feat(otelhttp): generate New Server Metrics in otelhttp (#6411)

Co-authored-by: Damien Mathieu <[email protected]>

Author: flc1125

CHANGELOG.md

@@ -8,6 +8,10 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 ## [Unreleased]
 
+### Added
+
+- Generate server metrics with semantic conventions v1.26 in `go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp` when `OTEL_SEMCONV_STABILITY_OPT_IN` is set to `http/dup`. (#6411)
+
 ## [1.33.0/0.58.0/0.27.0/0.13.0/0.8.0/0.6.0/0.5.0] - 2024-12-12
 
 ### Added

instrumentation/net/http/otelhttp/internal/semconv/env.go

@@ -16,6 +16,10 @@ import (
 	"go.opentelemetry.io/otel/metric"
 )
 
+// OTelSemConvStabilityOptIn is an environment variable.
+// That can be set to "old" or "http/dup" to opt into the new HTTP semantic conventions.
+const OTelSemConvStabilityOptIn = "OTEL_SEMCONV_STABILITY_OPT_IN"
+
 type ResponseTelemetry struct {
 	StatusCode int
 	ReadBytes  int64
@@ -31,6 +35,11 @@ type HTTPServer struct {
 	requestBytesCounter  metric.Int64Counter
 	responseBytesCounter metric.Int64Counter
 	serverLatencyMeasure metric.Float64Histogram
+
+	// New metrics
+	requestBodySizeHistogram  metric.Int64Histogram
+	responseBodySizeHistogram metric.Int64Histogram
+	requestDurationHistogram  metric.Float64Histogram
 }
 
 // RequestTraceAttrs returns trace attributes for an HTTP request received by a
@@ -103,38 +112,56 @@ type MetricData struct {
 	ElapsedTime float64
 }
 
-var metricAddOptionPool = &sync.Pool{
-	New: func() interface{} {
-		return &[]metric.AddOption{}
-	},
-}
+var (
+	metricAddOptionPool = &sync.Pool{
+		New: func() interface{} {
+			return &[]metric.AddOption{}
+		},
+	}
 
-func (s HTTPServer) RecordMetrics(ctx context.Context, md ServerMetricData) {
-	if s.requestBytesCounter == nil || s.responseBytesCounter == nil || s.serverLatencyMeasure == nil {
-		// This will happen if an HTTPServer{} is used instead of NewHTTPServer.
-		return
+	metricRecordOptionPool = &sync.Pool{
+		New: func() interface{} {
+			return &[]metric.RecordOption{}
+		},
 	}
+)
 
-	attributes := OldHTTPServer{}.MetricAttributes(md.ServerName, md.Req, md.StatusCode, md.AdditionalAttributes)
-	o := metric.WithAttributeSet(attribute.NewSet(attributes...))
-	addOpts := metricAddOptionPool.Get().(*[]metric.AddOption)
-	*addOpts = append(*addOpts, o)
-	s.requestBytesCounter.Add(ctx, md.RequestSize, *addOpts...)
-	s.responseBytesCounter.Add(ctx, md.ResponseSize, *addOpts...)
-	s.serverLatencyMeasure.Record(ctx, md.ElapsedTime, o)
-	*addOpts = (*addOpts)[:0]
-	metricAddOptionPool.Put(addOpts)
+func (s HTTPServer) RecordMetrics(ctx context.Context, md ServerMetricData) {
+	if s.requestBytesCounter != nil && s.responseBytesCounter != nil && s.serverLatencyMeasure != nil {
+		attributes := OldHTTPServer{}.MetricAttributes(md.ServerName, md.Req, md.StatusCode, md.AdditionalAttributes)
+		o := metric.WithAttributeSet(attribute.NewSet(attributes...))
+		addOpts := metricAddOptionPool.Get().(*[]metric.AddOption)
+		*addOpts = append(*addOpts, o)
+		s.requestBytesCounter.Add(ctx, md.RequestSize, *addOpts...)
+		s.responseBytesCounter.Add(ctx, md.ResponseSize, *addOpts...)
+		s.serverLatencyMeasure.Record(ctx, md.ElapsedTime, o)
+		*addOpts = (*addOpts)[:0]
+		metricAddOptionPool.Put(addOpts)
+	}
 
-	// TODO: Duplicate Metrics
+	if s.duplicate && s.requestDurationHistogram != nil && s.requestBodySizeHistogram != nil && s.responseBodySizeHistogram != nil {
+		attributes := CurrentHTTPServer{}.MetricAttributes(md.ServerName, md.Req, md.StatusCode, md.AdditionalAttributes)
+		o := metric.WithAttributeSet(attribute.NewSet(attributes...))
+		recordOpts := metricRecordOptionPool.Get().(*[]metric.RecordOption)
+		*recordOpts = append(*recordOpts, o)
+		s.requestBodySizeHistogram.Record(ctx, md.RequestSize, *recordOpts...)
+		s.responseBodySizeHistogram.Record(ctx, md.ResponseSize, *recordOpts...)
+		s.requestDurationHistogram.Record(ctx, md.ElapsedTime, o)
+		*recordOpts = (*recordOpts)[:0]
+		metricRecordOptionPool.Put(recordOpts)
+	}
 }
 
 func NewHTTPServer(meter metric.Meter) HTTPServer {
-	env := strings.ToLower(os.Getenv("OTEL_SEMCONV_STABILITY_OPT_IN"))
+	env := strings.ToLower(os.Getenv(OTelSemConvStabilityOptIn))
 	duplicate := env == "http/dup"
 	server := HTTPServer{
 		duplicate: duplicate,
 	}
 	server.requestBytesCounter, server.responseBytesCounter, server.serverLatencyMeasure = OldHTTPServer{}.createMeasures(meter)
+	if duplicate {
+		server.requestBodySizeHistogram, server.responseBodySizeHistogram, server.requestDurationHistogram = CurrentHTTPServer{}.createMeasures(meter)
+	}
 	return server
 }
 
@@ -148,7 +175,7 @@ type HTTPClient struct {
 }
 
 func NewHTTPClient(meter metric.Meter) HTTPClient {
-	env := strings.ToLower(os.Getenv("OTEL_SEMCONV_STABILITY_OPT_IN"))
+	env := strings.ToLower(os.Getenv(OTelSemConvStabilityOptIn))
 	client := HTTPClient{
 		duplicate: env == "http/dup",
 	}

instrumentation/net/http/otelhttp/internal/semconv/httpconv.go

@@ -7,10 +7,13 @@ import (
 	"fmt"
 	"net/http"
 	"reflect"
+	"slices"
 	"strconv"
 	"strings"
 
 	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/metric"
+	"go.opentelemetry.io/otel/metric/noop"
 	semconvNew "go.opentelemetry.io/otel/semconv/v1.26.0"
 )
 
@@ -199,6 +202,86 @@ func (n CurrentHTTPServer) Route(route string) attribute.KeyValue {
 	return semconvNew.HTTPRoute(route)
 }
 
+func (n CurrentHTTPServer) createMeasures(meter metric.Meter) (metric.Int64Histogram, metric.Int64Histogram, metric.Float64Histogram) {
+	if meter == nil {
+		return noop.Int64Histogram{}, noop.Int64Histogram{}, noop.Float64Histogram{}
+	}
+
+	var err error
+	requestBodySizeHistogram, err := meter.Int64Histogram(
+		semconvNew.HTTPServerRequestBodySizeName,
+		metric.WithUnit(semconvNew.HTTPServerRequestBodySizeUnit),
+		metric.WithDescription(semconvNew.HTTPServerRequestBodySizeDescription),
+	)
+	handleErr(err)
+
+	responseBodySizeHistogram, err := meter.Int64Histogram(
+		semconvNew.HTTPServerResponseBodySizeName,
+		metric.WithUnit(semconvNew.HTTPServerResponseBodySizeUnit),
+		metric.WithDescription(semconvNew.HTTPServerResponseBodySizeDescription),
+	)
+	handleErr(err)
+	requestDurationHistogram, err := meter.Float64Histogram(
+		semconvNew.HTTPServerRequestDurationName,
+		metric.WithUnit(semconvNew.HTTPServerRequestDurationUnit),
+		metric.WithDescription(semconvNew.HTTPServerRequestDurationDescription),
+	)
+	handleErr(err)
+
+	return requestBodySizeHistogram, responseBodySizeHistogram, requestDurationHistogram
+}
+
+func (n CurrentHTTPServer) MetricAttributes(server string, req *http.Request, statusCode int, additionalAttributes []attribute.KeyValue) []attribute.KeyValue {
+	num := len(additionalAttributes) + 3
+	var host string
+	var p int
+	if server == "" {
+		host, p = SplitHostPort(req.Host)
+	} else {
+		// Prioritize the primary server name.
+		host, p = SplitHostPort(server)
+		if p < 0 {
+			_, p = SplitHostPort(req.Host)
+		}
+	}
+	hostPort := requiredHTTPPort(req.TLS != nil, p)
+	if hostPort > 0 {
+		num++
+	}
+	protoName, protoVersion := netProtocol(req.Proto)
+	if protoName != "" {
+		num++
+	}
+	if protoVersion != "" {
+		num++
+	}
+
+	if statusCode > 0 {
+		num++
+	}
+
+	attributes := slices.Grow(additionalAttributes, num)
+	attributes = append(attributes,
+		semconvNew.HTTPRequestMethodKey.String(standardizeHTTPMethod(req.Method)),
+		n.scheme(req.TLS != nil),
+		semconvNew.ServerAddress(host))
+
+	if hostPort > 0 {
+		attributes = append(attributes, semconvNew.ServerPort(hostPort))
+	}
+	if protoName != "" {
+		attributes = append(attributes, semconvNew.NetworkProtocolName(protoName))
+	}
+	if protoVersion != "" {
+		attributes = append(attributes, semconvNew.NetworkProtocolVersion(protoVersion))
+	}
+
+	if statusCode > 0 {
+		attributes = append(attributes, semconvNew.HTTPResponseStatusCode(statusCode))
+	}
+	return attributes
+}
+
 type CurrentHTTPClient struct{}
 
 // RequestTraceAttrs returns trace attributes for an HTTP request made by a client.

instrumentation/net/http/otelhttp/internal/semconv/httpconv_test.go

@@ -9,11 +9,72 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 
 	"go.opentelemetry.io/otel/attribute"
 	"go.opentelemetry.io/otel/codes"
 )
 
+func TestCurrentHttpServer_MetricAttributes(t *testing.T) {
+	defaultRequest, err := http.NewRequest("GET", "http://example.com/path?query=test", nil)
+	require.NoError(t, err)
+
+	tests := []struct {
+		name                 string
+		server               string
+		req                  *http.Request
+		statusCode           int
+		additionalAttributes []attribute.KeyValue
+		wantFunc             func(t *testing.T, attrs []attribute.KeyValue)
+	}{
+		{
+			name:                 "routine testing",
+			server:               "",
+			req:                  defaultRequest,
+			statusCode:           200,
+			additionalAttributes: []attribute.KeyValue{attribute.String("test", "test")},
+			wantFunc: func(t *testing.T, attrs []attribute.KeyValue) {
+				require.Len(t, attrs, 7)
+				assert.ElementsMatch(t, []attribute.KeyValue{
+					attribute.String("http.request.method", "GET"),
+					attribute.String("url.scheme", "http"),
+					attribute.String("server.address", "example.com"),
+					attribute.String("network.protocol.name", "http"),
+					attribute.String("network.protocol.version", "1.1"),
+					attribute.Int64("http.response.status_code", 200),
+					attribute.String("test", "test"),
+				}, attrs)
+			},
+		},
+		{
+			name:                 "use server address",
+			server:               "example.com:9999",
+			req:                  defaultRequest,
+			statusCode:           200,
+			additionalAttributes: nil,
+			wantFunc: func(t *testing.T, attrs []attribute.KeyValue) {
+				require.Len(t, attrs, 7)
+				assert.ElementsMatch(t, []attribute.KeyValue{
+					attribute.String("http.request.method", "GET"),
+					attribute.String("url.scheme", "http"),
+					attribute.String("server.address", "example.com"),
+					attribute.Int("server.port", 9999),
+					attribute.String("network.protocol.name", "http"),
+					attribute.String("network.protocol.version", "1.1"),
+					attribute.Int64("http.response.status_code", 200),
+				}, attrs)
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := CurrentHTTPServer{}.MetricAttributes(tt.server, tt.req, tt.statusCode, tt.additionalAttributes)
+			tt.wantFunc(t, got)
+		})
+	}
+}
+
 func TestNewMethod(t *testing.T) {
 	testCases := []struct {
 		method   string

instrumentation/net/http/otelhttp/internal/semconv/test/go.mod

@@ -6,6 +6,7 @@ require (
 	github.com/stretchr/testify v1.10.0
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.58.0
 	go.opentelemetry.io/otel v1.33.0
+	go.opentelemetry.io/otel/metric v1.33.0
 	go.opentelemetry.io/otel/sdk v1.33.0
 	go.opentelemetry.io/otel/sdk/metric v1.33.0
 )
@@ -17,7 +18,6 @@ require (
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	go.opentelemetry.io/auto/sdk v1.1.0 // indirect
-	go.opentelemetry.io/otel/metric v1.33.0 // indirect
 	go.opentelemetry.io/otel/trace v1.33.0 // indirect
 	golang.org/x/sys v0.28.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect