gistfile1.txt

DUETSHTTPClient *httpClient = [DUETSHTTPClient sharedHTTPClient];
  NSMutableURLRequest *request = [httpClient requestWithMethod:@"POST"
															path:@"/tokens"
													  parameters:params];

	AFJSONRequestOperation *operation = [[AFJSONRequestOperation alloc] initWithRequest:request];
	[operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
        if ([self validateRequest:operation.response]) {

        }

	} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        [self handleRequestError:error];
	}];

	[operation setDownloadProgressBlock:^(NSUInteger bytesRead, long long totalBytesRead, long long totalBytesExpectedToRead) {

	}];
	[httpClient enqueueHTTPRequestOperation:operation];