jaeger UI 优化,更简单
最后更新于：2022-04-02 02:57:35
[TOC]
## 概述
原生 Jaeger 仅支持将数据持久化到 cassandra 和 elasticsearch 中
## 启动 jaeger docker
`docker run -d -p 6831:6831/udp -p 16686:16686 jaegertracing/all-in-one:latest`
UI 界面为 http://127.0.0.1:16686
## 安装 jaeger-client-go
`go get github.com/uber/jaeger-client-go/...`
## 教程
### 启动一个 trace
```
func Init(service string) (opentracing.Tracer, io.Closer) {
cfg := &config.Configuration{
ServiceName: service,
Sampler: &config.SamplerConfig{
Type: "const", //全部采样
Param: 1, //1 开启全部采样,0 关闭全部采样,可通过 环境变量 JAEGER_SAMPLER_PARAM 控制
},
Reporter: &config.ReporterConfig{
LogSpans: true,
//LocalAgentHostPort: "127.0.0.1:6831",
},
}
tracer, closer, err := cfg.NewTracer( config.Logger(log.StdLogger))//log.StdLogger 只要实现日志接口即可
if err != nil {
panic(fmt.Sprintf("ERROR: cannot init Jaeger: %v\n", err))
}
return tracer, closer
}
//调用
func main(){
//初始化,只能在main 函数中初始化,因为需要 defer
tracer, closer := Init("jaeger-demo11")
defer closer.Close()
//StartspanFromContext创建新span时会用到
opentracing.SetGlobalTracer(tracer)
}
```
### 从全局获取一个 span
```
//[推荐方案]通过 opentracing 即可全局调用
span := opentracing.StartSpan("no_context")
defer span.Finish()
//等同于
tracer := opentracing.GlobalTracer()
parentSpan := tracer.StartSpan("parent")
defer parentSpan.Finish()
```
### 创建子跨度
```
parentSpan := opentracing.StartSpan("parent")
defer parentSpan.Finish()
...
childSpan := opentracing.StartSpan("child",opentracing.ChildOf(parentSpan.Context()))
defer childSpan.finish()
```
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