title: IOS Restkit null mapping result
body: <p>I'm unable to map my JSON to model with RestKit. Logger on XCode says</p>
  
  <pre><code>2013-09-12 16:35:00.543 EMoney[1291:342f] T restkit.object_mapping:RKMappingOperation.m:902 Performing mapping operation: &lt;RKMappingOperation 0x20155890&gt; for 'EMEcommerceInquiryResponse' object. Mapping values from object {
  } to object *nil description* with object mapping (null)
  2013-09-12 16:35:00.550 EMoney[1291:342f] T restkit.object_mapping:RKMappingOperation.m:571 Did not find mappable attribute value keyPath 'status'
  </code></pre>
  
  <p>Here is the json response</p>
  
  <pre><code>response.body={"status":"NOT_ENOUGH_CREDITS","statusdesc":"no credits"}
  </code></pre>
  
  <p>Here is my mapping code</p>
  
  <pre><code>RKObjectMapping *ecommerceInquiryMapping = [RKObjectMapping mappingForClass:[EMEcommerceInquiryResponse class]];
      [ecommerceInquiryMapping addAttributeMappingsFromArray:@[@"status",@"statusdesc"]];
      RKResponseDescriptor *responseEcommerceInquiryDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:ecommerceInquiryMapping
                                                                                                     pathPattern:EM_API_SPECIAL_OFFER_INQUIRY
                                                                                                         keyPath:nil
                                                                                                     statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)];
      [objectManager addResponseDescriptor:responseEcommerceInquiryDescriptor];
  </code></pre>
  
  <p>And here is my object class</p>
  
  <pre><code>#import &lt;Foundation/Foundation.h&gt;
  
  @interface EMEcommerceInquiryResponse : NSObject
  @property (retain, nonatomic) NSString *status;
  @property (retain, nonatomic) NSString *statusdesc;
  @end
  </code></pre>
  
  <p>This is the log when I tried to print the status</p>
  
  <pre><code>2013-09-12 17:06:55.042 EMoney[1343:907] STATUS (null)
  </code></pre>
  
  <p>Anyone have any idea what's wrong with my code? I use similar code for other mappings and they work fine.</p>