restkit nested object with array mapping - objective-c

Question

I have this json:
{
"status": "ok",
"post": {
"id": 171,
"type": "locations",
"slug": "plaza-404",
"url": "http://localhost/?locations=plaza-404",
"status": "publish",
"title": "Sucursal Plaza 404",
"title_plain": "Sucursal Plaza 404",
"content": "",
"excerpt": "",
"date": "2014-03-05 19:59:50",
"modified": "2014-03-07 19:11:43",
"categories": [],
"tags": [],
"author": {
"id": 1,
"slug": "arturocalvo",
"name": "arturocalvo",
"first_name": "",
"last_name": "",
"nickname": "arturocalvo",
"url": "",
"description": ""
},
"comments": [],
"attachments": [],
"comment_count": 0,
"comment_status": "closed",
"custom_fields": {
"id": [
"1"
],
"location_id": [
"1"
],
"calle": [
"Av. Gomez Morin No.404 Local A3-5"
]
}
And i Want to map only the title the custom field called "calle", this is my interface for Location
#interface Location : NSObject
#property (nonatomic, copy) NSString * name;
#property (nonatomic, copy) NSSet * calle;
#end
and this is my code
RKObjectMapping *locationMapping = [RKObjectMapping mappingForClass:[Location class]];
RKObjectMapping *locationCustomMapping = [RKObjectMapping mappingForClass: [LocationCustom class]];
[locationMapping addAttributeMappingsFromDictionary:#{
#"title": #"name",
#"calle": #"calle"
}];
RKResponseDescriptor *locationResponseDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:locationMapping method:RKRequestMethodAny pathPattern:nil keyPath:#"post" statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)];
[objectManager addResponseDescriptor:locationResponseDescriptor];
NSURLRequest *request = [NSURLRequest requestWithURL:baseURL];
RKObjectRequestOperation *objectRequestOperation = [[RKObjectRequestOperation alloc] initWithRequest:request responseDescriptors:#[ locationResponseDescriptor ]];
But for some reason i cant map it, everythime gets a null value, can somebody help me?

Answer 1

You are missing a level in the JSON that you need to tell RestKit to navigate. Use:
#"custom_fields.calle": #"calle"
in your mapping.