RKObjectMapping connections - ios

Question

I have neхt response:
{
"orders": [
{
"date": "2013-11-18T13:00:39.000Z",
"state": "new",
"id": 11,
"order_item_ids": [
27,
28
]
}
],
"order_items": [
{
"count": 2,
"id": 27,
"item_id": 1,
"order_id": 11
},
{
"count": 1,
"id": 28,
"item_id": 2,
"order_id": 11
}
]
}
And next object I want to map it:
#interface Order : NSObject
#property (nonatomic, strong) NSString* state;
#property (nonatomic, strong) NSMutableArray* orderItems;
#property (nonatomic, strong) NSDate* visitDate;
#end
orderItems should be array of:
#interface OrderItem : NSObject
#property (nonatomic) NSUInteger ID;
#property (nonatomic) NSUInteger itemID;
#property (nonatomic) NSUInteger count;
#end
In case of RKEntityMapping I should use addConnectionForRelationship to map order_item_ids to orderItems array via order_items response. But what should I do to do to connect it in case of RKObjectMapping? Off course I can map both orders and orderItems with separate response descriptors and than parse it, but I want to make RestKit do it for me. Another idea is to use CoreData and RKEntityMapping but I'm not sure that I want in this case, it will be overkill in this case.

Answer 1

You can't have it done automatically with RKObjectMapping because you can't index into both arrays in any way. The entity mapping only works because you can use foreign key mapping after both mappings have been performed. You can duplicate this by using multiple response descriptors and mappings and then combining the contents of the mapping result.