Source code for airflow.models.taskinstance

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# to you under the Apache License, Version 2.0 (the
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import contextlib
import hashlib
import logging
import math
import os
import pickle
import signal
import warnings
from collections import defaultdict
from datetime import datetime, timedelta
from functools import partial
from tempfile import NamedTemporaryFile
from typing import IO, TYPE_CHECKING, Any, Callable, Dict, Iterable, List, NamedTuple, Optional, Tuple, Union
from urllib.parse import quote

import dill
import jinja2
import lazy_object_proxy
import pendulum
from jinja2 import TemplateAssertionError, UndefinedError
from sqlalchemy import (
    Column,
    Float,
    ForeignKeyConstraint,
    Index,
    Integer,
    PickleType,
    String,
    and_,
    func,
    inspect,
    or_,
    tuple_,
)
from sqlalchemy.ext.associationproxy import association_proxy
from sqlalchemy.orm import reconstructor, relationship
from sqlalchemy.orm.attributes import NO_VALUE, set_committed_value
from sqlalchemy.orm.session import Session
from sqlalchemy.sql.elements import BooleanClauseList
from sqlalchemy.sql.sqltypes import BigInteger

from airflow import settings
from airflow.compat.functools import cache
from airflow.configuration import conf
from airflow.exceptions import (
    AirflowException,
    AirflowFailException,
    AirflowNotFoundException,
    AirflowRescheduleException,
    AirflowSensorTimeout,
    AirflowSkipException,
    AirflowSmartSensorException,
    AirflowTaskTimeout,
    DagRunNotFound,
    TaskDeferralError,
    TaskDeferred,
)
from airflow.models.base import COLLATION_ARGS, ID_LEN, Base
from airflow.models.connection import Connection
from airflow.models.log import Log
from airflow.models.param import ParamsDict
from airflow.models.taskfail import TaskFail
from airflow.models.taskreschedule import TaskReschedule
from airflow.models.variable import Variable
from airflow.models.xcom import XCOM_RETURN_KEY, XCom
from airflow.plugins_manager import integrate_macros_plugins
from airflow.sentry import Sentry
from airflow.stats import Stats
from airflow.ti_deps.dep_context import DepContext
from airflow.ti_deps.dependencies_deps import REQUEUEABLE_DEPS, RUNNING_DEPS
from airflow.timetables.base import DataInterval
from airflow.typing_compat import Literal
from airflow.utils import timezone
from airflow.utils.email import send_email
from airflow.utils.helpers import is_container
from airflow.utils.log.logging_mixin import LoggingMixin
from airflow.utils.net import get_hostname
from airflow.utils.operator_helpers import context_to_airflow_vars
from airflow.utils.platform import getuser
from airflow.utils.session import create_session, provide_session
from airflow.utils.sqlalchemy import ExtendedJSON, UtcDateTime
from airflow.utils.state import DagRunState, State
from airflow.utils.timeout import timeout

try:
    from kubernetes.client.api_client import ApiClient

    from airflow.kubernetes.kube_config import KubeConfig
    from airflow.kubernetes.pod_generator import PodGenerator
except ImportError:
[docs]    ApiClient = None

[docs]TR = TaskReschedule
[docs]Context = Dict[str, Any]

_CURRENT_CONTEXT: List[Context] = []
[docs]log = logging.getLogger(__name__)


if TYPE_CHECKING:
    from airflow.models.dag import DAG, DagModel, DagRun


@contextlib.contextmanager
[docs]def set_current_context(context: Context):
    """
    Sets the current execution context to the provided context object.
    This method should be called once per Task execution, before calling operator.execute.
    """
    _CURRENT_CONTEXT.append(context)
    try:
        yield context
    finally:
        expected_state = _CURRENT_CONTEXT.pop()
        if expected_state != context:
            log.warning(
                "Current context is not equal to the state at context stack. Expected=%s, got=%s",
                context,
                expected_state,
            )


[docs]def load_error_file(fd: IO[bytes]) -> Optional[Union[str, Exception]]:
    """Load and return error from error file"""
    if fd.closed:
        return None
    fd.seek(0, os.SEEK_SET)
    data = fd.read()
    if not data:
        return None
    try:
        return pickle.loads(data)
    except Exception:
        return "Failed to load task run error"


[docs]def set_error_file(error_file: str, error: Union[str, Exception]) -> None:
    """Write error into error file by path"""
    with open(error_file, "wb") as fd:
        try:
            pickle.dump(error, fd)
        except Exception:
            # local class objects cannot be pickled, so we fallback
            # to store the string representation instead
            pickle.dump(str(error), fd)


[docs]def clear_task_instances(
    tis,
    session,
    activate_dag_runs=None,
    dag=None,
    dag_run_state: Union[DagRunState, Literal[False]] = DagRunState.QUEUED,
):
    """
    Clears a set of task instances, but makes sure the running ones
    get killed.

    :param tis: a list of task instances
    :param session: current session
    :param dag_run_state: state to set DagRun to. If set to False, dagrun state will not
        be changed.
    :param dag: DAG object
    :param activate_dag_runs: Deprecated parameter, do not pass
    """
    job_ids = []
    task_id_by_key = defaultdict(lambda: defaultdict(lambda: defaultdict(set)))
    for ti in tis:
        if ti.state == State.RUNNING:
            if ti.job_id:
                # If a task is cleared when running, set its state to RESTARTING so that
                # the task is terminated and becomes eligible for retry.
                ti.state = State.RESTARTING
                job_ids.append(ti.job_id)
        else:
            task_id = ti.task_id
            if dag and dag.has_task(task_id):
                task = dag.get_task(task_id)
                ti.refresh_from_task(task)
                task_retries = task.retries
                ti.max_tries = ti.try_number + task_retries - 1
            else:
                # Ignore errors when updating max_tries if dag is None or
                # task not found in dag since database records could be
                # outdated. We make max_tries the maximum value of its
                # original max_tries or the last attempted try number.
                ti.max_tries = max(ti.max_tries, ti.prev_attempted_tries)
            ti.state = State.NONE
            ti.external_executor_id = None
            session.merge(ti)

        task_id_by_key[ti.dag_id][ti.run_id][ti.try_number].add(ti.task_id)

    if task_id_by_key:
        # Clear all reschedules related to the ti to clear

        # This is an optimization for the common case where all tis are for a small number
        # of dag_id, run_id and try_number. Use a nested dict of dag_id,
        # run_id, try_number and task_id to construct the where clause in a
        # hierarchical manner. This speeds up the delete statement by more than 40x for
        # large number of tis (50k+).
        conditions = or_(
            and_(
                TR.dag_id == dag_id,
                or_(
                    and_(
                        TR.run_id == run_id,
                        or_(
                            and_(TR.try_number == try_number, TR.task_id.in_(task_ids))
                            for try_number, task_ids in task_tries.items()
                        ),
                    )
                    for run_id, task_tries in run_ids.items()
                ),
            )
            for dag_id, run_ids in task_id_by_key.items()
        )

        delete_qry = TR.__table__.delete().where(conditions)
        session.execute(delete_qry)

    if job_ids:
        from airflow.jobs.base_job import BaseJob

        for job in session.query(BaseJob).filter(BaseJob.id.in_(job_ids)).all():
            job.state = State.RESTARTING

    if activate_dag_runs is not None:
        warnings.warn(
            "`activate_dag_runs` parameter to clear_task_instances function is deprecated. "
            "Please use `dag_run_state`",
            DeprecationWarning,
            stacklevel=2,
        )
        if not activate_dag_runs:
            dag_run_state = False

    if dag_run_state is not False and tis:
        from airflow.models.dagrun import DagRun  # Avoid circular import

        run_ids_by_dag_id = defaultdict(set)
        for instance in tis:
            run_ids_by_dag_id[instance.dag_id].add(instance.run_id)

        drs = (
            session.query(DagRun)
            .filter(
                or_(
                    and_(DagRun.dag_id == dag_id, DagRun.run_id.in_(run_ids))
                    for dag_id, run_ids in run_ids_by_dag_id.items()
                )
            )
            .all()
        )
        for dr in drs:
            dr.state = dag_run_state
            dr.start_date = timezone.utcnow()
            if dag_run_state == State.QUEUED:
                dr.last_scheduling_decision = None
                dr.start_date = None


[docs]class TaskInstanceKey(NamedTuple):
    """Key used to identify task instance."""

[docs]    dag_id: str
[docs]    task_id: str
[docs]    run_id: str
[docs]    try_number: int = 1

    @property
[docs]    def primary(self) -> Tuple[str, str, str]:
        """Return task instance primary key part of the key"""
        return self.dag_id, self.task_id, self.run_id

    @property
[docs]    def reduced(self) -> 'TaskInstanceKey':
        """Remake the key by subtracting 1 from try number to match in memory information"""
        return TaskInstanceKey(self.dag_id, self.task_id, self.run_id, max(1, self.try_number - 1))

[docs]    def with_try_number(self, try_number: int) -> 'TaskInstanceKey':
        """Returns TaskInstanceKey with provided ``try_number``"""
        return TaskInstanceKey(self.dag_id, self.task_id, self.run_id, try_number)

    @property
[docs]    def key(self) -> "TaskInstanceKey":
        """For API-compatibly with TaskInstance.

        Returns self
        """
        return self


[docs]class TaskInstance(Base, LoggingMixin):
    """
    Task instances store the state of a task instance. This table is the
    authority and single source of truth around what tasks have run and the
    state they are in.

    The SqlAlchemy model doesn't have a SqlAlchemy foreign key to the task or
    dag model deliberately to have more control over transactions.

    Database transactions on this table should insure double triggers and
    any confusion around what task instances are or aren't ready to run
    even while multiple schedulers may be firing task instances.
    """

[docs]    __tablename__ = "task_instance"

[docs]    task_id = Column(String(ID_LEN, **COLLATION_ARGS), primary_key=True, nullable=False)
[docs]    dag_id = Column(String(ID_LEN, **COLLATION_ARGS), primary_key=True, nullable=False)
[docs]    run_id = Column(String(ID_LEN, **COLLATION_ARGS), primary_key=True, nullable=False)
[docs]    start_date = Column(UtcDateTime)
[docs]    end_date = Column(UtcDateTime)
[docs]    duration = Column(Float)
[docs]    state = Column(String(20))
    _try_number = Column('try_number', Integer, default=0)
[docs]    max_tries = Column(Integer)
[docs]    hostname = Column(String(1000))
[docs]    unixname = Column(String(1000))
[docs]    job_id = Column(Integer)
[docs]    pool = Column(String(256), nullable=False)
[docs]    pool_slots = Column(Integer, default=1, nullable=False)
[docs]    queue = Column(String(256))
[docs]    priority_weight = Column(Integer)
[docs]    operator = Column(String(1000))
[docs]    queued_dttm = Column(UtcDateTime)
[docs]    queued_by_job_id = Column(Integer)
[docs]    pid = Column(Integer)
[docs]    executor_config = Column(PickleType(pickler=dill))

[docs]    external_executor_id = Column(String(ID_LEN, **COLLATION_ARGS))

    # The trigger to resume on if we are in state DEFERRED
[docs]    trigger_id = Column(BigInteger)

    # Optional timeout datetime for the trigger (past this, we'll fail)
[docs]    trigger_timeout = Column(UtcDateTime)

    # The method to call next, and any extra arguments to pass to it.
    # Usually used when resuming from DEFERRED.
[docs]    next_method = Column(String(1000))
[docs]    next_kwargs = Column(ExtendedJSON)

    # If adding new fields here then remember to add them to
    # refresh_from_db() or they won't display in the UI correctly

[docs]    __table_args__ = (
        Index('ti_dag_state', dag_id, state),
        Index('ti_dag_run', dag_id, run_id),
        Index('ti_state', state),
        Index('ti_state_lkp', dag_id, task_id, run_id, state),
        Index('ti_pool', pool, state, priority_weight),
        Index('ti_job_id', job_id),
        Index('ti_trigger_id', trigger_id),
        ForeignKeyConstraint(
            [trigger_id],
            ['trigger.id'],
            name='task_instance_trigger_id_fkey',
            ondelete='CASCADE',
        ),
        ForeignKeyConstraint(
            [dag_id, run_id],
            ["dag_run.dag_id", "dag_run.run_id"],
            name='task_instance_dag_run_fkey',
            ondelete="CASCADE",
        ),
    )

[docs]    dag_model = relationship(
        "DagModel",
        primaryjoin="TaskInstance.dag_id == DagModel.dag_id",
        foreign_keys=dag_id,
        uselist=False,
        innerjoin=True,
        viewonly=True,
    )

[docs]    trigger = relationship(
        "Trigger",
        primaryjoin="TaskInstance.trigger_id == Trigger.id",
        foreign_keys=trigger_id,
        uselist=False,
        innerjoin=True,
    )

[docs]    dag_run = relationship("DagRun", back_populates="task_instances", lazy='joined', innerjoin=True)

[docs]    execution_date = association_proxy("dag_run", "execution_date")

    def __init__(
        self, task, execution_date: Optional[datetime] = None, run_id: str = None, state: Optional[str] = None
    ):
        super().__init__()
        self.dag_id = task.dag_id
        self.task_id = task.task_id
        self.refresh_from_task(task)
        self._log = logging.getLogger("airflow.task")

        if run_id is None and execution_date is not None:
            from airflow.models.dagrun import DagRun  # Avoid circular import

            warnings.warn(
                "Passing an execution_date to `TaskInstance()` is deprecated in favour of passing a run_id",
                DeprecationWarning,
                # Stack level is 4 because SQLA adds some wrappers around the constructor
                stacklevel=4,
            )
            # make sure we have a localized execution_date stored in UTC
            if execution_date and not timezone.is_localized(execution_date):
                self.log.warning(
                    "execution date %s has no timezone information. Using default from dag or system",
                    execution_date,
                )
                if self.task.has_dag():
                    execution_date = timezone.make_aware(execution_date, self.task.dag.timezone)
                else:
                    execution_date = timezone.make_aware(execution_date)

                execution_date = timezone.convert_to_utc(execution_date)
            with create_session() as session:
                run_id = (
                    session.query(DagRun.run_id)
                    .filter_by(dag_id=self.dag_id, execution_date=execution_date)
                    .scalar()
                )
                if run_id is None:
                    raise DagRunNotFound(
                        f"DagRun for {self.dag_id!r} with date {execution_date} not found"
                    ) from None

        self.run_id = run_id

        self.try_number = 0
        self.unixname = getuser()
        if state:
            self.state = state
        self.hostname = ''
        self.init_on_load()
        # Is this TaskInstance being currently running within `airflow tasks run --raw`.
        # Not persisted to the database so only valid for the current process
        self.raw = False
        # can be changed when calling 'run'
        self.test_mode = False

    @reconstructor
[docs]    def init_on_load(self):
        """Initialize the attributes that aren't stored in the DB"""
        self.test_mode = False  # can be changed when calling 'run'

    @property
[docs]    def try_number(self):
        """
        Return the try number that this task number will be when it is actually
        run.

        If the TaskInstance is currently running, this will match the column in the
        database, in all other cases this will be incremented.
        """
        # This is designed so that task logs end up in the right file.
        # TODO: whether we need sensing here or not (in sensor and task_instance state machine)
        if self.state in State.running:
            return self._try_number
        return self._try_number + 1

    @try_number.setter
    def try_number(self, value):
        self._try_number = value

    @property
[docs]    def prev_attempted_tries(self):
        """
        Based on this instance's try_number, this will calculate
        the number of previously attempted tries, defaulting to 0.
        """
        # Expose this for the Task Tries and Gantt graph views.
        # Using `try_number` throws off the counts for non-running tasks.
        # Also useful in error logging contexts to get
        # the try number for the last try that was attempted.
        # https://issues.apache.org/jira/browse/AIRFLOW-2143

        return self._try_number

    @property
[docs]    def next_try_number(self):
        """Setting Next Try Number"""
        return self._try_number + 1

[docs]    def command_as_list(
        self,
        mark_success=False,
        ignore_all_deps=False,
        ignore_task_deps=False,
        ignore_depends_on_past=False,
        ignore_ti_state=False,
        local=False,
        pickle_id=None,
        raw=False,
        job_id=None,
        pool=None,
        cfg_path=None,
    ):
        """
        Returns a command that can be executed anywhere where airflow is
        installed. This command is part of the message sent to executors by
        the orchestrator.
        """
        dag: Union["DAG", "DagModel"]
        # Use the dag if we have it, else fallback to the ORM dag_model, which might not be loaded
        if hasattr(self, 'task') and hasattr(self.task, 'dag'):
            dag = self.task.dag
        else:
            dag = self.dag_model

        should_pass_filepath = not pickle_id and dag
        path = None
        if should_pass_filepath:
            if dag.is_subdag:
                path = dag.parent_dag.relative_fileloc
            else:
                path = dag.relative_fileloc

            if path:
                if not path.is_absolute():
                    path = 'DAGS_FOLDER' / path
                path = str(path)

        return TaskInstance.generate_command(
            self.dag_id,
            self.task_id,
            run_id=self.run_id,
            mark_success=mark_success,
            ignore_all_deps=ignore_all_deps,
            ignore_task_deps=ignore_task_deps,
            ignore_depends_on_past=ignore_depends_on_past,
            ignore_ti_state=ignore_ti_state,
            local=local,
            pickle_id=pickle_id,
            file_path=path,
            raw=raw,
            job_id=job_id,
            pool=pool,
            cfg_path=cfg_path,
        )

    @staticmethod
[docs]    def generate_command(
        dag_id: str,
        task_id: str,
        run_id: str = None,
        mark_success: bool = False,
        ignore_all_deps: bool = False,
        ignore_depends_on_past: bool = False,
        ignore_task_deps: bool = False,
        ignore_ti_state: bool = False,
        local: bool = False,
        pickle_id: Optional[int] = None,
        file_path: Optional[str] = None,
        raw: bool = False,
        job_id: Optional[str] = None,
        pool: Optional[str] = None,
        cfg_path: Optional[str] = None,
    ) -> List[str]:
        """
        Generates the shell command required to execute this task instance.

        :param dag_id: DAG ID
        :type dag_id: str
        :param task_id: Task ID
        :type task_id: str
        :param run_id: The run_id of this task's DagRun
        :type run_id: datetime
        :param mark_success: Whether to mark the task as successful
        :type mark_success: bool
        :param ignore_all_deps: Ignore all ignorable dependencies.
            Overrides the other ignore_* parameters.
        :type ignore_all_deps: bool
        :param ignore_depends_on_past: Ignore depends_on_past parameter of DAGs
            (e.g. for Backfills)
        :type ignore_depends_on_past: bool
        :param ignore_task_deps: Ignore task-specific dependencies such as depends_on_past
            and trigger rule
        :type ignore_task_deps: bool
        :param ignore_ti_state: Ignore the task instance's previous failure/success
        :type ignore_ti_state: bool
        :param local: Whether to run the task locally
        :type local: bool
        :param pickle_id: If the DAG was serialized to the DB, the ID
            associated with the pickled DAG
        :type pickle_id: Optional[int]
        :param file_path: path to the file containing the DAG definition
        :type file_path: Optional[str]
        :param raw: raw mode (needs more details)
        :type raw: Optional[bool]
        :param job_id: job ID (needs more details)
        :type job_id: Optional[int]
        :param pool: the Airflow pool that the task should run in
        :type pool: Optional[str]
        :param cfg_path: the Path to the configuration file
        :type cfg_path: Optional[str]
        :return: shell command that can be used to run the task instance
        :rtype: list[str]
        """
        cmd = ["airflow", "tasks", "run", dag_id, task_id, run_id]
        if mark_success:
            cmd.extend(["--mark-success"])
        if pickle_id:
            cmd.extend(["--pickle", str(pickle_id)])
        if job_id:
            cmd.extend(["--job-id", str(job_id)])
        if ignore_all_deps:
            cmd.extend(["--ignore-all-dependencies"])
        if ignore_task_deps:
            cmd.extend(["--ignore-dependencies"])
        if ignore_depends_on_past:
            cmd.extend(["--ignore-depends-on-past"])
        if ignore_ti_state:
            cmd.extend(["--force"])
        if local:
            cmd.extend(["--local"])
        if pool:
            cmd.extend(["--pool", pool])
        if raw:
            cmd.extend(["--raw"])
        if file_path:
            cmd.extend(["--subdir", file_path])
        if cfg_path:
            cmd.extend(["--cfg-path", cfg_path])
        return cmd

    @property
[docs]    def log_url(self):
        """Log URL for TaskInstance"""
        iso = quote(self.execution_date.isoformat())
        base_url = conf.get('webserver', 'BASE_URL')
        return base_url + f"/log?execution_date={iso}&task_id={self.task_id}&dag_id={self.dag_id}"

    @property
[docs]    def mark_success_url(self):
        """URL to mark TI success"""
        iso = quote(self.execution_date.isoformat())
        base_url = conf.get('webserver', 'BASE_URL')
        return base_url + (
            "/confirm"
            f"?task_id={self.task_id}"
            f"&dag_id={self.dag_id}"
            f"&execution_date={iso}"
            "&upstream=false"
            "&downstream=false"
            "&state=success"
        )

    @provide_session
[docs]    def current_state(self, session=None) -> str:
        """
        Get the very latest state from the database, if a session is passed,
        we use and looking up the state becomes part of the session, otherwise
        a new session is used.

        :param session: SQLAlchemy ORM Session
        :type session: Session
        """
        ti = (
            session.query(TaskInstance)
            .filter(
                TaskInstance.dag_id == self.dag_id,
                TaskInstance.task_id == self.task_id,
                TaskInstance.run_id == self.run_id,
            )
            .all()
        )
        if ti:
            state = ti[0].state
        else:
            state = None
        return state

    @provide_session
[docs]    def error(self, session=None):
        """
        Forces the task instance's state to FAILED in the database.

        :param session: SQLAlchemy ORM Session
        :type session: Session
        """
        self.log.error("Recording the task instance as FAILED")
        self.state = State.FAILED
        session.merge(self)
        session.commit()

    @provide_session
[docs]    def refresh_from_db(self, session=None, lock_for_update=False) -> None:
        """
        Refreshes the task instance from the database based on the primary key

        :param session: SQLAlchemy ORM Session
        :type session: Session
        :param lock_for_update: if True, indicates that the database should
            lock the TaskInstance (issuing a FOR UPDATE clause) until the
            session is committed.
        :type lock_for_update: bool
        """
        self.log.debug("Refreshing TaskInstance %s from DB", self)

        qry = session.query(TaskInstance).filter(
            TaskInstance.dag_id == self.dag_id,
            TaskInstance.task_id == self.task_id,
            TaskInstance.run_id == self.run_id,
        )

        if lock_for_update:
            ti: Optional[TaskInstance] = qry.with_for_update().first()
        else:
            ti = qry.first()
        if ti:
            # Fields ordered per model definition
            self.start_date = ti.start_date
            self.end_date = ti.end_date
            self.duration = ti.duration
            self.state = ti.state
            # Get the raw value of try_number column, don't read through the
            # accessor here otherwise it will be incremented by one already.
            self.try_number = ti._try_number
            self.max_tries = ti.max_tries
            self.hostname = ti.hostname
            self.unixname = ti.unixname
            self.job_id = ti.job_id
            self.pool = ti.pool
            self.pool_slots = ti.pool_slots or 1
            self.queue = ti.queue
            self.priority_weight = ti.priority_weight
            self.operator = ti.operator
            self.queued_dttm = ti.queued_dttm
            self.queued_by_job_id = ti.queued_by_job_id
            self.pid = ti.pid
            self.executor_config = ti.executor_config
            self.external_executor_id = ti.external_executor_id
            self.trigger_id = ti.trigger_id
            self.next_method = ti.next_method
            self.next_kwargs = ti.next_kwargs
        else:
            self.state = None

        self.log.debug("Refreshed TaskInstance %s", self)

[docs]    def refresh_from_task(self, task, pool_override=None):
        """
        Copy common attributes from the given task.

        :param task: The task object to copy from
        :type task: airflow.models.BaseOperator
        :param pool_override: Use the pool_override instead of task's pool
        :type pool_override: str
        """
        self.task = task
        self.queue = task.queue
        self.pool = pool_override or task.pool
        self.pool_slots = task.pool_slots
        self.priority_weight = task.priority_weight_total
        self.run_as_user = task.run_as_user
        self.max_tries = task.retries
        self.executor_config = task.executor_config
        self.operator = task.task_type

    @provide_session
[docs]    def clear_xcom_data(self, session=None):
        """
        Clears all XCom data from the database for the task instance

        :param session: SQLAlchemy ORM Session
        :type session: Session
        """
        self.log.debug("Clearing XCom data")
        XCom.clear(
            dag_id=self.dag_id,
            task_id=self.task_id,
            execution_date=self.execution_date,
            session=session,
        )
        self.log.debug("XCom data cleared")

    @property
[docs]    def key(self) -> TaskInstanceKey:
        """Returns a tuple that identifies the task instance uniquely"""
        return TaskInstanceKey(self.dag_id, self.task_id, self.run_id, self.try_number)

    @provide_session
[docs]    def set_state(self, state: str, session=None):
        """
        Set TaskInstance state.

        :param state: State to set for the TI
        :type state: str
        :param session: SQLAlchemy ORM Session
        :type session: Session
        """
        current_time = timezone.utcnow()
        self.log.debug("Setting task state for %s to %s", self, state)
        self.state = state
        self.start_date = self.start_date or current_time
        if self.state in State.finished or self.state == State.UP_FOR_RETRY:
            self.end_date = self.end_date or current_time
            self.duration = (self.end_date - self.start_date).total_seconds()
        session.merge(self)

    @property
[docs]    def is_premature(self):
        """
        Returns whether a task is in UP_FOR_RETRY state and its retry interval
        has elapsed.
        """
        # is the task still in the retry waiting period?
        return self.state == State.UP_FOR_RETRY and not self.ready_for_retry()

    @provide_session
[docs]    def are_dependents_done(self, session=None):
        """
        Checks whether the immediate dependents of this task instance have succeeded or have been skipped.
        This is meant to be used by wait_for_downstream.

        This is useful when you do not want to start processing the next
        schedule of a task until the dependents are done. For instance,
        if the task DROPs and recreates a table.

        :param session: SQLAlchemy ORM Session
        :type session: Session
        """
        task = self.task

        if not task.downstream_task_ids:
            return True

        ti = session.query(func.count(TaskInstance.task_id)).filter(
            TaskInstance.dag_id == self.dag_id,
            TaskInstance.task_id.in_(task.downstream_task_ids),
            TaskInstance.run_id == self.run_id,
            TaskInstance.state.in_([State.SKIPPED, State.SUCCESS]),
        )
        count = ti[0][0]
        return count == len(task.downstream_task_ids)

    @provide_session
[docs]    def get_previous_dagrun(
        self,
        state: Optional[str] = None,
        session: Optional[Session] = None,
    ) -> Optional["DagRun"]:
        """The DagRun that ran before this task instance's DagRun.

        :param state: If passed, it only take into account instances of a specific state.
        :param session: SQLAlchemy ORM Session.
        """
        dag = self.task.dag
        if dag is None:
            return None

        dr = self.get_dagrun(session=session)

        # LEGACY: most likely running from unit tests
        if not dr:
            # Means that this TaskInstance is NOT being run from a DR, but from a catchup
            try:
                # XXX: This uses DAG internals, but as the outer comment
                # said, the block is only reached for legacy reasons for
                # development code, so that's OK-ish.
                schedule = dag.timetable._schedule
            except AttributeError:
                return None
            dt = pendulum.instance(self.execution_date)
            return TaskInstance(
                task=self.task,
                execution_date=schedule.get_prev(dt),
            )

        dr.dag = dag

        # We always ignore schedule in dagrun lookup when `state` is given
        # or the DAG is never scheduled. For legacy reasons, when
        # `catchup=True`, we use `get_previous_scheduled_dagrun` unless
        # `ignore_schedule` is `True`.
        ignore_schedule = state is not None or not dag.timetable.can_run
        if dag.catchup is True and not ignore_schedule:
            last_dagrun = dr.get_previous_scheduled_dagrun(session=session)
        else:
            last_dagrun = dr.get_previous_dagrun(session=session, state=state)

        if last_dagrun:
            return last_dagrun

        return None

    @provide_session
[docs]    def get_previous_ti(
        self, state: Optional[str] = None, session: Session = None
    ) -> Optional['TaskInstance']:
        """
        The task instance for the task that ran before this task instance.

        :param state: If passed, it only take into account instances of a specific state.
        :param session: SQLAlchemy ORM Session
        """
        dagrun = self.get_previous_dagrun(state, session=session)
        if dagrun is None:
            return None
        return dagrun.get_task_instance(self.task_id, session=session)

    @property
[docs]    def previous_ti(self):
        """
        This attribute is deprecated.
        Please use `airflow.models.taskinstance.TaskInstance.get_previous_ti` method.
        """
        warnings.warn(
            """
            This attribute is deprecated.
            Please use `airflow.models.taskinstance.TaskInstance.get_previous_ti` method.
            """,
            DeprecationWarning,
            stacklevel=2,
        )
        return self.get_previous_ti()

    @property
[docs]    def previous_ti_success(self) -> Optional['TaskInstance']:
        """
        This attribute is deprecated.
        Please use `airflow.models.taskinstance.TaskInstance.get_previous_ti` method.
        """
        warnings.warn(
            """
            This attribute is deprecated.
            Please use `airflow.models.taskinstance.TaskInstance.get_previous_ti` method.
            """,
            DeprecationWarning,
            stacklevel=2,
        )
        return self.get_previous_ti(state=State.SUCCESS)

    @provide_session
[docs]    def get_previous_execution_date(
        self,
        state: Optional[str] = None,
        session: Session = None,
    ) -> Optional[pendulum.DateTime]:
        """
        The execution date from property previous_ti_success.

        :param state: If passed, it only take into account instances of a specific state.
        :param session: SQLAlchemy ORM Session
        """
        self.log.debug("previous_execution_date was called")
        prev_ti = self.get_previous_ti(state=state, session=session)
        return prev_ti and pendulum.instance(prev_ti.execution_date)

    @provide_session
[docs]    def get_previous_start_date(
        self, state: Optional[str] = None, session: Session = None
    ) -> Optional[pendulum.DateTime]:
        """
        The start date from property previous_ti_success.

        :param state: If passed, it only take into account instances of a specific state.
        :param session: SQLAlchemy ORM Session
        """
        self.log.debug("previous_start_date was called")
        prev_ti = self.get_previous_ti(state=state, session=session)
        # prev_ti may not exist and prev_ti.start_date may be None.
        return prev_ti and prev_ti.start_date and pendulum.instance(prev_ti.start_date)

    @property
[docs]    def previous_start_date_success(self) -> Optional[pendulum.DateTime]:
        """
        This attribute is deprecated.
        Please use `airflow.models.taskinstance.TaskInstance.get_previous_start_date` method.
        """
        warnings.warn(
            """
            This attribute is deprecated.
            Please use `airflow.models.taskinstance.TaskInstance.get_previous_start_date` method.
            """,
            DeprecationWarning,
            stacklevel=2,
        )
        return self.get_previous_start_date(state=State.SUCCESS)

    @provide_session
[docs]    def are_dependencies_met(self, dep_context=None, session=None, verbose=False):
        """
        Returns whether or not all the conditions are met for this task instance to be run
        given the context for the dependencies (e.g. a task instance being force run from
        the UI will ignore some dependencies).

        :param dep_context: The execution context that determines the dependencies that
            should be evaluated.
        :type dep_context: DepContext
        :param session: database session
        :type session: sqlalchemy.orm.session.Session
        :param verbose: whether log details on failed dependencies on
            info or debug log level
        :type verbose: bool
        """
        dep_context = dep_context or DepContext()
        failed = False
        verbose_aware_logger = self.log.info if verbose else self.log.debug
        for dep_status in self.get_failed_dep_statuses(dep_context=dep_context, session=session):
            failed = True

            verbose_aware_logger(
                "Dependencies not met for %s, dependency '%s' FAILED: %s",
                self,
                dep_status.dep_name,
                dep_status.reason,
            )

        if failed:
            return False

        verbose_aware_logger("Dependencies all met for %s", self)
        return True

    @provide_session
[docs]    def get_failed_dep_statuses(self, dep_context=None, session=None):
        """Get failed Dependencies"""
        dep_context = dep_context or DepContext()
        for dep in dep_context.deps | self.task.deps:
            for dep_status in dep.get_dep_statuses(self, session, dep_context):

                self.log.debug(
                    "%s dependency '%s' PASSED: %s, %s",
                    self,
                    dep_status.dep_name,
                    dep_status.passed,
                    dep_status.reason,
                )

                if not dep_status.passed:
                    yield dep_status

[docs]    def __repr__(self):
        return f"<TaskInstance: {self.dag_id}.{self.task_id} {self.run_id} [{self.state}]>"

[docs]    def next_retry_datetime(self):
        """
        Get datetime of the next retry if the task instance fails. For exponential
        backoff, retry_delay is used as base and will be converted to seconds.
        """
        delay = self.task.retry_delay
        if self.task.retry_exponential_backoff:
            # If the min_backoff calculation is below 1, it will be converted to 0 via int. Thus,
            # we must round up prior to converting to an int, otherwise a divide by zero error
            # will occur in the modded_hash calculation.
            min_backoff = int(math.ceil(delay.total_seconds() * (2 ** (self.try_number - 2))))

            # In the case when delay.total_seconds() is 0, min_backoff will not be rounded up to 1.
            # To address this, we impose a lower bound of 1 on min_backoff. This effectively makes
            # the ceiling function unnecessary, but the ceiling function was retained to avoid
            # introducing a breaking change.
            if min_backoff < 1:
                min_backoff = 1

            # deterministic per task instance
            ti_hash = int(
                hashlib.sha1(
                    "{}#{}#{}#{}".format(
                        self.dag_id, self.task_id, self.execution_date, self.try_number
                    ).encode('utf-8')
                ).hexdigest(),
                16,
            )
            # between 1 and 1.0 * delay * (2^retry_number)
            modded_hash = min_backoff + ti_hash % min_backoff
            # timedelta has a maximum representable value. The exponentiation
            # here means this value can be exceeded after a certain number
            # of tries (around 50 if the initial delay is 1s, even fewer if
            # the delay is larger). Cap the value here before creating a
            # timedelta object so the operation doesn't fail.
            delay_backoff_in_seconds = min(modded_hash, timedelta.max.total_seconds() - 1)
            delay = timedelta(seconds=delay_backoff_in_seconds)
            if self.task.max_retry_delay:
                delay = min(self.task.max_retry_delay, delay)
        return self.end_date + delay

[docs]    def ready_for_retry(self):
        """
        Checks on whether the task instance is in the right state and timeframe
        to be retried.
        """
        return self.state == State.UP_FOR_RETRY and self.next_retry_datetime() < timezone.utcnow()

    @provide_session
[docs]    def get_dagrun(self, session: Session = None):
        """
        Returns the DagRun for this TaskInstance

        :param session: SQLAlchemy ORM Session
        :return: DagRun
        """
        info = inspect(self)
        if info.attrs.dag_run.loaded_value is not NO_VALUE:
            return self.dag_run

        from airflow.models.dagrun import DagRun  # Avoid circular import

        dr = session.query(DagRun).filter(DagRun.dag_id == self.dag_id, DagRun.run_id == self.run_id).one()

        # Record it in the instance for next time. This means that `self.execution_date` will work correctly
        set_committed_value(self, 'dag_run', dr)

        return dr

    @provide_session
[docs]    def check_and_change_state_before_execution(
        self,
        verbose: bool = True,
        ignore_all_deps: bool = False,
        ignore_depends_on_past: bool = False,
        ignore_task_deps: bool = False,
        ignore_ti_state: bool = False,
        mark_success: bool = False,
        test_mode: bool = False,
        job_id: Optional[str] = None,
        pool: Optional[str] = None,
        external_executor_id: Optional[str] = None,
        session=None,
    ) -> bool:
        """
        Checks dependencies and then sets state to RUNNING if they are met. Returns
        True if and only if state is set to RUNNING, which implies that task should be
        executed, in preparation for _run_raw_task

        :param verbose: whether to turn on more verbose logging
        :type verbose: bool
        :param ignore_all_deps: Ignore all of the non-critical dependencies, just runs
        :type ignore_all_deps: bool
        :param ignore_depends_on_past: Ignore depends_on_past DAG attribute
        :type ignore_depends_on_past: bool
        :param ignore_task_deps: Don't check the dependencies of this TaskInstance's task
        :type ignore_task_deps: bool
        :param ignore_ti_state: Disregards previous task instance state
        :type ignore_ti_state: bool
        :param mark_success: Don't run the task, mark its state as success
        :type mark_success: bool
        :param test_mode: Doesn't record success or failure in the DB
        :type test_mode: bool
        :param job_id: Job (BackfillJob / LocalTaskJob / SchedulerJob) ID
        :type job_id: str
        :param pool: specifies the pool to use to run the task instance
        :type pool: str
        :param external_executor_id: The identifier of the celery executor
        :type external_executor_id: str
        :param session: SQLAlchemy ORM Session
        :type session: Session
        :return: whether the state was changed to running or not
        :rtype: bool
        """
        task = self.task
        self.refresh_from_task(task, pool_override=pool)
        self.test_mode = test_mode
        self.refresh_from_db(session=session, lock_for_update=True)
        self.job_id = job_id
        self.hostname = get_hostname()
        self.pid = None

        if not ignore_all_deps and not ignore_ti_state and self.state == State.SUCCESS:
            Stats.incr('previously_succeeded', 1, 1)

        # TODO: Logging needs cleanup, not clear what is being printed
        hr_line_break = "\n" + ("-" * 80)  # Line break

        if not mark_success:
            # Firstly find non-runnable and non-requeueable tis.
            # Since mark_success is not set, we do nothing.
            non_requeueable_dep_context = DepContext(
                deps=RUNNING_DEPS - REQUEUEABLE_DEPS,
                ignore_all_deps=ignore_all_deps,
                ignore_ti_state=ignore_ti_state,
                ignore_depends_on_past=ignore_depends_on_past,
                ignore_task_deps=ignore_task_deps,
            )
            if not self.are_dependencies_met(
                dep_context=non_requeueable_dep_context, session=session, verbose=True
            ):
                session.commit()
                return False

            # For reporting purposes, we report based on 1-indexed,
            # not 0-indexed lists (i.e. Attempt 1 instead of
            # Attempt 0 for the first attempt).
            # Set the task start date. In case it was re-scheduled use the initial
            # start date that is recorded in task_reschedule table
            self.start_date = timezone.utcnow()
            if self.state == State.UP_FOR_RESCHEDULE:
                task_reschedule: TR = TR.query_for_task_instance(self, session=session).first()
                if task_reschedule:
                    self.start_date = task_reschedule.start_date

            # Secondly we find non-runnable but requeueable tis. We reset its state.
            # This is because we might have hit concurrency limits,
            # e.g. because of backfilling.
            dep_context = DepContext(
                deps=REQUEUEABLE_DEPS,
                ignore_all_deps=ignore_all_deps,
                ignore_depends_on_past=ignore_depends_on_past,
                ignore_task_deps=ignore_task_deps,
                ignore_ti_state=ignore_ti_state,
            )
            if not self.are_dependencies_met(dep_context=dep_context, session=session, verbose=True):
                self.state = State.NONE
                self.log.warning(hr_line_break)
                self.log.warning(
                    "Rescheduling due to concurrency limits reached "
                    "at task runtime. Attempt %s of "
                    "%s. State set to NONE.",
                    self.try_number,
                    self.max_tries + 1,
                )
                self.log.warning(hr_line_break)
                self.queued_dttm = timezone.utcnow()
                session.merge(self)
                session.commit()
                return False

        # print status message
        self.log.info(hr_line_break)
        self.log.info("Starting attempt %s of %s", self.try_number, self.max_tries + 1)
        self.log.info(hr_line_break)
        self._try_number += 1

        if not test_mode:
            session.add(Log(State.RUNNING, self))
        self.state = State.RUNNING
        self.external_executor_id = external_executor_id
        self.end_date = None
        if not test_mode:
            session.merge(self)
        session.commit()

        # Closing all pooled connections to prevent
        # "max number of connections reached"
        settings.engine.dispose()  # type: ignore
        if verbose:
            if mark_success:
                self.log.info("Marking success for %s on %s", self.task, self.execution_date)
            else:
                self.log.info("Executing %s on %s", self.task, self.execution_date)
        return True

    def _date_or_empty(self, attr: str):
        result = getattr(self, attr, None)  # type: datetime
        return result.strftime('%Y%m%dT%H%M%S') if result else ''

    def _log_state(self, lead_msg: str = ''):
        self.log.info(
            '%sMarking task as %s.'
            + ' dag_id=%s, task_id=%s,'
            + ' execution_date=%s, start_date=%s, end_date=%s',
            lead_msg,
            self.state.upper(),
            self.dag_id,
            self.task_id,
            self._date_or_empty('execution_date'),
            self._date_or_empty('start_date'),
            self._date_or_empty('end_date'),
        )

    # Ensure we unset next_method and next_kwargs to ensure that any
    # retries don't re-use them.
[docs]    def clear_next_method_args(self):
        self.log.debug("Clearing next_method and next_kwargs.")

        self.next_method = None
        self.next_kwargs = None

    @provide_session
    @Sentry.enrich_errors
    def _run_raw_task(
        self,
        mark_success: bool = False,
        test_mode: bool = False,
        job_id: Optional[str] = None,
        pool: Optional[str] = None,
        error_file: Optional[str] = None,
        session=None,
    ) -> None:
        """
        Immediately runs the task (without checking or changing db state
        before execution) and then sets the appropriate final state after
        completion and runs any post-execute callbacks. Meant to be called
        only after another function changes the state to running.

        :param mark_success: Don't run the task, mark its state as success
        :type mark_success: bool
        :param test_mode: Doesn't record success or failure in the DB
        :type test_mode: bool
        :param pool: specifies the pool to use to run the task instance
        :type pool: str
        :param session: SQLAlchemy ORM Session
        :type session: Session
        """
        self.test_mode = test_mode
        self.refresh_from_task(self.task, pool_override=pool)
        self.refresh_from_db(session=session)
        self.job_id = job_id
        self.hostname = get_hostname()
        self.pid = os.getpid()
        if not test_mode:
            session.merge(self)
            session.commit()
        actual_start_date = timezone.utcnow()
        Stats.incr(f'ti.start.{self.task.dag_id}.{self.task.task_id}')
        try:
            if not mark_success:
                self.task = self.task.prepare_for_execution()
                context = self.get_template_context(ignore_param_exceptions=False)
                self._execute_task_with_callbacks(context)
            if not test_mode:
                self.refresh_from_db(lock_for_update=True, session=session)
            self.state = State.SUCCESS
        except TaskDeferred as defer:
            # The task has signalled it wants to defer execution based on
            # a trigger.
            self._defer_task(defer=defer, session=session)
            self.log.info(
                'Pausing task as DEFERRED. dag_id=%s, task_id=%s, execution_date=%s, start_date=%s',
                self.dag_id,
                self.task_id,
                self._date_or_empty('execution_date'),
                self._date_or_empty('start_date'),
            )
            if not test_mode:
                session.add(Log(self.state, self))
                session.merge(self)
                session.commit()
            return
        except AirflowSmartSensorException as e:
            self.log.info(e)
            return
        except AirflowSkipException as e:
            # Recording SKIP
            # log only if exception has any arguments to prevent log flooding
            if e.args:
                self.log.info(e)
            if not test_mode:
                self.refresh_from_db(lock_for_update=True, session=session)
            self.state = State.SKIPPED
        except AirflowRescheduleException as reschedule_exception:
            self._handle_reschedule(actual_start_date, reschedule_exception, test_mode, session=session)
            session.commit()
            return
        except (AirflowFailException, AirflowSensorTimeout) as e:
            # If AirflowFailException is raised, task should not retry.
            # If a sensor in reschedule mode reaches timeout, task should not retry.
            self.handle_failure(e, test_mode, force_fail=True, error_file=error_file, session=session)
            session.commit()
            raise
        except AirflowException as e:
            if not test_mode:
                self.refresh_from_db(lock_for_update=True, session=session)
            # for case when task is marked as success/failed externally
            # or dagrun timed out and task is marked as skipped
            # current behavior doesn't hit the callbacks
            if self.state in State.finished:
                self.clear_next_method_args()
                session.merge(self)
                session.commit()
                return
            else:
                self.handle_failure(e, test_mode, error_file=error_file, session=session)
                session.commit()
                raise
        except (Exception, KeyboardInterrupt) as e:
            self.handle_failure(e, test_mode, error_file=error_file, session=session)
            session.commit()
            raise
        finally:
            Stats.incr(f'ti.finish.{self.task.dag_id}.{self.task.task_id}.{self.state}')

        # Recording SKIPPED or SUCCESS
        self.clear_next_method_args()
        self.end_date = timezone.utcnow()
        self._log_state()
        self.set_duration()
        if not test_mode:
            session.add(Log(self.state, self))
            session.merge(self)

            session.commit()

    def _execute_task_with_callbacks(self, context):
        """Prepare Task for Execution"""
        from airflow.models.renderedtifields import RenderedTaskInstanceFields

        def signal_handler(signum, frame):
            self.log.error("Received SIGTERM. Terminating subprocesses.")
            self.task.on_kill()
            raise AirflowException("Task received SIGTERM signal")

        signal.signal(signal.SIGTERM, signal_handler)

        # Don't clear Xcom until the task is certain to execute
        self.clear_xcom_data()
        with Stats.timer(f'dag.{self.task.dag_id}.{self.task.task_id}.duration'):

            self.render_templates(context=context)
            RenderedTaskInstanceFields.write(RenderedTaskInstanceFields(ti=self, render_templates=False))
            RenderedTaskInstanceFields.delete_old_records(self.task_id, self.dag_id)

            # Export context to make it available for operators to use.
            airflow_context_vars = context_to_airflow_vars(context, in_env_var_format=True)
            self.log.info(
                "Exporting the following env vars:\n%s",
                '\n'.join(f"{k}={v}" for k, v in airflow_context_vars.items()),
            )

            os.environ.update(airflow_context_vars)

            # Run pre_execute callback
            self.task.pre_execute(context=context)

            # Run on_execute callback
            self._run_execute_callback(context, self.task)

            if self.task.is_smart_sensor_compatible():
                # Try to register it in the smart sensor service.
                registered = False
                try:
                    registered = self.task.register_in_sensor_service(self, context)
                except Exception:
                    self.log.warning(
                        "Failed to register in sensor service."
                        " Continue to run task in non smart sensor mode.",
                        exc_info=True,
                    )

                if registered:
                    # Will raise AirflowSmartSensorException to avoid long running execution.
                    self._update_ti_state_for_sensing()

            # Execute the task
            with set_current_context(context):
                result = self._execute_task(context, self.task)

            # Run post_execute callback
            self.task.post_execute(context=context, result=result)

        Stats.incr(f'operator_successes_{self.task.task_type}', 1, 1)
        Stats.incr('ti_successes')

    @provide_session
    def _update_ti_state_for_sensing(self, session=None):
        self.log.info('Submitting %s to sensor service', self)
        self.state = State.SENSING
        self.start_date = timezone.utcnow()
        session.merge(self)
        session.commit()
        # Raise exception for sensing state
        raise AirflowSmartSensorException("Task successfully registered in smart sensor.")

    def _execute_task(self, context, task_copy):
        """Executes Task (optionally with a Timeout) and pushes Xcom results"""
        # If the task has been deferred and is being executed due to a trigger,
        # then we need to pick the right method to come back to, otherwise
        # we go for the default execute
        execute_callable = task_copy.execute
        if self.next_method:
            # __fail__ is a special signal value for next_method that indicates
            # this task was scheduled specifically to fail.
            if self.next_method == "__fail__":
                next_kwargs = self.next_kwargs or {}
                raise TaskDeferralError(next_kwargs.get("error", "Unknown"))
            # Grab the callable off the Operator/Task and add in any kwargs
            execute_callable = getattr(task_copy, self.next_method)
            if self.next_kwargs:
                execute_callable = partial(execute_callable, **self.next_kwargs)
        # If a timeout is specified for the task, make it fail
        # if it goes beyond
        if task_copy.execution_timeout:
            # If we are coming in with a next_method (i.e. from a deferral),
            # calculate the timeout from our start_date.
            if self.next_method:
                timeout_seconds = (
                    task_copy.execution_timeout - (timezone.utcnow() - self.start_date)
                ).total_seconds()
            else:
                timeout_seconds = task_copy.execution_timeout.total_seconds()
            try:
                # It's possible we're already timed out, so fast-fail if true
                if timeout_seconds <= 0:
                    raise AirflowTaskTimeout()
                # Run task in timeout wrapper
                with timeout(timeout_seconds):
                    result = execute_callable(context=context)
            except AirflowTaskTimeout:
                task_copy.on_kill()
                raise
        else:
            result = execute_callable(context=context)
        # If the task returns a result, push an XCom containing it
        if task_copy.do_xcom_push and result is not None:
            self.xcom_push(key=XCOM_RETURN_KEY, value=result)
        return result

    @provide_session
    def _defer_task(self, session, defer: TaskDeferred):
        """
        Marks the task as deferred and sets up the trigger that is needed
        to resume it.
        """
        from airflow.models.trigger import Trigger

        # First, make the trigger entry
        trigger_row = Trigger.from_object(defer.trigger)
        session.add(trigger_row)
        session.flush()

        # Then, update ourselves so it matches the deferral request
        self.state = State.DEFERRED
        self.trigger_id = trigger_row.id
        self.next_method = defer.method_name
        self.next_kwargs = defer.kwargs or {}

        # Decrement try number so the next one is the same try
        self._try_number -= 1

        # Calculate timeout too if it was passed
        if defer.timeout is not None:
            self.trigger_timeout = timezone.utcnow() + defer.timeout
        else:
            self.trigger_timeout = None

        # If an execution_timeout is set, set the timeout to the minimum of
        # it and the trigger timeout
        execution_timeout = self.task.execution_timeout
        if execution_timeout:
            if self.trigger_timeout:
                self.trigger_timeout = min(self.start_date + execution_timeout, self.trigger_timeout)
            else:
                self.trigger_timeout = self.start_date + execution_timeout

    def _run_execute_callback(self, context: Context, task):
        """Functions that need to be run before a Task is executed"""
        try:
            if task.on_execute_callback:
                task.on_execute_callback(context)
        except Exception:
            self.log.exception("Failed when executing execute callback")

    def _run_finished_callback(self, error: Optional[Union[str, Exception]] = None) -> None:
        """
        Call callback defined for finished state change.

        NOTE: Only invoke this function from caller of self._run_raw_task or
        self.run
        """
        if self.state == State.FAILED:
            task = self.task
            if task.on_failure_callback is not None:
                context = self.get_template_context()
                context["exception"] = error
                try:
                    task.on_failure_callback(context)
                except Exception:
                    self.log.exception("Error when executing on_failure_callback")
        elif self.state == State.SUCCESS:
            task = self.task
            if task.on_success_callback is not None:
                context = self.get_template_context()
                try:
                    task.on_success_callback(context)
                except Exception:
                    self.log.exception("Error when executing on_success_callback")
        elif self.state == State.UP_FOR_RETRY:
            task = self.task
            if task.on_retry_callback is not None:
                context = self.get_template_context()
                context["exception"] = error
                try:
                    task.on_retry_callback(context)
                except Exception:
                    self.log.exception("Error when executing on_retry_callback")

    @provide_session
[docs]    def run(
        self,
        verbose: bool = True,
        ignore_all_deps: bool = False,
        ignore_depends_on_past: bool = False,
        ignore_task_deps: bool = False,
        ignore_ti_state: bool = False,
        mark_success: bool = False,
        test_mode: bool = False,
        job_id: Optional[str] = None,
        pool: Optional[str] = None,
        session=None,
    ) -> None:
        """Run TaskInstance"""
        res = self.check_and_change_state_before_execution(
            verbose=verbose,
            ignore_all_deps=ignore_all_deps,
            ignore_depends_on_past=ignore_depends_on_past,
            ignore_task_deps=ignore_task_deps,
            ignore_ti_state=ignore_ti_state,
            mark_success=mark_success,
            test_mode=test_mode,
            job_id=job_id,
            pool=pool,
            session=session,
        )
        if not res:
            return

        try:
            error_fd = NamedTemporaryFile(delete=True)
            self._run_raw_task(
                mark_success=mark_success,
                test_mode=test_mode,
                job_id=job_id,
                pool=pool,
                error_file=error_fd.name,
                session=session,
            )
        finally:
            error = None if self.state == State.SUCCESS else load_error_file(error_fd)
            error_fd.close()
            self._run_finished_callback(error=error)

[docs]    def dry_run(self):
        """Only Renders Templates for the TI"""
        task = self.task
        task_copy = task.prepare_for_execution()
        self.task = task_copy

        self.render_templates()
        task_copy.dry_run()

    @provide_session
    def _handle_reschedule(self, actual_start_date, reschedule_exception, test_mode=False, session=None):
        # Don't record reschedule request in test mode
        if test_mode:
            return
        self.refresh_from_db(session)

        self.end_date = timezone.utcnow()
        self.set_duration()

        # Log reschedule request
        session.add(
            TaskReschedule(
                self.task,
                self.run_id,
                self._try_number,
                actual_start_date,
                self.end_date,
                reschedule_exception.reschedule_date,
            )
        )

        # set state
        self.state = State.UP_FOR_RESCHEDULE

        # Decrement try_number so subsequent runs will use the same try number and write
        # to same log file.
        self._try_number -= 1

        self.clear_next_method_args()

        session.merge(self)
        session.commit()
        self.log.info('Rescheduling task, marking task as UP_FOR_RESCHEDULE')

    @provide_session
[docs]    def handle_failure(
        self,
        error: Union[str, Exception],
        test_mode: Optional[bool] = None,
        force_fail: bool = False,
        error_file: Optional[str] = None,
        session=None,
    ) -> None:
        """Handle Failure for the TaskInstance"""
        if test_mode is None:
            test_mode = self.test_mode

        if error:
            if isinstance(error, Exception):
                self.log.error("Task failed with exception", exc_info=error)
            else:
                self.log.error("%s", error)
            # external monitoring process provides pickle file so _run_raw_task
            # can send its runtime errors for access by failure callback
            if error_file:
                set_error_file(error_file, error)
        if not test_mode:
            self.refresh_from_db(session)

        task = self.task
        self.end_date = timezone.utcnow()
        self.set_duration()
        Stats.incr(f'operator_failures_{task.task_type}', 1, 1)
        Stats.incr('ti_failures')
        if not test_mode:
            session.add(Log(State.FAILED, self))

            # Log failure duration
            dag_run = self.get_dagrun(session=session)  # self.dag_run not populated by refresh_from_db
            session.add(TaskFail(task, dag_run.execution_date, self.start_date, self.end_date))

        self.clear_next_method_args()

        # Set state correctly and figure out how to log it and decide whether
        # to email

        # Note, callback invocation needs to be handled by caller of
        # _run_raw_task to avoid race conditions which could lead to duplicate
        # invocations or miss invocation.

        # Since this function is called only when the TaskInstance state is running,
        # try_number contains the current try_number (not the next). We
        # only mark task instance as FAILED if the next task instance
        # try_number exceeds the max_tries ... or if force_fail is truthy

        if force_fail or not self.is_eligible_to_retry():
            self.state = State.FAILED
            email_for_state = task.email_on_failure
        else:
            if self.state == State.QUEUED:
                # We increase the try_number so as to fail the task if it fails to start after sometime
                self._try_number += 1
            self.state = State.UP_FOR_RETRY
            email_for_state = task.email_on_retry

        self._log_state('Immediate failure requested. ' if force_fail else '')
        if email_for_state and task.email:
            try:
                self.email_alert(error)
            except Exception:
                self.log.exception('Failed to send email to: %s', task.email)

        if not test_mode:
            session.merge(self)
            session.flush()

    @provide_session
[docs]    def handle_failure_with_callback(
        self,
        error: Union[str, Exception],
        test_mode: Optional[bool] = None,
        force_fail: bool = False,
        session=None,
    ) -> None:
        self.handle_failure(error=error, test_mode=test_mode, force_fail=force_fail, session=session)
        self._run_finished_callback(error=error)

[docs]    def is_eligible_to_retry(self):
        """Is task instance is eligible for retry"""
        if self.state == State.RESTARTING:
            # If a task is cleared when running, it goes into RESTARTING state and is always
            # eligible for retry
            return True

        return self.task.retries and self.try_number <= self.max_tries

[docs]    def get_template_context(self, session: Session = None, ignore_param_exceptions: bool = True) -> Context:
        """Return TI Context"""
        # Do not use provide_session here -- it expunges everything on exit!
        if not session:
            session = settings.Session()
        task = self.task
        dag: DAG = task.dag
        from airflow import macros

        integrate_macros_plugins()

        dag_run = self.get_dagrun(session)
        data_interval = dag.get_run_data_interval(dag_run)

        params = ParamsDict(suppress_exception=ignore_param_exceptions)

        with contextlib.suppress(AttributeError):
            params.update(dag.params)
        if task.params:
            params.update(task.params)
        if conf.getboolean('core', 'dag_run_conf_overrides_params'):
            self.overwrite_params_with_dag_run_conf(params=params, dag_run=dag_run)

        logical_date = timezone.coerce_datetime(self.execution_date)
        ds = logical_date.strftime('%Y-%m-%d')
        ds_nodash = ds.replace('-', '')
        ts = logical_date.isoformat()
        ts_nodash = logical_date.strftime('%Y%m%dT%H%M%S')
        ts_nodash_with_tz = ts.replace('-', '').replace(':', '')

        # Now validates Params and convert them into a simple dict
        task.params = params.validate()

        @cache  # Prevent multiple database access.
        def _get_previous_dagrun_success() -> Optional["DagRun"]:
            return self.get_previous_dagrun(state=State.SUCCESS, session=session)

        def _get_previous_dagrun_data_interval_success() -> Optional["DataInterval"]:
            dagrun = _get_previous_dagrun_success()
            if dagrun is None:
                return None
            return dag.get_run_data_interval(dagrun)

        def get_prev_data_interval_start_success() -> Optional[pendulum.DateTime]:
            data_interval = _get_previous_dagrun_data_interval_success()
            if data_interval is None:
                return None
            return data_interval.start

        def get_prev_data_interval_end_success() -> Optional[pendulum.DateTime]:
            data_interval = _get_previous_dagrun_data_interval_success()
            if data_interval is None:
                return None
            return data_interval.end

        def get_prev_start_date_success() -> Optional[pendulum.DateTime]:
            dagrun = _get_previous_dagrun_success()
            if dagrun is None:
                return None
            return timezone.coerce_datetime(dagrun.start_date)

        # Custom accessors.
        class VariableAccessor:
            """
            Wrapper around Variable. This way you can get variables in
            templates by using ``{{ var.value.variable_name }}`` or
            ``{{ var.value.get('variable_name', 'fallback') }}``.
            """

            def __init__(self):
                self.var = None

            def __getattr__(
                self,
                item: str,
            ):
                self.var = Variable.get(item)
                return self.var

            def __repr__(self):
                return str(self.var)

            @staticmethod
            def get(
                item: str,
                default_var: Any = Variable._Variable__NO_DEFAULT_SENTINEL,
            ):
                """Get Airflow Variable value"""
                return Variable.get(item, default_var=default_var)

        class VariableJsonAccessor:
            """
            Wrapper around Variable. This way you can get variables in
            templates by using ``{{ var.json.variable_name }}`` or
            ``{{ var.json.get('variable_name', {'fall': 'back'}) }}``.
            """

            def __init__(self):
                self.var = None

            def __getattr__(
                self,
                item: str,
            ):
                self.var = Variable.get(item, deserialize_json=True)
                return self.var

            def __repr__(self):
                return str(self.var)

            @staticmethod
            def get(
                item: str,
                default_var: Any = Variable._Variable__NO_DEFAULT_SENTINEL,
            ):
                """Get Airflow Variable after deserializing JSON value"""
                return Variable.get(item, default_var=default_var, deserialize_json=True)

        class ConnectionAccessor:
            """
            Wrapper around Connection. This way you can get connections in
            templates by using ``{{ conn.conn_id }}`` or
            ``{{ conn.get('conn_id') }}``.
            """

            def __getattr__(
                self,
                item: str,
            ):
                return Connection.get_connection_from_secrets(item)

            @staticmethod
            def get(
                item: str,
                default_conn: Any = None,
            ):
                """Get Airflow Connection value"""
                try:
                    return Connection.get_connection_from_secrets(item)
                except AirflowNotFoundException:
                    return default_conn

        # Create lazy proxies for deprecated stuff.

        def deprecated_proxy(
            func: Callable[[], Any],
            *,
            key: str,
            replacements: Optional[List[str]] = None,
        ) -> lazy_object_proxy.Proxy:
            def deprecated_func():
                message = (
                    f"Accessing {key!r} from the template is deprecated and "
                    f"will be removed in a future version."
                )
                if replacements:
                    display_except_last = ", ".join(repr(r) for r in replacements[:-1])
                    if display_except_last:
                        message += f" Please use {display_except_last} or {replacements[-1]!r} instead."
                    else:
                        message += f" Please use {replacements[-1]!r} instead."
                warnings.warn(message, DeprecationWarning)
                return func()

            return lazy_object_proxy.Proxy(deprecated_func)

        @cache
        def get_yesterday_ds() -> str:
            return (self.execution_date - timedelta(1)).strftime('%Y-%m-%d')

        def get_yesterday_ds_nodash() -> str:
            return get_yesterday_ds().replace('-', '')

        @cache
        def get_tomorrow_ds() -> str:
            return (self.execution_date + timedelta(1)).strftime('%Y-%m-%d')

        def get_tomorrow_ds_nodash() -> str:
            return get_tomorrow_ds().replace('-', '')

        @cache
        def get_next_execution_date() -> Optional[pendulum.DateTime]:
            # For manually triggered dagruns that aren't run on a schedule,
            # next/previous execution dates don't make sense, and should be set
            # to execution date for consistency with how execution_date is set
            # for manually triggered tasks, i.e. triggered_date == execution_date.
            if dag_run.external_trigger:
                next_execution_date = dag_run.execution_date
            else:
                with warnings.catch_warnings():
                    warnings.simplefilter("ignore", DeprecationWarning)
                    next_execution_date = dag.following_schedule(self.execution_date)
            if next_execution_date is None:
                return None
            return timezone.coerce_datetime(next_execution_date)

        def get_next_ds() -> Optional[str]:
            execution_date = get_next_execution_date()
            if execution_date is None:
                return None
            return execution_date.strftime('%Y-%m-%d')

        def get_next_ds_nodash() -> Optional[str]:
            ds = get_next_ds()
            if ds is None:
                return ds
            return ds.replace('-', '')

        @cache
        def get_prev_execution_date():
            if dag_run.external_trigger:
                return timezone.coerce_datetime(self.execution_date)
            with warnings.catch_warnings():
                warnings.simplefilter("ignore", DeprecationWarning)
                return dag.previous_schedule(self.execution_date)

        @cache
        def get_prev_ds() -> Optional[str]:
            execution_date = get_prev_execution_date()
            if execution_date is None:
                return None
            return execution_date.strftime(r'%Y-%m-%d')

        def get_prev_ds_nodash() -> Optional[str]:
            prev_ds = get_prev_ds()
            if prev_ds is None:
                return None
            return prev_ds.replace('-', '')

        return {
            'conf': conf,
            'dag': dag,
            'dag_run': dag_run,
            'data_interval_end': timezone.coerce_datetime(data_interval.end),
            'data_interval_start': timezone.coerce_datetime(data_interval.start),
            'ds': ds,
            'ds_nodash': ds_nodash,
            'execution_date': deprecated_proxy(
                lambda: logical_date,
                key='execution_date',
                replacements=['logical_date', 'data_interval_start'],
            ),
            'inlets': task.inlets,
            'logical_date': logical_date,
            'macros': macros,
            'next_ds': deprecated_proxy(get_next_ds, key="next_ds", replacements=["data_interval_end | ds"]),
            'next_ds_nodash': deprecated_proxy(
                get_next_ds_nodash,
                key="next_ds_nodash",
                replacements=["data_interval_end | ds_nodash"],
            ),
            'next_execution_date': deprecated_proxy(
                get_next_execution_date,
                key='next_execution_date',
                replacements=['data_interval_end'],
            ),
            'outlets': task.outlets,
            'params': task.params,
            'prev_data_interval_start_success': lazy_object_proxy.Proxy(get_prev_data_interval_start_success),
            'prev_data_interval_end_success': lazy_object_proxy.Proxy(get_prev_data_interval_end_success),
            'prev_ds': deprecated_proxy(get_prev_ds, key="prev_ds"),
            'prev_ds_nodash': deprecated_proxy(get_prev_ds_nodash, key="prev_ds_nodash"),
            'prev_execution_date': deprecated_proxy(get_prev_execution_date, key='prev_execution_date'),
            'prev_execution_date_success': deprecated_proxy(
                lambda: self.get_previous_execution_date(state=State.SUCCESS, session=session),
                key='prev_execution_date_success',
                replacements=['prev_data_interval_start_success'],
            ),
            'prev_start_date_success': lazy_object_proxy.Proxy(get_prev_start_date_success),
            'run_id': self.run_id,
            'task': task,
            'task_instance': self,
            'task_instance_key_str': f"{task.dag_id}__{task.task_id}__{ds_nodash}",
            'test_mode': self.test_mode,
            'ti': self,
            'tomorrow_ds': deprecated_proxy(get_tomorrow_ds, key='tomorrow_ds'),
            'tomorrow_ds_nodash': deprecated_proxy(get_tomorrow_ds_nodash, key='tomorrow_ds_nodash'),
            'ts': ts,
            'ts_nodash': ts_nodash,
            'ts_nodash_with_tz': ts_nodash_with_tz,
            'var': {
                'json': VariableJsonAccessor(),
                'value': VariableAccessor(),
            },
            'conn': ConnectionAccessor(),
            'yesterday_ds': deprecated_proxy(get_yesterday_ds, key='yesterday_ds'),
            'yesterday_ds_nodash': deprecated_proxy(get_yesterday_ds_nodash, key='yesterday_ds_nodash'),
        }

    @provide_session
[docs]    def get_rendered_template_fields(self, session=None):
        """Fetch rendered template fields from DB"""
        from airflow.models.renderedtifields import RenderedTaskInstanceFields

        rendered_task_instance_fields = RenderedTaskInstanceFields.get_templated_fields(self, session=session)
        if rendered_task_instance_fields:
            for field_name, rendered_value in rendered_task_instance_fields.items():
                setattr(self.task, field_name, rendered_value)
        else:
            try:
                self.render_templates()
            except (TemplateAssertionError, UndefinedError) as e:
                raise AirflowException(
                    "Webserver does not have access to User-defined Macros or Filters "
                    "when Dag Serialization is enabled. Hence for the task that have not yet "
                    "started running, please use 'airflow tasks render' for debugging the "
                    "rendering of template_fields."
                ) from e

    @provide_session
[docs]    def get_rendered_k8s_spec(self, session=None):
        """Fetch rendered template fields from DB"""
        from airflow.models.renderedtifields import RenderedTaskInstanceFields

        rendered_k8s_spec = RenderedTaskInstanceFields.get_k8s_pod_yaml(self, session=session)
        if not rendered_k8s_spec:
            try:
                rendered_k8s_spec = self.render_k8s_pod_yaml()
            except (TemplateAssertionError, UndefinedError) as e:
                raise AirflowException(f"Unable to render a k8s spec for this taskinstance: {e}") from e
        return rendered_k8s_spec

[docs]    def overwrite_params_with_dag_run_conf(self, params, dag_run):
        """Overwrite Task Params with DagRun.conf"""
        if dag_run and dag_run.conf:
            self.log.debug("Updating task params (%s) with DagRun.conf (%s)", params, dag_run.conf)
            params.update(dag_run.conf)

[docs]    def render_templates(self, context: Optional[Context] = None) -> None:
        """Render templates in the operator fields."""
        if not context:
            context = self.get_template_context()

        self.task.render_template_fields(context)

[docs]    def render_k8s_pod_yaml(self) -> Optional[dict]:
        """Render k8s pod yaml"""
        from airflow.kubernetes.kubernetes_helper_functions import create_pod_id  # Circular import

        kube_config = KubeConfig()
        pod = PodGenerator.construct_pod(
            dag_id=self.dag_id,
            task_id=self.task_id,
            pod_id=create_pod_id(self.dag_id, self.task_id),
            try_number=self.try_number,
            kube_image=kube_config.kube_image,
            date=self.execution_date,
            args=self.command_as_list(),
            pod_override_object=PodGenerator.from_obj(self.executor_config),
            scheduler_job_id="worker-config",
            namespace=kube_config.executor_namespace,
            base_worker_pod=PodGenerator.deserialize_model_file(kube_config.pod_template_file),
        )
        settings.pod_mutation_hook(pod)
        sanitized_pod = ApiClient().sanitize_for_serialization(pod)
        return sanitized_pod

[docs]    def get_email_subject_content(self, exception):
        """Get the email subject content for exceptions."""
        # For a ti from DB (without ti.task), return the default value
        # Reuse it for smart sensor to send default email alert
        use_default = not hasattr(self, 'task')
        exception_html = str(exception).replace('\n', '<br>')

        default_subject = 'Airflow alert: {{ti}}'
        # For reporting purposes, we report based on 1-indexed,
        # not 0-indexed lists (i.e. Try 1 instead of
        # Try 0 for the first attempt).
        default_html_content = (
            'Try {{try_number}} out of {{max_tries + 1}}<br>'
            'Exception:<br>{{exception_html}}<br>'
            'Log: <a href="{{ti.log_url}}">Link</a><br>'
            'Host: {{ti.hostname}}<br>'
            'Mark success: <a href="{{ti.mark_success_url}}">Link</a><br>'
        )

        default_html_content_err = (
            'Try {{try_number}} out of {{max_tries + 1}}<br>'
            'Exception:<br>Failed attempt to attach error logs<br>'
            'Log: <a href="{{ti.log_url}}">Link</a><br>'
            'Host: {{ti.hostname}}<br>'
            'Mark success: <a href="{{ti.mark_success_url}}">Link</a><br>'
        )

        if use_default:
            jinja_context = {'ti': self}
            # This function is called after changing the state
            # from State.RUNNING so need to subtract 1 from self.try_number.
            jinja_context.update(
                dict(
                    exception=exception,
                    exception_html=exception_html,
                    try_number=self.try_number - 1,
                    max_tries=self.max_tries,
                )
            )
            jinja_env = jinja2.Environment(
                loader=jinja2.FileSystemLoader(os.path.dirname(__file__)), autoescape=True
            )
            subject = jinja_env.from_string(default_subject).render(**jinja_context)
            html_content = jinja_env.from_string(default_html_content).render(**jinja_context)
            html_content_err = jinja_env.from_string(default_html_content_err).render(**jinja_context)

        else:
            jinja_context = self.get_template_context()

            jinja_context.update(
                dict(
                    exception=exception,
                    exception_html=exception_html,
                    try_number=self.try_number - 1,
                    max_tries=self.max_tries,
                )
            )

            jinja_env = self.task.get_template_env()

            def render(key, content):
                if conf.has_option('email', key):
                    path = conf.get('email', key)
                    with open(path) as f:
                        content = f.read()
                return jinja_env.from_string(content).render(**jinja_context)

            subject = render('subject_template', default_subject)
            html_content = render('html_content_template', default_html_content)
            html_content_err = render('html_content_template', default_html_content_err)

        return subject, html_content, html_content_err

[docs]    def email_alert(self, exception):
        """Send alert email with exception information."""
        subject, html_content, html_content_err = self.get_email_subject_content(exception)
        try:
            send_email(self.task.email, subject, html_content)
        except Exception:
            send_email(self.task.email, subject, html_content_err)

[docs]    def set_duration(self) -> None:
        """Set TI duration"""
        if self.end_date and self.start_date:
            self.duration = (self.end_date - self.start_date).total_seconds()
        else:
            self.duration = None
        self.log.debug("Task Duration set to %s", self.duration)

    @provide_session
[docs]    def xcom_push(
        self,
        key: str,
        value: Any,
        execution_date: Optional[datetime] = None,
        session: Session = None,
    ) -> None:
        """
        Make an XCom available for tasks to pull.

        :param key: A key for the XCom
        :type key: str
        :param value: A value for the XCom. The value is pickled and stored
            in the database.
        :type value: any picklable object
        :param execution_date: if provided, the XCom will not be visible until
            this date. This can be used, for example, to send a message to a
            task on a future date without it being immediately visible.
        :type execution_date: datetime
        :param session: Sqlalchemy ORM Session
        :type session: Session
        """
        self_execution_date = self.get_dagrun(session).execution_date
        if execution_date and execution_date < self_execution_date:
            raise ValueError(
                'execution_date can not be in the past (current '
                'execution_date is {}; received {})'.format(self_execution_date, execution_date)
            )

        XCom.set(
            key=key,
            value=value,
            task_id=self.task_id,
            dag_id=self.dag_id,
            execution_date=execution_date or self_execution_date,
            session=session,
        )

    @provide_session
[docs]    def xcom_pull(
        self,
        task_ids: Optional[Union[str, Iterable[str]]] = None,
        dag_id: Optional[str] = None,
        key: str = XCOM_RETURN_KEY,
        include_prior_dates: bool = False,
        session: Session = None,
    ) -> Any:
        """
        Pull XComs that optionally meet certain criteria.

        The default value for `key` limits the search to XComs
        that were returned by other tasks (as opposed to those that were pushed
        manually). To remove this filter, pass key=None (or any desired value).

        If a single task_id string is provided, the result is the value of the
        most recent matching XCom from that task_id. If multiple task_ids are
        provided, a tuple of matching values is returned. None is returned
        whenever no matches are found.

        :param key: A key for the XCom. If provided, only XComs with matching
            keys will be returned. The default key is 'return_value', also
            available as a constant XCOM_RETURN_KEY. This key is automatically
            given to XComs returned by tasks (as opposed to being pushed
            manually). To remove the filter, pass key=None.
        :type key: str
        :param task_ids: Only XComs from tasks with matching ids will be
            pulled. Can pass None to remove the filter.
        :type task_ids: str or iterable of strings (representing task_ids)
        :param dag_id: If provided, only pulls XComs from this DAG.
            If None (default), the DAG of the calling task is used.
        :type dag_id: str
        :param include_prior_dates: If False, only XComs from the current
            execution_date are returned. If True, XComs from previous dates
            are returned as well.
        :type include_prior_dates: bool
        :param session: Sqlalchemy ORM Session
        :type session: Session
        """
        if dag_id is None:
            dag_id = self.dag_id

        execution_date = self.get_dagrun(session).execution_date

        query = XCom.get_many(
            execution_date=execution_date,
            key=key,
            dag_ids=dag_id,
            task_ids=task_ids,
            include_prior_dates=include_prior_dates,
            session=session,
        )

        # Since we're only fetching the values field, and not the
        # whole class, the @recreate annotation does not kick in.
        # Therefore we need to deserialize the fields by ourselves.
        if is_container(task_ids):
            vals_kv = {
                result.task_id: XCom.deserialize_value(result)
                for result in query.with_entities(XCom.task_id, XCom.value)
            }

            values_ordered_by_id = [vals_kv.get(task_id) for task_id in task_ids]
            return values_ordered_by_id
        else:
            xcom = query.with_entities(XCom.value).first()
            if xcom:
                return XCom.deserialize_value(xcom)

    @provide_session
[docs]    def get_num_running_task_instances(self, session):
        """Return Number of running TIs from the DB"""
        # .count() is inefficient
        return (
            session.query(func.count())
            .filter(
                TaskInstance.dag_id == self.dag_id,
                TaskInstance.task_id == self.task_id,
                TaskInstance.state == State.RUNNING,
            )
            .scalar()
        )

[docs]    def init_run_context(self, raw=False):
        """Sets the log context."""
        self.raw = raw
        self._set_context(self)

    @staticmethod
[docs]    def filter_for_tis(tis: Iterable[Union["TaskInstance", TaskInstanceKey]]) -> Optional[BooleanClauseList]:
        """Returns SQLAlchemy filter to query selected task instances"""
        # DictKeys type, (what we often pass here from the scheduler) is not directly indexable :(
        # Or it might be a generator, but we need to be able to iterate over it more than once
        tis = list(tis)

        if not tis:
            return None

        first = tis[0]

        dag_id = first.dag_id
        run_id = first.run_id
        first_task_id = first.task_id
        # Common path optimisations: when all TIs are for the same dag_id and run_id, or same dag_id
        # and task_id -- this can be over 150x for huge numbers of TIs (20k+)
        if all(t.dag_id == dag_id and t.run_id == run_id for t in tis):
            return and_(
                TaskInstance.dag_id == dag_id,
                TaskInstance.run_id == run_id,
                TaskInstance.task_id.in_(t.task_id for t in tis),
            )
        if all(t.dag_id == dag_id and t.task_id == first_task_id for t in tis):
            return and_(
                TaskInstance.dag_id == dag_id,
                TaskInstance.run_id.in_(t.run_id for t in tis),
                TaskInstance.task_id == first_task_id,
            )

        if settings.Session.bind.dialect.name == 'mssql':
            return or_(
                and_(
                    TaskInstance.dag_id == ti.dag_id,
                    TaskInstance.task_id == ti.task_id,
                    TaskInstance.run_id == ti.run_id,
                )
                for ti in tis
            )
        else:
            return tuple_(TaskInstance.dag_id, TaskInstance.task_id, TaskInstance.run_id).in_(
                [ti.key.primary for ti in tis]
            )


# State of the task instance.
# Stores string version of the task state.
[docs]TaskInstanceStateType = Tuple[TaskInstanceKey, str]


[docs]class SimpleTaskInstance:
    """
    Simplified Task Instance.

    Used to send data between processes via Queues.
    """

    def __init__(self, ti: TaskInstance):
        self._dag_id: str = ti.dag_id
        self._task_id: str = ti.task_id
        self._run_id: datetime = ti.run_id
        self._start_date: datetime = ti.start_date
        self._end_date: datetime = ti.end_date
        self._try_number: int = ti.try_number
        self._state: str = ti.state
        self._executor_config: Any = ti.executor_config
        self._run_as_user: Optional[str] = None
        if hasattr(ti, 'run_as_user'):
            self._run_as_user = ti.run_as_user
        self._pool: str = ti.pool
        self._priority_weight: Optional[int] = None
        if hasattr(ti, 'priority_weight'):
            self._priority_weight = ti.priority_weight
        self._queue: str = ti.queue
        self._key = ti.key

    @property
[docs]    def dag_id(self) -> str:
        return self._dag_id

    @property
[docs]    def task_id(self) -> str:
        return self._task_id

    @property
[docs]    def run_id(self) -> str:
        return self._run_id

    @property
[docs]    def start_date(self) -> datetime:
        return self._start_date

    @property
[docs]    def end_date(self) -> datetime:
        return self._end_date

    @property
[docs]    def try_number(self) -> int:
        return self._try_number

    @property
[docs]    def state(self) -> str:
        return self._state

    @property
[docs]    def pool(self) -> str:
        return self._pool

    @property
[docs]    def priority_weight(self) -> Optional[int]:
        return self._priority_weight

    @property
[docs]    def queue(self) -> str:
        return self._queue

    @property
[docs]    def key(self) -> TaskInstanceKey:
        return self._key

    @property
[docs]    def executor_config(self):
        return self._executor_config


[docs]STATICA_HACK = True
globals()['kcah_acitats'[::-1].upper()] = False
if STATICA_HACK:  # pragma: no cover
    from airflow.job.base_job import BaseJob

[docs]    TaskInstance.queued_by_job = relationship(BaseJob)