Update net/http instr span name

Only use the method name because the path is likely going to have a high
cardinality.

pkg/instrumentors/bpf/net/http/server/probe.go

@@ -18,7 +18,6 @@ import (
 	"bytes"
 	"encoding/binary"
 	"errors"
-	"fmt"
 	"os"
 
 	"go.opentelemetry.io/auto/pkg/instrumentors/bpffs"
@@ -40,6 +39,8 @@ import (
 
 //go:generate go run github.com/cilium/ebpf/cmd/bpf2go -target amd64,arm64 -cc clang -cflags $CFLAGS bpf ./bpf/probe.bpf.c
 
+const instrumentedPkg = "net/http"
+
 // Event represents an event in an HTTP server during an HTTP
 // request-response.
 type Event struct {
@@ -65,7 +66,7 @@ func New() *Instrumentor {
 
 // LibraryName returns the net/http package name.
 func (h *Instrumentor) LibraryName() string {
-	return "net/http"
+	return instrumentedPkg
 }
 
 // FuncNames returns the function names from "net/http" that are instrumented.
@@ -192,7 +193,6 @@ func (h *Instrumentor) Run(eventsChan chan<- *events.Event) {
 func (h *Instrumentor) convertEvent(e *Event) *events.Event {
 	method := unix.ByteSliceToString(e.Method[:])
 	path := unix.ByteSliceToString(e.Path[:])
-	name := fmt.Sprintf("%s %s", method, path)
 
 	sc := trace.NewSpanContext(trace.SpanContextConfig{
 		TraceID:    e.SpanContext.TraceID,
@@ -201,8 +201,13 @@ func (h *Instrumentor) convertEvent(e *Event) *events.Event {
 	})
 
 	return &events.Event{
-		Library:     h.LibraryName(),
-		Name:        name,
+		Library: h.LibraryName(),
+		// We do not have a include a low-cardinality path here (there is not
+		// templatized path manifest to reference). Use the default of just the
+		// request method as the span name. See
+		// https://opentelemetry.io/docs/specs/otel/trace/semantic_conventions/http/#name
+		// for more info.
+		Name:        method,
 		Kind:        trace.SpanKindServer,
 		StartTime:   int64(e.StartTime),
 		EndTime:     int64(e.EndTime),

pkg/instrumentors/bpf/net/http/server/probe_test.go

@@ -0,0 +1,66 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package server
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+
+	"go.opentelemetry.io/auto/pkg/instrumentors/context"
+	"go.opentelemetry.io/auto/pkg/instrumentors/events"
+	"go.opentelemetry.io/otel/attribute"
+	semconv "go.opentelemetry.io/otel/semconv/v1.7.0"
+	"go.opentelemetry.io/otel/trace"
+)
+
+func TestInstrumentorConvertEvent(t *testing.T) {
+	start := time.Now()
+	end := start.Add(1 * time.Second)
+
+	traceID := trace.TraceID{1}
+	spanID := trace.SpanID{1}
+
+	i := New()
+	got := i.convertEvent(&Event{
+		StartTime: uint64(start.UnixNano()),
+		EndTime:   uint64(end.UnixNano()),
+		// "GET"
+		Method: [7]byte{0x47, 0x45, 0x54},
+		// "/foo/bar"
+		Path:        [100]byte{0x2f, 0x66, 0x6f, 0x6f, 0x2f, 0x62, 0x61, 0x72},
+		SpanContext: context.EBPFSpanContext{TraceID: traceID, SpanID: spanID},
+	})
+
+	sc := trace.NewSpanContext(trace.SpanContextConfig{
+		TraceID:    traceID,
+		SpanID:     spanID,
+		TraceFlags: trace.FlagsSampled,
+	})
+	want := &events.Event{
+		Library:     instrumentedPkg,
+		Name:        "GET",
+		Kind:        trace.SpanKindServer,
+		StartTime:   int64(start.UnixNano()),
+		EndTime:     int64(end.UnixNano()),
+		SpanContext: &sc,
+		Attributes: []attribute.KeyValue{
+			semconv.HTTPMethodKey.String("GET"),
+			semconv.HTTPTargetKey.String("/foo/bar"),
+		},
+	}
+	assert.Equal(t, want, got)
+}

test/e2e/nethttp/traces.json

@@ -45,7 +45,7 @@
                 }
               ],
               "kind": 2,
-              "name": "GET /hello",
+              "name": "GET",
               "parentSpanId": "",
               "spanId": "xxxxx",
               "status": {},