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airflow.sensors.base

Module Contents

class airflow.sensors.base.BaseSensorOperator(*, poke_interval: float = 60, timeout: float = 60 * 60 * 24 * 7, soft_fail: bool = False, mode: str = 'poke', exponential_backoff: bool = False, **kwargs)[source]

Bases: airflow.models.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 (float) – Time in seconds that the job should wait in between each tries

  • timeout (float) – Time, in seconds before the task times out and fails.

  • mode (str) – How the sensor operates. Options are: { poke | reschedule }, default is poke. When set to poke 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 to reschedule 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

ui_color :str = #e6f1f2[source]
valid_modes :Iterable[str] = ['poke', 'reschedule'][source]
execution_fields = ['poke_interval', 'retries', 'execution_timeout', 'timeout', 'email', 'email_on_retry', 'email_on_failure'][source]
reschedule[source]

Define mode rescheduled sensors.

deps[source]

Adds one additional dependency for all sensor operators that checks if a sensor task instance can be rescheduled.

_validate_input_values(self)[source]
poke(self, context: Dict)[source]

Function that the sensors defined while deriving this class should override.

is_smart_sensor_compatible(self)[source]
register_in_sensor_service(self, ti, context)[source]

Register ti in smart sensor service

Parameters
  • ti – Task instance object.

  • context – TaskInstance template context from the ti.

Returns

boolean

get_poke_context(self, context)[source]

Return a dictionary with all attributes in poke_context_fields. The poke_context with operator class can be used to identify a unique sensor job.

Parameters

context – TaskInstance template context.

Returns

A dictionary with key in poke_context_fields.

get_execution_context(self, context)[source]

Return a dictionary with all attributes in execution_fields. The execution_context include execution requirement for each sensor task such as timeout setup, email_alert setup.

Parameters

context – TaskInstance template context.

Returns

A dictionary with key in execution_fields.

execute(self, context: Dict)[source]
_get_next_poke_interval(self, started_at: Any, run_duration: Callable[], int], try_number)[source]

Using the similar logic which is used for exponential backoff retry delay for operators.

prepare_for_execution(self)[source]
airflow.sensors.base.poke_mode_only(cls)[source]
Class Decorator for child classes of BaseSensorOperator to 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 (type) – BaseSensor class to enforce methods only use ‘poke’ mode.

airflow.sensors.base.apply_defaults[source]

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