Question

I am changing my app from using a purely remote DB to pulling the remote DB into a local DB. I am getting this Error when I am trying to get an Array of Objects from the remote database.

CoreData: error: Failed to call designated initializer on NSManagedObject class 'Class'

I am not sure what I am doing wrong. Here is my restkit setup.

RKObjectManager *manager = [RKObjectManager managerWithBaseURL:[NSURL URLWithString:@"http://fake.herokuapp.com"]];
  NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"App" withExtension:@"momd"];
  NSManagedObjectModel *managedObjectModel = [[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL];
  RKManagedObjectStore *managedObjectStore = [[RKManagedObjectStore alloc] initWithManagedObjectModel:managedObjectModel];
  manager.managedObjectStore = managedObjectStore; 

  RKEntityMapping *classMapping = [RKEntityMapping mappingForEntityForName:@"Class" inManagedObjectStore:managedObjectStore]; 
  [classMapping        addAttributeMappingsFromDictionary:[Class      propertyMappings]];

  NSIndexSet *statusCodes = RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful); 
  RKResponseDescriptor *classDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:classMapping pathPattern:@"/class.json" keyPath:@"" statusCodes:statusCodes];
  [manager addResponseDescriptorsFromArray:@[classDescriptor]];
  [managedObjectStore createManagedObjectContexts];
   managedObjectStore.managedObjectCache = [[RKInMemoryManagedObjectCache alloc] initWithManagedObjectContext:managedObjectStore.persistentStoreManagedObjectContext];
  [RKObjectManager setSharedManager:manager];

And here is the request I am making, where it fails ( i think on the response).

    [manager getObjectsAtPath:@"class.json" parameters:nil success:^(RKObjectRequestOperation *operation, RKMappingResult *mappingResult){
    NSLog(@"Success");

    }failure:^(RKObjectRequestOperation *operation, NSError *error) {}];

If you need anything else just let me know.
And if you could help out I will be a very happy developer.

Thank you,

-DO

EDIT

This is what propertMappings returns

+ (NSDictionary *) propertyMappings{return @{@"id" : @"iD", @"name" : @"name", @"image_url" : @"image_url"};}

Answer 1

Well the problem was actually that the Entity I was trying to pull in was nested through a few relationships in my model so it wasn’t the parent. It was causing an error. I had to adjust my api a little bit and everything worked.

Thanks for your help.

-DO