110 lines
4.7 KiB
Markdown
110 lines
4.7 KiB
Markdown
|
# OpenTracing
|
|||
|
|
|||
|
[OpenTracing](https://opentracing.io/) 是 CNCF 提出的分布式追踪的标准,它提供用厂商中立的 API,并提供 Go、Java、JavaScript、Python、Ruby、PHP、Objective-C、C++ 和 C# 这九种语言的库。
|
|||
|
|
|||
|
目前支持 Tracer 包括 Zipkin、Skywalking、Jaeger 等,支持的框架包括 gRPC、MOTAN、django、Flask、Sharding-JDBC 等,详见 [OpenTracing 官网](https://opentracing.io/)。
|
|||
|
|
|||
|
Jaeger 是遵循 OpenTracing 的一种实现。
|
|||
|
|
|||
|
![Jaeger UI](https://ws4.sinaimg.cn/large/006tNbRwly1fwjg48fh7xj31kw0wedrg.jpg)
|
|||
|
|
|||
|
关于 OpenTracing 的详细约定请参考:
|
|||
|
|
|||
|
- [OpenTracing 语义规范(Semantic Specification)](https://github.com/opentracing/specification/blob/master/specification.md)
|
|||
|
- [OpenTracing 语义约定(Semantic Conventions)](https://github.com/opentracing/specification/blob/master/semantic_conventions.md)
|
|||
|
|
|||
|
## 基本术语
|
|||
|
|
|||
|
如下是 OpenTracing 中定义的基本术语。
|
|||
|
|
|||
|
**Trace**
|
|||
|
|
|||
|
Trace 通常指一次完整的调用链。如上文中的 Jaeger UI 截图就是 Istio 官方提供的 [Bookinfo 示例](https://istio.io/zh/docs/examples/bookinfo/) 的追踪中对 `productpage` 的调用链分析。
|
|||
|
|
|||
|
**Span**
|
|||
|
|
|||
|
每个 trace 都由一系列 Span 组成,一个 span 可以理解为两个微服务之间的调用,如同 Chrome 检查器中查看网络访问瀑布一样。
|
|||
|
|
|||
|
![](https://ws2.sinaimg.cn/large/006tNbRwly1fwjkfbvfluj30y70hf0y9.jpg)
|
|||
|
|
|||
|
根据 OpenTracing 的规格约定,每个 Span 都要包含以下状态:
|
|||
|
|
|||
|
- **操作名称**:可以是访问的一个 URL。必填。例如 `localhost:8808/`。
|
|||
|
- **起/止时间戳**:也可以使用起始时间和持续时间来表示。必填。例如 `1540273832696773`。
|
|||
|
- **Tags**:一组键值对集合,[Semantic Conventions](https://github.com/opentracing/specification/blob/master/semantic_conventions.md) 有一些常用约定。必填。例如 `http.protocol`。
|
|||
|
- **Logs**:一组键值对集合,用于记录调用日志。可选填。
|
|||
|
- **SpanContext**:在进程间通信时携带的 span 信息,指整个 trace。
|
|||
|
|
|||
|
**示例**
|
|||
|
|
|||
|
下面是 Jaeger 收集的来自 [Bookinfo 示例](https://istio.io/zh/docs/examples/bookinfo/) 中的 `productpage` 的调用链追踪数据。
|
|||
|
|
|||
|
```json
|
|||
|
{
|
|||
|
"data": [
|
|||
|
{
|
|||
|
"traceID": "aaccbe962478cf93",
|
|||
|
"spans": [
|
|||
|
{
|
|||
|
"traceID": "aaccbe962478cf93",
|
|||
|
"spanID": "fa36a9cbd60b4ae5",
|
|||
|
"operationName": "details.default.svc.cluster.local:9080/*",
|
|||
|
"references": [
|
|||
|
{
|
|||
|
"refType": "CHILD_OF",
|
|||
|
"traceID": "aaccbe962478cf93",
|
|||
|
"spanID": "2"
|
|||
|
}
|
|||
|
],
|
|||
|
"startTime": 1540273832696773,
|
|||
|
"duration": 8171,
|
|||
|
"tags": [
|
|||
|
{
|
|||
|
"key": "component",
|
|||
|
"type": "string",
|
|||
|
"value": "proxy"
|
|||
|
},
|
|||
|
{
|
|||
|
"key": "node_id",
|
|||
|
"type": "string",
|
|||
|
"value": "sidecar~172.33.5.11~productpage-v1-8584c875d8-4jgwg.default~default.svc.cluster.local"
|
|||
|
}
|
|||
|
...
|
|||
|
],
|
|||
|
"logs": [],
|
|||
|
"processID": "p1",
|
|||
|
"warnings": null
|
|||
|
},
|
|||
|
...
|
|||
|
],
|
|||
|
"processes": {
|
|||
|
"p1": {
|
|||
|
"serviceName": "productpage",
|
|||
|
"tags": [
|
|||
|
{
|
|||
|
"key": "ip",
|
|||
|
"type": "string",
|
|||
|
"value": "172.33.5.11"
|
|||
|
}
|
|||
|
]
|
|||
|
},
|
|||
|
...
|
|||
|
},
|
|||
|
"warnings": null
|
|||
|
}
|
|||
|
],
|
|||
|
"total": 0,
|
|||
|
"limit": 0,
|
|||
|
"offset": 0,
|
|||
|
"errors": null
|
|||
|
}
|
|||
|
```
|
|||
|
|
|||
|
在开发应用时需要使用兼容 OpenTracing API 的 Tracing 实现库,例如 [Jaeger](https://www.jaegertracing.io) 来实现自动的分布式追踪。参考[在 Istio 中使用分布式追踪](https://istio.io/zh/docs/tasks/telemetry/distributed-tracing/)。
|
|||
|
|
|||
|
## 参考
|
|||
|
|
|||
|
- [OpenTracing 官方网站](https://opentracing.io/)
|
|||
|
- [OpenTracing 语义规范(Semantic Specification)](https://github.com/opentracing/specification/blob/master/specification.md)
|
|||
|
- [OpenTracing 语义约定(Semantic Conventions)](https://github.com/opentracing/specification/blob/master/semantic_conventions.md)
|
|||
|
- [开放分布式追踪(OpenTracing)入门与 Jaeger 实现](https://yq.aliyun.com/articles/514488#19)
|