I have encountered an issue that when using a ModelActor to sync data in the background, the app will crash if one of the operations is to remove a PersistentModel from the context.
This is running on the latest beta of Xcode 16 with visionOS 1.2 as target and in Swift 6 language mode.
The code is being executed in a ModelActor.
The error is first thrown by:
#5 0x00000001c3223280 in PersistentModel.getValue<τ_0_0>(forKey:) ()
Thread 1: Fatal error: Context is missing for Optional(SwiftData.PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(url: x-coredata://97AA86BC-475D-4509-9004-D1182ABA1922/Reminder/p303), implementation: SwiftData.PersistentIdentifierImplementation))
func globalSync() async {
await fetchAndSyncFolders()
let result = await fetchReminders()
switch result {
case .success(let ekReminders):
var localReminders = (try? await fetch(FetchDescriptor<Reminder>())) ?? []
// Handle local reminders with nil ekReminderID by creating new EKReminders for them
for reminder in localReminders {
if reminder.ekReminderID == nil {
await self.createEkReminder(reminder: reminder)
}
}
// Re-fetch local reminders to include newly created EKReminderIDs
localReminders = (try? await fetch(FetchDescriptor<Reminder>())) ?? []
var localReminderDict = [String: Reminder]()
for reminder in localReminders {
if let ekReminderID = reminder.ekReminderID {
if let existingReminder = localReminderDict[ekReminderID] {
self.delete(model: existingReminder)
} else {
localReminderDict[ekReminderID] = reminder
}
}
}
let ekReminderDict = createReminderLookup(byID: ekReminders)
await self.syncReminders(localReminders: Array(localReminderDict.values), localReminderDict: localReminderDict, ekReminderDict: ekReminderDict)
// Merge duplicates
await self.mergeDuplicates(localReminders: localReminders)
save()
case .failure(let error):
print("Failed to fetch reminders: \(error.localizedDescription)")
}
}
iCloud & Data
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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"
Background
I have an established app in the App Store which has been using NSPersistentCloudkitContainer since iOS 13 without any issues.
I've been running my app normally on an iOS device running the iOS 15 betas, mainly to see problems arise before my users see them.
Ever since iOS 15 (beta 4) my app has failed to sync changes - no matter how small the change. An upload 'starts' but never completes. After a minute or so the app quits to the Home Screen and no useful information can be gleaned from crash reports. Until now I've had no idea what's going on.
Possible Bug in the API?
I've managed to replicate this behaviour on the simulator and on another device when building my app with Xcode 13 (beta 5) on iOS 15 (beta 5).
It appears that NSPersistentCloudkitContainer has a memory leak and keeps ramping up the RAM consumption (and CPU at 100%) until the operating system kills the app. No code of mine is running.
I'm not really an expert on these things and I tried to use Instruments to see if that would show me anything. It appears to be related to NSCloudkitMirroringDelegate getting 'stuck' somehow but I have no idea what to do with this information.
My Core Data database is not tiny, but not massive by any means and NSPersistentCloudkitContainer has had no problems syncing to iCloud prior to iOS 15 (beta 4).
If I restore my App Data (from an external backup file - 700MB with lots of many-many, many-one relationships, ckAssets, etc.) the data all gets added to Core Data without an issue at all. The console log (see below) then shows that a sync is created, scheduled & then started... but no data is uploaded.
At this point the memory consumption starts and all I see is 'backgroundTask' warnings appear (only related to CloudKit) with no code of mine running.
CoreData: CloudKit: CoreData+CloudKit: -[PFCloudKitExporter analyzeHistoryInStore:withManagedObjectContext:error:](501): <PFCloudKitExporter: 0x600000301450>: Exporting changes since (0): <NSPersistentHistoryToken - {
"4B90A437-3D96-4AC9-A27A-E0F633CE5D9D" = 906;
}>
CoreData: CloudKit: CoreData+CloudKit: -[PFCloudKitExportContext processAnalyzedHistoryInStore:inManagedObjectContext:error:]_block_invoke_3(251): Finished processing analyzed history with 29501 metadata objects to create, 0 deleted rows without metadata.
CoreData: CloudKit: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _scheduleAutomatedExportWithLabel:activity:completionHandler:](2800): <NSCloudKitMirroringDelegate: 0x6000015515c0> - Beginning automated export - ExportActivity:
<CKSchedulerActivity: 0x60000032c500; containerID=<CKContainerID: 0x600002ed3240; containerIdentifier=iCloud.com.nitramluap.Somnus, containerEnvironment="Sandbox">, identifier=com.apple.coredata.cloudkit.activity.export.4B90A437-3D96-4AC9-A27A-E0F633CE5D9D, priority=2, xpcActivityCriteriaOverrides={ Priority=Utility }>
CoreData: CloudKit: CoreData+CloudKit: -[NSCloudKitMirroringDelegate executeMirroringRequest:error:](765): <NSCloudKitMirroringDelegate: 0x6000015515c0>: Asked to execute request: <NSCloudKitMirroringExportRequest: 0x600002ed2a30> CBE1852D-7793-46B6-8314-A681D2038B38
2021-08-13 08:41:01.518422+1000 Somnus[11058:671570] [BackgroundTask] Background Task 68 ("CoreData: CloudKit Export"), was created over 30 seconds ago. In applications running in the background, this creates a risk of termination. Remember to call UIApplication.endBackgroundTask(_:) for your task in a timely manner to avoid this.
2021-08-13 08:41:03.519455+1000 Somnus[11058:671570] [BackgroundTask] Background Task 154 ("CoreData: CloudKit Scheduling"), was created over 30 seconds ago. In applications running in the background, this creates a risk of termination. Remember to call UIApplication.endBackgroundTask(_:) for your task in a timely manner to avoid this.
Just wondering if anyone else is having a similar issue? It never had a problem syncing an initial database restore prior to iOS 15 (beta 4) and the problems started right after installing iOS 15 (beta 4).
I've submitted this to Apple Feedback and am awaiting a response (FB9412346). If this is unfixable I'm in real trouble (and my users are going to be livid).
Thanks in advance!
I have an app with fairly typical requirements - I need to insert some data (in my case from the network but could be anything) and I want to do it in the background to keep the UI responsive.
I'm using SwiftData.
I've created a ModelActor that does the importing and using the debugger I can confirm that the data is indeed being inserted.
On the UI side, I'm using @Query and a SwiftUI List to display the data but what I am seeing is that @Query is not updating as the data is being inserted. I have to quit and re-launch the app in order for the data to appear, almost like the context running the UI isn't communicating with the context in the ModelActor.
I've included a barebones sample project. To reproduce the issue, tap the 'Background Insert' button. You'll see logs that show items being inserted but the UI is not showing any data.
I've tested on the just released iOS 18b3 seed (22A5307f).
The sample project is here:
https://hanchor.s3.amazonaws.com/misc/SwiftDataBackgroundV2.zip
When trying to run my document-based iPad app using iPadOS 18 beta and Xcode 16 beta, I get an error like the following after opening a document:
Thread 1: Fatal error: Failed to identify a store that can hold instances of SwiftData._KKMDBackingData<MyProject.MyModel> from [:]
In order to help track down what is going wrong, I downloaded the sample app from WWDC23 session "Build an app with SwiftData" found here: https://developer.apple.com/documentation/swiftui/building-a-document-based-app-using-swiftdata
When I try to run the end-state of that sample code, I get a similar error when running the app on my iPad and creating a new deck:
Thread 1: Fatal error: Failed to identify a store that can hold instances of SwiftData._KKMDBackingData<SwiftDataFlashCardSample.Card> from [:]
Given that the sample project is generating the same error as my own project, is this a problem with SwiftData and document-based apps in general? Or is there a change of approach that I should try?
Since the iOS 18 and Xcode 16, I've been getting some really strange SwiftData errors when passing @Model classes around.
The error I'm seeing is the following:
SwiftData/BackingData.swift:409: Fatal error: This model instance was destroyed by calling ModelContext.reset and is no longer usable.
PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(url: x-coredata://34EE9059-A7B5-4484-96A0-D10786AC9FB0/TestApp/p2), implementation: SwiftData.PersistentIdentifierImplementation)
The same issue also happens when I try to retrieve a model from the ModelContext using its PersistentIdentifier and try to do anything with it. I have no idea what could be causing this.
I'm guessing this is just a bug in the iOS 18 Beta, since I couldn't find a single discussion about this on Google, I figured I'd mention it.
if someone has a workaround or something, that would be much appreciated.
Hello everyone,
I used SwiftData for v1 of an app and am now trying to make changes to the schema for v2. I created the v2 schema that adds a property to one of the models.
I need to populate the new property so I made a custom migration using didMigrate. However that doesn't seem to matter what I do in the migration because creating the ModelContainer throws an error before didMigrate ever gets called.
The error is:
Unresolved error loading container Error Domain=NSCocoaErrorDomain Code=134060 "A Core Data error occurred." UserInfo={NSLocalizedFailureReason=Instances of NSCloudKitMirroringDelegate are not reusable and should have a lifecycle tied to a given instance of NSPersistentStore.}
Higher up in the Xcode output I see things like this (in order):
Request 'D25A8CB8-7341-4FA8-B2F8-3DE2D35B5273' was cancelled because the store was removed from the coordinator.
BUG IN CLIENT OF CLOUDKIT: Registering a handler for a CKScheduler activity identifier that has already been registered
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.
How can I know from this output what I am doing incorrectly?
Any idea what I should take a look at or try to do differently?
This is a simple app with three models and nothing fancy. The only change in the schema is to add a property. The new property is declared as optional and has an inverse that is also declared as optional.
Thanks for any insight!
Hi everyone,
Have anybody faced with Core Data issues, trying to migrate the project to Xcode16 beta 4?
We are using transformableAttributeType in some entities, with attributeValueClassName = "[String]" and valueTransformerName = "NSSecureUnarchiveFromData". It is working just fine for years, but now I am trying to run the project from Xcode16 and have 2 issues:
in Xcode logs I see warning and error:
CoreData: fault: Declared Objective-C type "[String]" for attribute named alertBarChannels is not valid
CoreData: Declared Objective-C type "[String]" for attribute named alertBarChannels is not valid
periodically the app crashes when we are assigning value to this attribute, with error:
Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFConstantString characterAtIndex:]: Range or index out of bounds'
Once again, in Xcode 15 it works fine, and it was working for years.
Cannot find any information about what was changed in the framework...
Thank you in advance for any information, which could clarify what is going on.
I am using SwiftData to model my data. For that i created a model called OrganizationData that contains various relationships to other entities. My data set is quite large and i am having a big performance issue when fetching all OrganizationData entities. I started debugging and looking at the sql debug log i noticed that when fetching my entities i run into faults for all relationships even when not accessing them.
Fetching my entities:
let fetchDescriptor = FetchDescriptor<OrganizationData>()
let context = MapperContext(dataManager: self)
let organizations = (try modelContainer.mainContext.fetch(fetchDescriptor))
Doing this fetch, also fetches all relationships. Each in a single query, for every OrganizationData entity.
CoreData: annotation: to-many relationship fault "relationship1" for objectID 0x8aa5249772916e00 <x-coredata://B891FCEB-DF16-4E11-98E6-0AFB5D171A81/OrganizationData/p3869> fulfilled from database. Got 9 rows
CoreData: annotation: to-many relationship fault "relationship2" for objectID 0x8aa5249772916e00 <x-coredata://B891FCEB-DF16-4E11-98E6-0AFB5D171A81/OrganizationData/p3869> fulfilled from database. Got 0 rows
CoreData: annotation: to-many relationship fault "relationship3" for objectID 0x8aa5249772916e00 <x-coredata://B891FCEB-DF16-4E11-98E6-0AFB5D171A81/OrganizationData/p3869> fulfilled from database. Got 0 rows
CoreData: annotation: to-many relationship fault "relationship4" for objectID 0x8aa5249772916e00 <x-coredata://B891FCEB-DF16-4E11-98E6-0AFB5D171A81/OrganizationData/p3869> fulfilled from database. Got 0 rows
CoreData: annotation: to-many relationship fault "relationship5" for objectID 0x8aa5249772916e00 <x-coredata://B891FCEB-DF16-4E11-98E6-0AFB5D171A81/OrganizationData/p3869> fulfilled from database. Got 0 rows
CoreData: annotation: to-many relationship fault "relationship6" for objectID 0x8aa5249772916e00 <x-coredata://B891FCEB-DF16-4E11-98E6-0AFB5D171A81/OrganizationData/p3869> fulfilled from database. Got 0 rows
CoreData: annotation: to-many relationship fault "relationship7" for objectID 0x8aa5249772916e00 <x-coredata://B891FCEB-DF16-4E11-98E6-0AFB5D171A81/OrganizationData/p3869> fulfilled from database. Got 1 rows
CoreData: annotation: to-many relationship fault "relationship8" for objectID 0x8aa5249772916e00 <x-coredata://B891FCEB-DF16-4E11-98E6-0AFB5D171A81/OrganizationData/p3869> fulfilled from database. Got 0 rows
CoreData: annotation: to-many relationship fault "relationship9" for objectID 0x8aa5249772916e00 <x-coredata://B891FCEB-DF16-4E11-98E6-0AFB5D171A81/OrganizationData/p3869> fulfilled from database. Got 0 rows
The relationships are all defined the same
@Relationship(deleteRule: .cascade, inverse: \EntityData1.organization)
var relationship1: [EntityData1] = []
Am i missing something? As far as i understood relationships are lazy and should only be faulted when accessing the property. But doing the fetch as described above already causes a query to happen, making the fetch take very long when using a large data set.
Hi,
I'm struggling with SwiftData and the components for migration and could really use some guidance. My specific questions are
Is it possible to go from an unversioned schema to a versioned schema?
Do all @Model classes need to be converted?
Is there one VersionedSchema for the entire app that handles all models or one VersionedSchema per model?
What is the relationship, if any, between the models given to ModelContainer in a [Schema] and the models in the VersionedSchema in a [any PersistentModel.Type]
I have an app in the AppStore. I use SwiftData and have four @Models defined. I was not aware of VersionedSchema when I started, so they are unversioned. I want to update the model and am trying to convert to a VersionedSchema. I've tried various things and can't even get into the migration plan yet. All posts and tutorials that I've come across only deal with one Model, and create a VersionedSchema for that model.
I've tried to switch the one Model I want to update, as well as switching them all. Of course I get different errors depending on what configuration I try.
It seems like I should have one VersionedSchema for the app since there is the static var models: [any PersistentModel.Type] property. Yet the tutorials I've seen create a TypeNameSchemaV1 to go with the @Model TypeName.
Which is correct? An AppNameSchemaV1 which defines four models, or four TypeNameSchemaV1?
Any help will be much appreciated
I have an app that uses CKShare to allow users to share CloudKit data with other users.
With the first build of the iOS 26, I'm seeing a few issues:
I'm not able to add myself as a participant anymore when I have the link to a document.
Some participants names no longer show up in the app.
Looking at the release notes for iOS & iPadOS 26 Beta, there is a CloudKit section with two bullets:
CloudKit sharing URLs do not launch third-party apps. (151778655)
The request access APIs, such as CKShareRequestAccessOperation, are available in the SDK but are currently nonfunctional. (151878020)
It sounds like the first issue is addressed by the first bullet, although the error message makes me wonder if I need to make changes to my iCloud account permissions or something in order to open it. It works fine in iOS 18.5. This is the error I get when I try to open a link to a shared document (I blocked out my email address, which is what was in quotes):
As far as the second issue, I am really confused about what is going on. Some names still show up, while others do not. I can't find a pattern, and the missing users are not on the iOS 26 beta. The release notes mention CKShareRequestAccessOperation being nonfunctional, which is new in the beta and has some minor documentation, but I can't find information about how it's supposed to be used yet.
In previous years there have been WWDC sessions about what's new in CloudKit, but I haven't found anything that talks about these changes to document sharing.
Is there a guide or session somewhere that I'm missing?
Does anyone know what's going on with these changes to CloudKit?
I just released an App update the didn't touch ANYTHING to do with Core Data (nothing changed in our Coredata code for at least 8 months). The update uses SDK for iOS 18 and Xcode 16.2 and the app now requires iOS 18 and was a minor bug patch and UI improvements for recent iOS changes.
Since the update we are getting a steady trickle of users on iOS 18, some who allow the App to store data in iCloud (Cloudkit) and others who do not, all reporting that after the update to our recent release ALL their data is gone?!
I had not seen this on ANY device until today when I asked a friend who uses the App if they had the issue and it turned out they did, so I hooked their device up to Xcode and ALL the data in the CoreData database was gone?! They are NOT using iCloud. There were no errors or exceptions on Xcode console but a below code returned NO records at all?!
Chart is custom entity and is defined as:
@interface Chart : NSManagedObject {}
let moc = pc.viewContext
let chartsFetch = NSFetchRequest<NSFetchRequestResult>(entityName:"Charts") // Fetch all Charts
do {
let fetchedCharts = try moc.fetch(chartsFetch) as! [Chart]
for chart in fetchedCharts {
....
}
}
A break point inside the do on fetchedCharts show there are NO objects returned.
This is a serious issue and seems like an iOS 18 thing. I saw some people talking in here about NSFetchRequest issues with iOS 18. I need some guidance here from someone Apple engineer here who knows what the status of these NSFetchrequest bugs are and what possible workarounds are. Becasue this problem will grow for me as more users update to iOS 18.
I have an app that uses NSPersistentCloudKitContainer stored in a shared location via App Groups so my widget can fetch data to display. It works. But if you reset your iPhone and restore it from a backup, an error occurs:
The file "Name.sqlite" couldn't be opened. I suspect this happens because the widget is created before the app's data is restored. Restarting the iPhone is the only way to fix it though, opening the app and reloading timelines does not. Anything I can do to fix that to not require turning it off and on again?
I'm unable to view Changes or Diff View in the Deploy Schema Changes Dialog due to an Internal Error.
I have a few apps that use Core Data & CloudKit to sync data to multiple devices. Everything was fine until I updated to Xcode 14. Now, although the apps work on an actual device, in the simulator, I get errors about "Failed to sync user keys" and it won't sync anything.
I haven't changed the code at all. It just suddenly won't work in the simulator. Since it does this for all apps, I have to believe it's something changed with the simulator?
2022-09-13 12:47:26.766223-0400 Time Since[8061:88974] [error] error: CoreData+CloudKit: -[NSCloudKitMirroringDelegate _performSetupRequest:]_block_invoke(1134): <NSCloudKitMirroringDelegate: 0x600003b540e0>: Failed to set up CloudKit integration for store: <NSSQLCore: 0x1219071d0> (URL: file:///Users/jon/Library/Developer/CoreSimulator/Devices/1990772E-CDF1-4A58-B454-E09D327B2182/data/Containers/Data/Application/3314EA95-4D86-4053-84B3-F1523A57E204/Library/Application%20Support/TimeSince.sqlite)
<CKError 0x600000cc1e60: "Partial Failure" (2/1011); "Failed to modify some record zones"; partial errors: {
com.apple.coredata.cloudkit.zone:__defaultOwner__ = <CKError 0x600000cc2160: "Internal Error" (1/5000); "Failed to sync user keys">
}>
I'm still getting this error (SwiftData/ModelContext.swift:3253: Fatal error: Failed to identify a store that can hold instances of SwiftData._KKMDBackingData<Presents_2024.Item> from [:]) in Xcode 16.1 Beta (16B5001e).
The app works for a limited amount of time and then crashes with this error. It looks like the SwiftData model isn't being created properly and when a context is saved it crashes.
Can you tell me if this error will be fixed in the next beta?
Topic:
App & System Services
SubTopic:
iCloud & Data
Tags:
Xcode
Xcode Sanitizers and Runtime Issues
Core Data
SwiftData
Hi,
I am currently experiencing some trouble when using parent model property in a predicate of a child model.
I have an Item class that define parent-child relationship:
@Model class Item {
var timestamp: Date
@Relationship(inverse: \Item.children)
var parent: Item?
var children: [Item]
init(parent: Item? = nil, children: [Item] = [], timestamp: Date = .now) {
self.parent = parent
self.children = children
self.timestamp = timestamp
}
}
I subclass this model like that:
@available(iOS 26, *)
@Model final class CollectionItem: Item { /* ... */ }
When i make a Query in my View like that the system crashes:
@Query(
filter: #Predicate<CollectionItem> { $0.parent == nil },
sort: \CollectionItem.name,
)
private var collections: [CollectionItem]
CrashReportError: Fatal Error in DataUtilities.swift
AppName crashed due to fatalError in DataUtilities.swift at line 85.
Couldn't find \CollectionItem.<computed 0x000000034005d4e8 (Optional<Item>)> on CollectionItem with fields [SwiftData.Schema.PropertyMetadata(name: "name", keypath: \CollectionItem.<computed 0x000000034003c120 (String)>, defaultValue: nil, metadata: nil), SwiftData.Schema.PropertyMetadata(name: "icon", keypath: \CollectionItem.<computed 0x000000034003ca04 (Optional<String>)>, defaultValue: nil, metadata: nil), SwiftData.Schema.PropertyMetadata(name: "timestamp", keypath: \Item.<computed 0x0000000340048018 (Date)>, defaultValue: nil, metadata: nil), SwiftData.Schema.PropertyMetadata(name: "parent", keypath: \Item.<computed 0x0000000340048a4c (Optional<Item>)>, defaultValue: nil, metadata: Optional(Relationship - name: , options: [], valueType: Any, destination: , inverseName: nil, inverseKeypath: Optional(\Item.<computed 0x0000000340048fe8 (Array<Item>)>))), SwiftData.Schema.PropertyMetadata(name: "children", keypath: \Item.<computed 0x0000000340048fe8 (Array<Item>)>, defaultValue: nil, metadata: nil)]
When I query as Item it works but then i cannot sort on CollectionItem field and must add unnecessary down casting:
@Query(
filter: #Predicate<Item> { $0.parent == nil && $0 is CollectionItem },
)
private var items: [Item]
Am I missing something? Is it a platform limitation or a known issue?
My question
Is there a way to perform an iCloud keychain reset in order to be able to test CKErrorUserDidResetEncryptedDataKey ?
I found this section in the CloudKit documentation
https://developer.apple.com/documentation/cloudkit/encrypting-user-data#Handle-a-User-Keychain-Reset
I want to be prepared for the zoneNotFound / CKErrorUserDidResetEncryptedDataKey case.
However, I can't find a way to actually reproduce this error with an iCloud (test-) user and can't find any Apple documentation on how to perform sucha "User Keychain Reset".
The only thing that almost looked like it I came across was in the Keychain.app's Settings "Reset Default Keychains…". However, performing this didn't seem to affect the CloudKit data used in our App at all.
I've been trying to do this with an Apple account that has 2FA active and a recovery account assigned.
We're only targetting >= iOS 18, macOS >= 15.
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 "***" and name "yyy"
before the changes are uploaded, there are new changes from many OTHER BACKGROUND THREADS made to the database. item "***"'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 "***" as finished uploading or not? If I mark *** as finished that's wrong, the new name "zzz" is not uploaded.
I have to compare every field of *** 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?
Topic:
App & System Services
SubTopic:
iCloud & Data
Tags:
iOS
CloudKit
Cloud and Local Storage
Core Data
Recently I've been working on a demo project called iLibrary. The main goal was to learn more about CloudKit and SwiftData. After a while I noticed that there were some hangs/freezes when running the app in debug mode.
I first tried this with Xcode 15.4 and iOS 17.5. Here the hang only appears at the beginning, but only for a few seconds. But when I exit debug mode, there are no more hangs.
With Xcode 16 beta 4 and iOS 18 it looks completely different. In this case, the hangs and freezes are always present, whether in debug mode or not. And it's not just at the beginning, it's throughout the app. I'm aware that this is still a beta, but I still find this weird. And when I profile this I see that the main thread gets quite overloaded. Interestingly, my app doesn't have that many operations going on. So I guess something with the sync of SwiftData or my CloudKitManger where I fetch some records from the public database is not running fine.
Lastly, I wanted to delete the iCloud app data. So I went to Settings and tried to delete it, but it didn't work. Is this normal?
Does anyone have any idea what this could be? Or has anyone encountered this problem as well? I'd appreciate any support.
My project: https://github.com/romanindermuehle/iLibrary