I have an app that uses SwiftData with CloudKit to synchronize data across a users devices. I'm able to replicate data created on one device on another and when removing data, it is also removed on the other device. So, I know that SwiftData and CloudKit are configured correctly.
What I'd like to do though, is to ensure that if a user installs the app on an additional device, that the data is synchronized upon app start.
When testing my app on a third device, via TestFlight, there was no data in the app upon launch even though all three devices are using the same Apple account (e.g. Apple ID).
What is the best way to achieve this?
CloudKit
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Hi,
I am implementing the synchronisation of SwiftData with CloudKit as described in the Apple Documentation titled - "Syncing model data across a person’s devices." My app runs fine on iPhone without activating CloudKit under "Signing and Capabilities" option. But when activated, I get a CoreData error with a code: 134060. My app is in development stage. The following is the code snippet for your reference taken from the main structure adopting the App protocol.
init() {
do {
#if DEBUG
let schema = Schema([
Debit.self,
Credit.self,
])
let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false)
// Use an autorelease pool to make sure Swift deallocates the persistent
// container before setting up the SwiftData stack.
try autoreleasepool {
let desc = NSPersistentStoreDescription(url: modelConfiguration.url)
let opts = NSPersistentCloudKitContainerOptions(containerIdentifier: "iCloud.com.sureshco.MyFirstApp")
desc.cloudKitContainerOptions = opts
// Load the store synchronously so it completes before initializing the CloudKit schema.
desc.shouldAddStoreAsynchronously = false
if let mom = NSManagedObjectModel.makeManagedObjectModel(for: [
Debit.self,
Credit.self,
]) {
let container = NSPersistentCloudKitContainer(name: "MyFirstApp", 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)
}
}
}
#endif
sharedModelContainer = try ModelContainer(for: schema, configurations: [modelConfiguration])
} catch {
fatalError(error.localizedDescription)
}
}
Any help will be greatly appreciated!
Regards
Suresh.
I'm trying to add Cloud Kit integration to SwiftData app (that is already in the App Store, btw).
When the app is installed on devices that are directly connected to Xcode, it works (a bit slow, but pretty well).
But when the app is distributed to Testflight internal testers, the synchronization doesn't happen at all.
So, is this situation normal and how can I test apps with iCloud integration properly?
My macOS app is developed using SwfitUI, SwiftData, and CloudKit. In the development environment, CloudKit works well. Locally added models can be quickly viewed in the CloudKit Console. macOS app and iOS app with the same BundleID can also synchronize data normally when developing locally. However, in the production environment, the macOS app cannot synchronize data with iCloud. But iOS app can. The models added in the production environment are only saved locally and cannot be viewed in CloudKit Console Production.
I am sure I have configured correctly, container schema changes to deploy to the Production environment. I think there may be a problem with CloudKit in macOS.
Please help troubleshoot the problem. I can provide you with any information you need.
var body: some Scene {
WindowGroup {
MainView()
.frame(minWidth: 640, minHeight: 480)
.environment(mainViewModel)
}
.modelContainer(for: [NoteRecord.self])
}
I didn't do anything special. I didn’t do anything special. I just used SwiftData hosted by CloudKit.
Let's say I have a CloudKit database schema where I have records of type Author that are referenced by multiple records of type Article.
I want to delete an Author record if no Article is referencing it. Now consider the following conflict:
device A deleted the last Article referencing Author #42
device B uploads a new Article referencing Author #42 at the same time
The result should be that Author #42 is not deleted after both operations are finished. But both device don't know from each other changes. So either device B could miss that device A deleted the author. Or device A could have missed that a new Article was uploaded and therefore the Author #42 was deleted right after the upload of device B.
I though about using a reference count first. But this won't work if the ref count is part of the Author record. This is because deletions do not use the changeTag to detect lost updates: If device A found a reference count 0 and decides to delete the Author, it might miss that device B incremented the count meanwhile.
I currently see two alternatives:
Using a second record that outlives the Author to keep the reference count and using an atomic operation to update and delete it. So if the update fails, the delete would fail either.
Always adding a new child record to the Author whenever a reference is made. We could call it ReferenceToken. Since child records may not become dangling, CloudKit would stop a deletion, if a new ReferenceToken sets the parent reference to the Author.
Are there any better ways doing this?
How can I set the display name of the CloudKit container in Settings -> iCloud -> Manage Storage.
I have multiple containers, some legacy, and some for certain modules that are shared among a suite of apps. The problem is all Containers show the same name so it is not possible to advise a user which containers are safe to delete. I am using NSPersistentCloudKitContainer.
I'm using NSPersistentCloudKitContainer to save, edit, and delete items, but it only works half of the time. When I delete an item and terminate the app and repoen, sometimes the item is still there and sometimes it isn't. The operations are simple enough:
moc.delete(thing)
try? moc.save()
Here is my DataController. I'm happy to provide more info as needed
class DataController: ObservableObject {
let container: NSPersistentCloudKitContainer
@Published var moc: NSManagedObjectContext
init() {
container = NSPersistentCloudKitContainer(name: "AppName")
container.loadPersistentStores { description, error in
if let error = error {
print("Core Data failed to load: \(error.localizedDescription)")
}
}
#if DEBUG
do {
try container.initializeCloudKitSchema(options: [])
} catch {
print("Error initializing CloudKit schema: \(error.localizedDescription)")
}
#endif
moc = container.viewContext
}
}
The same macOS app is logged into the same iCloud account on two Macs. The apps on both devices can sync data with iCloud, but the data between them is isolated. When I was developing, I just enabled the CloudKit(SwiftData host in iCloud) capability and did not do anything special. I thought that the same app and the same iCloud account should sync the same data between different devices. Why is the cloud data on these two Macs isolated?
I have a CKRecord that references an CKAsset. If I understand it correctly, CKSyncEngine would download the asset every time the record has changed on the server. (Of course it would try to use the local asset cache, but worst-case it might be already flushed)
The documentation for CKAsset says that asset downloads can be prevented by limiting the requested record keys using the desiredKeys property on the fetch operation. But I don't see any possibility to set this property when using CKSyncEngine.
Did I miss something? Are there any alternatives?
Only development environment can real sync.
But product environment can't sync.
And when run my device show this error:
CoreData: Already have a mirrored relationship registered for this key: CD_M2M_Event_items:B269B612-37A6-4ED7-9FDB-601E88BF56A8:8DC64E4A-E893-4465-8B21-48CF1C52A4BC
<NSCKMirroredRelationship: 0x302bb9950> (entity: NSCKMirroredRelationship; id: 0xa049af3fb0190928 <x-coredata://BEB6E57C-891C-4E71-B92F-7BAA0844913E/NSCKMirroredRelationship/p1747>; data: {
cdEntityName = Event;
ckRecordID = "B5908A8A-079E-482C-9F2E-1309BF071F0E";
ckRecordSystemFields = nil;
isPending = 0;
isUploaded = 0;
needsDelete = 0;
recordName = "B269B612-37A6-4ED7-9FDB-601E88BF56A8";
recordZone = "0xa049af3f6a5909a8 <x-coredata://BEB6E57C-891C-4E71-B92F-7BAA0844913E/NSCKRecordZoneMetadata/p1>";
relatedEntityName = Item;
relatedRecordName = "8DC64E4A-E893-4465-8B21-48CF1C52A4BC";
relationshipName = items;
})
<decode: bad range for [%@] got [offs:941 len:665 within:0]>
And my product core data sync data only to October 24, 2024.
The data before October 24 was synchronized normally,
Nothing after October 24 is synced.
Hey there,
I’m feeling pretty desperate at this point, as my most recent update to Xcode 16.1 and the new 18.1 simulators has basically made it impossible for me to work on my apps.
The same app and same code run fine in the 18.0 simulators with the same iCloud account logged in.
I’ve tried multiple simulators with the same results, even on different computers. I’ve also tried logging in repeatedly without any luck. The CloudKit database logs don’t show any errors or suspicious entries. Reinstalling the app on the simulator doesn't help either.
Whenever I launch the application in Xcode, I'm getting:
error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _performSetupRequest:]_block_invoke(1240): <NSCloudKitMirroringDelegate: 0x600003d213b0>: Failed to set up CloudKit integration for store: <NSSQLCore: 0x103f124e0> (URL: file:///Users/kerstenbroich/Library/Developer/CoreSimulator/Devices/57BC78CE-DB2A-4AC0-9D7A-43C386305F56/data/Containers/Data/Application/EFDE9B05-0584-47C5-80AE-F2FF5994860C/Library/Application%20Support/Model.sqlite)
<CKError 0x600000d3dfe0: "Partial Failure" (2/1011); "Failed to modify some record zones"; partial errors: {
com.apple.coredata.cloudkit.zone:__defaultOwner__ = <CKError 0x600000d7c090: "Internal Error" (1/5000); "Failed user key sync">
}>
error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate recoverFromError:](2310): <NSCloudKitMirroringDelegate: 0x600003d213b0> - Attempting recovery from error: <CKError 0x600000d3dfe0: "Partial Failure" (2/1011); "Failed to modify some record zones"; partial errors: {
com.apple.coredata.cloudkit.zone:__defaultOwner__ = <CKError 0x600000d7c090: "Internal Error" (1/5000); "Failed user key sync">
}>
error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _recoverFromPartialError:forStore:inMonitor:]_block_invoke(2773): <NSCloudKitMirroringDelegate: 0x600003d213b0>: Found unknown error as part of a partial failure: <CKError 0x600000d7c090: "Internal Error" (1/5000); "Failed user key sync">
error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _recoverFromPartialError:forStore:inMonitor:](2820): <NSCloudKitMirroringDelegate: 0x600003d213b0>: Error recovery failed because the following fatal errors were found: {
"<CKRecordZoneID: 0x600000d62340; zoneName=com.apple.coredata.cloudkit.zone, ownerName=__defaultOwner__>" = "<CKError 0x600000d7c090: \"Internal Error\" (1/5000); \"Failed user key sync\">";
}
Any help/ideas would be much appreciated, because I have no clue what to try next.
Thanks a lot!
Is it possible to use CloudKit and add integrations, Google Drive for example. If possible, how?
I'm continually getting an error with a new CloudKit container when I try to save data.
error: Couldn't get container configuration from the server for container "iCloud.com.***.***"
here's the class:
private var db = CKContainer(identifier: "iCloud.com.***.***").privateCloudDatabase
func addTask(taskItem: TaskItem) async throws {
checkStatus()
do {
try await db.save(taskItem.record)
} catch {
print("error: \(error.localizedDescription)")
}
}
func checkStatus() {
let id = CKContainer(identifier: "iCloud.com.***.***").containerIdentifier
print(id ?? "unknown")
Task {
let status = try await CKContainer(identifier: "iCloud.com.***.***").accountStatus()
switch status {
case .available:
print("available")
case .noAccount:
print("no account")
case .restricted:
print("restricted")
case .couldNotDetermine:
print("could not determine")
case .temporarilyUnavailable:
print("temporarily unavailable")
@unknown default: break
}
}
}
The account status reports as available but gives the error on an attempt to save.. I'm trying to work out what I might be doing wrong..
Hello, I`m working on an app that uses CloudKit and CKShare, but the app has 2 different targets, one for professional and one for patients, and theoretically the target of the professional sends the CKShare and the target of the patient should accept, but the ckshare tries to always open the target of the profissional, I would like to know if the are any way to configure the CKShare to oppen the target od the patients
While reading CkSyncEngine demo project code, I don't find the code to remove items in syncEngine.state.pendingRecordZoneChanges explicitly. I suspect it might occur in two possible places: nextRecordZoneChangeBatch() or ``nextRecordZoneChangeBatch()`, but I can't figure out how it occurs.
nextRecordZoneChangeBatch() has the following code:
let batch = await CKSyncEngine.RecordZoneChangeBatch(pendingChanges: changes) { recordID in
if let contact = contacts[recordID.recordName] {
let record = contact.lastKnownRecord ?? CKRecord(recordType: Contact.recordType, recordID: recordID)
contact.populateRecord(record)
return record
} else {
// We might have pending changes that no longer exist in our database. We can remove those from the state.
syncEngine.state.remove(pendingRecordZoneChanges: [ .saveRecord(recordID) ])
return nil
}
}
(I'll ignore the syncEngine.state.remove(pendingRecordZoneChanges:) in the else clause, because it's unrelated)
Could it be that CKSyncEngine.RecordZoneChangeBatch.init(pendingChanges:,recordProvider:) automatically remove a CKRecord when the recordProvider: closure returns a non-nil value? I checked its document, but it doesn't say anything about this.
Thanks for any help.
I am getting the following error while trying to delete a Record Type in Dev container. How do I solve it?
invalid attempt to delete user record type
I have a quesiton on .accountChange handler code in CKSyncEngine demo project. Below is the code in handleAccountChange():
if shouldDeleteLocalData {
try? self.deleteLocalData() // This error should be handled, but we'll skip that for brevity in this sample app.
}
if shouldReUploadLocalData {
let recordZoneChanges: [CKSyncEngine.PendingRecordZoneChange] = self.appData.contacts.values.map { .saveRecord($0.recordID) }
self.syncEngine.state.add(pendingDatabaseChanges: [ .saveZone(CKRecordZone(zoneName: Contact.zoneName)) ])
self.syncEngine.state.add(pendingRecordZoneChanges: recordZoneChanges)
}
IMHO, when user switches account, the most important thing is to reload data from the new account's document folder. However, I can't see this is done anywhere. In above code, if shouldDeleteLocalData is false, self.appData would still hold the previous account's local data. That seems very wrong. Am I missing something?
It would be best if iOS restarts all applications when user switches account. If that's not the case (I guess so, otherwise there is no point to handle .accountChange in the app), I think application should implement an API to re-initialize itself.
EDIT: after looking at the code again, I realize that the following code makes sure shouldDeleteLocalData is always true when user switching accounts. So the code doesn't leak the previous account's data, though I still think it has an issue - it doesn't load the new account's data.
case .switchAccounts:
shouldDeleteLocalData = true
shouldReUploadLocalData = false
When using iCloud account with push in Apple mail app.
The badge number of unread email is not syncing across devices.
If I read an email on my iPhone my iPad mail app badge won’t update until I click into the app and wait for the update.
Is there any fix of this?
After upgrading to iOS 18, my Core Data stack using NSPersistentCloudKitContainer in a shared App Group container stopped syncing correctly. The persistent store configuration, which previously worked in iOS 17, now experiences delayed or missing sync updates between devices. Then the app freezes and writes terminal the same error detail (which I provided) too many times.
The debug logs from the CloudKit mirroring delegate (NSCloudKitMirroringDelegate) show repetitive notifications but no updates in persistent history. Additionally, the persistent history tracking key appears unresponsive to local changes, causing transactions to fail in updating or syncing as expected.
Key setup details:
Core Data is set up within an App Group container using NSPersistentCloudKitContainer.
NSPersistentHistoryTrackingKey and NSPersistentStoreRemoteChangeNotificationPostOptionKey options are set to true.
Any insights into changes in iOS 18 Core Data or CloudKit handling with NSPersistentCloudKitContainer, especially around history tracking and sync delays, would be greatly appreciated. Thank you.
Error Detail
file:///private/var/mobile/Containers/Shared/AppGroup/BF95D309-EBE9-485E-B5CE-AA17097F7B60/[AppName]Database.sqlite
CoreData: debug: CoreData+CloudKit: -[NSCloudKitMirroringDelegate managedObjectContextSaved:](3123): <NSCloudKitMirroringDelegate: 0x3032b4870>: Observed context save: <NSPersistentStoreCoordinator: 0x302694bd0> - <NSManagedObjectContext: 0x3036b1a00>
CoreData: debug: CoreData+CloudKit: -[NSCloudKitMirroringDelegate remoteStoreDidChange:](3166): <NSCloudKitMirroringDelegate: 0x3032b4870>: Observed remote store notification: <NSPersistentStoreCoordinator: 0x302694bd0> - 090C4244-0101-4DEF-90D6-1260570F47A5 - <NSPersistentHistoryToken - {
"090C4244-0101-4DEF-90D6-1260570F47A5" = 9;
}> -
Persistence.swift
struct PersistenceController {
let container: NSPersistentCloudKitContainer
static let shared = PersistenceController()
static var preview: PersistenceController = {PersistenceController()}()
init() {
container = NSPersistentCloudKitContainer(name: "[AppName]")
// Configure CloudKit for the default container
if let url = FileManager.default.containerURL(forSecurityApplicationGroupIdentifier: "group.com.[CompanyName].[AppName]") {
let storeURL = url.appendingPathComponent("[AppName]Database.sqlite")
let description = container.persistentStoreDescriptions.first
description?.url = storeURL
description?.setOption(true as NSNumber, forKey: NSPersistentHistoryTrackingKey)
description?.setOption(true as NSNumber, forKey: NSPersistentStoreRemoteChangeNotificationPostOptionKey)
container.persistentStoreDescriptions = [description].compactMap { $0 }
}
container.loadPersistentStores { (storeDescription, error) in
if let error = error as NSError? {
fatalError("Unresolved error \(error), \(error.userInfo)")
}
}
container.viewContext.automaticallyMergesChangesFromParent = true
container.viewContext.mergePolicy = NSMergeByPropertyObjectTrumpMergePolicy
}
}
In CloudKit console, i have a key named "Name" with String data type and i want to filter my query by that key. I can only query two record with name "Star" and "Kaizen", and i can't query the rest of the records. Can you help me with that.