grpc-client.go

package main

import (
	"context"
	"crypto/tls"
	"crypto/x509"
	"fmt"
	"io/ioutil"
	"time"

	pb "google.golang.org/grpc/examples/helloworld/helloworld"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials"
)

func main() {
	var opts []grpc.DialOption

	peerCert, err :=
		tls.LoadX509KeyPair(
			"./certificate/client/out/service1.crt",
			"./certificate/client/out/service1.pkcs8.pem")
	if err != nil {
		panic(err)
	}
	caCert, err := ioutil.ReadFile("./certificate/ca/ca.crt")
	if err != nil {
		panic(err)
	}
	caCertPool := x509.NewCertPool()
	caCertPool.AppendCertsFromPEM(caCert)
	creds := credentials.NewTLS(&tls.Config{
		Certificates: []tls.Certificate{peerCert},
		RootCAs:      caCertPool,
	})

	opts = append(opts, grpc.WithTransportCredentials(creds))

	conn, err := grpc.Dial("dev-grpc-server.example.com:443", opts...)
	if err != nil {
		panic(err)
	}
	defer conn.Close()
	client := pb.NewGreeterClient(conn)

	for i := 0; i < 60; i++ {
		ctx, _ := context.WithTimeout(context.Background(), time.Second)
		reply, err := client.SayHello(ctx, &echo.HelloRequest{Name: "Hello" + time.Now().String()})
		if err != nil {
			fmt.Println(err)
		} else {
			fmt.Println(reply.Reply)
		}
		time.Sleep(time.Second)
	}
}