I can't figure out how to change a value of Firebase database and then change it back after a certain amount of time(30 min), doing everything on the server side and not by the actual device date.
I'm assuming i need Firebase functions.
In case i can't do it, is there any other way keeping Firebase as main Database?
I don't really need any code but just the logic behind it.
I would question your data model. Instead of using a boolean, you may want to consider using a timestamp.
For example, if your data model is currently something along the lines of:
Permissions
- user_id
- is_allowed (boolean)
You may want to use this instead:
Permissions
- user_id
- allow_until (timestamp)
You application code can then just check if the current time is earlier than the allow_until timestamp.
There is no logic in the Firebase Realtime Database to automatically change a value after a certain amount of time. You'll typically run such code in Cloud Functions, or in the apps in your client devices.
In both cases you can keep using the Firebase Realtime Database, as you'll just be interacting with that. From Cloud Functions you'll do that through the Admin SDK.
It's a few steps:
Create a Cloud Function that queries the database to find expired items, and changes the value on them. This code uses the Admin SDK for Node.js, but is very similar to what you'd otherwise run in a web client.
Tie that Cloud Function to a cron job that runs every minute or so (depending on how accurate you want the time-out to be). For some options, see Cloud Functions for Firebase trigger on time?
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