Add "peer.service" semantic to standard attributes (#898)

Co-authored-by: Liz Fong-Jones <lizf@honeycomb.io>

CHANGELOG.md

@@ -8,6 +8,10 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 ## [Unreleased]
 
+### Added
+
+- Add `peer.service` semantic attribute. (#898)
+
 ### Changed
 
 - Update `CONTRIBUTING.md` to ask for updates to `CHANGELOG.md` with each pull request. (#879)

api/standard/trace.go

@@ -50,6 +50,13 @@ var (
 	NetTransportOther  = NetTransportKey.String("other")
 )
 
+// General attribute keys for spans.
+const (
+	// Service name of the remote service. Should equal the actual
+	// `service.name` resource attribute of the remote service, if any.
+	PeerServiceKey = kv.Key("peer.service")
+)
+
 // Standard attribute keys used to identify an authorized enduser.
 const (
 	// Username or the client identifier extracted from the access token or

example/http/client/client.go

@@ -22,6 +22,8 @@ import (
 	"log"
 
 	"go.opentelemetry.io/otel/api/kv"
+	"go.opentelemetry.io/otel/api/standard"
+	"go.opentelemetry.io/otel/api/trace"
 
 	"net/http"
 	"time"
@@ -80,7 +82,8 @@ func main() {
 			_ = res.Body.Close()
 
 			return err
-		})
+		},
+		trace.WithAttributes(standard.PeerServiceKey.String("ExampleService")))
 
 	if err != nil {
 		panic(err)

example/http/server/server.go

@@ -21,9 +21,11 @@ import (
 
 	"go.opentelemetry.io/otel/api/correlation"
 	"go.opentelemetry.io/otel/api/global"
+	"go.opentelemetry.io/otel/api/standard"
 	"go.opentelemetry.io/otel/api/trace"
 	"go.opentelemetry.io/otel/exporters/trace/stdout"
 	"go.opentelemetry.io/otel/instrumentation/httptrace"
+	"go.opentelemetry.io/otel/sdk/resource"
 	sdktrace "go.opentelemetry.io/otel/sdk/trace"
 )
 
@@ -38,7 +40,8 @@ func initTracer() {
 	// For the demonstration, use sdktrace.AlwaysSample sampler to sample all traces.
 	// In a production application, use sdktrace.ProbabilitySampler with a desired probability.
 	tp, err := sdktrace.NewProvider(sdktrace.WithConfig(sdktrace.Config{DefaultSampler: sdktrace.AlwaysSample()}),
-		sdktrace.WithSyncer(exporter))
+		sdktrace.WithSyncer(exporter),
+		sdktrace.WithResource(resource.New(standard.ServiceNameKey.String("ExampleService"))))
 	if err != nil {
 		log.Fatal(err)
 	}