iOS 11+ How to migrate existing Core Data to Shared App Group for use in extension?
solidsnake4444's answer saves my day. Here is the Swift 5.0 version.
lazy var persistentContainer: NSPersistentContainer = {
let container = NSPersistentContainer(name: "MyApp")
let storeURL = FileManager.default.containerURL(forSecurityApplicationGroupIdentifier: "group.com.my.app")!.appendingPathComponent("MyApp.sqlite")
var defaultURL: URL?
if let storeDescription = container.persistentStoreDescriptions.first, let url = storeDescription.url {
defaultURL = FileManager.default.fileExists(atPath: url.path) ? url : nil
}
if defaultURL == nil {
container.persistentStoreDescriptions = [NSPersistentStoreDescription(url: storeURL)]
}
container.loadPersistentStores(completionHandler: { [unowned container] (storeDescription, error) in
if let error = error as NSError? {
fatalError("Unresolved error \(error), \(error.userInfo)")
}
if let url = defaultURL, url.absoluteString != storeURL.absoluteString {
let coordinator = container.persistentStoreCoordinator
if let oldStore = coordinator.persistentStore(for: url) {
do {
try coordinator.migratePersistentStore(oldStore, to: storeURL, options: nil, withType: NSSQLiteStoreType)
} catch {
print(error.localizedDescription)
}
// delete old store
let fileCoordinator = NSFileCoordinator(filePresenter: nil)
fileCoordinator.coordinate(writingItemAt: url, options: .forDeleting, error: nil, byAccessor: { url in
do {
try FileManager.default.removeItem(at: url)
} catch {
print(error.localizedDescription)
}
})
}
}
})
return container
}()
I ended up getting it doing the following. The sqlite file was actually the name of my init plus .sqlite at the end.
+ (NSPersistentContainer*) GetPersistentContainer {
//Init the store.
NSPersistentContainer *_persistentContainer = [[NSPersistentContainer alloc] initWithName:@"Test_App"];
//Define the store url that is located in the shared group.
NSURL* storeURL = [[[NSFileManager defaultManager] containerURLForSecurityApplicationGroupIdentifier:@"group.Test_App"] URLByAppendingPathComponent:@"Test_App.sqlite"];
//Determine if we already have a store saved in the default app location.
BOOL hasDefaultAppLocation = [[NSFileManager defaultManager] fileExistsAtPath: _persistentContainer.persistentStoreDescriptions[0].URL.path];
//Check if the store needs migration.
BOOL storeNeedsMigration = hasDefaultAppLocation && ![_persistentContainer.persistentStoreDescriptions[0].URL.absoluteString isEqualToString:storeURL.absoluteString];
//Check if the store in the default location does not exist.
if (!hasDefaultAppLocation) {
//Create a description to use for the app group store.
NSPersistentStoreDescription *description = [[NSPersistentStoreDescription alloc] init];
//set the automatic properties for the store.
description.shouldMigrateStoreAutomatically = true;
description.shouldInferMappingModelAutomatically = true;
//Set the url for the store.
description.URL = storeURL;
//Replace the coordinator store description with this description.
_persistentContainer.persistentStoreDescriptions = [NSArray arrayWithObjects:description, nil];
}
//Load the store.
[_persistentContainer loadPersistentStoresWithCompletionHandler:^(NSPersistentStoreDescription *storeDescription, NSError *error) {
//Check that we do not have an error.
if (error == nil) {
//Check if we need to migrate the store.
if (storeNeedsMigration) {
//Create errors to track migration and deleting errors.
NSError *migrateError;
NSError *deleteError;
//Store the old location URL.
NSURL *oldStoreURL = storeDescription.URL;
//Get the store we want to migrate.
NSPersistentStore *store = [_persistentContainer.persistentStoreCoordinator persistentStoreForURL: oldStoreURL];
//Set the store options.
NSDictionary *storeOptions = @{ NSSQLitePragmasOption : @{ @"journal_mode" : @"WAL" } };
//Migrate the store.
NSPersistentStore *newStore = [_persistentContainer.persistentStoreCoordinator migratePersistentStore: store toURL:storeURL options:storeOptions withType:NSSQLiteStoreType error:&migrateError];
//Check that the store was migrated.
if (newStore && !migrateError) {
//Remove the old SQLLite database.
[[[NSFileCoordinator alloc] init] coordinateWritingItemAtURL: oldStoreURL options: NSFileCoordinatorWritingForDeleting error: &deleteError byAccessor: ^(NSURL *urlForModifying) {
//Create a remove error.
NSError *removeError;
//Delete the file.
[[NSFileManager defaultManager] removeItemAtURL: urlForModifying error: &removeError];
//If there was an error. Output it.
if (removeError) {
NSLog(@"%@", [removeError localizedDescription]);
}
}
];
//If there was an error. Output it.
if (deleteError) {
NSLog(@"%@", [deleteError localizedDescription]);
}
}
}
} else {
// Replace this implementation with code to handle the error appropriately.
// abort() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
/*
Typical reasons for an error here include:
* The parent directory does not exist, cannot be created, or disallows writing.
* The persistent store is not accessible, due to permissions or data protection when the device is locked.
* The device is out of space.
* The store could not be migrated to the current model version.
Check the error message to determine what the actual problem was.
*/
NSLog(@"Unresolved error %@, %@", error, error.userInfo);
abort();
}
}];
//Return the container.
return _persistentContainer;
}