gistfile1.txt

@interface SomeObjectFetcher ()
@property (nonatomic, strong) NSMutableData *responseData;
@end

@implementation SomeObjectFetcher

@synthesize networkActivityDelegate = _networkActivityDelegate;

+ (SomeObjectFetcher *) sharedInstance{
    static AvailableFestivalFetcher *requestGenerator = nil;
    if(!requestGenerator)
        requestGenerator = [[AvailableFestivalFetcher alloc] init];
    
    return requestGenerator;
}

- (void)startRequest{
    self.responseData = [NSMutableData data];
    [self startConnection:@""];
}

- (void)startConnection:(NSString *)additionalParams{
    
    NSURL *remoteServerURL = [NSURL URLWithString:[NSString stringWithFormat:@"%@/festivals.json%@", remoteServerAddress, additionalParams]];
    
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:remoteServerURL
                                                           cachePolicy:NSURLRequestReloadIgnoringLocalAndRemoteCacheData
                                                       timeoutInterval:15];
    
    [request setHTTPMethod: @"GET"];
    NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
    [connection start];
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
    NSError *myError = nil;

    NSArray *res = [NSJSONSerialization JSONObjectWithData:self.responseData
                                                   options:NSJSONReadingMutableLeaves
                                                     error:&myError];
    
    //check error
    
    NSMutableArray *processedObjects = [[NSMutableArray alloc] init];
    
    for(NSDictionary* result in res) {
        [processedObjects addObject: [SomeDomainObject initWithInfo:[result objectForKey:@"itemKeyName"]]];
    }

    //notify delegate that network activity is finished
    [self.networkActivityDelegate finishedActivity];
}

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
    [self.responseData setLength:0];
}

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
    [self.responseData appendData:data];
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
    NSLog(@"Failed to retrieve items: %@", error);
    [self.networkActivityDelegate somethingWentWrong];
}

@end