vendor: update swarmkit to 6478bc1

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

hack/vendor.sh

@@ -139,7 +139,7 @@ clone git github.com/docker/docker-credential-helpers v0.3.0
 clone git github.com/docker/containerd 1b3a81545ca79456086dc2aa424357be98b962ee
 
 # cluster
-clone git github.com/docker/swarmkit 16fa595d3b6fec012830179dc8e9b2d90335527d
+clone git github.com/docker/swarmkit 6478bc19cf4bc1d7ba2d6f04ccaacf099508f4a0
 clone git github.com/golang/mock bd3c8e81be01eef76d4b503f5e687d2d1354d2d9
 clone git github.com/gogo/protobuf 43a2e0b1c32252bfbbdf81f7faa7a88fb3fa4028
 clone git github.com/cloudflare/cfssl b895b0549c0ff676f92cf09ba971ae02bb41367b

vendor/src/github.com/docker/swarmkit/agent/agent.go

@@ -197,6 +197,11 @@ func (a *Agent) run(ctx context.Context) {
 			sessionq = nil
 			// if we're here before <-registered, do nothing for that event
 			registered = nil
+
+			// Bounce the connection.
+			if a.config.Picker != nil {
+				a.config.Picker.Reset()
+			}
 		case <-session.closed:
 			log.G(ctx).Debugf("agent: rebuild session")
 

vendor/src/github.com/docker/swarmkit/agent/config.go

@@ -19,9 +19,15 @@ type Config struct {
 	// updated with managers weights as observed by the agent.
 	Managers picker.Remotes
 
-	// Conn specifies the client connection Agent will use
+	// Conn specifies the client connection Agent will use.
 	Conn *grpc.ClientConn
 
+	// Picker is the picker used by Conn.
+	// TODO(aaronl): This is only part of the config to allow resetting the
+	// GRPC connection. This should be refactored to address the coupling
+	// between Conn and Picker.
+	Picker *picker.Picker
+
 	// Executor specifies the executor to use for the agent.
 	Executor exec.Executor
 

vendor/src/github.com/docker/swarmkit/agent/node.go

@@ -375,8 +375,9 @@ func (n *Node) runAgent(ctx context.Context, db *bolt.DB, creds credentials.Tran
 	if ctx.Err() != nil {
 		return ctx.Err()
 	}
+	picker := picker.NewPicker(n.remotes, manager.Addr)
 	conn, err := grpc.Dial(manager.Addr,
-		grpc.WithPicker(picker.NewPicker(n.remotes, manager.Addr)),
+		grpc.WithPicker(picker),
 		grpc.WithTransportCredentials(creds),
 		grpc.WithBackoffMaxDelay(maxSessionFailureBackoff))
 	if err != nil {
@@ -389,6 +390,7 @@ func (n *Node) runAgent(ctx context.Context, db *bolt.DB, creds credentials.Tran
 		Executor:         n.config.Executor,
 		DB:               db,
 		Conn:             conn,
+		Picker:           picker,
 		NotifyRoleChange: n.roleChangeReq,
 	})
 	if err != nil {

vendor/src/github.com/docker/swarmkit/agent/session.go

@@ -12,6 +12,8 @@ import (
 	"google.golang.org/grpc/codes"
 )
 
+const dispatcherRPCTimeout = 5 * time.Second
+
 var (
 	errSessionDisconnect = errors.New("agent: session disconnect") // instructed to disconnect
 	errSessionClosed     = errors.New("agent: session closed")
@@ -88,16 +90,39 @@ func (s *session) start(ctx context.Context) error {
 		description.Hostname = s.agent.config.Hostname
 	}
 
-	stream, err := client.Session(ctx, &api.SessionRequest{
-		Description: description,
-	})
-	if err != nil {
-		return err
-	}
+	errChan := make(chan error, 1)
+	var (
+		msg    *api.SessionMessage
+		stream api.Dispatcher_SessionClient
+	)
+	// Note: we don't defer cancellation of this context, because the
+	// streaming RPC is used after this function returned. We only cancel
+	// it in the timeout case to make sure the goroutine completes.
+	sessionCtx, cancelSession := context.WithCancel(ctx)
+
+	// Need to run Session in a goroutine since there's no way to set a
+	// timeout for an individual Recv call in a stream.
+	go func() {
+		stream, err = client.Session(sessionCtx, &api.SessionRequest{
+			Description: description,
+		})
+		if err != nil {
+			errChan <- err
+			return
+		}
 
-	msg, err := stream.Recv()
-	if err != nil {
-		return err
+		msg, err = stream.Recv()
+		errChan <- err
+	}()
+
+	select {
+	case err := <-errChan:
+		if err != nil {
+			return err
+		}
+	case <-time.After(dispatcherRPCTimeout):
+		cancelSession()
+		return errors.New("session initiation timed out")
 	}
 
 	s.sessionID = msg.SessionID
@@ -115,9 +140,11 @@ func (s *session) heartbeat(ctx context.Context) error {
 	for {
 		select {
 		case <-heartbeat.C:
-			resp, err := client.Heartbeat(ctx, &api.HeartbeatRequest{
+			heartbeatCtx, cancel := context.WithTimeout(ctx, dispatcherRPCTimeout)
+			resp, err := client.Heartbeat(heartbeatCtx, &api.HeartbeatRequest{
 				SessionID: s.sessionID,
 			})
+			cancel()
 			if err != nil {
 				if grpc.Code(err) == codes.NotFound {
 					err = errNodeNotRegistered