Source code for airflow.providers.amazon.aws.sensors.step_function_execution
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import json
from typing import Optional
from airflow.exceptions import AirflowException
from airflow.providers.amazon.aws.hooks.step_function import StepFunctionHook
from airflow.sensors.base import BaseSensorOperator
from airflow.utils.decorators import apply_defaults
[docs]class StepFunctionExecutionSensor(BaseSensorOperator):
"""
Asks for the state of the Step Function State Machine Execution until it
reaches a failure state or success state.
If it fails, failing the task.
On successful completion of the Execution the Sensor will do an XCom Push
of the State Machine's output to `output`
:param execution_arn: execution_arn to check the state of
:type execution_arn: str
:param aws_conn_id: aws connection to use, defaults to 'aws_default'
:type aws_conn_id: str
"""
[docs] FAILURE_STATES = (
'FAILED',
'TIMED_OUT',
'ABORTED',
)
[docs] SUCCESS_STATES = ('SUCCEEDED',)
[docs] template_fields = ['execution_arn']
@apply_defaults
def __init__(
self,
*,
execution_arn: str,
aws_conn_id: str = 'aws_default',
region_name: Optional[str] = None,
**kwargs,
):
super().__init__(**kwargs)
self.execution_arn = execution_arn
self.aws_conn_id = aws_conn_id
self.region_name = region_name
self.hook: Optional[StepFunctionHook] = None
[docs] def poke(self, context):
execution_status = self.get_hook().describe_execution(self.execution_arn)
state = execution_status['status']
output = json.loads(execution_status['output']) if 'output' in execution_status else None
if state in self.FAILURE_STATES:
raise AirflowException(f'Step Function sensor failed. State Machine Output: {output}')
if state in self.INTERMEDIATE_STATES:
return False
self.log.info('Doing xcom_push of output')
self.xcom_push(context, 'output', output)
return True
[docs] def get_hook(self) -> StepFunctionHook:
"""Create and return a StepFunctionHook"""
if self.hook:
return self.hook
self.hook = StepFunctionHook(aws_conn_id=self.aws_conn_id, region_name=self.region_name)
return self.hook