Source code for airflow.models.taskinstance

# -*- coding: utf-8 -*-
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import copy
import functools
import getpass
import hashlib
import logging
import math
import os
import signal
import time
from datetime import timedelta
from typing import Optional
from urllib.parse import quote

import dill
import lazy_object_proxy
import pendulum
from six.moves.urllib.parse import quote_plus
from sqlalchemy import Column, String, Float, Integer, PickleType, Index, func
from sqlalchemy.orm import reconstructor
from sqlalchemy.orm.session import Session

from airflow import settings
from airflow.configuration import conf
from airflow.exceptions import (
    AirflowException, AirflowTaskTimeout, AirflowSkipException, AirflowRescheduleException
from airflow.models.base import Base, ID_LEN
from airflow.models.log import Log
from airflow.models.pool import Pool
from airflow.models.taskfail import TaskFail
from airflow.models.taskreschedule import TaskReschedule
from airflow.models.variable import Variable
from airflow.models.xcom import XCom, XCOM_RETURN_KEY
from airflow.sentry import Sentry
from airflow.settings import Stats
from airflow.ti_deps.dep_context import DepContext, REQUEUEABLE_DEPS, RUNNING_DEPS
from airflow.utils import timezone
from airflow.utils.db import provide_session
from import send_email
from airflow.utils.helpers import is_container
from airflow.utils.log.logging_mixin import LoggingMixin
from import get_hostname
from airflow.utils.sqlalchemy import UtcDateTime
from airflow.utils.state import State
from airflow.utils.timeout import timeout

[docs]def clear_task_instances(tis, session, activate_dag_runs=True, dag=None, ): """ 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 activate_dag_runs: flag to check for active dag run :param dag: DAG object """ job_ids = [] for ti in tis: if ti.state == State.RUNNING: if ti.job_id: ti.state = State.SHUTDOWN 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) 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# Ignore errors when updating max_tries if dag is None or # task not found in dag since database records could be # outdated.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 current task try number. ti.max_tries = max(ti.max_tries, ti.try_number - 1) ti.state = State.NONE session.merge(ti) # Clear all reschedules related to the ti to clear TR = TaskReschedule session.query(TR).filter( TR.dag_id == ti.dag_id, TR.task_id == ti.task_id, TR.execution_date == ti.execution_date, TR.try_number == ti.try_number ).delete() if job_ids: from import BaseJob as BJ for job in session.query(BJ).filter( job.state = State.SHUTDOWN if activate_dag_runs and tis: from airflow.models.dagrun import DagRun # Avoid circular import drs = session.query(DagRun).filter( DagRun.dag_id.in_({ti.dag_id for ti in tis}), DagRun.execution_date.in_({ti.execution_date for ti in tis}), ).all() for dr in drs: dr.state = State.RUNNING dr.start_date = timezone.utcnow()
[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), primary_key=True)
[docs] dag_id = Column(String(ID_LEN), primary_key=True)
[docs] execution_date = Column(UtcDateTime, primary_key=True)
[docs] start_date = Column(UtcDateTime)
[docs] end_date = Column(UtcDateTime)
[docs] duration = Column(Float)
[docs] state = Column(String(20))
[docs] _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(50), nullable=False)
[docs] queue = Column(String(256))
[docs] priority_weight = Column(Integer)
[docs] operator = Column(String(1000))
[docs] queued_dttm = Column(UtcDateTime)
[docs] pid = Column(Integer)
[docs] executor_config = Column(PickleType(pickler=dill))
[docs] __table_args__ = ( Index('ti_dag_state', dag_id, state), Index('ti_dag_date', dag_id, execution_date), Index('ti_state', state), Index('ti_state_lkp', dag_id, task_id, execution_date, state), Index('ti_pool', pool, state, priority_weight), Index('ti_job_id', job_id),
) def __init__(self, task, execution_date, state=None): self.dag_id = task.dag_id self.task_id = task.task_id self.task = task self._log = logging.getLogger("airflow.task") # 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) self.execution_date = execution_date self.queue = task.queue self.pool = task.pool self.priority_weight = task.priority_weight_total self.try_number = 0 self.max_tries = self.task.retries self.unixname = getpass.getuser() self.run_as_user = task.run_as_user if state: self.state = state self.hostname = '' self.executor_config = task.executor_config self.init_on_load() # Is this TaskInstance being currently running within `airflow run --raw`. # Not persisted to the database so only valid for the current process self.raw = 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'
[docs] def try_number(self): """ Return the try number that this task number will be when it is actually run. If the TI is currently running, this will match the column in the databse, in all othercases this will be incremenetd """ # This is designed so that task logs end up in the right file. if self.state == 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 next_try_number(self): return self._try_number + 1
[docs] def command( self, mark_success=False, ignore_all_deps=False, ignore_depends_on_past=False, ignore_task_deps=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. """ return " ".join(self.command_as_list( mark_success=mark_success, 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, local=local, pickle_id=pickle_id, raw=raw, job_id=job_id, pool=pool, cfg_path=cfg_path))
[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 = self.task.dag should_pass_filepath = not pickle_id and dag if should_pass_filepath and dag.full_filepath != dag.filepath: path = "DAGS_FOLDER/{}".format(dag.filepath) elif should_pass_filepath and dag.full_filepath: path = dag.full_filepath else: path = None return TaskInstance.generate_command( self.dag_id, self.task_id, self.execution_date, 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)
[docs] def generate_command(dag_id, task_id, execution_date, mark_success=False, ignore_all_deps=False, ignore_depends_on_past=False, ignore_task_deps=False, ignore_ti_state=False, local=False, pickle_id=None, file_path=None, raw=False, job_id=None, pool=None, cfg_path=None ): """ Generates the shell command required to execute this task instance. :param dag_id: DAG ID :type dag_id: unicode :param task_id: Task ID :type task_id: unicode :param execution_date: Execution date for the task :type execution_date: datetime.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: unicode :param file_path: path to the file containing the DAG definition :param raw: raw mode (needs more details) :param job_id: job ID (needs more details) :param pool: the Airflow pool that the task should run in :type pool: unicode :param cfg_path: the Path to the configuration file :type cfg_path: basestring :return: shell command that can be used to run the task instance """ iso = execution_date.isoformat() cmd = ["airflow", "run", str(dag_id), str(task_id), str(iso)] cmd.extend(["--mark_success"]) if mark_success else None cmd.extend(["--pickle", str(pickle_id)]) if pickle_id else None cmd.extend(["--job_id", str(job_id)]) if job_id else None cmd.extend(["-A"]) if ignore_all_deps else None cmd.extend(["-i"]) if ignore_task_deps else None cmd.extend(["-I"]) if ignore_depends_on_past else None cmd.extend(["--force"]) if ignore_ti_state else None cmd.extend(["--local"]) if local else None cmd.extend(["--pool", pool]) if pool else None cmd.extend(["--raw"]) if raw else None cmd.extend(["-sd", file_path]) if file_path else None cmd.extend(["--cfg_path", cfg_path]) if cfg_path else None return cmd
[docs] def log_filepath(self): iso = self.execution_date.isoformat() log = os.path.expanduser(conf.get('core', 'BASE_LOG_FOLDER')) return ("{log}/{dag_id}/{task_id}/{iso}.log".format( log=log, dag_id=self.dag_id, task_id=self.task_id, iso=iso))
[docs] def log_url(self): iso = self.execution_date.isoformat() base_url = conf.get('webserver', 'BASE_URL') relative_url = '/log?execution_date={iso}&task_id={task_id}&dag_id={dag_id}'.format( iso=quote_plus(iso), task_id=quote_plus(self.task_id), dag_id=quote_plus(self.dag_id)) if conf.getboolean('webserver', 'rbac'): return '{base_url}{relative_url}'.format(base_url=base_url, relative_url=relative_url) return '{base_url}/admin/airflow{relative_url}'.format(base_url=base_url, relative_url=relative_url)
[docs] def mark_success_url(self): iso = quote(self.execution_date.isoformat()) base_url = conf.get('webserver', 'BASE_URL') return base_url + ( "/success" "?task_id={task_id}" "&dag_id={dag_id}" "&execution_date={iso}" "&upstream=false" "&downstream=false" ).format(task_id=self.task_id, dag_id=self.dag_id, iso=iso)
[docs] def current_state(self, session=None): """ 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. """ TI = TaskInstance ti = session.query(TI).filter( TI.dag_id == self.dag_id, TI.task_id == self.task_id, TI.execution_date == self.execution_date, ).all() if ti: state = ti[0].state else: state = None return state
[docs] def error(self, session=None): """ Forces the task instance's state to FAILED in the database. """ self.log.error("Recording the task instance as FAILED") self.state = State.FAILED session.merge(self) session.commit()
[docs] def refresh_from_db(self, session=None, lock_for_update=False, refresh_executor_config=False): """ Refreshes the task instance from the database based on the primary key :param refresh_executor_config: if True, revert executor config to result from DB. Often, however, we will want to keep the newest version :param lock_for_update: if True, indicates that the database should lock the TaskInstance (issuing a FOR UPDATE clause) until the session is committed. """ TI = TaskInstance qry = session.query(TI).filter( TI.dag_id == self.dag_id, TI.task_id == self.task_id, TI.execution_date == self.execution_date) if lock_for_update: ti = qry.with_for_update().first() else: ti = qry.first() if ti: self.state = ti.state self.start_date = ti.start_date self.end_date = ti.end_date # Get the raw value of try_number column, don't read through the # accessor here otherwise it will be incremeneted by one already. self.try_number = ti._try_number self.max_tries = ti.max_tries self.hostname = ti.hostname = if refresh_executor_config: self.executor_config = ti.executor_config else: self.state = None
[docs] def clear_xcom_data(self, session=None): """ Clears all XCom data from the database for the task instance """ session.query(XCom).filter( XCom.dag_id == self.dag_id, XCom.task_id == self.task_id, XCom.execution_date == self.execution_date ).delete() session.commit()
[docs] def key(self): """ Returns a tuple that identifies the task instance uniquely """ return self.dag_id, self.task_id, self.execution_date, self.try_number
[docs] def set_state(self, state, session=None, commit=True): self.state = state self.start_date = timezone.utcnow() self.end_date = timezone.utcnow() session.merge(self) if commit: session.commit()
[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()
[docs] def are_dependents_done(self, session=None): """ Checks whether the dependents of this task instance have all succeeded. 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. """ 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.execution_date == self.execution_date, TaskInstance.state == State.SUCCESS, ) count = ti[0][0] return count == len(task.downstream_task_ids)
[docs] def _get_previous_ti(self, state=None, session=None): # type: (Optional[str], Session) -> Optional['TaskInstance'] dag = self.task.dag if dag: dr = self.get_dagrun(session=session) # LEGACY: most likely running from unit tests if not dr: # Means that this TI is NOT being run from a DR, but from a catchup previous_scheduled_date = dag.previous_schedule(self.execution_date) if not previous_scheduled_date: return None return TaskInstance(task=self.task, execution_date=previous_scheduled_date) dr.dag = dag # We always ignore schedule in dagrun lookup when `state` is given or `schedule_interval is None`. # For legacy reasons, when `catchup=True`, we use `get_previous_scheduled_dagrun` unless # `ignore_schedule` is `True`. ignore_schedule = state is not None or dag.schedule_interval is None 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.get_task_instance(self.task_id, session=session) return None
[docs] def previous_ti(self): # type: () -> Optional['TaskInstance'] """The task instance for the task that ran before this task instance.""" return self._get_previous_ti()
[docs] def previous_ti_success(self): # type: () -> Optional['TaskInstance'] """The ti from prior succesful dag run for this task, by execution date.""" return self._get_previous_ti(state=State.SUCCESS)
[docs] def previous_execution_date_success(self): # type: () -> Optional[pendulum.datetime] """The execution date from property previous_ti_success.""" self.log.debug("previous_execution_date_success was called") prev_ti = self._get_previous_ti(state=State.SUCCESS) return prev_ti and prev_ti.execution_date
[docs] def previous_start_date_success(self): # type: () -> Optional[pendulum.datetime] """The start date from property previous_ti_success.""" self.log.debug("previous_start_date_success was called") prev_ti = self._get_previous_ti(state=State.SUCCESS) return prev_ti and prev_ti.start_date
[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 = 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
[docs] def get_failed_dep_statuses( self, dep_context=None, session=None): 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 ( "<TaskInstance: {ti.dag_id}.{ti.task_id} " "{ti.execution_date} [{ti.state}]>" ).format(ti=self)
[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 occurr in the modded_hash calculation. min_backoff = int(math.ceil(delay.total_seconds() * (2 ** (self.try_number - 2)))) # deterministic per task instance 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 + 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())
[docs] def pool_full(self, session): """ Returns a boolean as to whether the slot pool has room for this task to run """ if not self.task.pool: return False pool = ( session .query(Pool) .filter(Pool.pool == self.task.pool) .first() ) if not pool: return False open_slots = pool.open_slots(session=session) return open_slots <= 0
[docs] def get_dagrun(self, session): """ Returns the DagRun for this TaskInstance :param session: :return: DagRun """ from airflow.models.dagrun import DagRun # Avoid circular import dr = session.query(DagRun).filter( DagRun.dag_id == self.dag_id, DagRun.execution_date == self.execution_date ).first() return dr
[docs] def _check_and_change_state_before_execution( self, verbose=True, ignore_all_deps=False, ignore_depends_on_past=False, ignore_task_deps=False, ignore_ti_state=False, mark_success=False, test_mode=False, job_id=None, pool=None, session=None): """ 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 TI'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 pool: specifies the pool to use to run the task instance :type pool: str :return: whether the state was changed to running or not :rtype: bool """ task = self.task self.pool = pool or task.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.operator = task.__class__.__name__ 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 = "\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() task_reschedules = TaskReschedule.find_for_task_instance(self, session) if task_reschedules: self.start_date = task_reschedules[0].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) 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) self.queued_dttm = timezone.utcnow() session.merge(self) session.commit() return False # print status message"Starting attempt %s of %s", self.try_number, self.max_tries + 1) self._try_number += 1 if not test_mode: session.add(Log(State.RUNNING, self)) self.state = State.RUNNING = os.getpid() 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() if verbose: if mark_success:"Marking success for %s on %s", self.task, self.execution_date) else:"Executing %s on %s", self.task, self.execution_date) return True
@provide_session @Sentry.enrich_errors
[docs] def _run_raw_task( self, mark_success=False, test_mode=False, job_id=None, pool=None, session=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 """ task = self.task self.pool = pool or task.pool self.test_mode = test_mode self.refresh_from_db(session=session) self.job_id = job_id self.hostname = get_hostname() self.operator = task.__class__.__name__ context = {} actual_start_date = timezone.utcnow() try: if not mark_success: context = self.get_template_context() task_copy = copy.copy(task) self.task = task_copy def signal_handler(signum, frame): self.log.error("Received SIGTERM. Terminating subprocesses.") task_copy.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() start_time = time.time() self.render_templates(context=context) task_copy.pre_execute(context=context) # If a timeout is specified for the task, make it fail # if it goes beyond result = None if task_copy.execution_timeout: try: with timeout(int( task_copy.execution_timeout.total_seconds())): result = task_copy.execute(context=context) except AirflowTaskTimeout: task_copy.on_kill() raise else: result = task_copy.execute(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) task_copy.post_execute(context=context, result=result) end_time = time.time() duration = end_time - start_time Stats.timing( 'dag.{dag_id}.{task_id}.duration'.format( dag_id=task_copy.dag_id, task_id=task_copy.task_id), duration) Stats.incr('operator_successes_{}'.format( self.task.__class__.__name__), 1, 1) Stats.incr('ti_successes') self.refresh_from_db(lock_for_update=True) self.state = State.SUCCESS except AirflowSkipException as e: # log only if exception has any arguments to prevent log flooding if e.args: self.refresh_from_db(lock_for_update=True) self.state = State.SKIPPED except AirflowRescheduleException as reschedule_exception: self.refresh_from_db() self._handle_reschedule(actual_start_date, reschedule_exception, test_mode, context) return except AirflowException as e: self.refresh_from_db() # for case when task is marked as success/failed externally # current behavior doesn't hit the success callback if self.state in {State.SUCCESS, State.FAILED}: return else: self.handle_failure(e, test_mode, context) raise except (Exception, KeyboardInterrupt) as e: self.handle_failure(e, test_mode, context) raise # Success callback try: if task.on_success_callback: task.on_success_callback(context) except Exception as e3: self.log.error("Failed when executing success callback") self.log.exception(e3) # Recording SUCCESS self.end_date = timezone.utcnow() self.set_duration() if not test_mode: session.add(Log(self.state, self)) session.merge(self) session.commit()
[docs] def run( self, verbose=True, ignore_all_deps=False, ignore_depends_on_past=False, ignore_task_deps=False, ignore_ti_state=False, mark_success=False, test_mode=False, job_id=None, pool=None, session=None): 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 res: self._run_raw_task( mark_success=mark_success, test_mode=test_mode, job_id=job_id, pool=pool, session=session)
[docs] def dry_run(self): task = self.task task_copy = copy.copy(task) self.task = task_copy self.render_templates() task_copy.dry_run()
[docs] def _handle_reschedule(self, actual_start_date, reschedule_exception, test_mode=False, context=None, session=None): # Don't record reschedule request in test mode if test_mode: return self.end_date = timezone.utcnow() self.set_duration() # Log reschedule request session.add(TaskReschedule(self.task, self.execution_date, 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 session.merge(self) session.commit()'Rescheduling task, marking task as UP_FOR_RESCHEDULE')
[docs] def handle_failure(self, error, test_mode=False, context=None, session=None): self.log.exception(error) task = self.task self.end_date = timezone.utcnow() self.set_duration() Stats.incr('operator_failures_{}'.format(task.__class__.__name__), 1, 1) Stats.incr('ti_failures') if not test_mode: session.add(Log(State.FAILED, self)) # Log failure duration session.add(TaskFail(task, self.execution_date, self.start_date, self.end_date)) if context is not None: context['exception'] = error # Let's go deeper try: # Since this function is called only when the TI 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. if self.is_eligible_to_retry(): self.state = State.UP_FOR_RETRY'Marking task as UP_FOR_RETRY') if task.email_on_retry and self.email_alert(error) else: self.state = State.FAILED if task.retries:'All retries failed; marking task as FAILED') else:'Marking task as FAILED.') if task.email_on_failure and self.email_alert(error) except Exception as e2: self.log.error('Failed to send email to: %s', self.log.exception(e2) # Handling callbacks pessimistically try: if self.state == State.UP_FOR_RETRY and task.on_retry_callback: task.on_retry_callback(context) if self.state == State.FAILED and task.on_failure_callback: task.on_failure_callback(context) except Exception as e3: self.log.error("Failed at executing callback") self.log.exception(e3) if not test_mode: session.merge(self) session.commit()
[docs] def is_eligible_to_retry(self): """Is task instance is eligible for retry""" return self.task.retries and self.try_number <= self.max_tries
[docs] def get_template_context(self, session=None): task = self.task from airflow import macros tables = None if 'tables' in task.params: tables = task.params['tables'] params = {} run_id = '' dag_run = None if hasattr(task, 'dag'): if task.dag.params: params.update(task.dag.params) from airflow.models.dagrun import DagRun # Avoid circular import dag_run = ( session.query(DagRun) .filter_by( dag_id=task.dag.dag_id, execution_date=self.execution_date) .first() ) run_id = dag_run.run_id if dag_run else None session.expunge_all() session.commit() ds = self.execution_date.strftime('%Y-%m-%d') ts = self.execution_date.isoformat() yesterday_ds = (self.execution_date - timedelta(1)).strftime('%Y-%m-%d') tomorrow_ds = (self.execution_date + timedelta(1)).strftime('%Y-%m-%d') # For manually triggered dagruns that aren't run on a schedule, next/previous # schedule 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 and dag_run.external_trigger: prev_execution_date = self.execution_date next_execution_date = self.execution_date else: prev_execution_date = task.dag.previous_schedule(self.execution_date) next_execution_date = task.dag.following_schedule(self.execution_date) next_ds = None next_ds_nodash = None if next_execution_date: next_ds = next_execution_date.strftime('%Y-%m-%d') next_ds_nodash = next_ds.replace('-', '') next_execution_date = pendulum.instance(next_execution_date) prev_ds = None prev_ds_nodash = None if prev_execution_date: prev_ds = prev_execution_date.strftime('%Y-%m-%d') prev_ds_nodash = prev_ds.replace('-', '') prev_execution_date = pendulum.instance(prev_execution_date) ds_nodash = ds.replace('-', '') ts_nodash = self.execution_date.strftime('%Y%m%dT%H%M%S') ts_nodash_with_tz = ts.replace('-', '').replace(':', '') yesterday_ds_nodash = yesterday_ds.replace('-', '') tomorrow_ds_nodash = tomorrow_ds.replace('-', '') ti_key_str = "{dag_id}__{task_id}__{ds_nodash}".format( dag_id=task.dag_id, task_id=task.task_id, ds_nodash=ds_nodash) 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) class VariableAccessor: """ Wrapper around Variable. This way you can get variables in templates by using {var.value.your_variable_name}. """ def __init__(self): self.var = None def __getattr__(self, item): self.var = Variable.get(item) return self.var def __repr__(self): return str(self.var) class VariableJsonAccessor: """ Wrapper around deserialized Variables. This way you can get variables in templates by using {var.json.your_variable_name}. """ def __init__(self): self.var = None def __getattr__(self, item): self.var = Variable.get(item, deserialize_json=True) return self.var def __repr__(self): return str(self.var) return { 'conf': conf, 'dag': task.dag, 'ds': ds, 'next_ds': next_ds, 'next_ds_nodash': next_ds_nodash, 'prev_ds': prev_ds, 'prev_ds_nodash': prev_ds_nodash, 'ds_nodash': ds_nodash, 'ts': ts, 'ts_nodash': ts_nodash, 'ts_nodash_with_tz': ts_nodash_with_tz, 'yesterday_ds': yesterday_ds, 'yesterday_ds_nodash': yesterday_ds_nodash, 'tomorrow_ds': tomorrow_ds, 'tomorrow_ds_nodash': tomorrow_ds_nodash, 'END_DATE': ds, 'end_date': ds, 'dag_run': dag_run, 'run_id': run_id, 'execution_date': pendulum.instance(self.execution_date), 'prev_execution_date': prev_execution_date, 'prev_execution_date_success': lazy_object_proxy.Proxy( lambda: self.previous_execution_date_success), 'prev_start_date_success': lazy_object_proxy.Proxy(lambda: self.previous_start_date_success), 'next_execution_date': next_execution_date, 'latest_date': ds, 'macros': macros, 'params': params, 'tables': tables, 'task': task, 'task_instance': self, 'ti': self, 'task_instance_key_str': ti_key_str, 'test_mode': self.test_mode, 'var': { 'value': VariableAccessor(), 'json': VariableJsonAccessor() }, 'inlets': task.inlets, 'outlets': task.outlets,
[docs] def overwrite_params_with_dag_run_conf(self, params, dag_run): if dag_run and dag_run.conf: params.update(dag_run.conf)
[docs] def render_templates(self, context=None): """Render templates in the operator fields.""" if not context: context = self.get_template_context() self.task.render_template_fields(context)
[docs] def email_alert(self, exception): exception_html = str(exception).replace('\n', '<br>') jinja_context = self.get_template_context() # 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 = self.task.get_template_env() 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>' 'Log file: {{ti.log_filepath}}<br>' 'Mark success: <a href="{{ti.mark_success_url}}">Link</a><br>' ) def render(key, content): if conf.has_option('email', key): path = conf.get('email', key) with open(path) as f: content = return jinja_env.from_string(content).render(**jinja_context) subject = render('subject_template', default_subject) html_content = render('html_content_template', default_html_content) send_email(, subject, html_content)
[docs] def set_duration(self): if self.end_date and self.start_date: self.duration = (self.end_date - self.start_date).total_seconds() else: self.duration = None
[docs] def xcom_push( self, key, value, execution_date=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 pickleable 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 """ 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)
[docs] def xcom_pull( self, task_ids=None, dag_id=None, key=XCOM_RETURN_KEY, include_prior_dates=False): """ 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 """ if dag_id is None: dag_id = self.dag_id pull_fn = functools.partial( XCom.get_one, execution_date=self.execution_date, key=key, dag_id=dag_id, include_prior_dates=include_prior_dates) if is_container(task_ids): return tuple(pull_fn(task_id=t) for t in task_ids) else: return pull_fn(task_id=task_ids)
[docs] def get_num_running_task_instances(self, session): TI = TaskInstance return session.query(TI).filter( TI.dag_id == self.dag_id, TI.task_id == self.task_id, TI.state == State.RUNNING
[docs] def init_run_context(self, raw=False): """ Sets the log context. """ self.raw = raw self._set_context(self)

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