AIP-103: Passing AssetStateStoreAccessors through to BaseEventTrigger

[jroachgolf84]

Description

To ensure that classes inheriting from the BaseEventTrigger (typically used for Asset watching) are "Asset-aware", the work done in AIP-103 has been wired into the BaseEventTrigger class.

#65103 drafted an approach that "flipped" the definition of the Asset and AssetWatcher. However, for good reason, the approach was challenged. After conversation, the goal became to "pass" the AssetStateAccessors through to the BaseEventTrigger with some runtime magic.

With this model, defining an Asset and AssetWatcher remains the same as before.

fromairflow.sdkimportAsset, AssetWatcher, DAG, taskfromdatetimeimportdatetimefromtriggers.event_triggersimportGenericEventTriggergeneric_asset_watcher=AssetWatcher(
name="generic_asset_watcher",
trigger=GenericEventTrigger(
random_number=1,
waiter_delay=15
)
)
generic_asset=Asset(
name="generic_asset",
watchers=[generic_asset_watcher],
)
withDAG(
dag_id="aip_93_scoping",
start_date=datetime(2026, 1, 1),
schedule=[generic_asset]
) asdag:
@taskdefdownstream_task():
passdownstream_task()

The two PR's below were closed in favor of this PR:

• aip-93-scoping: Adding AssetWatcher.asset functionality #65103
• AIP-103: Passing Asset name/uri and AssetStateAccessor through to BaseEventTrigger #66595

Testing

No unit tests have been written for this logic yet. However, testing has been performed E2E locally with breeze. The trigger authored below is what was used for testing.

classGenericEventTrigger(BaseEventTrigger):
def__init__(
self,
random_number,
waiter_delay,
asset_name,
**kwargs
):
super().__init__(**kwargs)
self.random_number=random_numberself.waiter_delay=waiter_delayself.asset_name=asset_namedefserialize(self) ->tuple[str, dict[str, Any]]:
"""Serialize the Trigger, including the func, params, and waiter_delay."""return (
self.__class__.__module__+"."+self.__class__.__qualname__,
{
"random_number": self.random_number,
"waiter_delay": self.waiter_delay,
"asset_name": self.asset_name,
},
)
asyncdefrun(self) ->AsyncIterator[TriggerEvent]:
"""Logic that fires a TriggerEvent."""logging.info(f"***** asset_state_store: {self.asset_state_store}")
whileTrue:
result=random.randint(0, 5)
ifresult==self.random_number:
logging.info("yield'ing TriggerEvent")
yieldTriggerEvent({"status": "success", "result": result})
breaklogging.info(f"Sleeping for {self.waiter_delay} seconds")
awaitasyncio.sleep(self.waiter_delay)

Follow Up Work

This PR only injects the accessor, but does not yet wire the get/set logic. In order for the AssetStateStoreAccessor.get()/.set() to be used from within the BaseEventTrigger, additional changes in _handle_request() will need to be made. That will be done in a follow-up PR.

[jroachgolf84]

cc: @cmarteepants

[jroachgolf84]

cc: @vincbeck and @amoghrajesh, I closed the previous PR (#66595) after renaming the branch. We'll use this one instead.

[vincbeck]

One nit but overall I like it

[jroachgolf84]

Unless I get anymore feedback, I'm going to start to write tests for this.

[jroachgolf84]

Going to wait for @amoghrajesh to merge #68438 to make changes.

[amoghrajesh]

Right, i am looking at this one now.

[amoghrajesh]

Thanks for pushing through this, LGTM.

Docs PR will follow?

[github-actions]

uv.lock on main just moved via #68710 ("Add Ray constraints for Python 3.14 in Google provider"), commit 9c49080 and this PR currently conflicts.

Quickest fix:

git fetch upstream main && git rebase upstream/main
rm uv.lock && uv lock
git add uv.lock && git rebase --continue
git push --force-with-lease

Automated nudge — ignore if you're not ready to rebase. This comment is updated in place on future uv.lock bumps.

[jroachgolf84]

@amoghrajesh - good to merge?

[amoghrajesh]

Rebasing this one, to ensure CI stays green.