How to enable Core Data Encryption on SwiftUI?

Question

When we are dealing with an UIKit project containing a delegate we just need to add this code

do {
    // Define Options
    let options: [AnyHashable: Any] = [
        NSPersistentStoreFileProtectionKey: FileProtectionType.complete
    ]

    // Add Persistent Store
    try persistentStoreCoordinator.addPersistentStore(ofType: NSSQLiteStoreType,
                                                      configurationName: nil,
                                                      at: persistentStoreURL,
                                                      options: options)
} catch {
    // Error Handling
    ...
}

To have encryption enabled for Core Data.

But how to do that, when you have a SwiftUI app, WITHOUT A DELEGATE that only contains a file called Persistense.swiftcontaining this:

import CoreData

struct PersistenceController {
    static let shared = PersistenceController()

    static var preview: PersistenceController = {
        let result = PersistenceController(inMemory: true)
        let viewContext = result.container.viewContext
      return result
    }()

    let container: NSPersistentContainer

    init(inMemory: Bool = false) {
        container = NSPersistentContainer(name: "TharmaTrack")
        if inMemory {
            container.persistentStoreDescriptions.first!.url = URL(fileURLWithPath: "/dev/null")
        }
        container.loadPersistentStores(completionHandler: { (storeDescription, error) in
            if let error = error as NSError? {
                // Replace this implementation with code to handle the error appropriately.
                // fatalError() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.

                /*
                Typical reasons for an error here include:
                * The parent directory does not exist, cannot be created, or disallows writing.
                * The persistent store is not accessible, due to permissions or data protection when the device is locked.
                * The device is out of space.
                * The store could not be migrated to the current model version.
                Check the error message to determine what the actual problem was.
                */
                fatalError("Unresolved error \(error), \(error.userInfo)")
            }
        })
    }
}

????

Answer 1

The NSPersistentContainer has an array of persistentStoreDescriptions, which you can modify before calling container.loadPersistentStores. In fact, you already do this to change the store’s URL if inMemory is true.

So to set the file protection option:

container = NSPersistentContainer(name: "TharmaTrack")
container.persistentStoreDescriptions.first!.setOption(FileProtectionType.complete as NSObject,
                                                       forKey: NSPersistentStoreFileProtectionKey)