Another question on this problem: does anyone know if NSStoreModelVersionIdentifiers is used in looking for a source model to infer a mapping model from?
To recap: 1) Loading an existing document with the version 11 model works 2) Adding a new version (12) with a single new boolean property on one entity triggers an automatic migration but the source model is not found 3) During the failure, all hashes match between the XML store and the current model version except for the one entity I modified (so the migration is correctly triggered) 4) I've confirmed the source model can be loaded in principle by using -metadataForPersistentStoreOfType: and -mergedModelFromBundles:forStoreMetadata: 5) With the new version 12 model I can successfully create new documents then save and load them. 6) Overriding -managedObjectModel in my NSPersistentDocument to ensure the correct momd is loaded doesn't fix the problem. I'm at a bit of a loss what to try next.... Martin On Jun 18, 2013, at 08:38 AM, Dave Fernandes <dave.fernan...@utoronto.ca> wrote: > cc'ing the list this time… > > On 2013-06-18, at 2:26 AM, Martin Hewitson <martin.hewit...@aei.mpg.de> wrote: > >> >> On Jun 18, 2013, at 08:08 AM, Jerry Krinock <je...@ieee.org> wrote: >> >>> >>> On 2013 Jun 17, at 21:13, Martin Hewitson <martin.hewit...@aei.mpg.de> >>> wrote: >>> >>>> I did try making a mapping model (this is something I've done in the past >>>> in other apps) but I got the same error message. >>> >>> Oh, well. >>> >>>> Is the idea that the auto-migration magic will pick up the mapping model >>>> and use it, if it finds it? >>> >>> Yes. I think the only three things you need do are to specify the current >>> version, and add .xcdatamodel and .xcmappingmodel files to your app target. >>> Xcode compiles the .xcdatamodel files into .mom files that all get put >>> into a .momd folder which also contains a VersionInfo.plist that specifies >>> the current version and the hashes for the entities in each version; also >>> it compiles each .xcmappingmodel files into a .cdm file. Finally, the >>> .momd folder and all the .cdm files get packaged into your product's >>> Resources. Given those pieces, it's a pretty easy reverse-engineering >>> exercise to figure out what the auto-migration magic must be doing. >> >> According to your description, my app bundle's in good shape. I tried making >> a mapping model and the cdm file shows up in Resources, as expected. The >> momd folder contains all the expected mom and one omo file. >> >>> >>> Lately, Xcode has also been adding a .omo file, just one, named for the >>> current version, to the .momd. On Stack Overflow, 'Bobson' guessed that >>> this was "the same data [as the .mom file], organized differently". >>> Probably not a bad guess. Maybe optimized for faster access by Mountain >>> Lion or something. >> >> Yes, I just noticed this ono file in the app bundle. I was wondering what >> that was... >> >> <snip> >> >>>> Then I go to open an existing document and I get the dreaded "migration >>>> failed, missing source managed object model" error. >>> >>> >>> After writing this message, you know I think it's more likely that you >>> screwed up and did this… >>> >>> • Change the data model a little. >>> • Create a document, "E". >>> • Get interrupted by a fire drill. >>> • Change the data model a little more. >>> • Build. >>> >>> In this case, indeed *no* version of your app will ever be able to open >>> that document "E". If this is your "existing" document, the "migration >>> failed, missing source managed object model" error is expected. >> >> I don't think this is the case since I can still drop back to version 11 and >> open the 'existing' document. I just made a test app and managed to perform >> a lightweight migration much like the one I'm trying here, so I guess I'm >> doing something wrong. I'll try to absorb your other detailed comments and >> see if I can get some more debug output to figure out what's going on. >> >> I just had another thought.... I have another core data model in the app. I >> wonder if the NSPersistentDocument infrastructure is picking up the wrong >> model? As I'm looking through the project, I realise I don't know how the >> document knows which core data model to use.... OK, back to the >> documentation on NSPersistentDocument. >> > > By default it will merge all models in the main bundle. So if the other model > changed, you would also have a problem. If you want to specify only one model > for the document, you should override [NSPersistentDocument > managedObjectModel]. > > >> Thanks again, >> >> Martin >> >> >> >> >> >> _______________________________________________ >> >> Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) >> >> Please do not post admin requests or moderator comments to the list. >> Contact the moderators at cocoa-dev-admins(at)lists.apple.com >> >> Help/Unsubscribe/Update your Subscription: >> https://lists.apple.com/mailman/options/cocoa-dev/dave.fernandes%40utoronto.ca >> >> This email sent to dave.fernan...@utoronto.ca > _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
