Realm Database Full Sync - How to implement a global comment system

I need to implement a shared global realm where users can write new records and delete their previous ones but not delete other users records.

Example, a comment system.

I made it via object permission using query based sync but I cannot understand how to easily implement it via full-sync.

Has someone done it? How have you accomplished that? Thank you.

You can get that same functionality as long as each user has their own Realm. Permissions on a Full Sync Realm can be offered to other users to allow them read/write access to a users Realm.

See Offering Permissions

You would need to break down your global realm into individual ones but that's one option.

If you are storing all users data on one, global realm. It’s going to be a bit more challenging as you don’t have a fine grained control over what other users are doing.

However, you could implement logic in the app that controls who can/cannot work with an object. So for example, a ToDo object could have a ‘created_by_user_id’ property

class ToDoClass: Object {
   @obc dynamic var to_do_id = ""
   @obc dynamic var created_by_uid = ""

    override static func primaryKey() -> String? {
        return "to_do_id"
    }
}

and using app logic, when another user goes to delete that users ToDo, it could compare the created_by_uid property to the current users id to see if they match. If not, disallow delete.

I was thinking of using a node js server that update a global database when something happens in the users databases.

It works like this (tested, I need to understand how it scales.

I use a listener for users databases, so users can insert rows in their database offline and when they go back online the node js server can replicate the data on the global database). So on the client I’ll have a property with the sync status (local, synched, deleted ) on the classes I need offline.