def list_topics
      response = random_broker.fetch_metadata(topics: nil)
      response.topics.select do |topic|
        topic.topic_error_code == 0
      end.map(&:topic_name)
    end
def list_topics
      response = random_broker.fetch_metadata(topics: nil)
      response.topics.select do |topic|
        topic.topic_error_code == 0
      end.map(&:topic_name)
    end
Lists all topics in the cluster.