private void ValidateTopicByName(RoutingKey topic) { using (var snsClient = new AmazonSimpleNotificationServiceClient(_awsConnection.Credentials, _awsConnection.Region)) { var(success, arn) = FindTopicByName(topic.ToValidSNSTopicName(), snsClient); if (success) { _channelTopicArn = arn; } else { throw new BrokerUnreachableException( $"Topic validation error: could not find topic {topic.ToValidSNSTopicName()}. Did you want Brighter to create infrastructure?"); } } }