jaeger之全链路追踪及span日志打印_jaeger 日志-优快云博客

1、安装 Jaeger UI

Jaeger 官方提供一个 all-in-one 的 docker 镜像，用于快速搭建测试环境

$ docker run -d --name jaeger \
  -e COLLECTOR_ZIPKIN_HTTP_PORT=9411 \
  -p 5775:5775/udp \
  -p 6831:6831/udp \
  -p 6832:6832/udp \
  -p 5778:5778 \
  -p 16686:16686 \
  -p 14268:14268 \
  -p 14250:14250 \
  -p 9411:9411 \
  jaegertracing/all-in-one:1.18

然后，您可以导航到http://localhost:16686以访问Jaeger UI。
在这里插入图片描述

2、jaeger 在项目中的使用

2.1 安装 jaeger的 Go SDK

go get -u github.com/uber/jaeger-client-go

2.2 封装 jaeger tracer 的初始化函数

// NewTracer 创建一个jaeger Tracer
func NewTracer(serviceName, addr string) (opentracing.Tracer, io.Closer, error) {
   
   
	cfg := jaegercfg.Configuration{
   
   
		ServiceName: serviceName,
		Sampler: &jaegercfg.SamplerConfig{
   
   
			Type:  jaeger.SamplerTypeConst,
			Param: 1,
		},
		Reporter: &jaegercfg.ReporterConfig{
   
   
			LogSpans:            true,
			BufferFlushInterval: 1 * time.Second,
		},
	}

	sender, err := jaeger.NewUDPTransport(addr, 0)
	if err != nil {
   
   
		return nil, nil, err
	}

	reporter := jaeger.NewRemoteReporter(sender)
	// Initialize tracer with a logger and a metrics factory
	tracer, closer, err := cfg.NewTracer(
		jaegercfg.Logger(jaeger.StdLogger),
		jaegercfg.Reporter(reporter),
	)

	return tracer, closer, err
}

2.3 在 main.go 中进行调用并设置为全局 tracer

func main() {
   
   
	tracer, io, err := utils.NewTracer(common.SRV_NAME_APIGATEWAY, common.JAEGER_ADDR)
	if err != nil {
   
   
		log.L().Bg().Fatal("unable to create tracer", zap.Error(err))
	}
	defer io.Close()
	opentracing.SetGlobalTracer(tracer)
	......
}

2.4 在API网关(gin)中使用中间件为每次请求添加SpanContexts

// TracerWrapper tracer 中间件
func TracerWrapper(c *gin.Context) {
   
   
	md := make(map[string]string)
	spanCtx, _ := opentracing.GlobalTracer().Extract(opentracing.HTTPHeaders, opentracing.HTTPHeadersCarrier(c.Request.Header))
	sp := opentracing.GlobalTracer().StartSpan(c.Request.URL.Path, opentracing.ChildOf(spanCtx))
	defer sp.Finish()

	if err := opentracing.GlobalTracer().Inject(sp.Context(),
		opentracing.TextMap,
		opentracing.TextMapCarrier(md))