airflow/sensors/time_delta.py

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from __future__ import annotations

from airflow.sensors.base import BaseSensorOperator
from airflow.triggers.temporal import DateTimeTrigger
from airflow.utils import timezone
from airflow.utils.context import Context


class TimeDeltaSensor(BaseSensorOperator):
    """
    Waits for a timedelta after the run's data interval.

    :param delta: time length to wait after the data interval before succeeding.

    .. seealso::
        For more information on how to use this sensor, take a look at the guide:
        :ref:`howto/operator:TimeDeltaSensor`


    """

    def __init__(self, *, delta, **kwargs):
        super().__init__(**kwargs)
        self.delta = delta

    def poke(self, context: Context):
        target_dttm = context["data_interval_end"]
        target_dttm += self.delta
        self.log.info("Checking if the time (%s) has come", target_dttm)
        return timezone.utcnow() > target_dttm


class TimeDeltaSensorAsync(TimeDeltaSensor):
    """
    A deferrable drop-in replacement for TimeDeltaSensor.

    Will defers itself to avoid taking up a worker slot while it is waiting.

    :param delta: time length to wait after the data interval before succeeding.

    .. seealso::
        For more information on how to use this sensor, take a look at the guide:
        :ref:`howto/operator:TimeDeltaSensorAsync`

    """

    def execute(self, context: Context):
        target_dttm = context["data_interval_end"]
        target_dttm += self.delta
        self.defer(trigger=DateTimeTrigger(moment=target_dttm), method_name="execute_complete")

    def execute_complete(self, context, event=None):
        """Callback for when the trigger fires - returns immediately."""
        return None