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Automation condition sensors

All automation conditions must be evaluated by a sensor. If you have any assets with an automation condition in your code location, a sensor with the name default_automation_condition_sensor will be created for you automatically. You'll need to toggle this sensor on in the UI for your code location under the Automation tab.

By default, this sensor will evaluate all automation conditions in your code location, and execute the asset or asset check if the condition is met.

Adding additional sensors​

If you have a code location with a large number of assets using automation conditions, you may want to create additional sensors to evaluate only a subset of the conditions. This has a few benefits:

  • Individual evaluations will execute more quickly
  • Operational issues with a single sensor will not impact unrelated assets managed by a different sensor
  • You can toggle automation on and off for targeted sets of assets

To add an additional sensor, create a AutomationConditionSensorDefinition and pass it to the sensors argument of your Definitions object:

import dagster as dg

defs = dg.Definitions(
    sensors=[
        dg.AutomationConditionSensorDefinition(
            "team_b_sensor", target=dg.AssetSelection.groups("team_a")
        ),
        dg.AutomationConditionSensorDefinition(
            "team_a_sensor", target=dg.AssetSelection.groups("team_b")
        ),
    ],
)

When you create new sensors, the default_automation_condition_sensor will only target the automation conditions that are not already covered by the additional sensors.

Default to running​

As with other sensor types, all AutomationConditionSensorDefinitions will default to the STOPPED state when they are first added to a code location. To modify this behavior, create an AutomationConditionSensorDefinition with the default_status argument set to RUNNING:

import dagster as dg

defs = dg.Definitions(
    sensors=[
        dg.AutomationConditionSensorDefinition(
            "run_tags_automation_condition_sensor",
            target=dg.AssetSelection.all(),
            default_status=dg.DefaultSensorStatus.RUNNING,
        )
    ],
)

Adding run tags​

To add tags to runs produced by a given AutomationConditionSensorDefinition, pass a run_tags argument to the AutomationConditionSensorDefinition:

import dagster as dg

defs = dg.Definitions(
    sensors=[
        dg.AutomationConditionSensorDefinition(
            "run_tags_automation_condition_sensor",
            target=dg.AssetSelection.all(),
            run_tags={"key": "value"},
        )
    ],
)