logActions can get invalid id_member when called from Scheduled tasks

[DiegoAndresCortes]

When triggering removeMembersFromGroups using a scheduled task, it calls logAction > logActions to log the changes.
When using a scheduled task, id_member might be 0, causing the following:

The database value you're trying to insert does not exist: id_member
Function: logActions

Culprit:
https://github.com/SimpleMachines/SMF/blob/release-2.1/Sources/Logging.php#L539-L542

[DiegoAndresCortes]

I can't reproduce it, it's very possible I caused it

[DiegoAndresCortes]

I think I found the issue?
@live627 @sbulen I suppose that $user_info['id'] is 0, when the scheduled task is calling certain functions?

I edited the content of the issue to describe it.
I think a solution could be to replace

else
			$memID = $user_info['id'];

With

else
			$memID = !empty($user_info['id']) ? $user_info['id'] : $log['extra']['member'];

That should always return a valid action (self action if using s scheduled I guess).
And the query below should have ignore to prevent any issues when no users are found.

[DiegoAndresCortes]

I tried to replicate the error but no success.
It's quite strange as even when the error happens, the code execution doesn't stop/doesn't fail, it just throws the error and continues.

[jdarwood007]

I opened #7740 which has more tracing on this. Its because $user_info is null because cron.php does not setup the user data. The missing extra data causes the check to fall back to trying to use the user_info which is null.

[DiegoAndresCortes]

@jdarwood007 Would the initial solution work?

#7546 (comment)