RestKit and saving to CoreData as NSManagedObject

Question

I\'m using RestKit and i want to parse and save elements to core data. I have two json files:

First (Category):

[
   {
     \"cat_id\": 3371,
     \"         


        

Answer 1

So you've created the mapping for each NSManagedObject (and they work), but now you want to establish a relationship between "Category" and "Elements".

The problem is that there isn't an information for the mapping of Elements in which Category each element belongs (the unique key is missing). So you need to add the cat_id to the Elements JSON to ensure that this keypath is available.

// Elements JSON
[
  {
    "cat_id": "1313",
    "art_id": "1",
    "node": {
      "author": "name"
    },
    "small_url": 0
  },
  ...
]
// Edit keypath in relationship mapping
[elementsMapping addPropertyMapping:[RKRelationshipMapping relationshipMappingFromKeyPath:@"cat_id" toKeyPath:@"category" withMapping:categoryMapping]];

In addition you could use the following to methods to track if the mapping works.

1) -com.apple.CoreData.SQLDebug 1 // Add in "Arguments" Tab > "Arguments Passed On Launch" 
2) RKLogConfigureByName("RestKit/*", RKLogLevelTrace); // Add to AppDelegate`

Edit

Mapping

Did you update the entity Elements in your Data Model and your NSManagedObject with the given value? Seems like you didn't.

@interface Elements : NSManagedObject

@property (nonatomic, retain) NSNumber * catId;
@property (nonatomic, retain) NSNumber * artId;
@property (nonatomic, retain) NSString * author;
@property (nonatomic, retain) NSString * title;
@property (nonatomic, retain) NSManagedObject *category;

@end

Routing

The path your using for your get request won't work because @"/detailaddress/:catId" isn't a valid path. You can on the one hand set the routing of the object manager in general or define a response description.

 // Route for get operation
 [[RKObjectManager sharedManager].router.routeSet addRoute:[RKRoute 
      routeWithClass:[Category class] 
      pathPattern:@"/detailaddress/:catId" 
      method:RKRequestMethodGET]];

 // Response descriptor taken from the Core Data same application 
 RKResponseDescriptor *responseDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:categoryMapping pathPattern:@"/detailaddress/:catId" keyPath:nil statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)];     
 [objectManager addResponseDescriptor:responseDescriptor];

 // Use general path for get request
 [[RKObjectManager sharedManager] getObjectsAtPath:@"/detailaddress" ...

But please check if the mapping and data model is set like expected first.