Migrating a Core Data Store from iCloud to local

Question

I'm currently struggling with Core Data iCloud migration.

I want to move a store from an iCloud ubiquity container (.nosync) to a local URL. The problem is that whenever I call something like this:

[self.persistentStoreCoordinator migratePersistentStore: currentiCloudStore 
                                                  toURL: localURL 
                                                options: nil 
                                               withType: NSSQLiteStoreType 
                                                  error: &error];

I get this error:

-[NSPersistentStoreCoordinator addPersistentStoreWithType:configuration:URL:options:error:](1055): CoreData: Ubiquity:  Error: A persistent store which has been previously added to a coordinator using the iCloud integration options must always be added to the coordinator with the options present in the options dictionary. If you wish to use the store without iCloud, migrate the data from the iCloud store file to a new store file in local storage. file://localhost/Users/sch/Library/Containers/bla/Data/Documents/tmp.sqlite. This will be a fatal error in a future release

Anyone ever seen this? Maybe I'm just missing the right migration options?

Answer 1

My guess is that, based on the error message, by setting your options to nil, the PSC is unable to move the store. You probably need to get the dictionary of options for the original store and pass those along instead of setting them to nil.