I've got an application built on top of SwiftData (+ CloudKit) which is published to App Store. I've got a problem where on each app update, the data saved in the database is duplicated to the end user. Obviously this isn't wanted behaviour, and I'm really looking forward to fixing it. However, given the restrictions of SwiftData, I haven't found a single fix for this. The data duplication happens automatically on the first initial sync after the update. My guess is that it's because it doesn't detect the data already in the device, so it pulls all data from iCloud and appends it to the database where data in reality exists.

I'm using SwiftData with an @Model and am also using an @ModelActor. I've fixed all concurrency issues and have migrated to Swift 6. I am getting a console error that I do not understand how to clear. I get this error in Swift 6 and Swift 5. I do not experience any issue with the app. It seems to be working well. But I want to try to get all issues taken care of. I am using the latest Xcode beta. error: the replacement path doesn't exist: "/var/folders/1q/6jw9d6mn0gx1znh1n19z2v9r0000gp/T/swift-generated-sources/@_swiftmacro_17MyAppName14MyModelC4type18_PersistedPr> opertyfMa.swift"

I am trying to port my application over to CloudKit. My app worked fine before, but then I made scheme of changes and am trying to deploy to a new container. For some reason, the database is not being created after I create the container through Xcode. I think I have configured the app correctly and a container was created, but no records were deployed. My app current stores data locally on individual devices just fine but they don't sync with each other. That's why I would like to use CloudKit. See screenshot from Xcode of where I have configured the container. I also have background notifications enabled. Also see screenshot from console where the container has been created, but no records have been. Any suggestions would be greatly appreciated. Thank you

I've been trying to setup a successful migration, but it keeps failing with this error: NSCloudKitMirroringDelegate are not reusable and should have a lifecycle tied to a given instance of NSPersistentStore. I can't find any information about this online. I added breakpoints throughout the code in willMigrate, and it originally failed on this line: try? context.save() I removed that, and it still failed. After I reload the app, it doesn't run the migration again and the app loads successfully. I figured since it crashed, it would keep trying, but I guess not. Here's how my migration is setup. enum MigrationV1ToV2: SchemaMigrationPlan { static var schemas: [any VersionedSchema.Type] { [SchemaV1.self, SchemaV2.self] } static var stages: [MigrationStage] { [stage] } static let stage = MigrationStage.custom( fromVersion: SchemaV1.self, toVersion: SchemaV2.self, willMigrate: { context in // Get cycles let cycles = try? context.fetch(FetchDescriptor<SchemaV1.Cycle>()) if let cycles { for cycle in cycles { // Create new recurring objects based on what's in the cycle for income in cycle.income { let recurring = SchemaV2.Recurring(name: income.name, frequency: income.frequency, kind: .income) recurring.addAmount(.init(date: cycle.startDate, amount: income.amount)) context.insert(recurring) } for expense in cycle.expenses { let recurring = SchemaV2.Recurring(name: expense.name, frequency: expense.frequency, kind: .expense) recurring.addAmount(.init(date: cycle.startDate, amount: expense.amount)) context.insert(recurring) } for savings in cycle.savings { let recurring = SchemaV2.Recurring(name: savings.name, frequency: savings.frequency, kind: .savings) recurring.addAmount(.init(date: cycle.startDate, amount: savings.amount)) context.insert(recurring) } for investment in cycle.investments { let recurring = SchemaV2.Recurring(name: investment.name, frequency: investment.frequency, kind: .investment) recurring.addAmount(.init(date: cycle.startDate, amount: investment.amount)) context.insert(recurring) } } //try? context.save() } else { print("The cycles were not able to be fetched.") } }, didMigrate: { context in // Get new recurring objects let newRecurring = try? context.fetch(FetchDescriptor<SchemaV2.Recurring>()) if let newRecurring { for recurring in newRecurring { // Get all recurring with the same name and kind let sameName = newRecurring.filter({ $0.name == recurring.name && $0.kind == recurring.kind }) // Add amount history to recurring object, and then remove matching for match in sameName { recurring.amountHistory.append(contentsOf: match.amountHistory) context.delete(match) } } //try? context.save() } else { print("The new recurring objects could not be fetched.") } } ) } Here's is my modelContainer in the app file. There is a fatal error occurring here that's crashing the app. var sharedModelContainer: ModelContainer = { let schema = Schema(versionedSchema: SchemaV2.self) let modelConfiguration = ModelConfiguration(schema: schema, isStoredInMemoryOnly: false) do { return try ModelContainer( for: schema, migrationPlan: MigrationV1ToV2.self, configurations: [modelConfiguration] ) } catch { fatalError("Could not create ModelContainer: \(error)") } }() Does anyone have any suggestions for this? EDIT: I found this error in the console that may be relevant. BUG IN CLIENT OF CLOUDKIT: Registering a handler for a CKScheduler activity identifier that has already been registered (com.apple.coredata.cloudkit.activity.export.8F7A1261-4324-40B4-B041-886DF36FBF0A). CloudKit setup failed because it couldn't register a handler for the export activity. There is another instance of this persistent store actively syncing with CloudKit in this process. And here is the fatal error Fatal error: Could not create ModelContainer: SwiftDataError(_error: SwiftData.SwiftDataError._Error.loadIssueModelContainer, _explanation: nil)

I am having problems when I first loads the app. The time it takes for the Items to be sync from my CloudKit to my local CoreData is too long. Code I have the model below defined by my CoreData. public extension Item { @nonobjc class func fetchRequest() -> NSFetchRequest<Item> { NSFetchRequest<Item>(entityName: "Item") } @NSManaged var createdAt: Date? @NSManaged var id: UUID? @NSManaged var image: Data? @NSManaged var usdz: Data? @NSManaged var characteristics: NSSet? @NSManaged var parent: SomeParent? } image and usdz columns are both marked as BinaryData and Attribute Allows External Storage is also selected. I made a Few tests loading the data when the app is downloaded for the first time. I am loading on my view using the below code: @FetchRequest( sortDescriptors: [NSSortDescriptor(keyPath: \Item.createdAt, ascending: true)] ) private var items: FetchedResults<Item> var body: some View { VStack { ScrollView(.vertical, showsIndicators: false) { LazyVGrid(columns: columns, spacing: 40) { ForEach(items, id: \.self) { item in Text(item.id) } } } } } Test 1 - Just loads everything When I have on my cloudKit images and usdz a total of 100mb data, it takes around 140 seconds to show some data on my view (Not all items were sync, that takes much longer time) Test 2 - Trying getting only 10 items at the time () This takes the same amount of times the long one . I have added the following in my class, and removed the @FetchRequest: @State private var items: [Item] = [] // CK @State private var isLoading = false @MainActor func loadMoreData() { guard !isLoading else { return } isLoading = true let fetchRequest = NSFetchRequest<Item>(entityName: "Item") fetchRequest.predicate = NSPredicate(format: "title != nil AND title != ''") fetchRequest.fetchLimit = 10 fetchRequest.fetchOffset = items.count fetchRequest.predicate = getPredicate() fetchRequest.sortDescriptors = [NSSortDescriptor(keyPath: \Item.createdAt, ascending: true)] do { let newItems = try viewContext.fetch(fetchRequest) DispatchQueue.main.async { items.append(contentsOf: newItems) isLoading = false } } catch {} } Test 2 - Remove all images and usdz from CloudKit set all as Null Setting all items BinaryData to null, it takes around 8 seconds to Show the list. So as we can see here, all the solutions that I found are bad. I just wanna go to my CloudKit and fetch the data with my CoreData. And if possible to NOT fetch all the data because that would be not possible (imagine the future with 10 or 20GB or data) What is the solution for this loading problem? What do I need to do/fix in order to load lets say 10 items first, then later on the other items and let the user have a seamlessly experience? Questions What are the solutions I have when the user first loads the app? How to force CoreData to query directly cloudKit? Does CoreData + CloudKit + NSPersistentCloudKitContainer will download the whole CloudKit database in my local, is that good???? Storing images as BinaryData with Allow external Storage does not seems to be working well, because it is downloading the image even without the need for the image right now, how should I store the Binary data or Images in this case?

Hi, I have designed an app which needs to reschedule notifications according to the user's calendar at midnight. The function has been implemented successfully via backgroundtask. But since the app has enabled iCloud sync, some users will edit their calendar on their iPad and expect that the notifications will be sent promptly to them on iPhone without launching the app on their iPhone. But the problem is that if they haven't launched the app on their iPhone, iCloud sync won't happen. The notifications on their iPhone haven't been updated and will be sent wrongly. How can I design some codes to let iCloud sync across the devices without launching the app at midnight and then reschedule notifications?

Hello, When attempting to create a CKShare on a personal device linked to a Family iCloud plan (non-primary account holder), the operation fails with a quotaExceeded error. This occurs with the Family plan having 1.5TB available storage space. This is also causing a data loss for the object(s) that were attempted to be shared. Details Account Type: Family iCloud Plan (2TB total storage) Current Family Usage: 399GB iCloud Account Usage: 70 GB Steps to Reproduce: Have an iCloud account with storage over the 5GB free space limit. Be on a part of a iCloud Family Plan as the non-primary account holder. Have storage space available in the Family Plan Attempt to start a CloudKit Share/Collaboration on the device. Observe that the CKShare creation fails with a quotaExceeded error. Expected Behavior: The CKShare should be successfully created, reflecting the total available storage of the Family plan. Observed Behavior: The CKShare fails to be created with quotaExceeded. Additional Testing On a test device using an iCloud account with no stored data, the CKShare was created successfully and shared without issue. Suspected Cause The CKShare functionality is verifying the personal storage allocation of the iCloud account and failing without checking total available storage provided by the Family plan.

I've already submitted this as a bug report to Apple, but I am posting here so others can save themselves some troubleshooting. This is submitted as FB14337982 with an attached complete Xcode project to replicate. In iOS 17 we use a ModelActor to download data which is saved as an Event, and then save it to SwiftData with a relationship to a Location. In iOS 18 22A5307d we are seeing that this code no longer persists the relationship to the Location, but still saves the Event. If we put a breakpoint in that ModelActor we see that the object graph is correct within the ModelActor stack trace at the time we call modelContext.save(). However, after saving, the relationship is missing from the default.store SQLite file, and of course from the app UI. Here is a toy example showing how inserting an Employee into a Company using a ModelActor gives unexpected results in iOS 18 22A5307d but works as expected in iOS 17. It appears that no relationships data survives being saved in a ModelActor.ModelContext. Also note there seems to be a return of the old bug that saving this data in the ModelActor does not update the @Query in the UI in iOS 18 but does so in iOS 17. Models @Model final class Employee { var uuid: UUID = UUID() @Relationship(deleteRule: .nullify) public var company: Company? /// For a concise display @Transient var name: String { self.uuid.uuidString.components(separatedBy: "-").first ?? "NIL" } init(company: Company?) { self.company = company } } @Model final class Company { var uuid: UUID = UUID() @Relationship(deleteRule: .cascade, inverse: \Employee.company) public var employees: [Employee]? = [] /// For a concise display @Transient var name: String { self.uuid.uuidString.components(separatedBy: "-").first ?? "NIL" } init() { } } ModelActor import OSLog private let logger = Logger(subsystem: Bundle.main.bundleIdentifier!, category: "SimpleModelActor") @ModelActor final actor SimpleModelActor { func addEmployeeTo(CompanyWithID companyID: PersistentIdentifier?) { guard let companyID, let company: Company = self[companyID, as: Company.self] else { logger.error("Could not get a company") return } let newEmployee = Employee(company: company) modelContext.insert(newEmployee) logger.notice("Created employee \(newEmployee.name) in Company \(newEmployee.company?.name ?? "NIL")") try! modelContext.save() } } ContentView import OSLog private let logger = Logger(subsystem: Bundle.main.bundleIdentifier!, category: "View") struct ContentView: View { @Environment(\.modelContext) private var modelContext @Query private var companies: [Company] @Query private var employees: [Employee] @State private var simpleModelActor: SimpleModelActor! var body: some View { ScrollView { LazyVStack { DisclosureGroup("Instructions") { Text(""" Instructions: 1. In iOS 17, tap Add in View. Observe that an employee is added with Company matching the shown company name. 2. In iOS 18 beta (22A5307d), tap Add in ModelActor. Note that the View does not update (bug 1). Note in the XCode console that an Employee was created with a relationship to a Company. 3. Open the default.store SQLite file and observe that the created Employee does not have a Company relationship (bug 2). The relationship was not saved. 4. Tap Add in View. The same code is now executed in a Button closure. Note in the XCode console again that an Employee was created with a relationship to a Company. The View now updates showing both the previously created Employee with NIL company, and the View-created employee with the expected company. """) .font(.footnote) } .padding() Section("**Companies**") { ForEach(companies) { company in Text(company.name) } } .padding(.bottom) Section("**Employees**") { ForEach(employees) { employee in Text("Employee \(employee.name) in company \(employee.company?.name ?? "NIL")") } } Button("Add in View") { let newEmployee = Employee(company: companies.first) modelContext.insert(newEmployee) logger.notice("Created employee \(newEmployee.name) in Company \(newEmployee.company?.name ?? "NIL")") try! modelContext.save() } .buttonStyle(.bordered) Button("Add in ModelActor") { Task { await simpleModelActor.addEmployeeTo(CompanyWithID: companies.first?.persistentModelID) } } .buttonStyle(.bordered) } } .onAppear { simpleModelActor = SimpleModelActor(modelContainer: modelContext.container) if companies.isEmpty { let newCompany = Company() modelContext.insert(newCompany) try! modelContext.save() } } } }

I have a SwiftData model where I need to customize behavior based on the value of a property (connectorType). Here’s a simplified version of my model: @Model public final class ConnectorModel { public var connectorType: String ... func doSomethingDifferentForEveryConnectorType() { ... } } I’d like to implement doSomethingDifferentForEveryConnectorType in a way that allows the behavior to vary depending on connectorType, and I want to follow best practices for scalability and maintainability. I’ve come up with three potential solutions, each with pros and cons, and I’d love to hear your thoughts on which one makes the most sense or if there’s a better approach: **Option 1: Use switch Statements ** func doSomethingDifferentForEveryConnectorType() { switch connectorType { case "HTTP": // HTTP-specific logic case "WebSocket": // WebSocket-specific logic default: // Fallback logic } } Pros: Simple to implement and keeps the SwiftData model observable by SwiftUI without any additional wrapping. Cons: If more behaviors or methods are added, the code could become messy and harder to maintain. **Option 2: Use a Wrapper with Inheritance around swiftdata model ** @Observable class ParentConnector { var connectorModel: ConnectorModel init(connectorModel: ConnectorModel) { self.connectorModel = connectorModel } func doSomethingDifferentForEveryConnectorType() { fatalError("Not implemented") } } @Observable class HTTPConnector: ParentConnector { override func doSomethingDifferentForEveryConnectorType() { // HTTP-specific logic } } Pros: Logic for each connector type is cleanly organized in subclasses, making it easy to extend and maintain. Cons: Requires introducing additional observable classes, which could add unnecessary complexity. **Option 3: Use a @Transient class that customizes behavior ** protocol ConnectorProtocol { func doSomethingDifferentForEveryConnectorType(connectorModel: ConnectorModel) } class HTTPConnectorImplementation: ConnectorProtocol { func doSomethingDifferentForEveryConnectorType(connectorModel: ConnectorModel) { // HTTP-specific logic } } Then add this to the model: @Model public final class ConnectorModel { public var connectorType: String @Transient public var connectorImplementation: ConnectorProtocol? // Or alternatively from swiftui I could call myModel.connectorImplementation.doSomethingDifferentForEveryConnectorType() to avoid this wrapper func doSomethingDifferentForEveryConnectorType() { connectorImplementation?.doSomethingDifferentForEveryConnectorType(connectorModel: self) } } Pros: Decouples model logic from connector-specific behavior. Avoids creating additional observable classes and allows for easy extension. Cons: Requires explicitly passing the model to the protocol implementation, and setup for determining the correct implementation needs to be handled elsewhere. My Questions Which approach aligns best with SwiftData and SwiftUI best practices, especially for scalable and maintainable apps? Are there better alternatives that I haven’t considered? If Option 3 (protocol with dependency injection) is preferred, what’s the best way to a)manage the transient property 2) set the correct implementation and 3) pass reference to swiftdata model? Thanks in advance for your advice!

I have been trying to get this to work since it was announced a few years ago but with no joy. I'm struggling to get Apple's example code to behave itself too. Seems overly complex and buggy. So I set out to create a simplified version myself. I have got the database to sync with CloudKit and I can see my records in the developer dashboard. I'm trying to use container.record(for: object.objectID) to get the CKRecord for it, but this always fails. The next step would be to add the participant. I try to add the participant based on this code: Button { let record = fetchRecord(for: items[0]) //hack just to use the first record for dev testing let share = CKShare(rootRecord: record) let persistenceController = PersistenceController.shared persistenceController.addParticipant( emailAddress: "andrew@ambrit.com", permission: .readWrite, share: share) { share, error in if let error = error { print("Error: \(error.localizedDescription)") } else if let share = share { print("Share updated successfully: \(share)") } } } label: { Label("Participants", systemImage: "person") } and extension PersistenceController { func addParticipant(emailAddress: String, permission: CKShare.ParticipantPermission = .readWrite, share: CKShare, completionHandler: ((_ share: CKShare?, _ error: Error?) -> Void)?) { let container = PersistenceController.shared.container let lookupInfo = CKUserIdentity.LookupInfo(emailAddress: emailAddress) let persistentStore = privatePersistentStore //share.persistentStore! container.fetchParticipants(matching: [lookupInfo], into: persistentStore) { (results, error) in guard let participants = results, let participant = participants.first, error == nil else { completionHandler?(share, error) return } participant.permission = permission participant.role = .privateUser share.addParticipant(participant) container.persistUpdatedShare(share, in: persistentStore) { (share, error) in if let error = error { print("\(#function): Failed to persist updated share: \(error)") } completionHandler?(share, error) } } } } My immediate problem is that when I call fetchRecord it doesn't find anything despite the record being available in the CloudKit dashboard. func fetchRecord(for object: NSManagedObject) -> CKRecord { let container = PersistenceController.shared.container print ("Fetching record \(object.objectID)") if let record = container.record(for: object.objectID) { print("CKRecord ID: \(record.recordID)") print("Record Name: \(record.recordID.recordName)") return record } else { fatalError("Record not found") } }

I have a simple model that contains a one-to-many relationship to itself to represent a simple tree structure. It is set to cascade deletes so deleting the parent node deletes the children. Unfortunately I get an error when I try to batch delete. A test demonstrates: @Model final class TreeNode { var parent: TreeNode? @Relationship(deleteRule: .cascade, inverse: \TreeNode.parent) var children: [TreeNode] = [] init(parent: TreeNode? = nil) { self.parent = parent } } func testBatchDelete() throws { let config = ModelConfiguration(isStoredInMemoryOnly: true) let container = try ModelContainer(for: TreeNode.self, configurations: config) let context = ModelContext(container) context.autosaveEnabled = false let root = TreeNode() context.insert(root) for _ in 0..<10 { let child = TreeNode(parent: root) context.insert(child) } try context.save() // fails if first item doesn't have a nil parent, succeeds otherwise // which row is first is random, so will succeed sometimes try context.delete(model: TreeNode.self) } The error raised is: CoreData: error: Unhandled opt lock error from executeBatchDeleteRequest Constraint trigger violation: Batch delete failed due to mandatory OTO nullify inverse on TreeNode/parent and userInfo { NSExceptionOmitCallstacks = 1; NSLocalizedFailureReason = "Constraint trigger violation: Batch delete failed due to mandatory OTO nullify inverse on TreeNode/parent"; "_NSCoreDataOptimisticLockingFailureConflictsKey" = ( ); } Interestingly, if the first record when doing an unsorted query happens to be the parent node, it works correctly, so the above unit test will actually work sometimes. Now, this can be "solved" by changing the reverse relationship to an optional like so: @Relationship(deleteRule: .cascade, inverse: \TreeNode.parent) var children: [TreeNode]? The above delete will work fine. However, this causes issues with predicates that test counts in children, like for instance deleting only nodes where children is empty for example: try context.delete(model: TreeNode.self, where: #Predicate { $0.children?.isEmpty ?? true }) It ends up crashing and dumps a stacktrace to the console with: An uncaught exception was raised Keypath containing KVC aggregate where there shouldn't be one; failed to handle children.@count (the stacktrace is quite long and deep in CoreData's NSSQLGenerator) Does anyone know how to work around this?

I have encountered an issue with a customer’s data access after they migrated to a different iCloud account, and I’m looking for guidance. The Situation: The customer was logged into their account on my app, which was associated with a specific iCloud account (iCloud A). They had all their app data available while using iCloud A. The customer then switched to a new iCloud account (iCloud B) on the same device, while still using the same app account. After switching iCloud accounts, their data is no longer visible in the app or my CloudKit dashboard. My Investigation: I accessed the customer’s CloudKit data via the CloudKit Console, acting as their iCloud account. I couldn’t find the private database zone or any of their records when accessing iCloud A through the console. I don’t believe the data was deleted since actions performed under iCloud B shouldn’t affect data stored in iCloud A. My Hypothesis: I suspect that the customer’s old iCloud account (iCloud A) may have downgraded or stopped paying for iCloud storage. If the iCloud subscription is inactive or expired, could that prevent me from accessing their CloudKit data? Would renewing the iCloud subscription for iCloud A restore access to the missing data? Questions: Does an unpaid or expired iCloud account restrict access to CloudKit records, even if they weren’t deleted? Would paying for iCloud storage again restore the data previously stored in CloudKit? Is there any way to recover the customer’s CloudKit data if they are unable to access their old iCloud account? If anyone has a simpler approach to recovering the customer’s iCloud-stored app data or has experience dealing with iCloud migrations like this, I’d appreciate your insights. Thank you in advance for any advice!

In Apple Numbers and similar apps, a user can save a document to iCloud Drive, and collaborate with other users. From what I can gather, it seems to use two mechanisms: the document as a whole is synced via iCloud Drive, but when a collaboration is started, it seems to use CloudKit records to do live updates. I am working on a similar app, that saves documents to iCloud Drive (on Mac, iPad, and iPhone). Currently it only syncs via iCloud Drive, re-reading the entire (often large) document when a remote change occurs. This can lead to a delay of several seconds (up to a minute) for the document to be saved, synced to the server, synced from the server, and re-read. I'm working on adding a "live sync", i.e. the ability to see changes in as near to real-time as feasible, like in Apple's apps. The document as a whole will remain syncing via iCloud Drive. My thought is to add a CloudKit CKRecord-based sync when two or more users are collaborating on a document, recording only the diffs for quick updates. The app would no longer re-read the entire document when iCloud Drive updates it while in use, and would instead read the CloudKit records and apply those changes. This should be much faster. Is my understanding of how Apple does it correct? Does my proposed approach seem sensible? Has anyone else implemented something like this, with iCloud Drive-based documents and a CloudKit live sync? In terms of technologies, I see that Apple now has a Shared with You framework, with the ability to use a NSItemProvider to start the collaboration. Which raises the question, should I use the iCloud Drive document for the collaboration (as I do now), or the CloudKit CKShare diff? I think I'd have to use the document as a whole, both so it works with the Send Copy option, and so a user that doesn't have the document gets it when using Collaborate. Once the collaboration is underway, I'd want to start the CloudKit channel. So I guess I'd save the CKShare to the server, get its URL, and save that in the document, so another user can read that URL as part of their initial load of the document from iCloud Drive? Once two (or more) users have the document via iCloud Drive, and the CKShare via the embedded URL, I should be able to do further live-sync updates via CloudKit. If a user closes the document and re-opens it, they'd get the updates via iCloud Drive, so no need to apply any updates from before the document was opened. Does all this sound reasonable, or am I overlooking some gotcha? I'd appreciate any advice from people who have experience with this kind of syncing.

Something I want to know and all users of CKSyncEngine care about I'm going to build a full stack solution using CKSyncEngine, but what's the near future and the support and maintenance priorities inside Apple for CKSyncEngine? There is only one short video for CKSyncEngine, in 2023, no updates after that, no future plans mentioned. I'm worried that this technology be deprecated or not activity maintained. This is a complex technology, without being activity maintained (or open-sourced) there will be fatal production issues we the developer cannot solve. The CK developer in the video stated that "many apps" were using the framework, but he did not list any. The only named is NSUbiquitousKeyValueStore, but NSUbiquitousKeyValueStore is too simple a use case. I wonder is apple's Notes.app using it, or going to use it? Is SwiftData using it? API Problems The API design seems a little bit tricky, not designed from a user's perspective. handleEvent doesn't contain any context information about which batch. How do I react the event properly? Let's say our sync code and CKSyncEngine, and callbacks are all on a dedicated thread. Consider this: in nextRecordZoneChangeBatch you provided a batch of changes, let's call this BATCH 1, including an item in database with uuid "xxx" and name "yyy" before the changes are uploaded, there are new changes from many OTHER BACKGROUND THREADS made to the database. item "xxx"'s name is now "zzz" handle SentRecordZoneChanges event: I get records that uploaded or failed, but I don't know which BATCH the records belong to. How do I decide if i have to mark "xxx" as finished uploading or not? If I mark xxx as finished that's wrong, the new name "zzz" is not uploaded. I have to compare every field of xxx with the savedRecord to decide if I finished uploading or not? That is not acceptable as the performance and memory will be bad. Other questions I have to add recordIDs to state, and wait for the engine to react. I don't think this is a good idea, because recordID is a CloudKit concept, and what I want to sync is a local database. I don't see any rational for this, or not documented. If the engine is going to ask for a batch of records, you can get all record ids from the batch?

why not working?

Hi, I've been using Core Data + CloudKit via NSPersistentCloudKitContainer for several years now. Back then I just created my Core Data AND CloudKit fields by hand. Now the time has come for a little lightweight migration to a new Core Data model, let's say I just needed to add one String attribute. So I've done the Core Data local migration as usual, then added this to container code: try? persistentContainer.initializeCloudKitSchema(options: NSPersistentCloudKitContainerSchemaInitializationOptions()) Run. And everything worked great. but… Now I've noticed that CloudKit created new CKAsset fields for each String attribute that I had in Core Data (about 5 new CKAsset fields). Is this normal!? Why? ! Is it safe to deploy these changes to prod? ty. ChatGPT said: "This field is used internally by CloudKit to handle large string values. If the string value is small enough, it is stored in the normal String field, but if it exceeds the size limit (about 1KB), the string is automatically stored as a CKAsset."

In a CloudKit private database, the Owner creates a custom zone and performs the following actions: Creates CKRecord1 with CKShare1 and invites Participant1 to it. Creates CKRecord2 with CKShare2 and invites Participant2 to it. Creates CKRecordShared, which should be accessible to both Participant1 and Participant2. How can I achieve step 3? I observed that: Setting a regular reference from CKRecord1 (or CKRecord2) to CKRecordShared does not automatically make CKRecordShared accessible to Participant1 (or Participant2). CKRecordShared can only have one parent, so it cannot be directly linked via parent reference to both Participant1 and Participant2 at the same time. One potential solution I see is to have the Owner create a separate CKShare for CKRecordShared and share it explicitly with each participant. However, this approach could lead to user errors, as it requires careful management of multiple shares for each participant. Is there a better way to handle this scenario, ensuring that CKRecordShared is accessible to multiple participants without introducing unnecessary complexity or potential errors?

I am trying to read and write a text file from an App written in Swift in XCode directly to the "iCloud Drive" folder in Files on the iPhone. The app worked readlly reading and writing to the Documents folder in the App container, and then readily to the "On My iPhone" folder in Files after adding 2 lines to the plist that I found in a search online. But I have been unable to get to the iCloud Drive folder. I found an item called "Enabling Document Storage in iCloud Drive" in "iCloud Design Guide" with additional plist entries that states "These settings allow iCloud Drive to provide public access to the files stored in your app’s container": NSUbiquitousContainers iCloud.com.example.MyApp NSUbiquitousContainerIsDocumentScopePublic NSUbiquitousContainerSupportedFolderLevels Any NSUbiquitousContainerName MyApp I think I changed the MyApp items appropriately. I have enabled iCloud in my App and the XCode General, and Signing entries. But this does not work. There are no error messages and no "Steps" shown in the "Capabilities" entry in Xcode. A little help? :-)

My app has been in the App Store a few months. In that time I've added a few updates to my SwiftData schema using a MigrationPlan, and things were seemingly going ok. But then I decided to add CloudKit syncing. I needed to modify my models to be compatible. So, I added another migration stage for it, changed the properties as needed (making things optional or adding default values, etc.). In my tests, everything seemed to work smoothly updating from the previous version to the new version with CloudKit. So I released it to my users. But, that's when I started to see the crashes and error reports come in. I think I've narrowed it down to when users update from older versions of the app. I was finally able to reproduce this on my end, and Core Data is throwing an error when loading the ModelContainer saying "CloudKit integration requires that all attributes be optional, or have a default value set." Even though I did this in the latest schema. It’s like it’s trying to load CloudKit before performing the schema migration, and since it can’t, it just fails and won’t load anything. I’m kinda at a loss how to recover from this for these users other than tell them to delete their app and restart, but obviously they’ll lose their data that way. The only other idea I have is to setup some older builds on TestFlight and direct them to update to those first, then update to the newest production version and hope that solves it. Any other ideas? And what can I do to prevent this for future users who maybe reinstall the app from an older version too? There's nothing special about my code for loading the ModelContainer. Just a basic: let container = try ModelContainer( for: Foo.self, Bar.self, migrationPlan: SchemaMigration.self, configurations: ModelConfiguration(cloudKitDatabase: .automatic) )

Hey, For some reason I see crashes for my iOS app related to CloudKit entitlements. The crash happens on start up and it says: "CKException - Application has malformed entitlements. Found value "*" for entitlement com.apple.developer.icloud-services, expected an array of strings" I have checked my entitlements of the same build on App Store Connect and it shows "com.apple.developer.icloud-services: ( "CloudKit" )" So I am not sure why users are having this issue. I haven't been able to reproduce it. Does anyone have any idea why this is happening? Thanks