I have this Firebase collection structured as shown above, What i'm trying to achieve is to be able to know immediately when the expiration_date has been reached so I can send a notification message to the participant that their session has elapsed...
I have tried using pub/sub trigger that runs every 5 minutes, the problem is that won't scale when the channel IDs get bigger as it has to individually scan through the entire collection and check the expiration_date against the current time.