airflow.sensors.base
¶
Module Contents¶
Classes¶
Optional return value for poke methods. |
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Sensor operators are derived from this class and inherit these attributes. |
Functions¶
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Decorate a subclass of BaseSensorOperator with poke. |
- class airflow.sensors.base.PokeReturnValue(is_done, xcom_value=None)[source]¶
Optional return value for poke methods.
Sensors can optionally return an instance of the PokeReturnValue class in the poke method. If an XCom value is supplied when the sensor is done, then the XCom value will be pushed through the operator return value. :param is_done: Set to true to indicate the sensor can stop poking. :param xcom_value: An optional XCOM value to be returned by the operator.
- class airflow.sensors.base.BaseSensorOperator(*, poke_interval=60, timeout=conf.getfloat('sensors', 'default_timeout'), soft_fail=False, mode='poke', exponential_backoff=False, max_wait=None, silent_fail=False, **kwargs)[source]¶
Bases:
airflow.models.baseoperator.BaseOperator
,airflow.models.skipmixin.SkipMixin
Sensor operators are derived from this class and inherit these attributes.
Sensor operators keep executing at a time interval and succeed when a criteria is met and fail if and when they time out.
- Parameters
soft_fail (bool) – Set to true to mark the task as SKIPPED on failure
poke_interval (datetime.timedelta | float) – Time that the job should wait in between each try. Can be
timedelta
orfloat
seconds.timeout (datetime.timedelta | float) – Time elapsed before the task times out and fails. Can be
timedelta
orfloat
seconds. This should not be confused withexecution_timeout
of theBaseOperator
class.timeout
measures the time elapsed between the first poke and the current time (taking into account any reschedule delay between each poke), whileexecution_timeout
checks the running time of the task (leaving out any reschedule delay). In case that themode
ispoke
(see below), both of them are equivalent (as the sensor is never rescheduled), which is not the case inreschedule
mode.mode (str) – How the sensor operates. Options are:
{ poke | reschedule }
, default ispoke
. When set topoke
the sensor is taking up a worker slot for its whole execution time and sleeps between pokes. Use this mode if the expected runtime of the sensor is short or if a short poke interval is required. Note that the sensor will hold onto a worker slot and a pool slot for the duration of the sensor’s runtime in this mode. When set toreschedule
the sensor task frees the worker slot when the criteria is not yet met and it’s rescheduled at a later time. Use this mode if the time before the criteria is met is expected to be quite long. The poke interval should be more than one minute to prevent too much load on the scheduler.exponential_backoff (bool) – allow progressive longer waits between pokes by using exponential backoff algorithm
max_wait (datetime.timedelta | float | None) – maximum wait interval between pokes, can be
timedelta
orfloat
secondssilent_fail (bool) – If true, and poke method raises an exception different from AirflowSensorTimeout, AirflowTaskTimeout, AirflowSkipException and AirflowFailException, the sensor will log the error and continue its execution. Otherwise, the sensor task fails, and it can be retried based on the provided retries parameter.
- execute(context)[source]¶
Derive when creating an operator.
Context is the same dictionary used as when rendering jinja templates.
Refer to get_template_context for more context.
- resume_execution(next_method, next_kwargs, context)[source]¶
Call this method when a deferred task is resumed.
- airflow.sensors.base.poke_mode_only(cls)[source]¶
Decorate a subclass of BaseSensorOperator with poke.
Indicate that instances of this class are only safe to use poke mode.
Will decorate all methods in the class to assert they did not change the mode from ‘poke’.
- Parameters
cls – BaseSensor class to enforce methods only use ‘poke’ mode.