前言

本文主要讲述golang如何接入开放式链路追踪（opentracing）。

OpenTracing-Go-Plugins介绍

opentracing-go-plugins是一个opentracing-go插件库。
该插件库支持net/http、grpc、gin、goredis、gorm等。

如何接入

引入包

go get -u github.com/yuewokeji/opentracing-go-plugins

初始化tracer

我们以jaeger为例，先创建tracer实例，再调用方法opentracing.GlobalTracer()设置一个全局的tracer

package main

import (
    "github.com/opentracing/opentracing-go"
    "github.com/uber/jaeger-client-go"
    "github.com/uber/jaeger-client-go/transport"
    "io"
)

func initJaeger(service, url string) (opentracing.Tracer, io.Closer) {
    sender := transport.NewHTTPTransport(url)
    reporter := jaeger.NewRemoteReporter(sender, jaeger.ReporterOptions.Logger(jaeger.StdLogger))

    // samples 100% of traces
    tracer, closer := jaeger.NewTracer(service, jaeger.NewConstSampler(true), reporter)
    return tracer, closer
}

func initGlobalTracer() io.Closer {
    // the closer can be used in shutdown hooks
    tracer, closer := initJaeger("hello-world", "https://your-reporter-url")

    opentracing.SetGlobalTracer(tracer)
    return closer
}

gin接入

package main

import (
    "github.com/gin-gonic/gin"
    "github.com/yuewokeji/opentracing-go-plugins/module/otgin"
)

func main() {
    server := gin.New()
    server.Use(otgin.NewMiddleware(server))

    //do something
}

net/http客户端接入

package main

import (
    "github.com/yuewokeji/opentracing-go-plugins/module/othttp"
    "net/http"
    "strings"
)

func main() {
    client := othttp.WrapClient(&http.Client{})
    req, err := http.NewRequest("GET", "https://github.com", strings.NewReader(""))
    if err != nil {
        panic(err)
    }

    resp, err := client.Do(req)
    if err != nil {
        panic(err)
    }

    // do something
}

是不是非常简单！！！