Local Realm dbs for multiple users - swift

Question

I'm trying to implement a user based realm db. So each time a new users registers, a Realm file is created with his UID (from Firebase), or if exists, accesses that Realm.
To do that i created a singletone for the Realm calls and setting the Realm Configuration.
My issue now is that, every time i switch the users, the realm path changes (i'm printing after users logged in), but the Results reading are the same, as the users didn't change, or the realm did not switch. To be more clear, the queries results are giving same data.
If i open the actual Realms, the data is different.
I'm seeing this behavior in my tableView, just by loading data.
What am i doing wrong?
RealmServices:
import Foundation
import RealmSwift
import Firebase
class RealmServices {
private init() {}
static let shared = RealmServices()
let userID = Auth.auth().currentUser!.uid
var realm = try! Realm(configuration: Realm.Configuration.init(
fileURL: Realm.Configuration().fileURL!.deletingLastPathComponent().appendingPathComponent("\(Auth.auth().currentUser!.uid).realm")))
func create<T:Object> (_ object: T) {
do {
try realm.write {
realm.add(object)
}
} catch {
post(error)
}
}
func update <T: Object>(_ object: T, with dictionary: [String : Any?]) {
do {
try realm.write {
for (key,value) in dictionary {
object.setValue(value, forKey: key)
}
}
} catch {
post (error)
}
}
func delete<T:Object> (_ object: T) {
do {
try realm.write{
realm.delete(object)
}
} catch {
post (error)
}
}
func post (_ error: Error) {
NotificationCenter.default.post(name: NSNotification.Name("RealmError"), object: error)
}
func observeRealmErrors (in vc: UIViewController, completion: #escaping (Error?)-> Void) {
NotificationCenter.default.addObserver(forName: NSNotification.Name("RealmError"), object: nil, queue: nil) { (Notification) in
completion(Notification.object as? Error)
}
}
func stopObservingError (in vc: UIViewController){
NotificationCenter.default.removeObserver(vc, name: NSNotification.Name("RealmError"), object: nil)
}
}

Answer 1

Here's what I think is going on (I could be totally off but let me give it a shot)
Your RealmServices is a singleton and initialized only once. It's not a subclass where each time one is created, it's initialized
So any var's are set up and populated on first run - the realm property is not going to re-initialize each time it's accessed. For example, take this singleton
final class MySingleton {
private init() {}
var someUuid = UUID().uuidString
static let sharedInstance = MySingleton()
}
as you can see, someUuId is a 'randomly' generated uuid. If you access that property twice, it presents the same value, there's nothing to force an update.
print(MySingleton.sharedInstance.someUuid)
print(MySingleton.sharedInstance.someUuid)
results in
EBE131DE-B574-4CE1-8D74-E680D80A577B
EBE131DE-B574-4CE1-8D74-E680D80A577B
So, the solution is to set the users uid property in your question to a different value each time you want it changed. Here's a quick example
final class RealmService {
private init() {}
var uid: String!
var usersRealm: Realm! {
let path = Realm.Configuration().fileURL!.deletingLastPathComponent().appendingPathComponent("\(uid!).realm")
let realm = try! Realm(configuration: Realm.Configuration.init(fileURL: path))
return realm
}
static let sharedInstance = RealmService()
}
and here's how it's called; in this example we write item0 to user0's realm and item1 to user1's realm:
RealmService.sharedInstance.uid = "uid_0"
let user0Realm = RealmService.sharedInstance.usersRealm!
let item0 = ItemClass(name: "item 0")
try! user0Realm.write {
user0Realm.add(item0)
}
RealmService.sharedInstance.uid = "uid_1"
let user1Realm = RealmService.sharedInstance.usersRealm!
let item1 = ItemClass(name: "item 1")
try! user1Realm.write {
user1Realm.add(item1)
}
the result is a realm being created for each user with item0 in user0's realm and item1 being in user1's realm