Source code for airflow.providers.apache.livy.sensors.livy

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"""This module contains the Apache Livy sensor."""
from typing import Any, Dict, Optional, Union

from airflow.providers.apache.livy.hooks.livy import LivyHook
from airflow.sensors.base import BaseSensorOperator
from airflow.utils.decorators import apply_defaults


[docs]class LivySensor(BaseSensorOperator):
    """
    Monitor a Livy sessions for termination.

    :param livy_conn_id: reference to a pre-defined Livy connection
    :type livy_conn_id: str
    :param batch_id: identifier of the monitored batch
    :type batch_id: Union[int, str]
    """

[docs]    template_fields = ('batch_id',)

    @apply_defaults
    def __init__(
        self, *, batch_id: Union[int, str], livy_conn_id: str = 'livy_default', **kwargs: Any
    ) -> None:
        super().__init__(**kwargs)
        self._livy_conn_id = livy_conn_id
        self._batch_id = batch_id
        self._livy_hook: Optional[LivyHook] = None

[docs]    def get_hook(self) -> LivyHook:
        """
        Get valid hook.

        :return: hook
        :rtype: LivyHook
        """
        if self._livy_hook is None or not isinstance(self._livy_hook, LivyHook):
            self._livy_hook = LivyHook(livy_conn_id=self._livy_conn_id)
        return self._livy_hook

[docs]    def poke(self, context: Dict[Any, Any]) -> bool:
        batch_id = self._batch_id

        status = self.get_hook().get_batch_state(batch_id)
        return status in self.get_hook().TERMINAL_STATES