Mapping an object to CoreData with 2 classes - ios

Question

So this is the first time i'm trying to map objects into CoreData, I think I got it right, but I have few issues. First of all, I just don't know if I'm mapping it the right way and the second one is that I get a success response but without objects mapped.
I have 2 objects DbRestError & DbRestCategory. DbRestError contain the error from the server and DbRestCategory contain the category itself. the are both coming back from the same response but RestKit seems unable to map them.
Those are the objects:
DbRestError
#interface DbRestError : NSManagedObject
#property (nonatomic, retain) NSNumber * statusCode;
#property (nonatomic, retain) NSString * errorTitle;
#end
DbRestCategory
#interface DbRestCategory : NSManagedObject
#property (nonatomic, retain) NSString * title;
#property (nonatomic, retain) NSNumber * idNum;
#end
This is how I initialize my CoreData with RestKit:
- (void)setup
{
self.objectStore = [[RKManagedObjectStore alloc] initWithManagedObjectModel:[self managedObjectModel]];
NSString *path = [RKApplicationDataDirectory() stringByAppendingPathComponent:#"database.sqlite"];
NSLog(#"Setting up store at %#", path);
[self.objectStore addSQLitePersistentStoreAtPath:path
fromSeedDatabaseAtPath:nil
withConfiguration:nil
options:#{ NSInferMappingModelAutomaticallyOption: #YES, NSMigratePersistentStoresAutomaticallyOption: #YES }
error:nil];
[self.objectStore createManagedObjectContexts];
}
This is how I initialize my RestKit client:
- (void)initRestClient
{
NSURL *baseURL = [NSURL URLWithString:kWebServiceBaseURL];
self.manager = [RKObjectManager managerWithBaseURL:baseURL];
[self.manager setRequestSerializationMIMEType:RKMIMETypeJSON];
[self.manager setAcceptHeaderWithMIMEType:RKMIMETypeJSON];
[self.manager addResponseDescriptorsFromArray:[RKObjectManager sharedManager].responseDescriptors];
[self.manager addRequestDescriptorsFromArray:[RKObjectManager sharedManager].requestDescriptors];
[self.manager.HTTPClient.operationQueue setMaxConcurrentOperationCount:MAX_CONCURRENT_OPERATION_COUNT];
[self.manager setManagedObjectStore:[[MainDb sharedDb] objectStore]];
[RKObjectManager setSharedManager:self.manager];
self.requestMethod = RKRequestMethodGET;
self.statusCode = RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful);
RKRoute *categoriesRoute = [RKRoute routeWithClass:[DbRestCategory class] pathPattern:kGetCategories method:self.requestMethod];
categoriesRoute.shouldEscapePath = YES;
[self.manager.router.routeSet addRoute:categoriesRoute];
// ##yosi -- Error Mapping
//
//
RKEntityMapping *errorMapping = [RKEntityMapping mappingForEntityForName:#"DbRestError" inManagedObjectStore:[[MainDb sharedDb] objectStore]];
[errorMapping addAttributeMappingsFromDictionary:#{ #"statusCode" : #"statusCode", #"description" : #"errorTitle" }];
// ##yosi -- Categories Mapping
//
//
RKEntityMapping *categoryMapping = [RKEntityMapping mappingForEntityForName:#"DbRestCategory" inManagedObjectStore:[[MainDb sharedDb] objectStore]];
[categoryMapping addAttributeMappingsFromDictionary:#{ #"id" : #"idNum", #"name" : #"title" }];
RKObjectMapping *categoriesMapping = [RKObjectMapping mappingForClass:[RestCategories class]];
[categoriesMapping addRelationshipMappingWithSourceKeyPath:#"categories" mapping:categoryMapping];
[categoriesMapping addPropertyMapping:[RKRelationshipMapping relationshipMappingFromKeyPath:#"error" toKeyPath:#"error" withMapping:errorMapping]];
[[RKObjectManager sharedManager] addResponseDescriptor:[RKResponseDescriptor responseDescriptorWithMapping:categoriesMapping
method:self.requestMethod
pathPattern:kGetCategories
keyPath:nil
statusCodes:self.statusCode]];
}
This is how I'm doing the request itself:
[[RKObjectManager sharedManager] getObject:[[DbRestCategory alloc] init] path:nil parameters:nil success:^(RKObjectRequestOperation *operation, RKMappingResult *mappingResult) {
} failure:^(RKObjectRequestOperation *operation, NSError *error) {
}];
This is how the JSON looks like:
{
error: {
statusCode: 10,
description: "success"
},
categories: [
{
id: "3",
name: "cate 3"
},
{
id: "4",
name: "cate 4"
},
{
id: "5",
name: "cate 5"
},
{
id: "1",
name: "cate 1"
},
{
id: "6",
name: "cate 6"
},
{
id: "2",
name: "cate 2"
}
]
}
Can someone please help me to understand why i'm getting a response without any objects?

Answer 1

Try the request mapping like this,
// Request Mapping
// Map error
RKEntityMapping *errorMapping = [RKEntityMapping mappingForEntityForName:#"DbRestError" inManagedObjectStore:[[MainDb sharedDb] objectStore]];
[errorMapping addAttributeMappingsFromDictionary:#{ #"statusCode" : #"statusCode", #"description" : #"errorTitle" }];
[[RKObjectManager sharedManager] addResponseDescriptor:[RKResponseDescriptor responseDescriptorWithMapping:errorMapping method:self.requestMethod pathPattern:kGetCategories keyPath:#"error" statusCodes:self.statusCode]];
// Map Category
RKEntityMapping *categoryMapping = [RKEntityMapping mappingForEntityForName:#"DbRestCategory" inManagedObjectStore:[[MainDb sharedDb] objectStore]];
[categoryMapping addAttributeMappingsFromDictionary:#{ #"id" : #"idNum", #"name" : #"title" }];
[[RKObjectManager sharedManager] addResponseDescriptor:[RKResponseDescriptor responseDescriptorWithMapping:categoriesMapping method:self.requestMethod pathPattern:kGetCategories keyPath:#"categories" statusCodes:self.statusCode]];