server, service: added running as effective user

app/service/service.go

@@ -4,12 +4,10 @@ import (
 	"context"
 	"crypto/tls"
 	"encoding/json"
-	"fmt"
 	"net"
 
-	"helmet/app/logger"
-
 	"helmet/app/handler"
+	"helmet/app/logger"
 	"helmet/app/operator"
 
 	"google.golang.org/grpc"
@@ -22,8 +20,7 @@ import (
 type ServiceConfig struct {
 	Handler  *handler.Handler
 	Operator *operator.Operator
-	PortNum  uint32
-	Hostname string
+	Listener net.Listener
 	X509Cert []byte
 	X509Key  []byte
 }
@@ -33,11 +30,7 @@ type Service struct {
 	hand     *handler.Handler
 	oper     *operator.Operator
 	log      *logger.Logger
-	portnum  uint32
-	hostname string
-
-	username string
-	password string
+	listen   net.Listener
 	x509Cert []byte
 	x509Key  []byte
 }
@@ -46,8 +39,7 @@ func NewService(conf *ServiceConfig) *Service {
 	svc := Service{
 		hand:     conf.Handler,
 		oper:     conf.Operator,
-		portnum:  conf.PortNum,
-		hostname: conf.Hostname,
+		listen:   conf.Listener,
 		x509Cert: conf.X509Cert,
 		x509Key:  conf.X509Key,
 	}
@@ -60,12 +52,6 @@ func (svc *Service) Run() error {
 	var err error
 	svc.log.Infof("Service run")
 
-	listenSpec := fmt.Sprintf(":%d", svc.portnum)
-	listener, err := net.Listen("tcp", listenSpec)
-	if err != nil {
-		return err
-	}
-
 	tlsCert, err := tls.X509KeyPair(svc.x509Cert, svc.x509Key)
 	if err != nil {
 		return err
@@ -75,7 +61,6 @@ func (svc *Service) Run() error {
 		ClientAuth:         tls.NoClientCert,
 		InsecureSkipVerify: true,
 	}
-
 	tlsCredentials := credentials.NewTLS(&tlsConfig)
 	if err != nil {
 		return err
@@ -87,14 +72,13 @@ func (svc *Service) Run() error {
 	gsrvOpts := []grpc.ServerOption{
 		grpc.Creds(tlsCredentials),
 		grpc.ChainUnaryInterceptor(interceptors...),
-		//grpc.UnaryInterceptor(svc.authInterceptor),
 	}
 	svc.gsrv = grpc.NewServer(gsrvOpts...)
 
 	svc.hand.Register(svc.gsrv)
 
-	svc.log.Infof("Service listening at %v", listener.Addr())
-	err = svc.gsrv.Serve(listener)
+	svc.log.Infof("Service listening at %v", svc.listen.Addr())
+	err = svc.gsrv.Serve(svc.listen)
 	if err != nil {
 		return err
 	}