AFNetworkingClient + Retry logics

AFNetworkingClient.m

//
//  AFNetworkingClient+Retry
//
//  Created by Sergii Nezdolii on 2014-09-23.
//
//

@interface AFNetworkingClient : NSObject

@property (strong, readonly) AFHTTPRequestOperationManager *manager;
+ (AFNetworkingClient *) sharedInstance;
- (void)getSomeDataWithSuccess:(void (^)(id responseObject))success
                       failure:(void (^)(NSError *error))failure
               numberOfRetries:(NSUInteger)numberOfRetries;

@end


@implementation AFNetworkingClient

static AFNetworkingClient *instance;

- (instancetype)init {
    if (self = [super init]) {
        _manager = [AFHTTPRequestOperationManager manager];
        _manager.requestSerializer = [AFJSONRequestSerializer serializer];
        _manager.responseSerializer = [AFJSONResponseSerializer serializer];
    }

    return self;
}

+ (AFNetworkingClient *)sharedInstance {
    static dispatch_once_t _singletonPredicate;

    dispatch_once(&_singletonPredicate, ^{
        instance = [AFNetworkingClient new];
    });

    return instance;
}

- (void)getSomeDataWithSuccess:(void (^)(id responseObject))success
                       failure:(void (^)(NSError *error))failure
               numberOfRetries:(NSUInteger)numberOfRetries {

    NSString *someUrl = @"https://api.github.com/users/snezdoliy/repos"
    [self GET:someUrl parameters:nil 
      success:^(AFHTTPRequestOperation *operation, id responseObject) {
          if(success) {
              success(responseObject);
          }
      } 
      failure:^(AFHTTPRequestOperation *operation, NSError *error) {
          if(failure) {
              failure(error);
          }
      } numberOfRetries:numberOfRetries prevFailureOperation:nil prevFailureError:nil];
}


#pragma mark - Helper methods to handle Retry properly

- (void)GET:(NSString *)url parameters:(id)parameters
    success:(void (^)(AFHTTPRequestOperation *operation, id responseObject))success
    failure:(void (^)(AFHTTPRequestOperation *operation, NSError *error))failure
    numberOfRetries:(NSUInteger)numberOfRetries
    prevFailureOperation:(AFHTTPRequestOperation *)prevFailureOperation
    prevFailureError:(NSError *)prevFailureError {

    if(numberOfRetries <= 0) {
        if (failure) {
            failure(prevFailureOperation, prevFailureError);
        }
    } else {
        [_manager GET:url parameters:parameters success:^(AFHTTPRequestOperation *operation, id responseObject) {
            if (success) {
                success(operation, responseObject);
            }
        } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
            [self GET:url parameters:parameters
                              success:success
                              failure:failure
                      numberOfRetries:numberOfRetries-1
                 prevFailureOperation:operation
                     prevFailureError:error];
        }];
    }

}

@end