[gRPC Channelz] show trace on client connection

client.go

package main

import (
	"context"
	"github.com/golang/protobuf/ptypes"
	"google.golang.org/grpc/reflection"
	"log"
	"net"
	"os"
	"time"

	pb "github.com/castaneai/grpc-book/src/chap01/hello-grpc"
	"google.golang.org/grpc"
	channelzpb "google.golang.org/grpc/channelz/grpc_channelz_v1"
	channelzsvc "google.golang.org/grpc/channelz/service"
)

const (
	address = "localhost:50051"
)

func main() {
	s := grpc.NewServer()
	reflection.Register(s)
	channelzsvc.RegisterChannelzServiceToServer(s)
	lis, err := net.Listen("tcp", ":5000")
	if err != nil {
		log.Fatalf("failed to listen: %v", err)
	}

	go func() {
		ctx, cancel := context.WithTimeout(context.Background(), time.Second)
		defer cancel()

		client(ctx)

		conn, err := grpc.Dial("localhost:5000", grpc.WithInsecure())
		zc := channelzpb.NewChannelzClient(conn)
		res, err := zc.GetTopChannels(ctx, &channelzpb.GetTopChannelsRequest{StartChannelId: 0})
		if err != nil {
			log.Fatal(err)
		}
		if res.Channel != nil && len(res.Channel) > 0 {
			ch := res.Channel[0]
			log.Printf("--- [channel (id: %v)]", ch.Ref.ChannelId)
			for _, ev := range ch.GetData().GetTrace().Events {
				ts, err := ptypes.Timestamp(ev.Timestamp)
				if err != nil {
					log.Fatalf("ts parse error: %+v", ev.Timestamp)
				}
				log.Printf("[%v] %+v", ts, ev.Description)
			}
		}
	}()

	if err := s.Serve(lis); err != nil {
		log.Fatalf("failed to serve: %v", err)
	}
}

func client(ctx context.Context) {
	conn, err := grpc.Dial(address, grpc.WithInsecure())
	if err != nil {
		log.Fatalf("did not connect: %v", err)
	}
	defer conn.Close()

	c := pb.NewGreeterClient(conn)
	name := os.Args[1]

	r, err := c.SayHello(ctx, &pb.HelloRequest{Name: name})
	if err != nil {
		log.Fatalf("could not greet: %v", err)
	}
	log.Printf("Greeting: %s", r.Message)
}