Create scaffolding of ddl-simulator

Implement global server as control plane

Implement device to get their info from global server and connect each
others

cmd/global-server/main.go

@@ -0,0 +1,51 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"net"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"git.pengzhan.dev/ddp-simulator/pkg/env"
+	"git.pengzhan.dev/ddp-simulator/pkg/global"
+	pb "git.pengzhan.dev/ddp-simulator/proto"
+	log "github.com/sirupsen/logrus"
+	"google.golang.org/grpc"
+)
+
+var (
+	ip         = flag.String("ip", "0.0.0.0", "The global server ip")
+	port       = flag.Int("port", 3200, "The global server port")
+	configPath = flag.String("config-path", "", "Config file path")
+)
+
+func init() {
+	flag.Parse()
+
+	log.SetOutput(os.Stdout)
+	log.SetLevel(log.TraceLevel)
+	// log.SetReportCaller(true)
+}
+
+func main() {
+	lis, err := net.Listen(env.PROTOCOL, fmt.Sprintf("%s:%d", *ip, *port))
+	if err != nil {
+		log.Fatalf("failed to listen: %v", err)
+	}
+	c := make(chan os.Signal, 1)
+	signal.Notify(c, os.Interrupt, syscall.SIGTERM)
+	go func() {
+		<-c
+		os.Exit(1)
+	}()
+
+	s := grpc.NewServer()
+	g := global.NewGlobalServer(*configPath)
+	pb.RegisterGlobalServiceServer(s, g)
+
+	if err := s.Serve(lis); err != nil {
+		log.Fatalf("failed to serve: %v", err)
+	}
+}