public override void Invoke(AWSCredentials creds, RegionEndpoint region, int maxItems)
        {
            AmazonIoTConfig config = new AmazonIoTConfig();

            config.RegionEndpoint = region;
            ConfigureClient(config);
            AmazonIoTClient client = new AmazonIoTClient(creds, config);

            ListTopicRuleDestinationsResponse resp = new ListTopicRuleDestinationsResponse();

            do
            {
                ListTopicRuleDestinationsRequest req = new ListTopicRuleDestinationsRequest
                {
                    NextToken = resp.NextToken
                    ,
                    MaxResults = maxItems
                };

                resp = client.ListTopicRuleDestinations(req);
                CheckError(resp.HttpStatusCode, "200");

                foreach (var obj in resp.DestinationSummaries)
                {
                    AddObject(obj);
                }
            }while (!string.IsNullOrEmpty(resp.NextToken));
        }