appFinishLaunchingWithOptions for seeding your CoreData with RestKit

gistfile1.m

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Initialize RestKit
	RKObjectManager* objectManager = [RKObjectManager objectManagerWithBaseURL:@"http://twitter.com"];
    
    // Enable automatic network activity indicator management
    objectManager.client.requestQueue.showsNetworkActivityIndicatorWhenBusy = YES;
    
    // Initialize object store
    #ifdef RESTKIT_GENERATE_SEED_DB
        NSString *seedDatabaseName = nil;
        NSString *databaseName = RKDefaultSeedDatabaseFileName;
    #else
        NSString *seedDatabaseName = RKDefaultSeedDatabaseFileName;
        NSString *databaseName = @"RKTwitterData.sqlite";
    #endif

    objectManager.objectStore = [RKManagedObjectStore objectStoreWithStoreFilename:databaseName usingSeedDatabaseName:seedDatabaseName managedObjectModel:nil delegate:self];
    
    /*!
     Map to a target object class -- just as you would for a non-persistent class. The entity is resolved
     for you using the Active Record pattern where the class name corresponds to the entity name within Core Data.
     Twitter status objects will be mapped onto RKTStatus instances.
     */
    RKManagedObjectMapping* statusMapping = [RKManagedObjectMapping mappingForClass:[RKTStatus class]];
    statusMapping.primaryKeyAttribute = @"statusID";
    [statusMapping mapKeyPathsToAttributes:@"id", @"statusID",
     @"created_at", @"createdAt",
     @"text", @"text",
     @"url", @"urlString",
     @"in_reply_to_screen_name", @"inReplyToScreenName",
     @"favorited", @"isFavorited", 
     nil];
    
    // Register our mappings with the provider
    [objectManager.mappingProvider setMapping:statusMapping forKeyPath:@"status"];

#ifdef RESTKIT_GENERATE_SEED_DB
    RKLogConfigureByName("RestKit/ObjectMapping", RKLogLevelInfo);
    RKLogConfigureByName("RestKit/CoreData", RKLogLevelTrace);
    RKManagedObjectSeeder* seeder = [RKManagedObjectSeeder objectSeederWithObjectManager:objectManager];
    
    // Seed the database with instances of RKTStatus from a snapshot of the RestKit Twitter timeline
    [seeder seedObjectsFromFile:@"restkit.json" withObjectMapping:statusMapping];
    
    // Finalize the seeding operation and output a helpful informational message
    [seeder finalizeSeedingAndExit];
    
    // NOTE: If all of your mapped objects use keyPath -> objectMapping registration, you can perform seeding in one line of code:
    // [RKManagedObjectSeeder generateSeedDatabaseWithObjectManager:objectManager fromFiles:@"users.json", nil];
#endif
    
    // Create Window and View Controllers
	RKTwitterViewController* viewController = [[[RKTwitterViewController alloc] initWithNibName:nil bundle:nil] autorelease];
	UINavigationController* controller = [[UINavigationController alloc] initWithRootViewController:viewController];
	UIWindow* window = [[UIWindow alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];
    [window addSubview:controller.view];
    [window makeKeyAndVisible];

    return YES;
}