Core Data iCloud sync falsely reports "appears an updated object … was deleted"

Originator:chbeer78
Number:rdar://11073403 Date Originated:19-Mar-2012 05:13 PM
Status:Open Resolved:
Product:iCloud Product Version:iOS 5.1
Classification:Serious Bug Reproducible:Always
 
Summary:
When syncing data between two instances of my app via iCloud (Core Data), sometimes the following error occurs: "appears an updated object: <object-id-url>/p287 was deleted.". In the details (below) the processed cdt file is mentioned. But the CDT file (attached), doesn't contain update information about the specified object.

The sync doesn't work from then on.

CDT snippet:
…
       <key>primaryKeys</key>
	<array>
		<string>p86</string>
		<string>p4</string>
		<string>p31</string>
	</array>
…


Details:

2012-03-19 16:48:11.643 iVocabulary3[6826:41ef] -[_PFUbiquityRecordImportOperation processObjects:withState:andImportContext:outError:](658): CoreData: Ubiquity:  Transaction log: <_PFUbiquityRecordImportOperation: 0xdaf2490>:
	localPeerIID: mobile.12DFD3C2-603D-5D06-9263-674D4D4458C7
	logScore: {
    "mobile.12DFD3C2-603D-5D06-9263-674D4D4458C7" = 0;
    "mobile.9DFEE1D5-C465-5D7C-B478-0C404DB164D8" = 1;
}
transactionLog: <PFUbiquityTransactionLog: 0xd9e4960>
	transactionLogLocation: <PFUbiquityLocation: 0xdca36d0>: /private/var/mobile/Library/Mobile Documents/7UMMMKVNA9~de~chbeer~iVocabulary/iVocabularyTransactionLogs/83326B61-0501-4C8A-86C7-9BB9BC373BAC/mobile.9DFEE1D5-C465-5D7C-B478-0C404DB164D8/83326B61-0501-4C8A-86C7-9BB9BC373BAC/zy1ml5fqillJaXtar4n1H7nbvcVWAD~grfmwMlkr2vw=/202CC597-3E30-4E59-93B3-83A00BAD0B83.1.cdt
	transactionNumber: 4

 appears an updated object: x-coredata://F5416F77-6AE5-46FC-9F9E-D3AA4042A0BE/Word/p287 was deleted.



Steps to Reproduce:
Implement an app that syncs a Core Data data store via iCloud.


Expected Results:
Working synchronization.


Actual Results:
Broken synchronization.


Regression:

Notes:

19-Mar-2012 05:13 PM Christian Beer:
'202CC597-3E30-4E59-93B3-83A00BAD0B83.1.cdt.zip' was successfully uploaded

Comments

UIManagedDocument iCloud sync seems to be broken…

Core Data creates newly inserted objects with temporary IDs. It seems iCloud syncs those temporary IDs and the other device can't find the corresponding objects to fulfill relationships, etc.

There's a thread on StackOverflow with a nice solution: http://stackoverflow.com/questions/9437159/core-data-managed-object-does-not-see-related-objects-until-restart-simulator

By chbeer78 at March 28, 2012, 11:26 a.m. (reply...)

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