[#607] cmd/node: Empty Control server address as disable

In previous implementation if Control listen endpoint was omitted in config
the gRPC listening endpoint was used instead.

Consider empty address as an option to disable the service.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

cmd/neofs-node/control.go

@@ -6,7 +6,6 @@ import (
 
 	"github.com/nspcc-dev/neofs-api-go/pkg/object"
 	controlconfig "github.com/nspcc-dev/neofs-node/cmd/neofs-node/config/control"
-	grpcconfig "github.com/nspcc-dev/neofs-node/cmd/neofs-node/config/grpc"
 	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/engine"
 	"github.com/nspcc-dev/neofs-node/pkg/services/control"
 	controlSvc "github.com/nspcc-dev/neofs-node/pkg/services/control/server"
@@ -14,6 +13,11 @@ import (
 )
 
 func initControlService(c *cfg) {
+	endpoint := controlconfig.GRPC(c.appCfg).Endpoint()
+	if endpoint == controlconfig.GRPCEndpointDefault {
+		return
+	}
+
 	pubs := controlconfig.AuthorizedKeys(c.appCfg)
 	rawPubs := make([][]byte, 0, len(pubs)+1) // +1 for node key
 
@@ -38,21 +42,10 @@ func initControlService(c *cfg) {
 		}),
 	)
 
-	var (
-		err      error
-		lis      net.Listener
-		endpoint = controlconfig.GRPC(c.appCfg).Endpoint()
-	)
+	lis, err := net.Listen("tcp", endpoint)
+	fatalOnErr(err)
 
-	if endpoint == "" || endpoint == grpcconfig.Endpoint(c.appCfg) {
-		lis = c.cfgGRPC.listener
-		c.cfgControlService.server = c.cfgGRPC.server
-	} else {
-		lis, err = net.Listen("tcp", endpoint)
-		fatalOnErr(err)
-
-		c.cfgControlService.server = grpc.NewServer()
-	}
+	c.cfgControlService.server = grpc.NewServer()
 
 	c.onShutdown(func() {
 		stopGRPC("NeoFS Control API", c.cfgControlService.server, c.log)