You can access the “data” object directly from AFNetworking by using the “AFNetworkingOperationFailingURLResponseDataErrorKey” key so there is no need for subclassing the AFJSONResponseSerializer. You can the serialize the data into a readable dictionary.
Here is some sample code to get JSON Data :
NSData *errorData = error.userInfo[AFNetworkingOperationFailingURLResponseDataErrorKey];
NSDictionary *serializedData = [NSJSONSerialization JSONObjectWithData: errorData options:kNilOptions error:nil];
Here is the code to Get Status code in the Failure block:
NSHTTPURLResponse* r = (NSHTTPURLResponse*)task.response;
NSLog( @"success: %d", r.statusCode );