=None)
Returns the task instances for this dag run
.. method:: get_task_instance(self, task_id, session=None)
Returns the task instance specified by task_id for this dag run
:param task_id: the task id
.. method:: get_dag(self)
Returns the Dag associated with this DagRun.
:return: DAG
.. method:: get_previous_dagrun(self, state=None, session=None)
The previous DagRun, if there is one
.. method:: get_previous_scheduled_dagrun(self, session=None)
The previous, SCHEDULED DagRun, if there is one
.. method:: update_state(self, session=None)
Determines the overall state of the DagRun based on the state
of its TaskInstances.
:return: ready_tis: the tis that can be scheduled in the current loop
:rtype ready_tis: list[airflow.models.TaskInstance]
.. method:: _get_ready_tis(self, scheduleable_tasks, finished_tasks, session)
.. method:: _are_premature_tis(self, unfinished_tasks, finished_tasks, session)
.. method:: _emit_true_scheduling_delay_stats_for_finished_state(self, finished_tis)
This is a helper method to emit the true scheduling delay stats, which is defined as
the time when the first task in DAG starts minus the expected DAG run datetime.
This method will be used in the update_state method when the state of the DagRun
is updated to a completed status (either success or failure). The method will find the first
started task within the DAG and calculate the expected DagRun start time (based on
dag.execution_date & dag.schedule_interval), and minus these two values to get the delay.
The emitted data may contains outlier (e.g. when the first task was cleared, so
the second task's start_date will be used), but we can get rid of the the outliers
on the stats side through the dashboards tooling built.
Note, the stat will only be emitted if the DagRun is a scheduler triggered one
(i.e. external_trigger is False).
.. method:: _emit_duration_stats_for_finished_state(self)
.. method:: verify_integrity(self, session=None)
Verifies the DagRun by checking for removed tasks or tasks that are not in the
database yet. It will set state to removed or add the task if required.
.. staticmethod:: get_run(session, dag_id, execution_date)
:param dag_id: DAG ID
:type dag_id: unicode
:param execution_date: execution date
:type execution_date: datetime
:return: DagRun corresponding to the given dag_id and execution date
if one exists. None otherwise.
:rtype: airflow.models.DagRun
.. classmethod:: get_latest_runs(cls, session)
Returns the latest DagRun for each DAG.