Function Compute：Analisis Tracing

Daftar berikut menjelaskan detail kode contoh.

• Tambahkan dependensi.

  go get github.com/aliyun/fc-runtime-go-sdk
  go get go.opentelemetry.io/otel
  go get go.opentelemetry.io/otel/sdk
  go get go.opentelemetry.io/otel/exporters/jaeger

• Laporkan data ke Analisis Tracing.

  func HandleRequest(ctx context.Context, event MyEvent) (string, error) {
      // Obtain the tracing information of the context in Function Compute.
      fctx, ok := fccontext.FromContext(ctx)
      if !ok {
          return "", fmt.Errorf("failed to get FcContext")
      }
      spanCtx, endpoint, err := getFcTracingInfo(fctx)
      if err != nil {
          return "", fmt.Errorf("failed to getFcTracingInfo, error: %v", err)
      }
      // Create a tracer provider.
      tp, err := NewTracerProvider(endpoint)
      if err != nil {
          return "", fmt.Errorf("OpenTracingJaegerEndpoint: %s, error: %v", fctx.Tracing.JaegerEndpoint, err)
      }
      // Set the tracer provider to a global tracer provider.
      otel.SetTracerProvider(tp)
      if err != nil {
          return "", fmt.Errorf("failed to getFcSpanCtx, error: %v", err)
      }
      // Create a custom span.
      startMySpan(trace.ContextWithSpanContext(ctx, spanCtx))
      return fmt.Sprintf("hello world! Hello, %s!", event.Name), nil
  }

• Buat tracerProvider yang menyediakan akses ke tracer.

  func tracerProvider(url string) (*tracesdk.TracerProvider, error) {
      // Create a Jaeger exporter.
      exp, err := jaeger.New(jaeger.WithCollectorEndpoint(jaeger.WithEndpoint(url)))
      if err != nil {
          return nil, err
      }
      tp := tracesdk.NewTracerProvider(
          // Register an exporter.
          tracesdk.WithBatcher(exp),
          // Record the application information in the resource.
          tracesdk.WithResource(resource.NewWithAttributes(
              semconv.SchemaURL,
              semconv.ServiceNameKey.String("FCTracer"),
              attribute.String("environment", "production"),
              attribute.Int64("ID", 1),
          )),
      )
      return tp, nil
  }

• Peroleh informasi tracing dari Context dan konversikan OpenTracing SpanContext menjadi OpenTelemetry SpanContext.

  func getFcTracingInfo(fctx *fccontext.FcContext) (trace.SpanContext, string, error) {
      // Obtain the tracing information.
      spanContext := trace.SpanContext{}
      endpoint := fctx.Tracing.JaegerEndpoint
      OpenTracingSpanContext := fctx.Tracing.OpenTracingSpanContext
      if len(endpoint) == 0 {
          return spanContext, endpoint, fmt.Errorf("invalid jaeger endpoint")
      }
      spanContextSlice := strings.Split(OpenTracingSpanContext, ":")
  
      // Pad zeros in front of the trace ID.
      tid, err := trace.TraceIDFromHex("0000000000000000" + spanContextSlice[0])
      if err != nil {
          return spanContext, endpoint, err
      }
      fid := trace.FlagsSampled
      spanContext = spanContext.WithTraceID(tid).WithTraceFlags(fid).WithRemote(true)
      return spanContext, endpoint, nil
  }

• Buat tracer dan gunakan OpenTelemetry SpanContext yang telah dikonversi untuk membuat rentang anak. Rentang merepresentasikan potongan kode yang dapat dieksekusi secara berkelanjutan yang diberi nama dan diukur waktunya dalam jejak pemanggilan. Anda juga dapat membuat rentang anak dari rentang tersebut.

  func startMySpan(ctx context.Context) {
      // Use a global tracer provider.
      tr := otel.Tracer("fc-Trace")
      ctx, parentSpan := tr.Start(ctx, "fc-operation")
      defer parentSpan.End()
      parentSpan.SetAttributes(attribute.Key("version").String("fc-v1"))
      time.Sleep(150 * time.Millisecond)
      child(ctx)
  }
  
  func child(ctx context.Context) {
      tr := otel.Tracer("fc-Trace")
      _, childSpan := tr.Start(ctx, "fc-operation-child")
      defer childSpan.End()
      time.Sleep(100 * time.Millisecond)
      childSpan.AddEvent("timeout")
  }

Daftar berikut menjelaskan detail kode contoh.

• Tambahkan dependensi.

  go get github.com/aliyun/fc-runtime-go-sdk
  go get github.com/opentracing/opentracing-go
  go get github.com/uber/jaeger-client-go

• Laporkan data ke Analisis Tracing.

  func HandleRequest(ctx context.Context, event MyEvent) (string, error) {
      // Obtain the tracing information of the context in Function Compute.
      fctx, _ := fccontext.FromContext(ctx)
      endpoint := fctx.Tracing.JaegerEndpoint
      OpenTracingSpanContext := fctx.Tracing.OpenTracingSpanContext
      if len(endpoint) == 0 {
          return "", fmt.Errorf("invalid jaeger endpoint")
      }
      // Create a tracer.
      tracer, closer := NewJaegerTracer("FCTracer", endpoint)
      defer closer.Close()
      // Restore the SpanContext.
      spanContext, err := jaeger.ContextFromString(OpenTracingSpanContext)
      if err != nil {
          return "", fmt.Errorf("OpenTracingSpanContext: %s, error: %v", fctx.Tracing.OpenTracingSpanContext, err)
      }
      // Create a custom span.
      startMySpan(spanContext, tracer)
      return fmt.Sprintf("hello world! Hello, %s!", event.Name), nil
  }

• Buat objek tracer yang menyediakan akses ke tracer.

  func NewJaegerTracer(service, endpoint string) (opentracing.Tracer, io.Closer) {
      sender := transport.NewHTTPTransport(endpoint)
      tracer, closer := jaeger.NewTracer(service,
          jaeger.NewConstSampler(true),
          jaeger.NewRemoteReporter(sender))
      return tracer, closer
  }

• Konversikan SpanContext dan buat rentang kustom. Anda juga dapat membuat rentang anak dari rentang tersebut.

  func startMySpan(context jaeger.SpanContext, tracer opentracing.Tracer) {
      parentSpan := tracer.StartSpan("MyFCSpan", opentracing.ChildOf(context))
      defer parentSpan.Finish()
      parentSpan.SetOperationName("fc-operation")
      parentSpan.SetTag("version", "fc-v1")
      time.Sleep(150 * time.Millisecond)
      // Enable a child span.
      childSpan := tracer.StartSpan("fc-operation-child", opentracing.ChildOf(parentSpan.Context()))
      defer childSpan.Finish()
      time.Sleep(100 * time.Millisecond)
      childSpan.LogFields(
          log.String("type", "cache timeout"),
          log.Int("waited.millis", 100))
  }