Add "service.instance.id" to every span (#199)

* Add serviceInstanceId to every span, add test, add uuid package to go mod

* Bump to latest

* lint

* Use google uuid package

* Update to use WithAttributes instead

go.mod

@@ -29,6 +29,8 @@ require (
 	google.golang.org/protobuf v1.28.1
 )
 
+require github.com/google/uuid v1.1.2
+
 require (
 	cloud.google.com/go v0.81.0 // indirect
 	github.com/cenkalti/backoff/v4 v4.1.3 // indirect

go.sum

@@ -183,6 +183,7 @@ github.com/google/pprof v0.0.0-20201203190320-1bf35d6f28c2/go.mod h1:kpwsk12EmLe
 github.com/google/pprof v0.0.0-20210122040257-d980be63207e/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
 github.com/google/pprof v0.0.0-20210226084205-cbba55b83ad5/go.mod h1:kpwsk12EmLew5upagYY7GY0pfYCcupk39gWOCRROcvE=
 github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
+github.com/google/uuid v1.1.2 h1:EVhdT+1Kseyi1/pUmXKaFxYsDNy9RQYkMWRH68J/W7Y=
 github.com/google/uuid v1.1.2/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+vpHVxEJEs9eg=
 github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=

instrumentation/opentelemetry/init_test.go

@@ -81,8 +81,11 @@ func TestOtlpService(t *testing.T) {
 	shutdown := Init(cfg)
 	defer shutdown()
 
-	_, tp, err := RegisterService("custom_service", map[string]string{"test1": "val1"})
+	startSpan, tp, err := RegisterService("custom_service", map[string]string{"test1": "val1"})
+	_, s, _ := startSpan(context.Background(), "test_span", nil)
+	assert.False(t, s.IsNoop())
 	assert.NotEqual(t, trace.NewNoopTracerProvider(), tp)
+	assert.Len(t, s.GetAttributes().GetValue("service.instance.id"), 36)
 	if err != nil {
 		log.Fatalf("Error while initializing service: %v", err)
 	}
@@ -364,9 +367,12 @@ func TestInitWithSpanProcessorWrapper(t *testing.T) {
 	defer shutdown()
 
 	// test wrapper is called for spans created by global trace provider
-	_, _, spanEnder := StartSpan(context.Background(), "my_span", nil)
+	_, span, spanEnder := StartSpan(context.Background(), "my_span", nil)
+	id1 := span.GetAttributes().GetValue("service.instance.id")
 	spanEnder()
 
+	assert.Len(t, id1, 36)
+
 	// my_span and startup spans
 	assert.Equal(t, 2, wrapper.onStartCount)
 	assert.Equal(t, 2, wrapper.onEndCount)
@@ -377,7 +383,10 @@ func TestInitWithSpanProcessorWrapper(t *testing.T) {
 		log.Fatalf("Error while initializing service: %v", err)
 	}
 
-	_, _, spanEnder = startSpan(context.Background(), "service_span", nil)
+	_, serviceSpan, spanEnder := startSpan(context.Background(), "service_span", nil)
+	id2 := serviceSpan.GetAttributes().GetValue("service.instance.id")
+	assert.Len(t, id2, 36)
+	assert.Equal(t, id1, id2)
 	spanEnder()
 
 	// service_span, my_span and startup spans

instrumentation/opentelemetry/internal/identifier/identifier.go

@@ -0,0 +1,12 @@
+package identifier
+
+import (
+	"github.com/google/uuid"
+	"go.opentelemetry.io/otel/attribute"
+)
+
+var ServiceInstanceIDAttr = attribute.StringValue(uuid.New().String())
+
+const ServiceInstanceIDKey = "service.instance.id"
+
+var ServiceInstanceKeyValue = attribute.KeyValue{Key: ServiceInstanceIDKey, Value: ServiceInstanceIDAttr}

instrumentation/opentelemetry/span.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/hypertrace/goagent/instrumentation/opentelemetry/internal/identifier"
 	"github.com/hypertrace/goagent/sdk"
 	"github.com/hypertrace/goagent/version"
 	"go.opentelemetry.io/otel"
@@ -111,17 +112,18 @@ func startSpan(provider getTracerProvider) sdk.StartSpan {
 
 		if opts != nil {
 			startOpts = append(startOpts, trace.WithSpanKind(mapSpanKind(opts.Kind)))
-
 			if opts.Timestamp.IsZero() {
 				startOpts = append(startOpts, trace.WithTimestamp(time.Now()))
 			} else {
 				startOpts = append(startOpts, trace.WithTimestamp(opts.Timestamp))
 			}
 		}
+		startOpts = append(startOpts, trace.WithAttributes(identifier.ServiceInstanceKeyValue))
 
 		ctx, span := provider().
 			Tracer(TracerDomain, trace.WithInstrumentationVersion(version.Version)).
 			Start(ctx, name, startOpts...)
+
 		return ctx, &Span{span}, func() { span.End() }
 	}
 }

instrumentation/opentelemetry/span_test.go

@@ -3,6 +3,7 @@ package opentelemetry
 import (
 	"context"
 	"errors"
+	"fmt"
 	"testing"
 	"time"
 
@@ -48,6 +49,16 @@ func TestSetAttributeSuccess(t *testing.T) {
 	s.SetAttribute("test_key_4", errors.New("xyz"))
 }
 
+func TestSpanHasSameServiceInstanceId(t *testing.T) {
+	_, original, _ := StartSpan(context.Background(), "test_span", &sdk.SpanOptions{})
+	firstId := original.GetAttributes().GetValue("service.instance.id")
+	for i := 0; i < 300; i++ {
+		_, anotherSpan, _ := StartSpan(context.Background(), fmt.Sprintf("%s%d", "test_span", i), &sdk.SpanOptions{})
+		nextId := anotherSpan.GetAttributes().GetValue("service.instance.id")
+		assert.Equal(t, firstId, nextId)
+	}
+}
+
 func TestGenerateAttribute(t *testing.T) {
 	assert.Equal(t, attribute.BOOL, generateAttribute("key", true).Value.Type())
 	assert.Equal(t, attribute.BOOLSLICE, generateAttribute("key", []bool{true}).Value.Type())