@Bean(initMethod = "start")
  KafkaCollector kafka(
      ZipkinKafkaCollectorProperties properties,
      CollectorSampler sampler,
      CollectorMetrics metrics,
      StorageComponent storage) {
    return properties.toBuilder().sampler(sampler).metrics(metrics).storage(storage).build();
  }
This collector consumes a topic, decodes spans from thrift messages and stores them subject to
sampling policy.
zipkin-server/src/main/java/zipkin2/server/internal/kafka/ZipkinKafkaCollectorConfiguration.java