Hello,
I have a iOS app I was looking at porting to Mac.
I'm having an issue with both the Mac (Designed for iPad) and Mac Catalyst Destinations. I can't test Mac due to too many build issues.
I'm trying to assign a new NSManagedObject into a NSPersistentStore.
let object = MyObject(context: context)
context.assign(object, to: nsPersistentStore)
This works fine for iOS/iOS Simulator/iPhone/iPad. But on the Mac it's crashing with
FAULT: NSInvalidArgumentException: Can't assign an object to a store that does not contain the object's entity.; {
Thread 1: "Can't assign an object to a store that does not contain the object's entity."
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I am following Apple's instruction to sync SwiftData with CloudKit. While initiating the ModelContainer, right after removing the store from Core Data, the error occurs:
FAULT: NSInternalInconsistencyException: This NSPersistentStoreCoordinator has no persistent stores (unknown). It cannot perform a save operation.; (user info absent)
I've tried removing default.store and its related files/folders before creating the ModelContainer with FileManager but it does not resolve the issue. Isn't it supposed to create a new store when the ModelContainer is initialized? I don't understand why this error occurs. Error disappears when I comment out the #if DEBUG block.
Code:
import CoreData
import SwiftData
import SwiftUI
struct InitView: View {
@Binding var modelContainer: ModelContainer?
@Binding var isReady: Bool
@State private var loadingDots = ""
@State private var timer: Timer?
var body: some View {
VStack(spacing: 16) {
Text("Loading\(loadingDots)")
.font(.title2)
.foregroundColor(.gray)
}
.padding()
.onAppear {
startAnimation()
registerTransformers()
let config = ModelConfiguration()
let newContainer: ModelContainer
do {
#if DEBUG
// Use an autorelease pool to make sure Swift deallocates the persistent
// container before setting up the SwiftData stack.
try autoreleasepool {
let desc = NSPersistentStoreDescription(url: config.url)
let opts = NSPersistentCloudKitContainerOptions(containerIdentifier: "iCloud.my-container-identifier")
desc.cloudKitContainerOptions = opts
// Load the store synchronously so it completes before initializing the
// CloudKit schema.
desc.shouldAddStoreAsynchronously = false
if let mom = NSManagedObjectModel.makeManagedObjectModel(for: [Page.self]) {
let container = NSPersistentCloudKitContainer(name: "Pages", managedObjectModel: mom)
container.persistentStoreDescriptions = [desc]
container.loadPersistentStores { _, err in
if let err {
fatalError(err.localizedDescription)
}
}
// Initialize the CloudKit schema after the store finishes loading.
try container.initializeCloudKitSchema()
// Remove and unload the store from the persistent container.
if let store = container.persistentStoreCoordinator.persistentStores.first {
try container.persistentStoreCoordinator.remove(store)
}
}
// let fileManager = FileManager.default
// let sqliteURL = config.url
// let urls: [URL] = [
// sqliteURL,
// sqliteURL.deletingLastPathComponent().appendingPathComponent("default.store-shm"),
// sqliteURL.deletingLastPathComponent().appendingPathComponent("default.store-wal"),
// sqliteURL.deletingLastPathComponent().appendingPathComponent(".default_SUPPORT"),
// sqliteURL.deletingLastPathComponent().appendingPathComponent("default_ckAssets")
// ]
// for url in urls {
// try? fileManager.removeItem(at: url)
// }
}
#endif
newContainer = try ModelContainer(for: Page.self,
configurations: config) // ERROR!!!
} catch {
fatalError(error.localizedDescription)
}
modelContainer = newContainer
isReady = true
}
.onDisappear {
stopAnimation()
}
}
private func startAnimation() {
timer = Timer.scheduledTimer(
withTimeInterval: 0.5,
repeats: true
) { _ in
updateLoadingDots()
}
}
private func stopAnimation() {
timer?.invalidate()
timer = nil
}
private func updateLoadingDots() {
if loadingDots.count > 2 {
loadingDots = ""
} else {
loadingDots += "."
}
}
}
import CoreData
import SwiftData
import SwiftUI
@main
struct MyApp: App {
@State private var modelContainer: ModelContainer?
@State private var isReady: Bool = false
var body: some Scene {
WindowGroup {
if isReady, let modelContainer = modelContainer {
ContentView()
.modelContainer(modelContainer)
} else {
InitView(modelContainer: $modelContainer, isReady: $isReady)
}
}
}
}
I am working on a software where we want to add the feature to share the whole database with the other user. Database is iCloud combined with coredata. The other user(s) should be able to edit /delete and even create new objects in the share.
I did this with this code witch directly from sample code
let participants = try await ckConainer.fetchParticipants(matching: [lookupInfo], into: selectedStore)
for participant in participants {
participant.permission = .readWrite
participant.role = .privateUser
share.addParticipant(participant)
}
try await ckConainer.persistUpdatedShare(share, in: selectedStore)
the other user gets invited and I can see this in iCloud database that the other user is invited with status invited.
but the other user never gets a mail or something to accept and join the share. How does the other needs to accept the invitation ?
Using SwiftData and this is the simplest example I could boil down:
@Model
final class Item {
var timestamp: Date
var tag: Tag?
init(timestamp: Date) {
self.timestamp = timestamp
}
}
@Model
final class Tag {
var timestamp: Date
init(timestamp: Date) {
self.timestamp = timestamp
}
}
Notice Tag has no reference to Item.
So if I create a bunch of items and set their Tag. Later on I add the ability to delete a Tag. Since I haven't added inverse relationship Item now references a tag that no longer exists so so I get these types of errors:
SwiftData/BackingData.swift:875: Fatal error: This model instance was invalidated because its backing data could no longer be found the store. PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(url: x-coredata://EEC1D410-F87E-4F1F-B82D-8F2153A0B23C/Tag/p1), implementation: SwiftData.PersistentIdentifierImplementation)
I think I understand now that I just need to add the item reference to Tag and SwiftData will nullify all Item references to that tag when a Tag is deleted.
But, the damage is already done. How can I iterate through all Items that referenced a deleted tag and set them to nil or to a placeholder Tag? Or how can I catch that error and fix it when it comes up?
The crash doesn't occur when loading an Item, only when accessing item.tag?.timestamp, in fact, item.tag?.id is still ok and doesn't crash since it doesn't have to load the backing data.
I've tried things like just looping through all items and setting tag to nil, but saving the model context fails because somewhere in there it still tries to validate the old value.
Thanks!
The NSMetadataUbiquitousItemDownloadingStatusKey indicates the status of a ubiquitous (iCloud Drive) file.
A key value of NSMetadataUbiquitousItemDownloadingStatusDownloaded is defined as indicating there is a local version of this file available. The most current version will get downloaded as soon as possible .
However this no longer occurs since iOS 18.4. A ubiquitous file may remain in the NSMetadataUbiquitousItemDownloadingStatusDownloaded state for an indefinite period.
There is a workaround: call [NSFileManager startDownloadingUbiquitousItemAtURL: error:] however this shouldn't be necessary, and introduces delays over the previous behaviour.
Has anyone else seen this behaviour? Is this a permanent change?
FB17662379
I am trying out the new AttributedString binding with SwiftUI’s TextEditor in iOS26. I need to save this to a Core Data database. Core Data has no AttributedString type, so I set the type of the field to “Transformable”, give it a custom class of NSAttributedString, and set the transformer to NSSecureUnarchiveFromData
When I try to save, I first convert the Swift AttributedString to NSAttributedString, and then save the context. Unfortunately I get this error when saving the context, and the save isn't persisted:
CoreData: error: SQLCore dispatchRequest: exception handling request: <NSSQLSaveChangesRequestContext: 0x600003721140> , <shared NSSecureUnarchiveFromData transformer> threw while encoding a value. with userInfo of (null)
Here's the code that tries to save the attributed string:
struct AttributedDetailView: View {
@ObservedObject var item: Item
@State private var notesText = AttributedString()
var body: some View {
VStack {
TextEditor(text: $notesText)
.padding()
.onChange(of: notesText) {
item.attributedString = NSAttributedString(notesText)
}
}
.onAppear {
if let nsattributed = item.attributedString {
notesText = AttributedString(nsattributed)
} else {
notesText = ""
}
}
.task {
item.attributedString = NSAttributedString(notesText)
do {
try item.managedObjectContext?.save()
} catch {
print("core data save error = \(error)")
}
}
}
}
This is the attribute setup in the Core Data model editor:
Is there a workaround for this?
I filed FB17943846 if someone can take a look.
Thanks.
I want to get to a point where I can use a small view with a query for my SwiftData model like this:
@Query
private var currentTrainingCycle: [TrainingCycle]
init(/*currentDate: Date*/) {
_currentTrainingCycle = Query(filter: #Predicate<TrainingCycle> {
$0.numberOfDays > 0
// $0.startDate < currentDate && currentDate < $0.endDate
}, sort: \.startDate)
}
The commented code is where I want to go. In this instance, it'd be created as a lazy var in a viewModel to have it stable (and not constantly re-creating the view). Since it was not working, I thought I could check the same view with a query that does not require any dynamic input. In this case, the numberOfDays never changes after instantiation.
But still, each time the app tries to create this view, the app becomes unresponsive, the CPU usage goes at 196%, memory goes way high and the device heats up quickly.
Am I holding it wrong? How can I have a dynamic predicate on a View in SwiftUI with SwiftData?
My client is using iCloud Mail with his custom domain and he communicated with many govt organizations which seem to all be using Barracuda Email Protection for their spam prevention. I have properly configured his SPF, DKIM & DMARC DNS records however his emails were still being rejected. (Email header below)
I contacted Barracuda support with the email header and they replied saying that the emails were rejected becuase Apple Mail has missing PTR records.
I have sent dozens of emails for testing and looking at all their headers I can see (ms-asmtp-me-k8s.p00.prod.me.com [17.57.154.37]) which does not have a PTR record.
----FULL EMAIL HEADER WITH 3RD PARTY DOMAINS REMOVED-----
<recipient_email_address>: host
d329469a.ess.barracudanetworks.com[209.222.82.255] said: 550 permanent
failure for one or more recipients (recipient_email_address:blocked)
(in reply to end of DATA command)
Reporting-MTA: dns; p00-icloudmta-asmtp-us-west-3a-100-percent-10.p00-icloudmta-asmtp-vip.icloud-mail-production.svc.kube.us-west-3a.k8s.cloud.apple.com
X-Postfix-Queue-ID: 8979C18013F8
X-Postfix-Sender: rfc822; sender_email_address
Arrival-Date: Thu, 20 Mar 2025 12:30:05 +0000 (UTC)
Final-Recipient: rfc822; @******
Original-Recipient: rfc822;recipient_email_address
Action: failed
Status: 5.0.0
Remote-MTA: dns; d329469a.ess.barracudanetworks.com
Diagnostic-Code: smtp; 550 permanent failure for one or more recipients
(recipient_email_address:blocked)
Return-Path: <sender_email_address>
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sender_domain;
s=sig1; bh=CyUt/U7mIHwXB5OQctPjRH/OxLH7GsLR54JjGuRkj9Y=;
h=From:Message-Id:Content-Type:Mime-Version:Subject:Date:To:x-icloud-hme;
b=hwEbggsctiCRlMlEgovBTjB/0sPRCb2k+1wzHRZ2dZNrZdOqvFSNWU+Aki9Bl8nfv
eEOoXz5qWxO2b2rEBl08lmRQ3hCyroayIn4keBRrgkxL1uu4zMTaDUHyau2vVnzC3h
ZmwQtQxiu7QvTS/Sp8jjJ/niOPSzlfhphqMxnQAZi/jmJGcZPadT8K+7+PhRllVnI+
TElJarN1ORQu+CaPGhEs9/F7AIcjJNemnVg1cude7EUuO9va8ou49oFExWTLt7YSMl
s+88hxxGu3GugD3eBnitzVo7s7/O9qkIbDUjk3w04/p/VOJ+35Mvi+v/zB9brpYwC1
B4dZP+AhwJDYA==
Received: from smtpclient.apple (ms-asmtp-me-k8s.p00.prod.me.com [17.57.154.37])
by p00-icloudmta-asmtp-us-west-3a-100-percent-10.p00-icloudmta-asmtp-vip.icloud-mail-production.svc.kube.us-west-3a.k8s.cloud.apple.com (Postfix) with ESMTPSA id 8979C18013F8;
Thu, 20 Mar 2025 12:30:05 +0000 (UTC)
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Subject: Re: [EXTERNAL] - Re: Brunel - 2024 taxes
Date: Thu, 20 Mar 2025 07:29:27 -0500
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Topic:
App & System Services
SubTopic:
iCloud & Data
Greetings i have an app that uses three different SwiftData models and i want to know what is the best way to use the them accross the app. I though a centralized behaviour and i want to know if it a correct approach.First let's suppose that the first view of the app will load the three models using the @Enviroment that work with @Observation. Then to other views that add data to the swiftModels again with the @Environment. Another View that will use the swiftData models with graph and datas for average and min and max.Is this a corrent way? or i should use @Query in every view that i want and ModelContext when i add the data.
@Observable
class CentralizedDataModels {
var firstDataModel: [FirstDataModel] = []
var secondDataModel: [SecondDataModel] = []
var thirdDataModel: [ThirdDataModel] = []
let context: ModelContext
init(context:ModelContext) {
self.context = context
}
}
I have a new app I am working on, it uses, a container id like com.me.mycompany.FancyApp.prod, the description in the app is My Fancy App. When I deploy the app via TestFlight on a real device, the sync seems to work, but when I view iCloud->Storage-List, I see my app icon, and the name "prod". Where did the name prod come from? It should be My Fancy App, which is the actual name of the App.
I have an iOS app using SwiftData with VersionedSchema. The schema is synchronized with an CloudKit container.
I previously introduced some model properties that I have now removed, as they are no longer needed. This results in the current schema version being identical to one of the previous ones (except for its version number).
This results in the following exception:
'NSInvalidArgumentException', reason: 'Duplicate version checksums across stages detected.'
So it looks like we cannot have a newer schema version with an identical content to an older schema version.
The intuitive way would be to re-add the old (identical) schema version to the end of the "schemas" list property in the SchemaMigrationPlan, in order to signal that it is the newest one, and to add a migration stage back to it, thus:
public enum MySchemaMigrationPlan: SchemaMigrationPlan {
public static var schemas: [any VersionedSchema.Type] {
[
SchemaV100.self,
SchemaV101.self,
SchemaV100.self
]
}
public static var stages: [MigrationStage] {
[
migrateV100toV101,
migrateV101toV100
]
}
However, I am not sure if this is the right way to go, as previously, as I wanted to write unit tests for schema migration and rollback, I tried defining an inverse for each migration stage, so that I could trigger a migration and a rollback from a unit test, which resulted in an exception saying that it is not supported to downgrade a VersionedSchema.
I must admit that I solved the original problem by introducing a dummy model property that I will later remove. What would have been the correct approach?
I am trying to add a custom JSON DataStore and DataStoreConfiguration for SwiftData. Apple kindly provided some sample code in the WWDC24 session, "Create a custom data store with SwiftData", and (once updated for API changes since WWDC) that works fine.
However, when I try to add a relationship between two classes, it fails. Has anyone successfully made a JSONDataStore with a relationship?
Here's my code; firstly the cleaned up code from the WWDC session:
import SwiftData
final class JSONStoreConfiguration: DataStoreConfiguration {
typealias Store = JSONStore
var name: String
var schema: Schema?
var fileURL: URL
init(name: String, schema: Schema? = nil, fileURL: URL) {
self.name = name
self.schema = schema
self.fileURL = fileURL
}
static func == (lhs: JSONStoreConfiguration, rhs: JSONStoreConfiguration) -> Bool {
return lhs.name == rhs.name
}
func hash(into hasher: inout Hasher) {
hasher.combine(name)
}
}
final class JSONStore: DataStore {
typealias Configuration = JSONStoreConfiguration
typealias Snapshot = DefaultSnapshot
var configuration: JSONStoreConfiguration
var name: String
var schema: Schema
var identifier: String
init(_ configuration: JSONStoreConfiguration, migrationPlan: (any SchemaMigrationPlan.Type)?) throws {
self.configuration = configuration
self.name = configuration.name
self.schema = configuration.schema!
self.identifier = configuration.fileURL.lastPathComponent
}
func save(_ request: DataStoreSaveChangesRequest<DefaultSnapshot>) throws -> DataStoreSaveChangesResult<DefaultSnapshot> {
var remappedIdentifiers = [PersistentIdentifier: PersistentIdentifier]()
var serializedData = try read()
for snapshot in request.inserted {
let permanentIdentifier = try PersistentIdentifier.identifier(for: identifier,
entityName: snapshot.persistentIdentifier.entityName,
primaryKey: UUID())
let permanentSnapshot = snapshot.copy(persistentIdentifier: permanentIdentifier)
serializedData[permanentIdentifier] = permanentSnapshot
remappedIdentifiers[snapshot.persistentIdentifier] = permanentIdentifier
}
for snapshot in request.updated {
serializedData[snapshot.persistentIdentifier] = snapshot
}
for snapshot in request.deleted {
serializedData[snapshot.persistentIdentifier] = nil
}
try write(serializedData)
return DataStoreSaveChangesResult<DefaultSnapshot>(for: self.identifier, remappedIdentifiers: remappedIdentifiers)
}
func fetch<T>(_ request: DataStoreFetchRequest<T>) throws -> DataStoreFetchResult<T, DefaultSnapshot> where T : PersistentModel {
if request.descriptor.predicate != nil {
throw DataStoreError.preferInMemoryFilter
} else if request.descriptor.sortBy.count > 0 {
throw DataStoreError.preferInMemorySort
}
let objs = try read()
let snapshots = objs.values.map({ $0 })
return DataStoreFetchResult(descriptor: request.descriptor, fetchedSnapshots: snapshots, relatedSnapshots: objs)
}
func read() throws -> [PersistentIdentifier : DefaultSnapshot] {
if FileManager.default.fileExists(atPath: configuration.fileURL.path(percentEncoded: false)) {
let decoder = JSONDecoder()
decoder.dateDecodingStrategy = .iso8601
let data = try decoder.decode([DefaultSnapshot].self, from: try Data(contentsOf: configuration.fileURL))
var result = [PersistentIdentifier: DefaultSnapshot]()
data.forEach { s in
result[s.persistentIdentifier] = s
}
return result
} else {
return [:]
}
}
func write(_ data: [PersistentIdentifier : DefaultSnapshot]) throws {
let encoder = JSONEncoder()
encoder.dateEncodingStrategy = .iso8601
encoder.outputFormatting = [.prettyPrinted, .sortedKeys]
let jsonData = try encoder.encode(data.values.map({ $0 }))
try jsonData.write(to: configuration.fileURL)
}
}
The data model classes:
import SwiftData
@Model
class Settings {
private(set) var version = 1
@Relationship(deleteRule: .cascade) var hack: Hack? = Hack()
init() {
}
}
@Model
class Hack {
var foo = "Foo"
var bar = 42
init() {
}
}
Container:
lazy var mainContainer: ModelContainer = {
do {
let url = // URL to file
let configuration = JSONStoreConfiguration(name: "Settings", schema: Schema([Settings.self, Hack.self]), fileURL: url)
return try ModelContainer(for: Settings.self, Hack.self, configurations: configuration)
}
catch {
fatalError("Container error: \(error.localizedDescription)")
}
}()
Load function, that saves a new Settings JSON file if there isn't an existing one:
@MainActor func loadSettings() {
let mainContext = mainContainer.mainContext
let descriptor = FetchDescriptor<Settings>()
let settingsArray = try? mainContext.fetch(descriptor)
print("\(settingsArray?.count ?? 0) settings found")
if let settingsArray, let settings = settingsArray.last {
print("Loaded")
} else {
let settings = Settings()
mainContext.insert(settings)
do {
try mainContext.save()
} catch {
print("Error saving settings: \(error)")
}
}
}
The save operation creates a JSON file, which while it isn't a format I would choose, is acceptable, though I notice that the "hack" property (the relationship) doesn't have the correct identifier.
When I run the app again to load the data, I get an error (that there wasn't room to include in this post).
Even if I change Apple's code to not assign a new identifier, so the relationship property and its pointee have the same identifier, it still doesn't load.
Am I doing something obviously wrong, or are relationships not supported in custom data stores?
I have a document based SwiftData app in which I would like to implement a persistent cache. For obvious reasons, I would not like to store the contents of the cache in the documents themselves, but in my app's data directory.
Is a use case, in which a document based SwiftData app uses not only the ModelContainers from the currently open files, but also a ModelContainer writing a database file in the app's documents directory (for cache, settings, etc.) supported?
If yes, how can you inject two different ModelContexts, one tied to the currently open file and one tied to the local database, into a SwiftUI view?
Description:
I'm experiencing a critical issue with SwiftData custom migrations where objects created during migration appear to be inserted successfully but aren't persisted or found by queries after migration completes. The migration logs show objects being created, but subsequent queries return zero results.
Problem Details:
I'm migrating from schema version V2 to V3, which involves:
Renaming Person class to GroupData
Keeping the same data structure but changing the class name
Using a custom migration stage to copy data from old to new schema
Migration Code:
swift
static let migrationV2toV3 = MigrationStage.custom(
fromVersion: LinkMapV2.self,
toVersion: LinkMapV3.self,
willMigrate: { context in
do {
let persons = try context.fetch(FetchDescriptor<LinkMapV2.Person>())
print("Found (persons.count) Person objects to migrate") // ✅ Shows 11 objects
for person in persons {
let newGroup = LinkMapV3.GroupData(
id: person.id, // Same UUID
name: person.name,
// ... other properties
)
context.insert(newGroup)
print("Inserted GroupData: '\(newGroup.name)'") // ✅ Confirms insertion
}
try context.save() // ✅ No error thrown
print("Successfully migrated \(persons.count) objects") // ✅ Confirms save
} catch {
print("Migration error: \(error)")
}
},
didMigrate: { context in
do {
let groups = try context.fetch(FetchDescriptor<LinkMapV3.GroupData>())
print("Final GroupData count: \(groups.count)") // ❌ Shows 0 objects!
} catch {
print("Verification error: \(error)")
}
}
)
Console Output:
text
=== MIGRATION STARTED ===
Found 11 Person objects to migrate
Migrating Person: 'Riverside of pipewall' with ID: 7A08C633-4467-4F52-AF0B-579545BA88D0
Inserted new GroupData: 'Riverside of pipewall'
... (all 11 objects processed) ...
=== MIGRATION COMPLETED ===
Successfully migrated 11 Person objects to GroupData
=== MIGRATION VERIFICATION ===
New GroupData count: 0 // ❌ PROBLEM: No objects found!
What I've Tried:
Multiple context approaches:
Using the provided migration context
Creating a new background context with ModelContext(context.container)
Using context.performAndWait for thread safety
Different save strategies:
Calling try context.save() after insertions
Letting SwiftData handle saving automatically
Multiple save calls at different points
Verification methods:
Checking in didMigrate closure
Checking in app's ContentView after migration completes
Using both @Query and manual FetchDescriptor
Schema variations:
Direct V2→V3 migration
Intermediate V2.5 schema with both classes
Lightweight migration with @Attribute(originalName:)
Current Behavior:
Migration runs without errors
Objects appear to be inserted successfully
context.save() completes without throwing errors
But queries in didMigrate and post-migration return empty results
The objects seem to exist in a temporary state that doesn't persist
Expected Behavior:
Objects created during migration should be persisted and queryable
Post-migration queries should return the migrated objects
Data should be available in the main app after migration completes
Environment:
Xcode 16.0+
iOS 18.0+
SwiftData
Swift 6.0+
Key Questions:
Is there a specific way migration contexts should be handled for data to persist?
Are there known issues with object persistence in custom migrations?
Should we be using a different approach for class renaming migrations?
Is there a way to verify that objects are actually being written to the persistent store?
The migration appears to work perfectly until the verification step, where all created objects seem to vanish. Any guidance would be greatly appreciated!
Additional Context from my investigation:
I've noticed these warning messages during migration that might be relevant:
text
SwiftData.ModelContext: Unbinding from the main queue. This context was instantiated on the main queue but is being used off it.
error: Persistent History (76) has to be truncated due to the following entities being removed: (Person)
This suggests there might be threading or context lifecycle issues affecting persistence.
Let me know if you need any additional information about my setup or migration configuration!
According to my experiments SwiftData does not work with model attributes of primitive type UInt64. More precisely, it crashes in the getter of a UInt64 attribute invoked on an object fetched from the data store.
With Core Data persistent UInt64 attributes are not a problem. Does anyone know whether SwiftData will ever support UInt64?
Hi,
I am experiencing main thread freezes from fetching on Main Actor. Attempting to move the function to a background thread, but whenever I reference the TestModel in a nonisolated context or in another model actor, I get this warning:
Main actor-isolated conformance of 'TestModel' to 'PersistentModel' cannot be used in actor-isolated context; this is an error in the Swift 6 language mode
Is there a way to do this correctly?
Recreation, warning on line 13:
class TestModel {
var property: Bool = true
init() {}
}
struct SendableTestModel: Sendable {
let property: Bool
}
@ModelActor
actor BackgroundActor {
func fetch() throws -> [SendableTestModel] {
try modelContext.fetch(FetchDescriptor<TestModel>()).map { SendableTestModel(property: $0.property) }
}
}
Hi. I am having this error when trying to write to CloudKit public database.
<CKError 0x600000dbc4e0: "Permission Failure" (10/2007); server message = "Invalid bundle ID for container";
On app launch, I check for account status and ensure that the correct bundle identifier and container is being used. When the account status is checked, I do get the correct bundle id and container id printed in the console but trying to read or write to the container would throw that "Invalid bundle ID for container" error.
private init() {
container = CKContainer.default()
publicDB = container.publicCloudDatabase
// Check iCloud account status
checkAccountStatus()
}
func checkAccountStatus() {
print("🔍 CloudKit Debug:")
print("🔍 Bundle identifier from app: (Bundle.main.bundleIdentifier ?? "unknown")")
print("🔍 Container identifier: (container.containerIdentifier ?? "unknown")")
container.accountStatus { [weak self] status, error in
DispatchQueue.main.async {
switch status {
case .available:
self?.isSignedIn = true
self?.fetchUserID()
case .noAccount, .restricted, .couldNotDetermine:
self?.isSignedIn = false
self?.errorMessage = "Please sign in to iCloud in Settings to use this app."
default:
self?.isSignedIn = false
self?.errorMessage = "Unknown iCloud account status."
}
print("User is signed into iCloud: \(self?.isSignedIn ?? false)")
print("Account status: \(status.rawValue)")
}
}
}
I have tried:
Creating a new container
Unselecting and selecting the container in signing & capabilities
Unselecting and selecting the container in App ID Configuration
I used to have swift data models in my code and read that swift data is not compatible with CloudKit public data so I removed all the models and any swift data codes and only uses CloudKit public database.
let savedRecord = try await publicDB.save(record)
Nothing seems to work. If anyone could help please?
Rgds,
Hans
Topic:
App & System Services
SubTopic:
iCloud & Data
Tags:
CloudKit
Cloud and Local Storage
CloudKit Console
If use a SortDescriptor for a model and sort by some attribute from a relationship, in DEBUG mode it all works fine and sorts. However, in release mode, it is an instant crash.
SortDescriptor(.name, order: .reverse) ---- works
SortDescriptor(.assignedUser?.name, order: .reverse) ---- works in debug but crash in release.
What is the issue here, is it that SwiftData just incompetent to do this?
Hi everyone,
Im trying to set up CloudKit for my Unreal Engine 5.4 project but seem to be hitting some roadblocks on how to set up the Record Types.
From my understanding I need to set up a "file" record type with a "contents" asset field - but even with this it doesn't seem to work :(
Any unreal engine devs with some experience on this who could help me out?
Thanks!
I'm looking for guidance how to mitigate this crash. It seems super deep inside Core Data' FRC fetchedObjects management.
In my code, it's initiated by this
viewContext.perform {
[unowned self] in
self.viewContext.mergeChanges(fromContextDidSave: notification)
}
which is directly followed by the stack trace below.
Basically merging data from .NSManagedObjectContextDidSave notification from another NSManagedObjectContext. Nothing special, it works great for years, apart from these rare occurrences.
Exception Type: EXC_CRASH (SIGABRT)
Exception Codes: 0x0000000000000000, 0x0000000000000000
Exception Reason: -[__NSCFArray objectAtIndex:]: index (235) beyond bounds (234)
Termination Reason: SIGNAL 6 Abort trap: 6
Triggered by Thread: 0
Last Exception Backtrace:
0 CoreFoundation 0x199e947cc __exceptionPreprocess + 164 (NSException.m:249)
1 libobjc.A.dylib 0x1971672e4 objc_exception_throw + 88 (objc-exception.mm:356)
2 CoreFoundation 0x199fc4258 _NSArrayRaiseBoundException + 368 (NSCFArray.m:22)
3 CoreFoundation 0x199e288a4 -[__NSCFArray objectAtIndex:] + 200 (NSCFArray.m:42)
4 CoreData 0x1a1e17338 -[_PFMutableProxyArray objectAtIndex:] + 40 (_PFArray.m:1860)
5 CoreData 0x1a1e1673c -[NSFetchedResultsController _updateFetchedObjectsWithInsertChange:] + 380 (NSFetchedResultsController.m:1582)
6 CoreData 0x1a1e1426c __82-[NSFetchedResultsController(PrivateMethods) _core_managedObjectContextDidChange:]_block_invoke + 2240 (NSFetchedResultsController.m:2171)
7 CoreData 0x1a1dcdf80 developerSubmittedBlockToNSManagedObjectContextPerform + 156 (NSManagedObjectContext.m:4002)
8 CoreData 0x1a1e41a44 -[NSManagedObjectContext performBlockAndWait:] + 216 (NSManagedObjectContext.m:4113)
9 CoreData 0x1a1e41034 -[NSFetchedResultsController _core_managedObjectContextDidChange:] + 124 (NSFetchedResultsController.m:2379)
10 CoreFoundation 0x199e632f4 __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 148 (CFNotificationCenter.c:701)
11 CoreFoundation 0x199e63210 ___CFXRegistrationPost_block_invoke + 88 (CFNotificationCenter.c:194)
12 CoreFoundation 0x199e63158 _CFXRegistrationPost + 436 (CFNotificationCenter.c:222)
13 CoreFoundation 0x199e6170c _CFXNotificationPost + 728 (CFNotificationCenter.c:1248)
14 Foundation 0x198a84ea4 -[NSNotificationCenter postNotificationName:object:userInfo:] + 92 (NSNotification.m:531)
15 CoreData 0x1a1e11650 -[NSManagedObjectContext _createAndPostChangeNotification:deletions:updates:refreshes:deferrals:wasMerge:] + 1736 (NSManagedObjectContext.m:8098)
16 CoreData 0x1a1e10e0c -[NSManagedObjectContext _postRefreshedObjectsNotificationAndClearList] + 164 (NSManagedObjectContext.m:7631)
17 CoreData 0x1a1e0fad8 -[NSManagedObjectContext _processRecentChanges:] + 100 (NSManagedObjectContext.m:7714)
18 CoreData 0x1a1e3563c -[NSManagedObjectContext _coreMergeChangesFromDidSaveDictionary:usingObjectIDs:withClientQueryGeneration:] + 3436 (NSManagedObjectContext.m:3723)
19 CoreData 0x1a1e34350 __116+[NSManagedObjectContext(_NSCoreDataSPI) _mergeChangesFromRemoteContextSave:intoContexts:withClientQueryGeneration:]_block_invoke_4 + 76 (NSManagedObjectContext.m:9531)
20 CoreData 0x1a1dcdf80 developerSubmittedBlockToNSManagedObjectContextPerform + 156 (NSManagedObjectContext.m:4002)
21 CoreData 0x1a1e41a44 -[NSManagedObjectContext performBlockAndWait:] + 216 (NSManagedObjectContext.m:4113)
22 CoreData 0x1a1e39880 +[NSManagedObjectContext _mergeChangesFromRemoteContextSave:intoContexts:withClientQueryGeneration:] + 2372 (NSManagedObjectContext.m:9537)
23 CoreData 0x1a1e344a0 -[NSManagedObjectContext mergeChangesFromContextDidSaveNotification:] + 292 (NSManagedObjectContext.m:0)
Topic:
App & System Services
SubTopic:
iCloud & Data