revert opentelemetry example

Author: purnesh42H

examples/features/csm_observability/server/main.go

@@ -44,6 +44,7 @@ var (
 	prometheusEndpoint = flag.String("prometheus_endpoint", ":9464", "the Prometheus exporter endpoint")
 )
 
+// server is used to implement helloworld.GreeterServer.
 type server struct {
 	pb.UnimplementedGreeterServer
 	addr string

examples/features/opentelemetry/client/main.go

@@ -29,20 +29,17 @@ import (
 
 	"google.golang.org/grpc"
 	"google.golang.org/grpc/credentials/insecure"
-	pb "google.golang.org/grpc/examples/helloworld/helloworld"
+	"google.golang.org/grpc/examples/features/proto/echo"
 	"google.golang.org/grpc/stats/opentelemetry"
 
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"go.opentelemetry.io/otel/exporters/prometheus"
 	"go.opentelemetry.io/otel/sdk/metric"
 )
 
-const defaultName = "world"
-
 var (
 	addr               = flag.String("addr", ":50051", "the server address to connect to")
 	prometheusEndpoint = flag.String("prometheus_endpoint", ":9465", "the Prometheus exporter endpoint")
-	name               = flag.String("name", defaultName, "Name to greet")
 )
 
 func main() {
@@ -61,14 +58,14 @@ func main() {
 		log.Fatalf("Failed to start NewClient: %v", err)
 	}
 	defer cc.Close()
-	c := pb.NewGreeterClient(cc)
+	c := echo.NewEchoClient(cc)
 
 	// Make an RPC every second. This should trigger telemetry to be emitted from
 	// the client and the server.
 	for {
-		r, err := c.SayHello(ctx, &pb.HelloRequest{Name: *name})
+		r, err := c.UnaryEcho(ctx, &echo.EchoRequest{Message: "this is examples/opentelemetry"})
 		if err != nil {
-			log.Fatalf("Could not greet: %v", err)
+			log.Fatalf("UnaryEcho failed: %v", err)
 		}
 		fmt.Println(r)
 		time.Sleep(time.Second)

examples/features/opentelemetry/server/main.go

@@ -22,12 +22,13 @@ package main
 import (
 	"context"
 	"flag"
+	"fmt"
 	"log"
 	"net"
 	"net/http"
 
 	"google.golang.org/grpc"
-	pb "google.golang.org/grpc/examples/helloworld/helloworld"
+	pb "google.golang.org/grpc/examples/features/proto/echo"
 	"google.golang.org/grpc/stats/opentelemetry"
 
 	"github.com/prometheus/client_golang/prometheus/promhttp"
@@ -40,15 +41,13 @@ var (
 	prometheusEndpoint = flag.String("prometheus_endpoint", ":9464", "the Prometheus exporter endpoint")
 )
 
-// server is used to implement helloworld.GreeterServer.
-type server struct {
-	pb.UnimplementedGreeterServer
+type echoServer struct {
+	pb.UnimplementedEchoServer
 	addr string
 }
 
-// SayHello implements helloworld.GreeterServer
-func (s *server) SayHello(_ context.Context, in *pb.HelloRequest) (*pb.HelloReply, error) {
-	return &pb.HelloReply{Message: "Hello " + in.GetName()}, nil
+func (s *echoServer) UnaryEcho(_ context.Context, req *pb.EchoRequest) (*pb.EchoResponse, error) {
+	return &pb.EchoResponse{Message: fmt.Sprintf("%s (from %s)", req.Message, s.addr)}, nil
 }
 
 func main() {
@@ -66,7 +65,7 @@ func main() {
 		log.Fatalf("Failed to listen: %v", err)
 	}
 	s := grpc.NewServer(so)
-	pb.RegisterGreeterServer(s, &server{addr: *addr})
+	pb.RegisterEchoServer(s, &echoServer{addr: *addr})
 
 	log.Printf("Serving on %s\n", *addr)