免去繁琐的手动埋点，Gin 框架可观测性最佳实践

package main

import (
        "io"
        "log"
        "net/http"
        "time"

        "github.com/gin-gonic/gin"
)

func main() {
        r := gin.Default()
        r.GET("/hello-gin", func(c *gin.Context) {
                c.String(http.StatusOK, "hello\n")
        })
        go func() {
                _ = r.Run()
        }()

        // give time for auto-instrumentation to start up
        time.Sleep(5 * time.Second)
        for {
          resp, err := http.Get("http://localhost:8080/hello-gin")
          if err != nil {
                  log.Fatal(err)
          }
          body, err := io.ReadAll(resp.Body)
          if err != nil {
                  log.Fatal(err)
          }

          log.Printf("Body: %s\n", string(body))
          _ = resp.Body.Close()

          // give time for auto-instrumentation to report signal
          time.Sleep(5 * time.Second)
        }
}

const (
  SERVICE_NAME       = ""
  SERVICE_VERSION    = ""
  DEPLOY_ENVIRONMENT = ""
  HTTP_ENDPOINT      = ""
  HTTP_URL_PATH      = ""
)

// 设置应用资源
func newResource(ctx context.Context) *resource.Resource {
  hostName, _ := os.Hostname()

  r, err := resource.New(
    ctx,
    resource.WithFromEnv(),
    resource.WithProcess(),
    resource.WithTelemetrySDK(),
    resource.WithHost(),
    resource.WithAttributes(
      semconv.ServiceNameKey.String(SERVICE_NAME), // 应用名
      semconv.ServiceVersionKey.String(SERVICE_VERSION), // 应用版本
      semconv.DeploymentEnvironmentKey.String(DEPLOY_ENVIRONMENT), // 部署环境
      semconv.HostNameKey.String(hostName), // 主机名
    ),
  )

  if err != nil {
    log.Fatalf("%s: %v", "Failed to create OpenTelemetry resource", err)
  }
  return r
}

func newHTTPExporterAndSpanProcessor(ctx context.Context) (*otlptrace.Exporter, sdktrace.SpanProcessor) {

  traceExporter, err := otlptrace.New(ctx, otlptracehttp.NewClient(
    otlptracehttp.WithEndpoint(HTTP_ENDPOINT),
    otlptracehttp.WithURLPath(HTTP_URL_PATH),
    otlptracehttp.WithInsecure(),
    otlptracehttp.WithCompression(1)))

  if err != nil {
    log.Fatalf("%s: %v", "Failed to create the OpenTelemetry trace exporter", err)
  }

  batchSpanProcessor := sdktrace.NewBatchSpanProcessor(traceExporter)

  return traceExporter, batchSpanProcessor
}

// InitOpenTelemetry OpenTelemetry 初始化方法
func InitOpenTelemetry() func() {
  ctx := context.Background()

  var traceExporter *otlptrace.Exporter
  var batchSpanProcessor sdktrace.SpanProcessor

  traceExporter, batchSpanProcessor = newHTTPExporterAndSpanProcessor(ctx)

  otelResource := newResource(ctx)

  traceProvider := sdktrace.NewTracerProvider(
    sdktrace.WithSampler(sdktrace.AlwaysSample()),
    sdktrace.WithResource(otelResource),
    sdktrace.WithSpanProcessor(batchSpanProcessor))

  otel.SetTracerProvider(traceProvider)
  otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(propagation.TraceContext{}, propagation.Baggage{}))

  return func() {
    cxt, cancel := context.WithTimeout(ctx, time.Second)
    defer cancel()
    if err := traceExporter.Shutdown(cxt); err != nil {
      otel.Handle(err)
    }
  }
}

func main() {
    r := gin.Default()
    // 初始化您的OpenTelemetry
    tp, err := InitOpenTelemetry()
  if err != nil {
    log.Fatal(err)
  }
  defer func() {
    if err := tp.Shutdown(context.Background()); err != nil {
      log.Printf("Error shutting down tracer provider: %v", err)
    }
  }()
    // 添加gin的OpenTelemetry中间件实现
    r.Use(otelgin.Middleware("my-server"))
    r.GET("/hello-gin", func(c *gin.Context) {
        c.String(http.StatusOK, "hello\n")
    })
}

otel-linux-amd64 go build .

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    app.kubernetes.io/name: emoji
    app.kubernetes.io/part-of: emojivoto
    app.kubernetes.io/version: v11
  name: emoji
  namespace: emojivoto
spec:
  progressDeadlineSeconds: 600
  replicas: 1
  revisionHistoryLimit: 10
  selector:
    matchLabels:
      app: emoji-svc
      version: v11
  template:
    metadata:
      labels:
        app: emoji-svc
        version: v11
    spec:
      containers:
        - env:
            - name: HTTP
              value: '8080'
          image: 'registry.cn-hangzhou.aliyuncs.com/private-mesh/ginotel:latest'
          imagePullPolicy: Always
          name: emoji-svc
          ports:
            - containerPort: 8080
              name: grpc
              protocol: TCP
          resources:
            requests:
              cpu: 100m
          terminationMessagePath: /dev/termination-log
          terminationMessagePolicy: File
        - env:
            - name: OTEL_GO_AUTO_TARGET_EXE
              value: /usr/local/bin/app
            - name: OTEL_EXPORTER_OTLP_ENDPOINT
              value: 'http://jaeger.default.svc:4318'
            - name: OTEL_SERVICE_NAME
              value: emojivoto-emoji
          image: >-
            ghcr.io/open-telemetry/opentelemetry-go-instrumentation/autoinstrumentation-go:v0.19.0-alpha
          imagePullPolicy: IfNotPresent
          name: emojivoto-emoji-instrumentation
          resources: {}
          securityContext:
            privileged: true
            runAsUser: 0
          terminationMessagePath: /dev/termination-log
          terminationMessagePolicy: File
      dnsPolicy: ClusterFirst
      restartPolicy: Always
      schedulerName: default-scheduler
      securityContext: {}
      shareProcessNamespace: true
      terminationGracePeriodSeconds: 0