Registration Retry / Interval (#1651)

* Change the default ttl to 90 seconds

* add retries to registration

* Add retry to web register

server/grpc/grpc.go

@@ -22,6 +22,7 @@ import (
 	"github.com/micro/go-micro/v2/registry"
 	"github.com/micro/go-micro/v2/server"
 	"github.com/micro/go-micro/v2/util/addr"
+	"github.com/micro/go-micro/v2/util/backoff"
 	mgrpc "github.com/micro/go-micro/v2/util/grpc"
 	mnet "github.com/micro/go-micro/v2/util/net"
 	"golang.org/x/net/netutil"
@@ -566,16 +567,36 @@ func (g *grpcServer) Subscribe(sb server.Subscriber) error {
 }
 
 func (g *grpcServer) Register() error {
-
 	g.RLock()
 	rsvc := g.rsvc
 	config := g.opts
 	g.RUnlock()
 
+	regFunc := func(service *registry.Service) error {
+		var regErr error
+
+		for i := 0; i < 3; i++ {
+			// set the ttl
+			rOpts := []registry.RegisterOption{registry.RegisterTTL(config.RegisterTTL)}
+			// attempt to register
+			if err := config.Registry.Register(service, rOpts...); err != nil {
+				// set the error
+				regErr = err
+				// backoff then retry
+				time.Sleep(backoff.Do(i + 1))
+				continue
+			}
+			// success so nil error
+			regErr = nil
+			break
+		}
+
+		return regErr
+	}
+
 	// if service already filled, reuse it and return early
 	if rsvc != nil {
-		rOpts := []registry.RegisterOption{registry.RegisterTTL(config.RegisterTTL)}
+		if err := regFunc(rsvc); err != nil {
-		if err := config.Registry.Register(rsvc, rOpts...); err != nil {
 			return err
 		}
 		return nil
@@ -677,10 +698,8 @@ func (g *grpcServer) Register() error {
 		}
 	}
 
-	// create registry options
+	// register the service
-	rOpts := []registry.RegisterOption{registry.RegisterTTL(config.RegisterTTL)}
+	if err := regFunc(service); err != nil {
-
-	if err := config.Registry.Register(service, rOpts...); err != nil {
 		return err
 	}
 

server/rpc_server.go

@@ -20,6 +20,7 @@ import (
 	"github.com/micro/go-micro/v2/registry"
 	"github.com/micro/go-micro/v2/transport"
 	"github.com/micro/go-micro/v2/util/addr"
+	"github.com/micro/go-micro/v2/util/backoff"
 	mnet "github.com/micro/go-micro/v2/util/net"
 	"github.com/micro/go-micro/v2/util/socket"
 )
@@ -514,18 +515,39 @@ func (s *rpcServer) Subscribe(sb Subscriber) error {
 }
 
 func (s *rpcServer) Register() error {
-
 	s.RLock()
 	rsvc := s.rsvc
 	config := s.Options()
 	s.RUnlock()
 
-	if rsvc != nil {
+	regFunc := func(service *registry.Service) error {
+		// create registry options
 		rOpts := []registry.RegisterOption{registry.RegisterTTL(config.RegisterTTL)}
-		if err := config.Registry.Register(rsvc, rOpts...); err != nil {
+
-			return err
+		var regErr error
+
+		for i := 0; i < 3; i++ {
+			// attempt to register
+			if err := config.Registry.Register(service, rOpts...); err != nil {
+				// set the error
+				regErr = err
+				// backoff then retry
+				time.Sleep(backoff.Do(i + 1))
+				continue
+			}
+			// success so nil error
+			regErr = nil
+			break
 		}
 
+		return regErr
+	}
+
+	// have we registered before?
+	if rsvc != nil {
+		if err := regFunc(rsvc); err != nil {
+			return err
+		}
 		return nil
 	}
 
@@ -635,10 +657,8 @@ func (s *rpcServer) Register() error {
 		}
 	}
 
-	// create registry options
+	// register the service
-	rOpts := []registry.RegisterOption{registry.RegisterTTL(config.RegisterTTL)}
+	if err := regFunc(service); err != nil {
-
-	if err := config.Registry.Register(service, rOpts...); err != nil {
 		return err
 	}
 

server/server.go

@@ -145,7 +145,7 @@ var (
 	DefaultRouter                  = newRpcRouter()
 	DefaultRegisterCheck           = func(context.Context) error { return nil }
 	DefaultRegisterInterval        = time.Second * 30
-	DefaultRegisterTTL             = time.Minute
+	DefaultRegisterTTL             = time.Second * 90
 
 	// NewServer creates a new server
 	NewServer func(...Option) Server = newRpcServer

web/service.go

@@ -18,6 +18,7 @@ import (
 	"github.com/micro/go-micro/v2/registry"
 	maddr "github.com/micro/go-micro/v2/util/addr"
 	authutil "github.com/micro/go-micro/v2/util/auth"
+	"github.com/micro/go-micro/v2/util/backoff"
 	mhttp "github.com/micro/go-micro/v2/util/http"
 	mnet "github.com/micro/go-micro/v2/util/net"
 	signalutil "github.com/micro/go-micro/v2/util/signal"
@@ -138,7 +139,24 @@ func (s *service) register() error {
 		return err
 	}
 
-	return r.Register(s.srv, registry.RegisterTTL(s.opts.RegisterTTL))
+	var regErr error
+
+	// try three times if necessary
+	for i := 0; i < 3; i++ {
+		// attempt to register
+		if err := r.Register(s.srv, registry.RegisterTTL(s.opts.RegisterTTL)); err != nil {
+			// set the error
+			regErr = err
+			// backoff then retry
+			time.Sleep(backoff.Do(i + 1))
+			continue
+		}
+		// success so nil error
+		regErr = nil
+		break
+	}
+
+	return regErr
 }
 
 func (s *service) deregister() error {

web/web.go

@@ -31,7 +31,7 @@ var (
 	DefaultAddress = ":0"
 
 	// for registration
-	DefaultRegisterTTL      = time.Minute
+	DefaultRegisterTTL      = time.Second * 90
 	DefaultRegisterInterval = time.Second * 30
 
 	// static directory