public static INetStream <TKey, TMessage> ToTopic <TKey, TMessage, TResponseKey, TResponse>( this IHandle <TKey, TMessage, TResponseKey, TResponse> handle, string topic, Func <TResponse, TResponseKey> resolveKey) { handle.Write(new KafkaTopicWriter <TKey, TMessage, TResponseKey, TResponse>(topic, new ProducerFactory(), handle, resolveKey)); return(handle.Stream); }