blob: 42845b34bdd0e06fd1b59626eeac0939992def70 [file] [log] [blame]
#
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements. See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership. The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
from __future__ import annotations
import itertools
import os
import warnings
from collections import defaultdict
from datetime import datetime
from typing import TYPE_CHECKING, Any, Callable, Iterable, Iterator, NamedTuple, Sequence, TypeVar, overload
from sqlalchemy import (
Boolean,
Column,
ForeignKey,
ForeignKeyConstraint,
Index,
Integer,
PickleType,
PrimaryKeyConstraint,
String,
Text,
UniqueConstraint,
and_,
func,
or_,
text,
)
from sqlalchemy.exc import IntegrityError
from sqlalchemy.ext.associationproxy import association_proxy
from sqlalchemy.orm import Query, Session, declared_attr, joinedload, relationship, synonym
from sqlalchemy.sql.expression import false, select, true
from airflow import settings
from airflow.callbacks.callback_requests import DagCallbackRequest
from airflow.configuration import conf as airflow_conf
from airflow.exceptions import AirflowException, RemovedInAirflow3Warning, TaskNotFound
from airflow.listeners.listener import get_listener_manager
from airflow.models.abstractoperator import NotMapped
from airflow.models.base import Base, StringID
from airflow.models.expandinput import NotFullyPopulated
from airflow.models.taskinstance import TaskInstance as TI
from airflow.models.tasklog import LogTemplate
from airflow.stats import Stats
from airflow.ti_deps.dep_context import DepContext
from airflow.ti_deps.dependencies_states import SCHEDULEABLE_STATES
from airflow.typing_compat import Literal
from airflow.utils import timezone
from airflow.utils.helpers import chunks, is_container, prune_dict
from airflow.utils.log.logging_mixin import LoggingMixin
from airflow.utils.session import NEW_SESSION, provide_session
from airflow.utils.sqlalchemy import UtcDateTime, nulls_first, skip_locked, tuple_in_condition, with_row_locks
from airflow.utils.state import DagRunState, State, TaskInstanceState
from airflow.utils.types import NOTSET, ArgNotSet, DagRunType
if TYPE_CHECKING:
from airflow.models.dag import DAG
from airflow.models.operator import Operator
CreatedTasks = TypeVar("CreatedTasks", Iterator["dict[str, Any]"], Iterator[TI])
TaskCreator = Callable[[Operator, Iterable[int]], CreatedTasks]
class TISchedulingDecision(NamedTuple):
"""Type of return for DagRun.task_instance_scheduling_decisions."""
tis: list[TI]
schedulable_tis: list[TI]
changed_tis: bool
unfinished_tis: list[TI]
finished_tis: list[TI]
def _creator_note(val):
"""Custom creator for the ``note`` association proxy."""
if isinstance(val, str):
return DagRunNote(content=val)
elif isinstance(val, dict):
return DagRunNote(**val)
else:
return DagRunNote(*val)
class DagRun(Base, LoggingMixin):
"""Invocation instance of a DAG.
A DAG run can be created by the scheduler (i.e. scheduled runs), or by an
external trigger (i.e. manual runs).
"""
__tablename__ = "dag_run"
id = Column(Integer, primary_key=True)
dag_id = Column(StringID(), nullable=False)
queued_at = Column(UtcDateTime)
execution_date = Column(UtcDateTime, default=timezone.utcnow, nullable=False)
start_date = Column(UtcDateTime)
end_date = Column(UtcDateTime)
_state = Column("state", String(50), default=State.QUEUED)
run_id = Column(StringID(), nullable=False)
creating_job_id = Column(Integer)
external_trigger = Column(Boolean, default=True)
run_type = Column(String(50), nullable=False)
conf = Column(PickleType)
# These two must be either both NULL or both datetime.
data_interval_start = Column(UtcDateTime)
data_interval_end = Column(UtcDateTime)
# When a scheduler last attempted to schedule TIs for this DagRun
last_scheduling_decision = Column(UtcDateTime)
dag_hash = Column(String(32))
# Foreign key to LogTemplate. DagRun rows created prior to this column's
# existence have this set to NULL. Later rows automatically populate this on
# insert to point to the latest LogTemplate entry.
log_template_id = Column(
Integer,
ForeignKey("log_template.id", name="task_instance_log_template_id_fkey", ondelete="NO ACTION"),
default=select(func.max(LogTemplate.__table__.c.id)),
)
updated_at = Column(UtcDateTime, default=timezone.utcnow, onupdate=timezone.utcnow)
# Remove this `if` after upgrading Sphinx-AutoAPI
if not TYPE_CHECKING and "BUILDING_AIRFLOW_DOCS" in os.environ:
dag: DAG | None
else:
dag: DAG | None = None
__table_args__ = (
Index("dag_id_state", dag_id, _state),
UniqueConstraint("dag_id", "execution_date", name="dag_run_dag_id_execution_date_key"),
UniqueConstraint("dag_id", "run_id", name="dag_run_dag_id_run_id_key"),
Index("idx_last_scheduling_decision", last_scheduling_decision),
Index("idx_dag_run_dag_id", dag_id),
Index(
"idx_dag_run_running_dags",
"state",
"dag_id",
postgresql_where=text("state='running'"),
mssql_where=text("state='running'"),
sqlite_where=text("state='running'"),
),
# since mysql lacks filtered/partial indices, this creates a
# duplicate index on mysql. Not the end of the world
Index(
"idx_dag_run_queued_dags",
"state",
"dag_id",
postgresql_where=text("state='queued'"),
mssql_where=text("state='queued'"),
sqlite_where=text("state='queued'"),
),
)
task_instances = relationship(
TI, back_populates="dag_run", cascade="save-update, merge, delete, delete-orphan"
)
dag_model = relationship(
"DagModel",
primaryjoin="foreign(DagRun.dag_id) == DagModel.dag_id",
uselist=False,
viewonly=True,
)
dag_run_note = relationship(
"DagRunNote",
back_populates="dag_run",
uselist=False,
cascade="all, delete, delete-orphan",
)
note = association_proxy("dag_run_note", "content", creator=_creator_note)
DEFAULT_DAGRUNS_TO_EXAMINE = airflow_conf.getint(
"scheduler",
"max_dagruns_per_loop_to_schedule",
fallback=20,
)
def __init__(
self,
dag_id: str | None = None,
run_id: str | None = None,
queued_at: datetime | None | ArgNotSet = NOTSET,
execution_date: datetime | None = None,
start_date: datetime | None = None,
external_trigger: bool | None = None,
conf: Any | None = None,
state: DagRunState | None = None,
run_type: str | None = None,
dag_hash: str | None = None,
creating_job_id: int | None = None,
data_interval: tuple[datetime, datetime] | None = None,
):
if data_interval is None:
# Legacy: Only happen for runs created prior to Airflow 2.2.
self.data_interval_start = self.data_interval_end = None
else:
self.data_interval_start, self.data_interval_end = data_interval
self.dag_id = dag_id
self.run_id = run_id
self.execution_date = execution_date
self.start_date = start_date
self.external_trigger = external_trigger
self.conf = conf or {}
if state is not None:
self.state = state
if queued_at is NOTSET:
self.queued_at = timezone.utcnow() if state == State.QUEUED else None
else:
self.queued_at = queued_at
self.run_type = run_type
self.dag_hash = dag_hash
self.creating_job_id = creating_job_id
super().__init__()
def __repr__(self):
return (
"<DagRun {dag_id} @ {execution_date}: {run_id}, state:{state}, "
"queued_at: {queued_at}. externally triggered: {external_trigger}>"
).format(
dag_id=self.dag_id,
execution_date=self.execution_date,
run_id=self.run_id,
state=self.state,
queued_at=self.queued_at,
external_trigger=self.external_trigger,
)
@property
def stats_tags(self) -> dict[str, str]:
return prune_dict({"dag_id": self.dag_id, "run_type": self.run_type})
@property
def logical_date(self) -> datetime:
return self.execution_date
def get_state(self):
return self._state
def set_state(self, state: DagRunState):
if state not in State.dag_states:
raise ValueError(f"invalid DagRun state: {state}")
if self._state != state:
self._state = state
self.end_date = timezone.utcnow() if self._state in State.finished else None
if state == State.QUEUED:
self.queued_at = timezone.utcnow()
@declared_attr
def state(self):
return synonym("_state", descriptor=property(self.get_state, self.set_state))
@provide_session
def refresh_from_db(self, session: Session = NEW_SESSION) -> None:
"""
Reloads the current dagrun from the database.
:param session: database session
"""
dr = session.query(DagRun).filter(DagRun.dag_id == self.dag_id, DagRun.run_id == self.run_id).one()
self.id = dr.id
self.state = dr.state
@classmethod
@provide_session
def active_runs_of_dags(
cls,
dag_ids: Iterable[str] | None = None,
only_running: bool = False,
session: Session = NEW_SESSION,
) -> dict[str, int]:
"""Get the number of active dag runs for each dag."""
query = session.query(cls.dag_id, func.count("*"))
if dag_ids is not None:
# 'set' called to avoid duplicate dag_ids, but converted back to 'list'
# because SQLAlchemy doesn't accept a set here.
query = query.filter(cls.dag_id.in_(set(dag_ids)))
if only_running:
query = query.filter(cls.state == State.RUNNING)
else:
query = query.filter(cls.state.in_([State.RUNNING, State.QUEUED]))
query = query.group_by(cls.dag_id)
return {dag_id: count for dag_id, count in query.all()}
@classmethod
def next_dagruns_to_examine(
cls,
state: DagRunState,
session: Session,
max_number: int | None = None,
) -> Query:
"""
Return the next DagRuns that the scheduler should attempt to schedule.
This will return zero or more DagRun rows that are row-level-locked with a "SELECT ... FOR UPDATE"
query, you should ensure that any scheduling decisions are made in a single transaction -- as soon as
the transaction is committed it will be unlocked.
"""
from airflow.models.dag import DagModel
if max_number is None:
max_number = cls.DEFAULT_DAGRUNS_TO_EXAMINE
# TODO: Bake this query, it is run _A lot_
query = (
session.query(cls)
.with_hint(cls, "USE INDEX (idx_dag_run_running_dags)", dialect_name="mysql")
.filter(cls.state == state, cls.run_type != DagRunType.BACKFILL_JOB)
.join(DagModel, DagModel.dag_id == cls.dag_id)
.filter(DagModel.is_paused == false(), DagModel.is_active == true())
)
if state == State.QUEUED:
# For dag runs in the queued state, we check if they have reached the max_active_runs limit
# and if so we drop them
running_drs = (
session.query(DagRun.dag_id, func.count(DagRun.state).label("num_running"))
.filter(DagRun.state == DagRunState.RUNNING)
.group_by(DagRun.dag_id)
.subquery()
)
query = query.outerjoin(running_drs, running_drs.c.dag_id == DagRun.dag_id).filter(
func.coalesce(running_drs.c.num_running, 0) < DagModel.max_active_runs
)
query = query.order_by(
nulls_first(cls.last_scheduling_decision, session=session),
cls.execution_date,
)
if not settings.ALLOW_FUTURE_EXEC_DATES:
query = query.filter(DagRun.execution_date <= func.now())
return with_row_locks(
query.limit(max_number), of=cls, session=session, **skip_locked(session=session)
)
@classmethod
@provide_session
def find(
cls,
dag_id: str | list[str] | None = None,
run_id: Iterable[str] | None = None,
execution_date: datetime | Iterable[datetime] | None = None,
state: DagRunState | None = None,
external_trigger: bool | None = None,
no_backfills: bool = False,
run_type: DagRunType | None = None,
session: Session = NEW_SESSION,
execution_start_date: datetime | None = None,
execution_end_date: datetime | None = None,
) -> list[DagRun]:
"""
Returns a set of dag runs for the given search criteria.
:param dag_id: the dag_id or list of dag_id to find dag runs for
:param run_id: defines the run id for this dag run
:param run_type: type of DagRun
:param execution_date: the execution date
:param state: the state of the dag run
:param external_trigger: whether this dag run is externally triggered
:param no_backfills: return no backfills (True), return all (False).
Defaults to False
:param session: database session
:param execution_start_date: dag run that was executed from this date
:param execution_end_date: dag run that was executed until this date
"""
qry = session.query(cls)
dag_ids = [dag_id] if isinstance(dag_id, str) else dag_id
if dag_ids:
qry = qry.filter(cls.dag_id.in_(dag_ids))
if is_container(run_id):
qry = qry.filter(cls.run_id.in_(run_id))
elif run_id is not None:
qry = qry.filter(cls.run_id == run_id)
if is_container(execution_date):
qry = qry.filter(cls.execution_date.in_(execution_date))
elif execution_date is not None:
qry = qry.filter(cls.execution_date == execution_date)
if execution_start_date and execution_end_date:
qry = qry.filter(cls.execution_date.between(execution_start_date, execution_end_date))
elif execution_start_date:
qry = qry.filter(cls.execution_date >= execution_start_date)
elif execution_end_date:
qry = qry.filter(cls.execution_date <= execution_end_date)
if state:
qry = qry.filter(cls.state == state)
if external_trigger is not None:
qry = qry.filter(cls.external_trigger == external_trigger)
if run_type:
qry = qry.filter(cls.run_type == run_type)
if no_backfills:
qry = qry.filter(cls.run_type != DagRunType.BACKFILL_JOB)
return qry.order_by(cls.execution_date).all()
@classmethod
@provide_session
def find_duplicate(
cls,
dag_id: str,
run_id: str,
execution_date: datetime,
session: Session = NEW_SESSION,
) -> DagRun | None:
"""
Return an existing run for the DAG with a specific run_id or execution_date.
*None* is returned if no such DAG run is found.
:param dag_id: the dag_id to find duplicates for
:param run_id: defines the run id for this dag run
:param execution_date: the execution date
:param session: database session
"""
return (
session.query(cls)
.filter(
cls.dag_id == dag_id,
or_(cls.run_id == run_id, cls.execution_date == execution_date),
)
.one_or_none()
)
@staticmethod
def generate_run_id(run_type: DagRunType, execution_date: datetime) -> str:
"""Generate Run ID based on Run Type and Execution Date."""
# _Ensure_ run_type is a DagRunType, not just a string from user code
return DagRunType(run_type).generate_run_id(execution_date)
@provide_session
def get_task_instances(
self,
state: Iterable[TaskInstanceState | None] | None = None,
session: Session = NEW_SESSION,
) -> list[TI]:
"""Returns the task instances for this dag run."""
tis = (
session.query(TI)
.options(joinedload(TI.dag_run))
.filter(
TI.dag_id == self.dag_id,
TI.run_id == self.run_id,
)
)
if state:
if isinstance(state, str):
tis = tis.filter(TI.state == state)
else:
# this is required to deal with NULL values
if State.NONE in state:
if all(x is None for x in state):
tis = tis.filter(TI.state.is_(None))
else:
not_none_state = [s for s in state if s]
tis = tis.filter(or_(TI.state.in_(not_none_state), TI.state.is_(None)))
else:
tis = tis.filter(TI.state.in_(state))
if self.dag and self.dag.partial:
tis = tis.filter(TI.task_id.in_(self.dag.task_ids))
return tis.all()
@provide_session
def get_task_instance(
self,
task_id: str,
session: Session = NEW_SESSION,
*,
map_index: int = -1,
) -> TI | None:
"""
Returns the task instance specified by task_id for this dag run.
:param task_id: the task id
:param session: Sqlalchemy ORM Session
"""
return (
session.query(TI)
.filter_by(dag_id=self.dag_id, run_id=self.run_id, task_id=task_id, map_index=map_index)
.one_or_none()
)
def get_dag(self) -> DAG:
"""
Returns the Dag associated with this DagRun.
:return: DAG
"""
if not self.dag:
raise AirflowException(f"The DAG (.dag) for {self} needs to be set")
return self.dag
@provide_session
def get_previous_dagrun(
self, state: DagRunState | None = None, session: Session = NEW_SESSION
) -> DagRun | None:
"""The previous DagRun, if there is one."""
filters = [
DagRun.dag_id == self.dag_id,
DagRun.execution_date < self.execution_date,
]
if state is not None:
filters.append(DagRun.state == state)
return session.query(DagRun).filter(*filters).order_by(DagRun.execution_date.desc()).first()
@provide_session
def get_previous_scheduled_dagrun(self, session: Session = NEW_SESSION) -> DagRun | None:
"""The previous, SCHEDULED DagRun, if there is one."""
return (
session.query(DagRun)
.filter(
DagRun.dag_id == self.dag_id,
DagRun.execution_date < self.execution_date,
DagRun.run_type != DagRunType.MANUAL,
)
.order_by(DagRun.execution_date.desc())
.first()
)
@provide_session
def update_state(
self, session: Session = NEW_SESSION, execute_callbacks: bool = True
) -> tuple[list[TI], DagCallbackRequest | None]:
"""
Determines the overall state of the DagRun based on the state
of its TaskInstances.
:param session: Sqlalchemy ORM Session
:param execute_callbacks: Should dag callbacks (success/failure, SLA etc.) be invoked
directly (default: true) or recorded as a pending request in the ``returned_callback`` property
:return: Tuple containing tis that can be scheduled in the current loop & `returned_callback` that
needs to be executed
"""
# Callback to execute in case of Task Failures
callback: DagCallbackRequest | None = None
class _UnfinishedStates(NamedTuple):
tis: Sequence[TI]
@classmethod
def calculate(cls, unfinished_tis: Sequence[TI]) -> _UnfinishedStates:
return cls(tis=unfinished_tis)
@property
def should_schedule(self) -> bool:
return (
bool(self.tis)
and all(not t.task.depends_on_past for t in self.tis)
and all(t.task.max_active_tis_per_dag is None for t in self.tis)
and all(t.task.max_active_tis_per_dagrun is None for t in self.tis)
and all(t.state != TaskInstanceState.DEFERRED for t in self.tis)
)
def recalculate(self) -> _UnfinishedStates:
return self._replace(tis=[t for t in self.tis if t.state in State.unfinished])
start_dttm = timezone.utcnow()
self.last_scheduling_decision = start_dttm
with Stats.timer(
f"dagrun.dependency-check.{self.dag_id}",
tags=self.stats_tags,
):
dag = self.get_dag()
info = self.task_instance_scheduling_decisions(session)
tis = info.tis
schedulable_tis = info.schedulable_tis
changed_tis = info.changed_tis
finished_tis = info.finished_tis
unfinished = _UnfinishedStates.calculate(info.unfinished_tis)
if unfinished.should_schedule:
are_runnable_tasks = schedulable_tis or changed_tis
# small speed up
if not are_runnable_tasks:
are_runnable_tasks, changed_by_upstream = self._are_premature_tis(
unfinished.tis, finished_tis, session
)
if changed_by_upstream: # Something changed, we need to recalculate!
unfinished = unfinished.recalculate()
leaf_task_ids = {t.task_id for t in dag.leaves}
leaf_tis = [ti for ti in tis if ti.task_id in leaf_task_ids if ti.state != TaskInstanceState.REMOVED]
# TODO: Remove 'getattr' if setup/teardown is available for mapped task
if dag.teardowns:
# when on_failure_fail_dagrun is `False`, the final state of the DagRun
# will be computed as if the teardown task simply didn't exist.
teardown_task_ids = [t.task_id for t in dag.teardowns]
upstream_of_teardowns = [t.task_id for t in dag.tasks_upstream_of_teardowns]
teardown_tis = [ti for ti in tis if ti.task_id in teardown_task_ids]
on_failure_fail_tis = [ti for ti in teardown_tis if getattr(ti.task, "on_failure_fail_dagrun")]
tis_upstream_of_teardowns = [ti for ti in tis if ti.task_id in upstream_of_teardowns]
leaf_tis = list(set(leaf_tis) - set(teardown_tis))
leaf_tis.extend(on_failure_fail_tis)
leaf_tis.extend(tis_upstream_of_teardowns)
# if all roots finished and at least one failed, the run failed
if not unfinished.tis and any(leaf_ti.state in State.failed_states for leaf_ti in leaf_tis):
self.log.error("Marking run %s failed", self)
self.set_state(DagRunState.FAILED)
self.notify_dagrun_state_changed(msg="task_failure")
if execute_callbacks:
dag.handle_callback(self, success=False, reason="task_failure", session=session)
elif dag.has_on_failure_callback:
from airflow.models.dag import DagModel
dag_model = DagModel.get_dagmodel(dag.dag_id, session)
callback = DagCallbackRequest(
full_filepath=dag.fileloc,
dag_id=self.dag_id,
run_id=self.run_id,
is_failure_callback=True,
processor_subdir=None if dag_model is None else dag_model.processor_subdir,
msg="task_failure",
)
# if all leaves succeeded and no unfinished tasks, the run succeeded
elif not unfinished.tis and all(leaf_ti.state in State.success_states for leaf_ti in leaf_tis):
self.log.info("Marking run %s successful", self)
self.set_state(DagRunState.SUCCESS)
self.notify_dagrun_state_changed(msg="success")
if execute_callbacks:
dag.handle_callback(self, success=True, reason="success", session=session)
elif dag.has_on_success_callback:
from airflow.models.dag import DagModel
dag_model = DagModel.get_dagmodel(dag.dag_id, session)
callback = DagCallbackRequest(
full_filepath=dag.fileloc,
dag_id=self.dag_id,
run_id=self.run_id,
is_failure_callback=False,
processor_subdir=None if dag_model is None else dag_model.processor_subdir,
msg="success",
)
# if *all tasks* are deadlocked, the run failed
elif unfinished.should_schedule and not are_runnable_tasks:
self.log.error("Task deadlock (no runnable tasks); marking run %s failed", self)
self.set_state(DagRunState.FAILED)
self.notify_dagrun_state_changed(msg="all_tasks_deadlocked")
if execute_callbacks:
dag.handle_callback(self, success=False, reason="all_tasks_deadlocked", session=session)
elif dag.has_on_failure_callback:
from airflow.models.dag import DagModel
dag_model = DagModel.get_dagmodel(dag.dag_id, session)
callback = DagCallbackRequest(
full_filepath=dag.fileloc,
dag_id=self.dag_id,
run_id=self.run_id,
is_failure_callback=True,
processor_subdir=None if dag_model is None else dag_model.processor_subdir,
msg="all_tasks_deadlocked",
)
# finally, if the roots aren't done, the dag is still running
else:
self.set_state(DagRunState.RUNNING)
if self._state == DagRunState.FAILED or self._state == DagRunState.SUCCESS:
msg = (
"DagRun Finished: dag_id=%s, execution_date=%s, run_id=%s, "
"run_start_date=%s, run_end_date=%s, run_duration=%s, "
"state=%s, external_trigger=%s, run_type=%s, "
"data_interval_start=%s, data_interval_end=%s, dag_hash=%s"
)
self.log.info(
msg,
self.dag_id,
self.execution_date,
self.run_id,
self.start_date,
self.end_date,
(self.end_date - self.start_date).total_seconds()
if self.start_date and self.end_date
else None,
self._state,
self.external_trigger,
self.run_type,
self.data_interval_start,
self.data_interval_end,
self.dag_hash,
)
session.flush()
self._emit_true_scheduling_delay_stats_for_finished_state(finished_tis)
self._emit_duration_stats_for_finished_state()
session.merge(self)
# We do not flush here for performance reasons(It increases queries count by +20)
return schedulable_tis, callback
@provide_session
def task_instance_scheduling_decisions(self, session: Session = NEW_SESSION) -> TISchedulingDecision:
tis = self.get_task_instances(session=session, state=State.task_states)
self.log.debug("number of tis tasks for %s: %s task(s)", self, len(tis))
def _filter_tis_and_exclude_removed(dag: DAG, tis: list[TI]) -> Iterable[TI]:
"""Populate ``ti.task`` while excluding those missing one, marking them as REMOVED."""
for ti in tis:
try:
ti.task = dag.get_task(ti.task_id)
except TaskNotFound:
if ti.state != State.REMOVED:
self.log.error("Failed to get task for ti %s. Marking it as removed.", ti)
ti.state = State.REMOVED
session.flush()
else:
yield ti
tis = list(_filter_tis_and_exclude_removed(self.get_dag(), tis))
unfinished_tis = [t for t in tis if t.state in State.unfinished]
finished_tis = [t for t in tis if t.state in State.finished]
if unfinished_tis:
schedulable_tis = [ut for ut in unfinished_tis if ut.state in SCHEDULEABLE_STATES]
self.log.debug("number of scheduleable tasks for %s: %s task(s)", self, len(schedulable_tis))
schedulable_tis, changed_tis, expansion_happened = self._get_ready_tis(
schedulable_tis,
finished_tis,
session=session,
)
# During expansion, we may change some tis into non-schedulable
# states, so we need to re-compute.
if expansion_happened:
changed_tis = True
new_unfinished_tis = [t for t in unfinished_tis if t.state in State.unfinished]
finished_tis.extend(t for t in unfinished_tis if t.state in State.finished)
unfinished_tis = new_unfinished_tis
else:
schedulable_tis = []
changed_tis = False
return TISchedulingDecision(
tis=tis,
schedulable_tis=schedulable_tis,
changed_tis=changed_tis,
unfinished_tis=unfinished_tis,
finished_tis=finished_tis,
)
def notify_dagrun_state_changed(self, msg: str = ""):
if self.state == DagRunState.RUNNING:
get_listener_manager().hook.on_dag_run_running(dag_run=self, msg=msg)
elif self.state == DagRunState.SUCCESS:
get_listener_manager().hook.on_dag_run_success(dag_run=self, msg=msg)
elif self.state == DagRunState.FAILED:
get_listener_manager().hook.on_dag_run_failed(dag_run=self, msg=msg)
# deliberately not notifying on QUEUED
# we can't get all the state changes on SchedulerJob, BackfillJob
# or LocalTaskJob, so we don't want to "falsely advertise" we notify about that
def _get_ready_tis(
self,
schedulable_tis: list[TI],
finished_tis: list[TI],
session: Session,
) -> tuple[list[TI], bool, bool]:
old_states = {}
ready_tis: list[TI] = []
changed_tis = False
if not schedulable_tis:
return ready_tis, changed_tis, False
# If we expand TIs, we need a new list so that we iterate over them too. (We can't alter
# `schedulable_tis` in place and have the `for` loop pick them up
additional_tis: list[TI] = []
dep_context = DepContext(
flag_upstream_failed=True,
ignore_unmapped_tasks=True, # Ignore this Dep, as we will expand it if we can.
finished_tis=finished_tis,
)
def _expand_mapped_task_if_needed(ti: TI) -> Iterable[TI] | None:
"""Try to expand the ti, if needed.
If the ti needs expansion, newly created task instances are
returned as well as the original ti.
The original ti is also modified in-place and assigned the
``map_index`` of 0.
If the ti does not need expansion, either because the task is not
mapped, or has already been expanded, *None* is returned.
"""
if ti.map_index >= 0: # Already expanded, we're good.
return None
from airflow.models.mappedoperator import MappedOperator
if isinstance(ti.task, MappedOperator):
# If we get here, it could be that we are moving from non-mapped to mapped
# after task instance clearing or this ti is not yet expanded. Safe to clear
# the db references.
ti.clear_db_references(session=session)
try:
expanded_tis, _ = ti.task.expand_mapped_task(self.run_id, session=session)
except NotMapped: # Not a mapped task, nothing needed.
return None
if expanded_tis:
return expanded_tis
return ()
# Check dependencies.
expansion_happened = False
# Set of task ids for which was already done _revise_map_indexes_if_mapped
revised_map_index_task_ids = set()
for schedulable in itertools.chain(schedulable_tis, additional_tis):
old_state = schedulable.state
if not schedulable.are_dependencies_met(session=session, dep_context=dep_context):
old_states[schedulable.key] = old_state
continue
# If schedulable is not yet expanded, try doing it now. This is
# called in two places: First and ideally in the mini scheduler at
# the end of LocalTaskJob, and then as an "expansion of last resort"
# in the scheduler to ensure that the mapped task is correctly
# expanded before executed. Also see _revise_map_indexes_if_mapped
# docstring for additional information.
new_tis = None
if schedulable.map_index < 0:
new_tis = _expand_mapped_task_if_needed(schedulable)
if new_tis is not None:
additional_tis.extend(new_tis)
expansion_happened = True
if new_tis is None and schedulable.state in SCHEDULEABLE_STATES:
# It's enough to revise map index once per task id,
# checking the map index for each mapped task significantly slows down scheduling
if schedulable.task.task_id not in revised_map_index_task_ids:
ready_tis.extend(self._revise_map_indexes_if_mapped(schedulable.task, session=session))
revised_map_index_task_ids.add(schedulable.task.task_id)
ready_tis.append(schedulable)
# Check if any ti changed state
tis_filter = TI.filter_for_tis(old_states)
if tis_filter is not None:
fresh_tis = session.query(TI).filter(tis_filter).all()
changed_tis = any(ti.state != old_states[ti.key] for ti in fresh_tis)
return ready_tis, changed_tis, expansion_happened
def _are_premature_tis(
self,
unfinished_tis: Sequence[TI],
finished_tis: list[TI],
session: Session,
) -> tuple[bool, bool]:
dep_context = DepContext(
flag_upstream_failed=True,
ignore_in_retry_period=True,
ignore_in_reschedule_period=True,
finished_tis=finished_tis,
)
# there might be runnable tasks that are up for retry and for some reason(retry delay, etc.) are
# not ready yet, so we set the flags to count them in
return (
any(ut.are_dependencies_met(dep_context=dep_context, session=session) for ut in unfinished_tis),
dep_context.have_changed_ti_states,
)
def _emit_true_scheduling_delay_stats_for_finished_state(self, finished_tis: list[TI]) -> None:
"""Emit the true scheduling delay stats.
The true scheduling delay stats is defined as the time when the first
task in DAG starts minus the expected DAG run datetime.
This helper method is used in ``update_state`` when the state of the
DAG run is updated to a completed status (either success or failure).
It finds the first started task within the DAG, calculates the run's
expected start time based on the logical date and timetable, and gets
the delay from the difference of these two values.
The emitted data may contain outliers (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 outliers on the stats side through dashboards tooling.
Note that the stat will only be emitted for scheduler-triggered DAG runs
(i.e. when ``external_trigger`` is *False*).
"""
if self.state == TaskInstanceState.RUNNING:
return
if self.external_trigger:
return
if not finished_tis:
return
try:
dag = self.get_dag()
if not dag.timetable.periodic:
# We can't emit this metric if there is no following schedule to calculate from!
return
try:
first_start_date = min(ti.start_date for ti in finished_tis if ti.start_date)
except ValueError: # No start dates at all.
pass
else:
# TODO: Logically, this should be DagRunInfo.run_after, but the
# information is not stored on a DagRun, only before the actual
# execution on DagModel.next_dagrun_create_after. We should add
# a field on DagRun for this instead of relying on the run
# always happening immediately after the data interval.
data_interval_end = dag.get_run_data_interval(self).end
true_delay = first_start_date - data_interval_end
if true_delay.total_seconds() > 0:
Stats.timing(
f"dagrun.{dag.dag_id}.first_task_scheduling_delay", true_delay, tags=self.stats_tags
)
Stats.timing("dagrun.first_task_scheduling_delay", true_delay, tags=self.stats_tags)
except Exception:
self.log.warning("Failed to record first_task_scheduling_delay metric:", exc_info=True)
def _emit_duration_stats_for_finished_state(self):
if self.state == State.RUNNING:
return
if self.start_date is None:
self.log.warning("Failed to record duration of %s: start_date is not set.", self)
return
if self.end_date is None:
self.log.warning("Failed to record duration of %s: end_date is not set.", self)
return
duration = self.end_date - self.start_date
timer_params = {"dt": duration, "tags": self.stats_tags}
Stats.timing(f"dagrun.duration.{self.state.value}.{self.dag_id}", **timer_params)
Stats.timing(f"dagrun.duration.{self.state.value}", **timer_params)
@provide_session
def verify_integrity(self, *, session: Session = NEW_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.
:missing_indexes: A dictionary of task vs indexes that are missing.
:param session: Sqlalchemy ORM Session
"""
from airflow.settings import task_instance_mutation_hook
# Set for the empty default in airflow.settings -- if it's not set this means it has been changed
# Note: Literal[True, False] instead of bool because otherwise it doesn't correctly find the overload.
hook_is_noop: Literal[True, False] = getattr(task_instance_mutation_hook, "is_noop", False)
dag = self.get_dag()
task_ids = self._check_for_removed_or_restored_tasks(
dag, task_instance_mutation_hook, session=session
)
def task_filter(task: Operator) -> bool:
return task.task_id not in task_ids and (
self.is_backfill
or task.start_date <= self.execution_date
and (task.end_date is None or self.execution_date <= task.end_date)
)
created_counts: dict[str, int] = defaultdict(int)
task_creator = self._get_task_creator(created_counts, task_instance_mutation_hook, hook_is_noop)
# Create the missing tasks, including mapped tasks
tasks_to_create = (task for task in dag.task_dict.values() if task_filter(task))
tis_to_create = self._create_tasks(tasks_to_create, task_creator, session=session)
self._create_task_instances(self.dag_id, tis_to_create, created_counts, hook_is_noop, session=session)
def _check_for_removed_or_restored_tasks(
self, dag: DAG, ti_mutation_hook, *, session: Session
) -> set[str]:
"""
Check for removed tasks/restored/missing tasks.
:param dag: DAG object corresponding to the dagrun
:param ti_mutation_hook: task_instance_mutation_hook function
:param session: Sqlalchemy ORM Session
:return: Task IDs in the DAG run
"""
tis = self.get_task_instances(session=session)
# check for removed or restored tasks
task_ids = set()
for ti in tis:
ti_mutation_hook(ti)
task_ids.add(ti.task_id)
try:
task = dag.get_task(ti.task_id)
should_restore_task = (task is not None) and ti.state == State.REMOVED
if should_restore_task:
self.log.info("Restoring task '%s' which was previously removed from DAG '%s'", ti, dag)
Stats.incr(f"task_restored_to_dag.{dag.dag_id}", tags=self.stats_tags)
ti.state = State.NONE
except AirflowException:
if ti.state == State.REMOVED:
pass # ti has already been removed, just ignore it
elif self.state != State.RUNNING and not dag.partial:
self.log.warning("Failed to get task '%s' for dag '%s'. Marking it as removed.", ti, dag)
Stats.incr(f"task_removed_from_dag.{dag.dag_id}", tags=self.stats_tags)
ti.state = State.REMOVED
continue
try:
num_mapped_tis = task.get_parse_time_mapped_ti_count()
except NotMapped:
continue
except NotFullyPopulated:
# What if it is _now_ dynamically mapped, but wasn't before?
try:
total_length = task.get_mapped_ti_count(self.run_id, session=session)
except NotFullyPopulated:
# Not all upstreams finished, so we can't tell what should be here. Remove everything.
if ti.map_index >= 0:
self.log.debug(
"Removing the unmapped TI '%s' as the mapping can't be resolved yet", ti
)
ti.state = State.REMOVED
continue
# Upstreams finished, check there aren't any extras
if ti.map_index >= total_length:
self.log.debug(
"Removing task '%s' as the map_index is longer than the resolved mapping list (%d)",
ti,
total_length,
)
ti.state = State.REMOVED
else:
# Check if the number of mapped literals has changed, and we need to mark this TI as removed.
if ti.map_index >= num_mapped_tis:
self.log.debug(
"Removing task '%s' as the map_index is longer than the literal mapping list (%s)",
ti,
num_mapped_tis,
)
ti.state = State.REMOVED
elif ti.map_index < 0:
self.log.debug("Removing the unmapped TI '%s' as the mapping can now be performed", ti)
ti.state = State.REMOVED
return task_ids
@overload
def _get_task_creator(
self,
created_counts: dict[str, int],
ti_mutation_hook: Callable,
hook_is_noop: Literal[True],
) -> Callable[[Operator, Iterable[int]], Iterator[dict[str, Any]]]:
...
@overload
def _get_task_creator(
self,
created_counts: dict[str, int],
ti_mutation_hook: Callable,
hook_is_noop: Literal[False],
) -> Callable[[Operator, Iterable[int]], Iterator[TI]]:
...
def _get_task_creator(
self,
created_counts: dict[str, int],
ti_mutation_hook: Callable,
hook_is_noop: Literal[True, False],
) -> Callable[[Operator, Iterable[int]], Iterator[dict[str, Any]] | Iterator[TI]]:
"""
Get the task creator function.
This function also updates the created_counts dictionary with the number of tasks created.
:param created_counts: Dictionary of task_type -> count of created TIs
:param ti_mutation_hook: task_instance_mutation_hook function
:param hook_is_noop: Whether the task_instance_mutation_hook is a noop
"""
if hook_is_noop:
def create_ti_mapping(task: Operator, indexes: Iterable[int]) -> Iterator[dict[str, Any]]:
created_counts[task.task_type] += 1
for map_index in indexes:
yield TI.insert_mapping(self.run_id, task, map_index=map_index)
creator = create_ti_mapping
else:
def create_ti(task: Operator, indexes: Iterable[int]) -> Iterator[TI]:
for map_index in indexes:
ti = TI(task, run_id=self.run_id, map_index=map_index)
ti_mutation_hook(ti)
created_counts[ti.operator] += 1
yield ti
creator = create_ti
return creator
def _create_tasks(
self,
tasks: Iterable[Operator],
task_creator: TaskCreator,
*,
session: Session,
) -> CreatedTasks:
"""
Create missing tasks -- and expand any MappedOperator that _only_ have literals as input.
:param tasks: Tasks to create jobs for in the DAG run
:param task_creator: Function to create task instances
"""
map_indexes: Iterable[int]
for task in tasks:
try:
count = task.get_mapped_ti_count(self.run_id, session=session)
except (NotMapped, NotFullyPopulated):
map_indexes = (-1,)
else:
if count:
map_indexes = range(count)
else:
# Make sure to always create at least one ti; this will be
# marked as REMOVED later at runtime.
map_indexes = (-1,)
yield from task_creator(task, map_indexes)
def _create_task_instances(
self,
dag_id: str,
tasks: Iterator[dict[str, Any]] | Iterator[TI],
created_counts: dict[str, int],
hook_is_noop: bool,
*,
session: Session,
) -> None:
"""
Create the necessary task instances from the given tasks.
:param dag_id: DAG ID associated with the dagrun
:param tasks: the tasks to create the task instances from
:param created_counts: a dictionary of number of tasks -> total ti created by the task creator
:param hook_is_noop: whether the task_instance_mutation_hook is noop
:param session: the session to use
"""
# Fetch the information we need before handling the exception to avoid
# PendingRollbackError due to the session being invalidated on exception
# see https://github.com/apache/superset/pull/530
run_id = self.run_id
try:
if hook_is_noop:
session.bulk_insert_mappings(TI, tasks)
else:
session.bulk_save_objects(tasks)
for task_type, count in created_counts.items():
Stats.incr(f"task_instance_created-{task_type}", count, tags=self.stats_tags)
session.flush()
except IntegrityError:
self.log.info(
"Hit IntegrityError while creating the TIs for %s- %s",
dag_id,
run_id,
exc_info=True,
)
self.log.info("Doing session rollback.")
# TODO[HA]: We probably need to savepoint this so we can keep the transaction alive.
session.rollback()
def _revise_map_indexes_if_mapped(self, task: Operator, *, session: Session) -> Iterator[TI]:
"""Check if task increased or reduced in length and handle appropriately.
Task instances that do not already exist are created and returned if
possible. Expansion only happens if all upstreams are ready; otherwise
we delay expansion to the "last resort". See comments at the call site
for more details.
"""
from airflow.settings import task_instance_mutation_hook
try:
total_length = task.get_mapped_ti_count(self.run_id, session=session)
except NotMapped:
return # Not a mapped task, don't need to do anything.
except NotFullyPopulated:
return # Upstreams not ready, don't need to revise this yet.
query = session.query(TI.map_index).filter(
TI.dag_id == self.dag_id,
TI.task_id == task.task_id,
TI.run_id == self.run_id,
)
existing_indexes = {i for (i,) in query}
removed_indexes = existing_indexes.difference(range(total_length))
if removed_indexes:
session.query(TI).filter(
TI.dag_id == self.dag_id,
TI.task_id == task.task_id,
TI.run_id == self.run_id,
TI.map_index.in_(removed_indexes),
).update({TI.state: TaskInstanceState.REMOVED})
session.flush()
for index in range(total_length):
if index in existing_indexes:
continue
ti = TI(task, run_id=self.run_id, map_index=index, state=None)
self.log.debug("Expanding TIs upserted %s", ti)
task_instance_mutation_hook(ti)
ti = session.merge(ti)
ti.refresh_from_task(task)
session.flush()
yield ti
@staticmethod
def get_run(session: Session, dag_id: str, execution_date: datetime) -> DagRun | None:
"""
Get a single DAG Run.
:meta private:
:param session: Sqlalchemy ORM Session
:param dag_id: DAG ID
:param execution_date: execution date
:return: DagRun corresponding to the given dag_id and execution date
if one exists. None otherwise.
"""
warnings.warn(
"This method is deprecated. Please use SQLAlchemy directly",
RemovedInAirflow3Warning,
stacklevel=2,
)
return (
session.query(DagRun)
.filter(
DagRun.dag_id == dag_id,
DagRun.external_trigger == False, # noqa
DagRun.execution_date == execution_date,
)
.first()
)
@property
def is_backfill(self) -> bool:
return self.run_type == DagRunType.BACKFILL_JOB
@classmethod
@provide_session
def get_latest_runs(cls, session: Session = NEW_SESSION) -> list[DagRun]:
"""Returns the latest DagRun for each DAG."""
subquery = (
session.query(cls.dag_id, func.max(cls.execution_date).label("execution_date"))
.group_by(cls.dag_id)
.subquery()
)
return (
session.query(cls)
.join(
subquery,
and_(cls.dag_id == subquery.c.dag_id, cls.execution_date == subquery.c.execution_date),
)
.all()
)
@provide_session
def schedule_tis(
self,
schedulable_tis: Iterable[TI],
session: Session = NEW_SESSION,
max_tis_per_query: int | None = None,
) -> int:
"""
Set the given task instances in to the scheduled state.
Each element of ``schedulable_tis`` should have it's ``task`` attribute already set.
Any EmptyOperator without callbacks or outlets is instead set straight to the success state.
All the TIs should belong to this DagRun, but this code is in the hot-path, this is not checked -- it
is the caller's responsibility to call this function only with TIs from a single dag run.
"""
# Get list of TI IDs that do not need to executed, these are
# tasks using EmptyOperator and without on_execute_callback / on_success_callback
dummy_ti_ids = []
schedulable_ti_ids = []
for ti in schedulable_tis:
if (
ti.task.inherits_from_empty_operator
and not ti.task.on_execute_callback
and not ti.task.on_success_callback
and not ti.task.outlets
):
dummy_ti_ids.append(ti.task_id)
else:
schedulable_ti_ids.append((ti.task_id, ti.map_index))
count = 0
if schedulable_ti_ids:
schedulable_ti_ids_chunks = chunks(
schedulable_ti_ids, max_tis_per_query or len(schedulable_ti_ids)
)
for schedulable_ti_ids_chunk in schedulable_ti_ids_chunks:
count += (
session.query(TI)
.filter(
TI.dag_id == self.dag_id,
TI.run_id == self.run_id,
tuple_in_condition((TI.task_id, TI.map_index), schedulable_ti_ids_chunk),
)
.update({TI.state: State.SCHEDULED}, synchronize_session=False)
)
# Tasks using EmptyOperator should not be executed, mark them as success
if dummy_ti_ids:
dummy_ti_ids_chunks = chunks(dummy_ti_ids, max_tis_per_query or len(dummy_ti_ids))
for dummy_ti_ids_chunk in dummy_ti_ids_chunks:
count += (
session.query(TI)
.filter(
TI.dag_id == self.dag_id,
TI.run_id == self.run_id,
TI.task_id.in_(dummy_ti_ids_chunk),
)
.update(
{
TI.state: State.SUCCESS,
TI.start_date: timezone.utcnow(),
TI.end_date: timezone.utcnow(),
TI.duration: 0,
},
synchronize_session=False,
)
)
return count
@provide_session
def get_log_template(self, *, session: Session = NEW_SESSION) -> LogTemplate:
if self.log_template_id is None: # DagRun created before LogTemplate introduction.
template = session.query(LogTemplate).order_by(LogTemplate.id).first()
else:
template = session.get(LogTemplate, self.log_template_id)
if template is None:
raise AirflowException(
f"No log_template entry found for ID {self.log_template_id!r}. "
f"Please make sure you set up the metadatabase correctly."
)
return template
@provide_session
def get_log_filename_template(self, *, session: Session = NEW_SESSION) -> str:
warnings.warn(
"This method is deprecated. Please use get_log_template instead.",
RemovedInAirflow3Warning,
stacklevel=2,
)
return self.get_log_template(session=session).filename
class DagRunNote(Base):
"""For storage of arbitrary notes concerning the dagrun instance."""
__tablename__ = "dag_run_note"
user_id = Column(Integer, nullable=True)
dag_run_id = Column(Integer, primary_key=True, nullable=False)
content = Column(String(1000).with_variant(Text(1000), "mysql"))
created_at = Column(UtcDateTime, default=timezone.utcnow, nullable=False)
updated_at = Column(UtcDateTime, default=timezone.utcnow, onupdate=timezone.utcnow, nullable=False)
dag_run = relationship("DagRun", back_populates="dag_run_note")
__table_args__ = (
PrimaryKeyConstraint("dag_run_id", name="dag_run_note_pkey"),
ForeignKeyConstraint(
(dag_run_id,),
["dag_run.id"],
name="dag_run_note_dr_fkey",
ondelete="CASCADE",
),
ForeignKeyConstraint(
(user_id,),
["ab_user.id"],
name="dag_run_note_user_fkey",
),
)
def __init__(self, content, user_id=None):
self.content = content
self.user_id = user_id
def __repr__(self):
prefix = f"<{self.__class__.__name__}: {self.dag_id}.{self.dagrun_id} {self.run_id}"
if self.map_index != -1:
prefix += f" map_index={self.map_index}"
return prefix + ">"