Hi, I'm developing an app for iOS and MacOS with SwiftData and CloudKit syncing. I had sync working very well with a set of models. This schema was also pushed to CloudKit production. Last week I added several models, and several relationship properties linking my existing models to newly added models. The schema updated just fine and everything worked. Then things went sideways: earlier this week I decided I wanted to rename a property on one of my new models. So I renamed the property, removed the application support folder for my local debug app (on Mac OS), removed the app from the iOS Simulator (to clear its local database), and finally reset my CloudKit container to its Production schema. Basically, I tried to go back to the same state I had as when I first added the new models. However, this time things don't go so smoothly, even after starting the app several times, rebooting my machine, turning iCloud on and off in Xcode and MacOS and iOS. When I look in CloudKit console, I see only my old models there: none of the new ones are added. I'd love some pointers on how I can best debug this issue, as I feel completely stuck. On MacOS I have very little mac-logs.txt to go on. Since the logs are a bit lengthy I've added them as an attachment. I get a few warnings, but it is unclear what they are warning me about. One thing that does stand out is that I am running the CloudKit in Development mode here. However, the logs do state accountPartition=Prod . And when I query CKContainer.default() for the container environment, the response is sandbox, which matches Development! On iOS The logs show a few errors, but I cannot make sense of them. error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _performSetupRequest:]_block_invoke(1240): <NSCloudKitMirroringDelegate: 0x600003d09860>: Failed to set up CloudKit integration for store: <NSSQLCore: 0x103325c90> (URL: file:///Users/bastiaan/Library/Developer/CoreSimulator/Devices/BF847CE5-A3E2-4B4C-8CD5-616B75B29AFE/data/Containers/Data/Application/0A916F67-B9B2-457B-8FA7-8C42819EA9AA/Library/Application%20Support/default.store) <CKError 0x600000c433f0: "Partial Failure" (2/1011); "Failed to modify some record zones"; partial errors: { com.apple.coredata.cloudkit.zone:__defaultOwner__ = <CKError 0x600000c956b0: "Internal Error" (1/5005); "Couldn't create new PCS blob for zone <CKRecordZoneID: 0x600000c475d0; zoneName=com.apple.coredata.cloudkit.zone, ownerName=__defaultOwner__>"> }> error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate recoverFromError:](2310): <NSCloudKitMirroringDelegate: 0x600003d09860> - Attempting recovery from error: <CKError 0x600000c433f0: "Partial Failure" (2/1011); "Failed to modify some record zones"; partial errors: { com.apple.coredata.cloudkit.zone:__defaultOwner__ = <CKError 0x600000c956b0: "Internal Error" (1/5005); "Couldn't create new PCS blob for zone <CKRecordZoneID: 0x600000c475d0; zoneName=com.apple.coredata.cloudkit.zone, ownerName=__defaultOwner__>"> }> error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _recoverFromPartialError:forStore:inMonitor:]_block_invoke(2773): <NSCloudKitMirroringDelegate: 0x600003d09860>: Found unknown error as part of a partial failure: <CKError 0x600000c956b0: "Internal Error" (1/5005); "Couldn't create new PCS blob for zone <CKRecordZoneID: 0x600000c475d0; zoneName=com.apple.coredata.cloudkit.zone, ownerName=__defaultOwner__>"> error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _recoverFromPartialError:forStore:inMonitor:](2820): <NSCloudKitMirroringDelegate: 0x600003d09860>: Error recovery failed because the following fatal errors were found: { "<CKRecordZoneID: 0x600000c8fd50; zoneName=com.apple.coredata.cloudkit.zone, ownerName=__defaultOwner__>" = "<CKError 0x600000c956b0: \"Internal Error\" (1/5005); \"Couldn't create new PCS blob for zone <CKRecordZoneID: 0x600000c475d0; zoneName=com.apple.coredata.cloudkit.zone, ownerName=__defaultOwner__>\">"; } And in CloudKit logs I see: 06/11/2024, 9:09:59 UTC 738513AC-9326-42DE-B4E2-DA51F6462943 iOS;18.1 ZoneFetch EphemeralGroup { "time":"06/11/2024, 9:09:59 UTC" "database":"PRIVATE" "zone":"com.apple.coredata.cloudkit.zone" "userId":"_0d9445f850459ec351330ca0fde4134f" "operationId":"611BA98C9B10D3F2" "operationGroupName":"EphemeralGroup" "operationType":"ZoneFetch" "platform":"iPhone" "clientOS":"iOS;18.1" "overallStatus":"USER_ERROR" "error":"ZONE_NOT_FOUND" "requestId":"738513AC-9326-42DE-B4E2-DA51F6462943" "executionTimeMs":"53" "interfaceType":"NATIVE" } Any pointers are greatly appreciated! Bastiaan

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..

I've developed an app that contains an inbox that displays message from a CloudKit container. Works perfectly on simulator. Once I tried to run it on a phone..in Xcode debug environment and TestFlight it is unable to complete any transactions with production database. I'm running out of ideas. So far I have tried: Verify settings between debug and release in Signing & Capabilities Add CloudKit.framework to Framework, Libraries, and Embedded Content Verify record and key names verify .entitlements files Please help!

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

Re SwiftData: is my understanding correct : generally speaking and by default insert method inserts objects into the context and context automatically persist - e.g. inserts them into container while the delete method does not - it only deletes from context and context does not delete them from the container unless save is called ? It is not clear from the documentation nor from the definitions : public func delete<T>(model: T.Type, where predicate: Predicate<T>? = nil, includeSubclasses: Bool = true) throws where T : PersistentModel //How can I test it ? I’m keen to learn where I can confirm this in Apple’s documentation or official articles, code definitions, apart from experimenting or consulting third-party materials. Where does it explicitly state that SwiftData includes an automatic saving feature but does not offer automatic deletion? "Meet SwiftData" (WWDC23): Around the 14:30 mark, Apple mentions that SwiftData automatically saves changes "at opportune moments." But nothing is advised re deleting ? Are we supposed to be taking hints : "Build an app with SwiftData" (WWDC23): This session demonstrates using context.save() to persist changes after deleting an object, implies the idea that deletion isn't automatic How to truly learn if you do not have official materials ? This is exact Science, not archeology or history. I feel like a speleologist.

I'm using Xcode 16 and SwiftUI targeting iOS 18. I'm new to Core Data, and when I create a new project and select to use Core Data as storage, I get boilerplate code for it. The problem is that when I try to see the preview without any change to the code, I get a Fatal Error: CrashReportError: Fatal Error in Persistence.swift Test crashed due to fatalError in Persistence.swift at line 52. Unresolved error Error Domain=NSSQLiteErrorDomain Code=8 "(null)" UserInfo={NSFilePath=/Users/monni/Library/Developer/Xcode/UserData/Previews/Simulator Devices/D0D98B5B-7E6F-4DC3-B16A-34D6D2958558/data/Containers/Data/Application/A98879A6-46F5-4E29-B2D7-AD294F1EFFD0/Library/Application Support/Test.sqlite, NSSQLiteErrorDomain=8}, ["NSSQLiteErrorDomain": 8, "NSFilePath": /Users/monni/Library/Developer/Xcode/UserData/Previews/Simulator Devices/D0D98B5B-7E6F-4DC3-B16A-34D6D2958558/data/Containers/Data/Application/A98879A6-46F5-4E29-B2D7-AD294F1EFFD0/Library/Application Support/Test.sqlite] When I try to open the SQLite database there are no entities in it. I have also tried xcrun simctl --set previews delete all, but with no luck.

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

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 } }

So I’m trying to setup an existing app to work with iCloud syncing. The syncing part seems to be working for the most part. When the app is first installed it sets up some data locally. Throughout the life of the app additional data is added through updates. There is a user default setup that stores the current data version, then compares it with the new version. If it’s newer, then loads the additional data. The issue I’ve got is a user can delete the app and reinstall, or install on another device which has that data version as 0, prompting another import even though the data in the cloud is current version, resulting in duplicate data once the sync is done. How can I persist that version data? I’ve seen NSUbiquitousKeyValueStore which seems to be a cloud based version of user defaults, but it says not to rely on it if it’s critical to app functions

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.

I'm facing a weird issue with SwiftData. I want to have one database that's local to the device and one that syncs to iCloud. In this example, LTRLink should be synced via iCloud while LTRMetadata should stay on-device only. I've it configured like the following: let schema = Schema([LTRLink.self, LTRMetadata.self]) let cloudkitConfiguration = ModelConfiguration("Remote", schema: schema, url: FileManager.remoteDatabaseFolderURL.appending(path: "Remote.sqlite"), cloudKitDatabase: .private("iCloud.com.xavimoll.abyss3")) let localConfiguration = ModelConfiguration("Local", schema: schema, url: FileManager.localDatabaseFolderURL.appending(path: "Local.sqlite"), cloudKitDatabase: .none) return try ModelContainer(for: schema, configurations: [cloudkitConfiguration, localConfiguration]) For some reason, when I create the iCloud schema, both models end up appearing as records on iCloud. I create the schema like this: let schema = Schema([LTRLink.self, LTRMetadata.self]) let cloudkitConfiguration = ModelConfiguration("Remote", schema: schema, url: FileManager.remoteDatabaseFolderURL.appending(path: "Remote.sqlite"), cloudKitDatabase: .private("iCloud.com.xavimoll.abyss3")) #if DEBUG // Needed to create the schema on iCloud try autoreleasepool { let desc = NSPersistentStoreDescription(url: cloudkitConfiguration.url) let opts = NSPersistentCloudKitContainerOptions(containerIdentifier: cloudkitConfiguration.cloudKitContainerIdentifier!) desc.cloudKitContainerOptions = opts desc.shouldAddStoreAsynchronously = false if let mom = NSManagedObjectModel.makeManagedObjectModel(for: [LTRLink.self]) { let container = NSPersistentCloudKitContainer(name: "Remote", managedObjectModel: mom) container.persistentStoreDescriptions = [desc] container.loadPersistentStores {_, err in if let err { fatalError(err.localizedDescription) } } try container.initializeCloudKitSchema() if let store = container.persistentStoreCoordinator.persistentStores.first { try container.persistentStoreCoordinator.remove(store) } } } #endif let localConfiguration = ModelConfiguration("Local", schema: schema, url: FileManager.localDatabaseFolderURL.appending(path: "Local.sqlite"), cloudKitDatabase: .none) return try ModelContainer(for: schema, configurations: [cloudkitConfiguration, localConfiguration]) The logic to initialize the CloudKit schema follows the documentation found here: https://developer.apple.com/documentation/swiftdata/syncing-model-data-across-a-persons-devices#Initialize-the-CloudKit-development-schema It looks like setting cloudKitDatabase: .none on the init for the ModelConfiguration doesn't do anything, and ends up being synced with iCloud either way. When I go to the iCloud console, I see the following: Does anyone know if there's any workaround that would allow me to have two databases where only one of them syncs to iCloud when using SwiftData?

The SwiftUI templates provided by Xcode typically create an in-memory store for preview purposes. I started from one of these templates and added the necessary code for working with CloudKit shares, but now the existing preview store creation gets runtime errors I'm struggling to understand. The ultimate error is: FAULT: NSInternalInconsistencyException: Unsupported feature in this configuration; { store = "<NSSQLCore: 0x12e26b170> (URL: file:///dev/null)"; } There are other things in the log like: warning: Multiple NSEntityDescriptions claim the NSManagedObject subclass 'Trip' so +entity is unable to disambiguate. This might be due in part to the normal full stack being instantiated during a unit test, but that was the only way I could step through the code to try to see what was causing the SwiftUI preview to crash. I can't build the full core data stack as normal, because then the unit tests and previews pollute the real store.

When you share records, they get put into a new zone. Creating a zone for the share makes sense to me, but I thought I read that there was a limit to the number of zones one could have (something like 1024). Does this mean a user can’t share more than 1024 separate items with 1024 different people? I assume any other items shared with the same group end up in an existing zone.

I'm trying to look at what the best way to do thumbnails for images that are saved in core data, which are being synced across multiple devices. I know I can save a lower quality version into core data, but I'm wondering if there's a better way of doing it. I've come across quick look thumbnailing which looks like what I want, but I'm not sure if it can be adapted for core data as its using file paths, whereas the images are stored in a data type property in core data. From what I can tell, I'd have to save the image locally, produce the thumbnail, then delete the local image

Hello, SwiftData is not working correctly with Swift Concurrency. And it’s sad after all this time. I personally found a regression. The attached code works perfectly fine on iOS 17.5 but doesn’t work correctly on iOS 18 or iOS 18.1. A model can be updated from the background (Task, Task.detached or ModelActor) and refreshes the UI, but as soon as the same item is updated from the View (fetched via a Query), the next background updates are not reflected anymore in the UI, the UI is not refreshed, the updates are not merged into the main. How to reproduce: Launch the app Tap the plus button in the navigation bar to create a new item Tap on the “Update from Task”, “Update from Detached Task”, “Update from ModelActor” many times Notice the time is updated Tap on the “Update from View” (once or many times) Notice the time is updated Tap again on “Update from Task”, “Update from Detached Task”, “Update from ModelActor” many times Notice that the time is not update anymore Am I doing something wrong? Or is this a bug in iOS 18/18.1? Many other posts talk about issues where updates from background thread are not merged into the main thread. I don’t know if they all are related but it would be nice to have 1/ bug fixed, meaning that if I update an item from a background, it’s reflected in the UI, and 2/ proper documentation on how to use SwiftData with Swift Concurrency (ModelActor). I don’t know if what I’m doing in my buttons is correct or not. Thanks, Axel import SwiftData import SwiftUI @main struct FB_SwiftData_BackgroundApp: App { var body: some Scene { WindowGroup { ContentView() .modelContainer(for: Item.self) } } } struct ContentView: View { @Environment(\.modelContext) private var modelContext @State private var simpleModelActor: SimpleModelActor! @Query private var items: [Item] var body: some View { NavigationView { VStack { if let firstItem: Item = items.first { Text(firstItem.timestamp, format: Date.FormatStyle(date: .omitted, time: .standard)) .font(.largeTitle) .fontWeight(.heavy) Button("Update from Task") { let modelContainer: ModelContainer = modelContext.container let itemID: Item.ID = firstItem.persistentModelID Task { let context: ModelContext = ModelContext(modelContainer) guard let itemInContext: Item = context.model(for: itemID) as? Item else { return } itemInContext.timestamp = Date.now.addingTimeInterval(.random(in: 0...2000)) try context.save() } } .buttonStyle(.bordered) Button("Update from Detached Task") { let container: ModelContainer = modelContext.container let itemID: Item.ID = firstItem.persistentModelID Task.detached { let context: ModelContext = ModelContext(container) guard let itemInContext: Item = context.model(for: itemID) as? Item else { return } itemInContext.timestamp = Date.now.addingTimeInterval(.random(in: 0...2000)) try context.save() } } .buttonStyle(.bordered) Button("Update from ModelActor") { let container: ModelContainer = modelContext.container let persistentModelID: Item.ID = firstItem.persistentModelID Task.detached { let actor: SimpleModelActor = SimpleModelActor(modelContainer: container) await actor.updateItem(identifier: persistentModelID) } } .buttonStyle(.bordered) Button("Update from ModelActor in State") { let container: ModelContainer = modelContext.container let persistentModelID: Item.ID = firstItem.persistentModelID Task.detached { let actor: SimpleModelActor = SimpleModelActor(modelContainer: container) await MainActor.run { simpleModelActor = actor } await actor.updateItem(identifier: persistentModelID) } } .buttonStyle(.bordered) Divider() .padding(.vertical) Button("Update from View") { firstItem.timestamp = Date.now.addingTimeInterval(.random(in: 0...2000)) } .buttonStyle(.bordered) } else { ContentUnavailableView( "No Data", systemImage: "slash.circle", // 􀕧 description: Text("Tap the plus button in the toolbar") ) } } .toolbar { ToolbarItem(placement: .primaryAction) { Button(action: addItem) { Label("Add Item", systemImage: "plus") } } } } } private func addItem() { modelContext.insert(Item(timestamp: Date.now)) try? modelContext.save() } } @ModelActor final actor SimpleModelActor { var context: String = "" func updateItem(identifier: Item.ID) { guard let item = self[identifier, as: Item.self] else { return } item.timestamp = Date.now.addingTimeInterval(.random(in: 0...2000)) try! modelContext.save() } } @Model final class Item: Identifiable { var timestamp: Date init(timestamp: Date) { self.timestamp = timestamp } }

The WWDC2024 custom data store example doesn't provide any details on how one would go about creating a DataStoreSnapshot. The example uses a DefaultSnapshot for persisting the data in the DefaultSnapshot format directly in the JSON file. There appears to be no documentation or examples of how one might create a DataStoreSnapshot from data from another database. The Apple documentation for DefaultSnapshot provides no examples of how one might create such a snapshot from data retrieved elsewhere. Can anyone provide a simple example of how one might create such a snapshot from a remote database such that it can be returned as part of the response to a fetch request. For the purpose of this example let's assume I have a CSV file with rows of data and code to read the data from this file. How would I create a snapshot or snapshots for each of the rows of data.

My app is able to receive data updates when it is in foreground. however, when i move it in background then sync engine stops syncing until I again move app to foreground.