[BUG] Registering actor reminder with empty state results in error while receiving it

[natasky]

Expected Behavior

Following code snippet should result in a functioning actor reminder -

await self.register_reminder(
    "my_reminder,
    state=b"",  # <-- EMPTY STATE
    due_time=timedelta(minutes=1),
    period=timedelta(minutes=1),
)

The issue arises from ActorReminderData - __init__ fails for None state (though typing annotations suggest its valid), yet from_dict explicitly sets state to None if its empty.

Actual Behavior

Reminder is registered and daprd does fire it, but the Python SDK fails with code 500 when receiving it. Sample logs from daprd:

2025-02-15T09:23:39.012571944Z time="2025-02-15T09:23:39.012454243Z" level=error msg="Error invoking reminder on actor MyActor||MyActorID: error from actor service: {\"message\":\"ValueError(\\\"only bytes are allowed for state
: <class 'NoneType'>\\\")\",\"errorCode\":\"UNKNOWN\"}" app_id=my-app instance=my-app-instance scope=dapr
.runtime.actor type=log ver=1.14.4

Steps to Reproduce the Problem

Start app with the actor from snippet.

Release Note

RELEASE NOTE: FIX receiving reminders with empty state.

[dapr-bot]

This issue has been automatically marked as stale because it has not had activity in the last 60 days. It will be closed in the next 7 days unless it is tagged (pinned, good first issue, help wanted or triaged/resolved) or other activity occurs. Thank you for your contributions.

[dapr-bot]

This issue has been automatically closed because it has not had activity in the last 67 days. If this issue is still valid, please ping a maintainer and ask them to label it as pinned, good first issue, help wanted or triaged/resolved. Thank you for your contributions.

[dapr-bot]

This issue has been automatically marked as stale because it has not had activity in the last 60 days. It will be closed in the next 7 days unless it is tagged (pinned, good first issue, help wanted or triaged/resolved) or other activity occurs. Thank you for your contributions.

[dapr-bot]

This issue has been automatically closed because it has not had activity in the last 67 days. If this issue is still valid, please ping a maintainer and ask them to label it as pinned, good first issue, help wanted or triaged/resolved. Thank you for your contributions.