My project is using swiftData and I want to implement iCloud sync in it. Now, my data base doesnt have any optional attributes or relationships and CloudKit wants them to be optional.
So, rather than editing all code with unwrapping code for the optionals, how can I provide a bridge that does so in the last stage of actually saving to the store? Sort of, capture it in a proxy object before writing and after reading from the store.
Is there a neat way that can save a lot of debugging? I have code snippets from chat gpt and they are hard to debug. This is my first project in swiftUI.
Thanks.
Neerav
iCloud & Data
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I have an app which uses key-value storage and will not sync data past a certain size -- meaning that device "A" will send the data to the cloud but device "B" will never receive the updated data. Device "B" will receive the NSUbiquitousKeyValueStoreDidChangeExternallyNotification that the KVS changed but the data is empty.
The data in in the KVS is comprised of 4 keys, each containing a value of NSData generated by NSKeyedArchiver. The NSData is comprised of property-list data types (e.g. numbers, strings, dates, etc.)
I've verified that the KVS meets the limits of:
A total of 1 MB per app, with a per-key limit of 1 MB
A per-key value size limit of 1 MB, and a maximum of 1024 keys
A maximum length for key strings is 64 bytes using UTF8 encoding
Also, the app has never received an NSUbiquitousKeyValueStoreQuotaViolationChange notification.
Of the 4 keys, 3 of them contain no more than 30 KB of data each. However, one of the keys can contain as much as 160 KB of data which will not sync to another device. Strangely, if I constrain the data to 100 KB it will work, however, that is not ideal as it is a fraction of the necessary data.
I don't see any errors in the debug log either.
Any suggestions on what to try next to get this working?
Some users of my app are reporting total loss of data while using the app.
This is happening specifically when they enable iCloud sync.
I am doing following
private func setupContainer(enableICloud: Bool) {
container = NSPersistentCloudKitContainer(name: "")
container.viewContext.automaticallyMergesChangesFromParent = true
container.viewContext.mergePolicy = NSMergeByPropertyObjectTrumpMergePolicy
guard let description: NSPersistentStoreDescription = container.persistentStoreDescriptions.first else {
fatalError()
}
description.setOption(true as NSNumber, forKey: NSPersistentHistoryTrackingKey)
description.setOption(true as NSNumber, forKey: NSPersistentStoreRemoteChangeNotificationPostOptionKey)
if enableICloud == false {
description.cloudKitContainerOptions = nil
}
container.loadPersistentStores { description, error in
if let error {
// Handle error
}
}
}
When user clicks on Toggle to enable/disable iCloud sync I just set the description.cloudKitContainerOptions to nil and then user is asked to restart the app.
Apart from that I periodically run the clear history
func deleteTransactionHistory() {
let sevenDaysAgo = Calendar.current.date(byAdding: .day, value: -7, to: Date())!
let purgeHistoryRequest = NSPersistentHistoryChangeRequest.deleteHistory(before: sevenDaysAgo)
let backgroundContext = container.newBackgroundContext()
backgroundContext.performAndWait {
try! backgroundContext.execute(purgeHistoryRequest)
}
}
I am an individual developer, and I want to create a demo. Do I need to develop an app for both iOS and Android to accomplish this?
Has Apple provided a simple demo or not?
Topic:
App & System Services
SubTopic:
iCloud & Data
I have a simple app that makes an HTTPS call to gather some JSON which I then parse and add to my SwiftData database. The app then uses a simple @Query in a view to get the data into a list.
on iOS 16 this works fine. No problems. But the same code on iOS 26 (targeting iOS 18.5) crashes after about 15 seconds of idle time after the list is populated. The error message is:
Could not cast value of type '__NSCFNumber' (0x1f31ee568) to 'NSString' (0x1f31ec718).
and occurs when trying to access ANY property of the list.
I have a stripped down version of the app that shows the crash available.
To replicate the issue:
open the project in Xcode 26
target any iOS 26 device or simulator
compile and run the project.
after the list is displayed, wait about 15 seconds and the app crashes.
It is also of note that if you try to run the app again, it will crash immediately, unless you delete the app from the device.
Any help on this would be appreciated.
Feedback number FB20295815 includes .zip file
Below is the basic code (without the data models)
The Best Seller List.Swift
import SwiftUI
import SwiftData
@main
struct Best_Seller_ListApp: App {
var body: some Scene {
WindowGroup {
ContentView()
}
.modelContainer (for: NYTOverviewResponse.self)
}
}
ContentView.Swift
import os.log
import SwiftUI
struct ContentView: View {
@Environment(\.modelContext) var modelContext
@State private var listEncodedName = String()
var body: some View {
NavigationStack () {
ListsView()
}
.task {
await getBestSellerLists()
}
}
func getBestSellerLists() async {
guard let url = URL(string: "https://api.nytimes.com/svc/books/v3/lists/overview.json?api-key=\(NYT_API_KEY)") else {
Logger.errorLog.error("Invalid URL")
return
}
do {
let decoder = JSONDecoder()
var decodedResponse = NYTOverviewResponse()
//decode the JSON
let (data, _) = try await URLSession.shared.data(from: url)
decoder.keyDecodingStrategy = .convertFromSnakeCase
decodedResponse = try decoder.decode(NYTOverviewResponse.self, from: data)
//remove any lists that don't have list_name_encoded. Fixes a bug in the data
decodedResponse.results!.lists = decodedResponse.results!.lists!.filter { $0.listNameEncoded != "" }
// sort the lists
decodedResponse.results!.lists!.sort { (lhs, rhs) -> Bool in
lhs.displayName < rhs.displayName
}
//delete any potential existing data
try modelContext.delete(model: NYTOverviewResponse.self)
//add the new data
modelContext.insert(decodedResponse)
} catch {
Logger.errorLog.error("\(error.localizedDescription)")
}
}
}
ListsView.Swift
import os.log
import SwiftData
import SwiftUI
@MainActor
struct ListsView: View {
//MARK: - Variables and Constants
@Query var nytOverviewResponses: [NYTOverviewResponse]
enum Updated: String {
case weekly = "WEEKLY"
case monthly = "MONTHLY"
}
//MARK: - Main View
var body: some View {
List {
if nytOverviewResponses.isEmpty {
ContentUnavailableView("No lists yet", systemImage: "list.bullet", description: Text("NYT Bestseller lists not downloaded yet"))
} else {
WeeklySection
MonthlySection
}
}
.navigationBarTitle("Bestseller Lists", displayMode: .large)
.listStyle(.grouped)
}
var WeeklySection: some View {
let rawLists = nytOverviewResponses.last?.results?.lists ?? []
// Build a value-typed array to avoid SwiftData faulting during sort
let weekly = rawLists
.filter { $0.updateFrequency == Updated.weekly.rawValue }
.map { (name: $0.displayName, encoded: $0.listNameEncoded, model: $0) }
.sorted { $0.name < $1.name }
return Section(header: Text("Weekly lists to be published on \(nytOverviewResponses.last?.results?.publishedDate ?? "-")")) {
ForEach(weekly, id: \.encoded) { item in
Text(item.name).font(Font.custom("Georgia", size: 17))
}
}
}
var MonthlySection: some View {
let rawLists = nytOverviewResponses.last?.results?.lists ?? []
// Build a value-typed array to avoid SwiftData faulting during sort
let monthly = rawLists
.filter { $0.updateFrequency == Updated.monthly.rawValue }
.map { (name: $0.displayName, encoded: $0.listNameEncoded, model: $0) }
.sorted { $0.name < $1.name }
return Section(header: Text("Monthly lists to be published on \(nytOverviewResponses.last?.results?.publishedDate ?? "-")")) {
ForEach(monthly, id: \.encoded) { item in
Text(item.name).font(Font.custom("Georgia", size: 17))
}
}
}
}
I have tried to set up iCloud sync. Despite fully isolating and resetting my development environment, the app fails with:
NSCocoaErrorDomain Code=134060 (PersistentStoreIncompatibleVersionHashError)
What I’ve done:
Created a brand new CloudKit container
Created a new bundle ID and app target
Renamed the Core Data model file itself
Set a new model version
Used a new .sqlite store path
Created a new .entitlements file with the correct container ID
Verified that the CloudKit dashboard shows no records
Deleted and reinstalled the app on a real device
Also tested with “Automatically manage signing” and without
Despite this, the error persists. I am very inexperienced and am not sure what my next step is to even attempt to fix this. Any guidance is apprecitated.
It takes a few seconds, sometimes a few minutes for records to be downloaded back from CloudKit when the user reinstalls the app, which leads users to thinking their data was lost. I would like to know if there’s any way to provide a visual feedback about the current CloudKit sync status so I can let users know their data is being in fact downloaded back to their devices.
anyone getting the following error with CloudKit+CoreData on iOS16 RC?
delete/resintall app, delete user CloudKit data and reset of environment don't fix.
[error] error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _requestAbortedNotInitialized:](2044): <NSCloudKitMirroringDelegate: 0x2816f89a0> - Never successfully initialized and cannot execute request '<NSCloudKitMirroringImportRequest: 0x283abfa00> 41E6B8D6-08C7-4C73-A718-71291DFA67E4' due to error: Error Domain=NSCocoaErrorDomain Code=4864 "*** -[NSKeyedUnarchiver _initForReadingFromData:error:throwLegacyExceptions:]: incomprehensible archive (0x53, 0x6f, 0x6d, 0x65, 0x20, 0x65, 0x78, 0x61)" UserInfo={NSDebugDescription=*** -[NSKeyedUnarchiver _initForReadingFromData:error:throwLegacyExceptions:]: incomprehensible archive (0x53, 0x6f, 0x6d, 0x65, 0x20, 0x65, 0x78, 0x61)}
Hi, I am building an iOS app with SwiftUI and SwiftData for the first time and I am experiencing a lot of difficulty with this error:
Thread 44: Fatal error: Never access a full future backing data - PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(backing: SwiftData.PersistentIdentifier.PersistentIdentifierBacking.managedObjectID(<ID> <x-coredata://<UUID>/MySwiftDataModel/p1>)), backing: SwiftData.PersistentIdentifier.PersistentIdentifierBacking.managedObjectID(<ID> <x-coredata://<UUID>/MySwiftDataModel/p1>)) with Optional(<UUID>)
I have been trying to figure out what the problem is, but unfortunately I cannot find any information in the documentation or on other sources online. My only theory about this error is that it is somehow related to fetching an entity that has been created in-memory, but not yet saved to the modelContext in SwiftData.
However, when I am trying to debug this, it's not clear this is the case. Sometimes the error happens, sometimes it doesn't. Saving manually does not always solve the error.
Therefore, it would be extremely helpful if someone could explain what this error means and whether there are any best practices to do with SwiftData, or some pitfalls to avoid (such as wrapping my model context into a repository class).
To be clear, this problem is NOT related to one area of my code, it happens throughout my app, at unpredictable places and time. Given that there is very little information related to this error, I am at a loss at how to make sure that this never happens.
This question has been asked on the forum here as well as on StackOverflow, Reddit (can't link that here), but none of the answers worked for me.
For reference, my models generally look like this:
import Foundation
import SwiftData
@Model
final class MySwiftDataModel {
// Stable cross-device identity
@Attribute(.unique)
var uuid: UUID
var someNumber: Int
var someString: String
@Relationship(deleteRule: .nullify, inverse: \AnotherSwiftDataModel.parentModel)
var childModels: [AnotherSwiftDataModel]
init(uuid: UUID = UUID(), someNumber: Int = 1, someString: String = "Some", childModels: [AnotherSwiftDataModel] = []) {
self.uuid = uuid
self.someNumber = someNumber
self.someString = someString
self.childModels = childModels
}
func addChildModel(model: AnotherSwiftDataModel) {
self.childModels.append(model)
}
func removeChildModel(by id: PersistentIdentifier) {
self.childModels = self.childModels.filter { $0.id != id }
}
}
and the child model:
import Foundation
import SwiftData
@Model
final class AnotherSwiftDataModel {
// Stable cross-device identity
@Attribute(.unique)
var uuid: UUID
var someNumber: Int
var someString: String
var parentModel: MySwiftDataModel?
init(uuid: UUID = UUID(), someNumber: Int = 1, someString: String = "Some") {
self.uuid = uuid
self.someNumber = someNumber
self.someString = someString
}
}
For now, you can assume I am not using CloudKit - i know for a fact the error is unrelated to CloudKit, because it happens when I am not using CloudKit (so I do not need to follow CloudKit's requirements for model design, such as nullable values etc).
As I said, the error surfaces at different times - sometimes during assignments, a lot of times during deletions of related models, etc.
Could you please explain what I am doing wrong and how I can make sure that this error does not happen? What are the architectural patterns that work best for SwiftData in this case? Do you have any examples of things I should avoid?
Thanks
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
}
}
For a CRM application, I want users to be able to switch between accounts and have their saved contacts stored locally. Whenever a user logs in, the app should fetch data from their specific database location.
What’s the best practice to achieve this?
Should I create a separate database for each user?
Should I store all the data in one database and filter it by user?
Or is there a better approach I should consider?
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 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?
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)
From: Marcel Brunel <sender_email_address>
Message-Id: <2E8D69EA-FCA6-4F5D-9D42-22A955C073F6@sender_domain>
Content-Type: multipart/alternative;
boundary="Apple-Mail=_F9AC7D29-8520-4B25-9362-950CB20ADEC5"
Mime-Version: 1.0 (Mac OS X Mail 16.0 (3826.400.131.1.6))
Subject: Re: [EXTERNAL] - Re: Brunel - 2024 taxes
Date: Thu, 20 Mar 2025 07:29:27 -0500
In-Reply-To: <SA0PR18MB350300DE7274C018F66EEA24F2D82@SA0PR18MB3503_namprd18_prod_outlook_com>
To: Troy Womack <recipient_email_address>
References: <SA0PR18MB350314D0B88E283C5C8E1BB6F2DE2@SA0PR18MB3503_namprd18_prod_outlook_com>
<9B337A3E-D373-48C5-816F-C1884BDA6F42@sender_domain>
<SA0PR18MB350341A7172E8632D018A910F2D82@SA0PR18MB3503_namprd18_prod_outlook_com>
<SA0PR18MB350300DE7274C018F66EEA24F2D82@SA0PR18MB3503_namprd18_prod_outlook_com>
X-Mailer: Apple Mail (2.3826.400.131.1.6)
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Topic:
App & System Services
SubTopic:
iCloud & Data
I would like to have a SwiftData predicate that filters against an array of PersistentIdentifiers.
A trivial use case could filtering Posts by one or more Categories. This sounds like something that must be trivial to do.
When doing the following, however:
let categoryIds: [PersistentIdentifier] = categoryFilter.map { $0.id }
let pred = #Predicate<Post> {
if let catId = $0.category?.persistentModelID {
return categoryIds.contains(catId)
} else {
return false
}
}
The code compiles, but produces the following runtime exception (XCode 26 beta, iOS 26 simulator):
'NSInvalidArgumentException', reason: 'unimplemented SQL generation for predicate : (TERNARY(item != nil, item, nil) IN {}) (bad LHS)'
Strangely, the same code works if the array to filter against is an array of a primitive type, e.g. String or Int.
What is going wrong here and what could be a possible workaround?
So i created an App and for some time it was working fine. The app has features to show pdf to users without logging in. I needed to upload all data to cloudkit on public database.
I was not having knowledge that there are 2 mode being a noob in coding so after i saved all records in development mode in cloudkit when i published my app, i was not able to see them (Reason because live mode works in Production mode).
So i need help now to transfer data from development mode to production mode or any app or code that can help me upload all data in production mode.
Topic:
App & System Services
SubTopic:
iCloud & Data
Tags:
CloudKit
CloudKit Dashboard
CloudKit Console
Hi. I'm hoping someone might be able to help us with an issue that's been affecting our standalone watchOS app for some time now.
We've encountered consistent crashes on Apple Watch devices when the app enters the background while the device is offline (i.e., no Bluetooth and no Wi-Fi connection). Through extensive testing, we've isolated the problem to the use of NSPersistentCloudKitContainer. When we switch to NSPersistentContainer, the crashes no longer occur.
Interestingly, this issue only affects our watchOS app. The same CloudKit-based persistence setup works reliably on our iOS and macOS apps, even when offline. This leads us to believe the issue may be specific to how NSPersistentCloudKitContainer behaves on watchOS when the device is disconnected from the network.
We're targeting watchOS 10 and above. We're unsure if this is a misconfiguration on our end or a potential system-level issue, and we would greatly appreciate any insight or guidance.
I have the following struct doing some simple tasks, running a network request and then saving items to Core Data.
Per Xcode 26's new default settings (onisolated(nonsending) & defaultIsolation set to MainActor), the struct and its functions run on the main actor, which works fine and I can even safely omit the context.perform call because of it, which is great.
struct DataHandler {
func importGames(withIDs ids: [Int]) async throws {
...
let context = PersistenceController.shared.container.viewContext
for game in games {
let newGame = GYGame(context: context)
newGame.id = UUID()
}
try context.save()
}
}
Now, I want to run this in a background thread to increase performance and responsiveness. So I followed this session (https://developer.apple.com/videos/play/wwdc2025/270) and believe the solution is to mark the struct as nonisolated and the function itself as @concurrent.
The function now works on a background thread, but I receive a crash: _dispatch_assert_queue_fail. This happens whether I wrap the Core Data calls with context.perform or not. Alongside that I get a few new warnings which I have no idea how to work around.
So, what am I doing wrong here? What's the correct way to solve this simple use case with Swift 6's new concurrency stuff and the default main actor isolation in Xcode 26?
Curiously enough, when setting onisolated(nonsending) to false & defaultIsolation to non isolating, mimicking the previous behavior, the function works without crashing.
nonisolated
struct DataHandler {
@concurrent
func importGames(withIDs ids: [Int]) async throws {
...
let context = await PersistenceController.shared.container.newBackgroundContext()
for game in games {
let newGame = GYGame(context: context)
newGame.id = UUID() // Main actor-isolated property 'id' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode
}
try context.save()
}
}
When creating a new project in Xcode 26, the default for defaultIsolation is MainActor.
Core Data creates classes for each entity using code gen, but now those classes are also internally marked as MainActor, which causes issues when accessing managed object from a background thread like this.
Is there a way to fix this warning or should Xcode actually mark these auto generated classes as nonisolated to make this better? Filed as FB13840800.
nonisolated
struct BackgroundDataHandler {
@concurrent
func saveItem() async throws {
let context = await PersistenceController.shared.container.newBackgroundContext()
try await context.perform {
let newGame = Item(context: context)
newGame.timestamp = Date.now // Main actor-isolated property 'timestamp' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode
try context.save()
}
}
}
Turning code gen off inside the model and creating it manually, with the nonisolated keyword, gets rid of the warning and still works fine. So I guess the auto generated class could adopt this as well?
public import Foundation
public import CoreData
public typealias ItemCoreDataClassSet = NSSet
@objc(Item)
nonisolated
public class Item: NSManagedObject {
}
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