AFHTTPRequestOperation nil response instead of error - ios

Question

I am using AFHTTPRequestOperation to get a couple of HTML pages to parse.
The problem i'm having, is if I use a wrong port number for example, when connecting to the server, the 'failed' error block doesn't fire. Instead the completion block fires but the responce string is nil.
I'm just switching over to AFNetworking from ASIHTTP, and with ASIHTTP this would produce an error.
Surely this should provide an error? How can I trap this?
NSString *urlString;
urlString = [NSString stringWithFormat:#"%#://%#:%#/",kHttp,_IP,_Port];
NSURL *url = [NSURL URLWithString:urlString];
// Set authorization
AFHTTPClient *httpClient = [[AFHTTPClient alloc] initWithBaseURL:url];
[httpClient setAuthorizationHeaderWithUsername:_User password:_Pass];
NSURLRequest *request = [httpClient requestWithMethod:#"POST" path:#"Info.htm" parameters:nil];
AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];
[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
if ([self parseInfoLive:operation.responseString])
_count_parsed++;
if (_count_parsed == 2)
[[NSNotificationCenter defaultCenter] postNotificationName:#"downloadsComplete" object:nil];
}
failure:^(AFHTTPRequestOperation *operation, NSError *error) {
NSLog(#"Error during connection: %#",error.description);
[[NSNotificationCenter defaultCenter] postNotificationName:#"errorConnecting" object:nil];
}];
[operation start];

Answer 1

This seems to be a bug in AFNetworking, even 2.5 years after this question. This occurs when response contains a special character(it can appear as a space since sometimes even text viewers too can't parse it). You can try converting recieved JSON string to NSUTF8StringEncoding and then use it as NSData, if needed.
NSURL *url = <YOUR REQUEST URL>
NSString *data = [NSString stringWithContentsOfURL:url];
NSData *metOfficeData = [data dataUsingEncoding:NSUTF8StringEncoding];
NSError *error = [NSError new];
NSDictionary *jsonData = [NSJSONSerialization JSONObjectWithData:metOfficeData options:kNilOptions error:&error];