Impressia/Vernissage/CoreData/CoreDataHandler.swift

78 lines
3.2 KiB
Swift

//
// https://mczachurski.dev
// Copyright © 2022 Marcin Czachurski and the repository contributors.
// Licensed under the MIT License.
//
import CoreData
public class CoreDataHandler {
public static let shared = CoreDataHandler()
public let container: NSPersistentContainer
init(inMemory: Bool = false) {
container = NSPersistentContainer(name: "Vernissage")
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)")
}
})
container.viewContext.automaticallyMergesChangesFromParent = true
}
public func newBackgroundContext() -> NSManagedObjectContext {
self.container.newBackgroundContext()
}
public func save() {
let context = self.container.viewContext
if context.hasChanges {
do {
try context.save()
} catch {
// 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.
let nserror = error as NSError
fatalError("Unresolved error \(nserror), \(nserror.userInfo)")
}
}
}
}
extension CoreDataHandler {
public static var preview: CoreDataHandler = {
let result = CoreDataHandler(inMemory: true)
let viewContext = result.container.viewContext
for _ in 0..<10 {
let newItem = AccountData(context: viewContext)
newItem.id = "123"
}
do {
try viewContext.save()
} catch {
// 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.
let nsError = error as NSError
fatalError("Unresolved error \(nsError), \(nsError.userInfo)")
}
return result
}()
}