Question

I override NSURLProtocol and need to return HTTP response with specific statusCode. NSHTTPURLResponse does not have statusCode setter, so I tried to override it with:

@interface MyHTTPURLResponse : NSHTTPURLResponse {} 

@implementation MyHTTPURLResponse

    - (NSInteger)statusCode {
        return 200; //stub code
    }
@end

Overridden startLoading method of NSURLProtocol looks like this:

-(void)startLoading
{   
   NSString *url = [[[self request] URL] absoluteString];
   if([url isEqualToString:SPECIFIC_URL]){
       MyURLResponse *response = [[MyURLResponse alloc] initWithURL:[NSURL URLWithString:@"http://fakeUrl"]
       MIMEType:@"text/plain"
       expectedContentLength:0  textEncodingName:nil];

       [[self client] URLProtocol:self     
            didReceiveResponse:response 
            cacheStoragePolicy:NSURLCacheStorageNotAllowed];

       [[self client] URLProtocol:self didLoadData:[@"Fake response string"
            dataUsingEncoding:NSASCIIStringEncoding]];

       [[self client] URLProtocolDidFinishLoading:self];                

       [response release];

    }
    else{   
        [NSURLConnection connectionWithRequest:[self request] delegate:self];   
    }
}

But this approach does not work, the response created in NSURLProtocol is always with statusCode = 0 on web page. At the same time responses that are returned from network by NSURLConnection have normal expected statusCodes.

Can anyone please help with ideas how to set statusCode explicitly for created NSURLResponse? Thanx.

Answer 1

I’ve implemented custom init method using following code:

    NSInteger statusCode = 200;
    id headerFields = nil;
    double requestTime = 1;

    SEL selector = NSSelectorFromString(@"initWithURL:statusCode:headerFields:requestTime:");
    NSMethodSignature *signature = [self methodSignatureForSelector:selector];

    NSInvocation *inv = [NSInvocation invocationWithMethodSignature:signature];
    [inv setTarget:self];
    [inv setSelector:selector];
    [inv setArgument:&URL atIndex:2];
    [inv setArgument:&statusCode atIndex:3];
    [inv setArgument:&headerFields atIndex:4];
    [inv setArgument:&requestTime atIndex:5];

    [inv invoke];