airflow-dags/reference/providers/amazon/aws/sensors/cloud_formation.py

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# to you under the Apache License, Version 2.0 (the
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#   http://www.apache.org/licenses/LICENSE-2.0
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"""This module contains sensors for AWS CloudFormation."""
from typing import Optional

try:
    from functools import cached_property
except ImportError:
    from cached_property import cached_property

from airflow.providers.amazon.aws.hooks.cloud_formation import AWSCloudFormationHook
from airflow.sensors.base import BaseSensorOperator
from airflow.utils.decorators import apply_defaults


class CloudFormationCreateStackSensor(BaseSensorOperator):
    """
    Waits for a stack to be created successfully on AWS CloudFormation.

    :param stack_name: The name of the stack to wait for (templated)
    :type stack_name: str
    :param aws_conn_id: ID of the Airflow connection where credentials and extra configuration are
        stored
    :type aws_conn_id: str
    :param poke_interval: Time in seconds that the job should wait between each try
    :type poke_interval: int
    """

    template_fields = ["stack_name"]
    ui_color = "#C5CAE9"

    @apply_defaults
    def __init__(
        self, *, stack_name, aws_conn_id="aws_default", region_name=None, **kwargs
    ):
        super().__init__(**kwargs)
        self.stack_name = stack_name
        self.aws_conn_id = aws_conn_id
        self.region_name = region_name

    def poke(self, context):
        stack_status = self.hook.get_stack_status(self.stack_name)
        if stack_status == "CREATE_COMPLETE":
            return True
        if stack_status in ("CREATE_IN_PROGRESS", None):
            return False
        raise ValueError(f"Stack {self.stack_name} in bad state: {stack_status}")

    @cached_property
    def hook(self) -> AWSCloudFormationHook:
        """Create and return an AWSCloudFormationHook"""
        return AWSCloudFormationHook(
            aws_conn_id=self.aws_conn_id, region_name=self.region_name
        )


class CloudFormationDeleteStackSensor(BaseSensorOperator):
    """
    Waits for a stack to be deleted successfully on AWS CloudFormation.

    :param stack_name: The name of the stack to wait for (templated)
    :type stack_name: str
    :param aws_conn_id: ID of the Airflow connection where credentials and extra configuration are
        stored
    :type aws_conn_id: str
    :param poke_interval: Time in seconds that the job should wait between each try
    :type poke_interval: int
    """

    template_fields = ["stack_name"]
    ui_color = "#C5CAE9"

    @apply_defaults
    def __init__(
        self,
        *,
        stack_name: str,
        aws_conn_id: str = "aws_default",
        region_name: Optional[str] = None,
        **kwargs,
    ):
        super().__init__(**kwargs)
        self.aws_conn_id = aws_conn_id
        self.region_name = region_name
        self.stack_name = stack_name

    def poke(self, context):
        stack_status = self.hook.get_stack_status(self.stack_name)
        if stack_status in ("DELETE_COMPLETE", None):
            return True
        if stack_status == "DELETE_IN_PROGRESS":
            return False
        raise ValueError(f"Stack {self.stack_name} in bad state: {stack_status}")

    @cached_property
    def hook(self) -> AWSCloudFormationHook:
        """Create and return an AWSCloudFormationHook"""
        return AWSCloudFormationHook(
            aws_conn_id=self.aws_conn_id, region_name=self.region_name
        )