跟踪Bus Events

可以通过设置spring.cloud.bus.trace.enabled=true来跟踪总线事件（RemoteApplicationEvent的子类）。如果这样做，那么Spring Boot TraceRepository（如果存在）将显示每个发送的事件和来自每个服务实例的所有ack。示例（来自/trace端点）：

{
  "timestamp": "2015-11-26T10:24:44.411+0000",
  "info": {
  "signal": "spring.cloud.bus.ack",
  "type": "RefreshRemoteApplicationEvent",
  "id": "c4d374b7-58ea-4928-a312-31984def293b",
  "origin": "stores:8081",
  "destination": "*:**"
  }
  },
  {
  "timestamp": "2015-11-26T10:24:41.864+0000",
  "info": {
  "signal": "spring.cloud.bus.sent",
  "type": "RefreshRemoteApplicationEvent",
  "id": "c4d374b7-58ea-4928-a312-31984def293b",
  "origin": "customers:9000",
  "destination": "*:**"
  }
  },
  {
  "timestamp": "2015-11-26T10:24:41.862+0000",
  "info": {
  "signal": "spring.cloud.bus.ack",
  "type": "RefreshRemoteApplicationEvent",
  "id": "c4d374b7-58ea-4928-a312-31984def293b",
  "origin": "customers:9000",
  "destination": "*:**"
  }
}

该跟踪显示RefreshRemoteApplicationEvent从customers:9000发送到所有服务，并且已被customers:9000和stores:8081收到（acked）。

为了处理信号，您可以向您的应用添加AckRemoteApplicationEvent和SentApplicationEvent类型的@EventListener（并启用跟踪）。或者您可以利用TraceRepository并从中挖掘数据。