diff --git a/Gopkg.lock b/Gopkg.lock
index c43bce644ed..c31fe531e10 100644
--- a/Gopkg.lock
+++ b/Gopkg.lock
@@ -1369,7 +1369,7 @@
   revision = "67d6565462c5a0d99b88193d59fefa10ca7e3010"
 
 [[projects]]
-  digest = "1:b1a4f30a5884a325f07d2c650f6df1a9de80554e647372bd1422bf641cffe37f"
+  digest = "1:34a4668b08825463bd30a42862cea31c16371d1e6e95532d255d1e3461ad0545"
   name = "google.golang.org/grpc"
   packages = [
     ".",
@@ -1389,6 +1389,7 @@
     "health/grpc_health_v1",
     "internal",
     "internal/backoff",
+    "internal/balancerload",
     "internal/binarylog",
     "internal/channelz",
     "internal/envconfig",
@@ -1411,8 +1412,8 @@
     "test/bufconn",
   ]
   pruneopts = "NUT"
-  revision = "2fdaae294f38ed9a121193c51ec99fecd3b13eb7"
-  version = "v1.19.0"
+  revision = "25c4f928eaa6d96443009bd842389fb4fa48664e"
+  version = "v1.20.1"
 
 [[projects]]
   digest = "1:aea6e9483c167cc6fdf1274c442558c5dda8fd3373372be04d98c79100868da1"
diff --git a/Gopkg.toml b/Gopkg.toml
index 58a7d650c92..5a415d76083 100644
--- a/Gopkg.toml
+++ b/Gopkg.toml
@@ -83,7 +83,7 @@ required = [
 
 [[constraint]]
   name = "google.golang.org/grpc"
-  version = "1.19.0"
+  version = "1.20.1"
 
 [[constraint]]
   name = "github.com/dexidp/dex"
diff --git a/vendor/google.golang.org/grpc/balancer/balancer.go b/vendor/google.golang.org/grpc/balancer/balancer.go
index 67518de9a1c..fafede238c1 100644
--- a/vendor/google.golang.org/grpc/balancer/balancer.go
+++ b/vendor/google.golang.org/grpc/balancer/balancer.go
@@ -171,9 +171,6 @@ type PickOptions struct {
 	// FullMethodName is the method name that NewClientStream() is called
 	// with. The canonical format is /service/Method.
 	FullMethodName string
-	// Header contains the metadata from the RPC's client header.  The metadata
-	// should not be modified; make a copy first if needed.
-	Header metadata.MD
 }
 
 // DoneInfo contains additional information for done.
@@ -186,6 +183,11 @@ type DoneInfo struct {
 	BytesSent bool
 	// BytesReceived indicates if any byte has been received from the server.
 	BytesReceived bool
+	// ServerLoad is the load received from server. It's usually sent as part of
+	// trailing metadata.
+	//
+	// The only supported type now is *orca_v1.LoadReport.
+	ServerLoad interface{}
 }
 
 var (
@@ -215,8 +217,10 @@ type Picker interface {
 	//
 	// If a SubConn is returned:
 	// - If it is READY, gRPC will send the RPC on it;
-	// - If it is not ready, or becomes not ready after it's returned, gRPC will block
-	//   until UpdateBalancerState() is called and will call pick on the new picker.
+	// - If it is not ready, or becomes not ready after it's returned, gRPC will
+	//   block until UpdateBalancerState() is called and will call pick on the
+	//   new picker. The done function returned from Pick(), if not nil, will be
+	//   called with nil error, no bytes sent and no bytes received.
 	//
 	// If the returned error is not nil:
 	// - If the error is ErrNoSubConnAvailable, gRPC will block until UpdateBalancerState()
@@ -249,18 +253,46 @@ type Balancer interface {
 	// that back to gRPC.
 	// Balancer should also generate and update Pickers when its internal state has
 	// been changed by the new state.
+	//
+	// Deprecated: if V2Balancer is implemented by the Balancer,
+	// UpdateSubConnState will be called instead.
 	HandleSubConnStateChange(sc SubConn, state connectivity.State)
 	// HandleResolvedAddrs is called by gRPC to send updated resolved addresses to
 	// balancers.
 	// Balancer can create new SubConn or remove SubConn with the addresses.
 	// An empty address slice and a non-nil error will be passed if the resolver returns
 	// non-nil error to gRPC.
+	//
+	// Deprecated: if V2Balancer is implemented by the Balancer,
+	// UpdateResolverState will be called instead.
 	HandleResolvedAddrs([]resolver.Address, error)
 	// Close closes the balancer. The balancer is not required to call
 	// ClientConn.RemoveSubConn for its existing SubConns.
 	Close()
 }
 
+// SubConnState describes the state of a SubConn.
+type SubConnState struct {
+	ConnectivityState connectivity.State
+	// TODO: add last connection error
+}
+
+// V2Balancer is defined for documentation purposes.  If a Balancer also
+// implements V2Balancer, its UpdateResolverState method will be called instead
+// of HandleResolvedAddrs and its UpdateSubConnState will be called instead of
+// HandleSubConnStateChange.
+type V2Balancer interface {
+	// UpdateResolverState is called by gRPC when the state of the resolver
+	// changes.
+	UpdateResolverState(resolver.State)
+	// UpdateSubConnState is called by gRPC when the state of a SubConn
+	// changes.
+	UpdateSubConnState(SubConn, SubConnState)
+	// Close closes the balancer. The balancer is not required to call
+	// ClientConn.RemoveSubConn for its existing SubConns.
+	Close()
+}
+
 // ConnectivityStateEvaluator takes the connectivity states of multiple SubConns
 // and returns one aggregated connectivity state.
 //
diff --git a/vendor/google.golang.org/grpc/balancer/base/balancer.go b/vendor/google.golang.org/grpc/balancer/base/balancer.go
index 245785e7a29..c5a51bd1d99 100644
--- a/vendor/google.golang.org/grpc/balancer/base/balancer.go
+++ b/vendor/google.golang.org/grpc/balancer/base/balancer.go
@@ -67,14 +67,16 @@ type baseBalancer struct {
 }
 
 func (b *baseBalancer) HandleResolvedAddrs(addrs []resolver.Address, err error) {
-	if err != nil {
-		grpclog.Infof("base.baseBalancer: HandleResolvedAddrs called with error %v", err)
-		return
-	}
-	grpclog.Infoln("base.baseBalancer: got new resolved addresses: ", addrs)
+	panic("not implemented")
+}
+
+func (b *baseBalancer) UpdateResolverState(s resolver.State) {
+	// TODO: handle s.Err (log if not nil) once implemented.
+	// TODO: handle s.ServiceConfig?
+	grpclog.Infoln("base.baseBalancer: got new resolver state: ", s)
 	// addrsSet is the set converted from addrs, it's used for quick lookup of an address.
 	addrsSet := make(map[resolver.Address]struct{})
-	for _, a := range addrs {
+	for _, a := range s.Addresses {
 		addrsSet[a] = struct{}{}
 		if _, ok := b.subConns[a]; !ok {
 			// a is a new address (not existing in b.subConns).
@@ -120,6 +122,11 @@ func (b *baseBalancer) regeneratePicker() {
 }
 
 func (b *baseBalancer) HandleSubConnStateChange(sc balancer.SubConn, s connectivity.State) {
+	panic("not implemented")
+}
+
+func (b *baseBalancer) UpdateSubConnState(sc balancer.SubConn, state balancer.SubConnState) {
+	s := state.ConnectivityState
 	grpclog.Infof("base.baseBalancer: handle SubConn state change: %p, %v", sc, s)
 	oldS, ok := b.scStates[sc]
 	if !ok {
diff --git a/vendor/google.golang.org/grpc/balancer_conn_wrappers.go b/vendor/google.golang.org/grpc/balancer_conn_wrappers.go
index 7233ade293b..bc965f0acaa 100644
--- a/vendor/google.golang.org/grpc/balancer_conn_wrappers.go
+++ b/vendor/google.golang.org/grpc/balancer_conn_wrappers.go
@@ -82,20 +82,13 @@ func (b *scStateUpdateBuffer) get() <-chan *scStateUpdate {
 	return b.c
 }
 
-// resolverUpdate contains the new resolved addresses or error if there's
-// any.
-type resolverUpdate struct {
-	addrs []resolver.Address
-	err   error
-}
-
 // ccBalancerWrapper is a wrapper on top of cc for balancers.
 // It implements balancer.ClientConn interface.
 type ccBalancerWrapper struct {
 	cc               *ClientConn
 	balancer         balancer.Balancer
 	stateChangeQueue *scStateUpdateBuffer
-	resolverUpdateCh chan *resolverUpdate
+	resolverUpdateCh chan *resolver.State
 	done             chan struct{}
 
 	mu       sync.Mutex
@@ -106,7 +99,7 @@ func newCCBalancerWrapper(cc *ClientConn, b balancer.Builder, bopts balancer.Bui
 	ccb := &ccBalancerWrapper{
 		cc:               cc,
 		stateChangeQueue: newSCStateUpdateBuffer(),
-		resolverUpdateCh: make(chan *resolverUpdate, 1),
+		resolverUpdateCh: make(chan *resolver.State, 1),
 		done:             make(chan struct{}),
 		subConns:         make(map[*acBalancerWrapper]struct{}),
 	}
@@ -128,15 +121,23 @@ func (ccb *ccBalancerWrapper) watcher() {
 				return
 			default:
 			}
-			ccb.balancer.HandleSubConnStateChange(t.sc, t.state)
-		case t := <-ccb.resolverUpdateCh:
+			if ub, ok := ccb.balancer.(balancer.V2Balancer); ok {
+				ub.UpdateSubConnState(t.sc, balancer.SubConnState{ConnectivityState: t.state})
+			} else {
+				ccb.balancer.HandleSubConnStateChange(t.sc, t.state)
+			}
+		case s := <-ccb.resolverUpdateCh:
 			select {
 			case <-ccb.done:
 				ccb.balancer.Close()
 				return
 			default:
 			}
-			ccb.balancer.HandleResolvedAddrs(t.addrs, t.err)
+			if ub, ok := ccb.balancer.(balancer.V2Balancer); ok {
+				ub.UpdateResolverState(*s)
+			} else {
+				ccb.balancer.HandleResolvedAddrs(s.Addresses, nil)
+			}
 		case <-ccb.done:
 		}
 
@@ -177,37 +178,23 @@ func (ccb *ccBalancerWrapper) handleSubConnStateChange(sc balancer.SubConn, s co
 	})
 }
 
-func (ccb *ccBalancerWrapper) handleResolvedAddrs(addrs []resolver.Address, err error) {
+func (ccb *ccBalancerWrapper) updateResolverState(s resolver.State) {
 	if ccb.cc.curBalancerName != grpclbName {
-		var containsGRPCLB bool
-		for _, a := range addrs {
-			if a.Type == resolver.GRPCLB {
-				containsGRPCLB = true
-				break
+		// Filter any grpclb addresses since we don't have the grpclb balancer.
+		for i := 0; i < len(s.Addresses); {
+			if s.Addresses[i].Type == resolver.GRPCLB {
+				copy(s.Addresses[i:], s.Addresses[i+1:])
+				s.Addresses = s.Addresses[:len(s.Addresses)-1]
+				continue
 			}
-		}
-		if containsGRPCLB {
-			// The current balancer is not grpclb, but addresses contain grpclb
-			// address. This means we failed to switch to grpclb, most likely
-			// because grpclb is not registered. Filter out all grpclb addresses
-			// from addrs before sending to balancer.
-			tempAddrs := make([]resolver.Address, 0, len(addrs))
-			for _, a := range addrs {
-				if a.Type != resolver.GRPCLB {
-					tempAddrs = append(tempAddrs, a)
-				}
-			}
-			addrs = tempAddrs
+			i++
 		}
 	}
 	select {
 	case <-ccb.resolverUpdateCh:
 	default:
 	}
-	ccb.resolverUpdateCh <- &resolverUpdate{
-		addrs: addrs,
-		err:   err,
-	}
+	ccb.resolverUpdateCh <- &s
 }
 
 func (ccb *ccBalancerWrapper) NewSubConn(addrs []resolver.Address, opts balancer.NewSubConnOptions) (balancer.SubConn, error) {
diff --git a/vendor/google.golang.org/grpc/clientconn.go b/vendor/google.golang.org/grpc/clientconn.go
index edbed8762c1..bd2d2b31779 100644
--- a/vendor/google.golang.org/grpc/clientconn.go
+++ b/vendor/google.golang.org/grpc/clientconn.go
@@ -42,7 +42,6 @@ import (
 	"google.golang.org/grpc/internal/grpcsync"
 	"google.golang.org/grpc/internal/transport"
 	"google.golang.org/grpc/keepalive"
-	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/resolver"
 	_ "google.golang.org/grpc/resolver/dns"         // To register dns resolver.
 	_ "google.golang.org/grpc/resolver/passthrough" // To register passthrough resolver.
@@ -69,11 +68,9 @@ var (
 	errConnClosing = errors.New("grpc: the connection is closing")
 	// errBalancerClosed indicates that the balancer is closed.
 	errBalancerClosed = errors.New("grpc: balancer is closed")
-	// We use an accessor so that minConnectTimeout can be
-	// atomically read and updated while testing.
-	getMinConnectTimeout = func() time.Duration {
-		return minConnectTimeout
-	}
+	// invalidDefaultServiceConfigErrPrefix is used to prefix the json parsing error for the default
+	// service config.
+	invalidDefaultServiceConfigErrPrefix = "grpc: the provided default service config is invalid"
 )
 
 // The following errors are returned from Dial and DialContext
@@ -140,6 +137,12 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		opt.apply(&cc.dopts)
 	}
 
+	defer func() {
+		if err != nil {
+			cc.Close()
+		}
+	}()
+
 	if channelz.IsOn() {
 		if cc.dopts.channelzParentID != 0 {
 			cc.channelzID = channelz.RegisterChannel(&channelzChannel{cc}, cc.dopts.channelzParentID, target)
@@ -179,6 +182,13 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		}
 	}
 
+	if cc.dopts.defaultServiceConfigRawJSON != nil {
+		sc, err := parseServiceConfig(*cc.dopts.defaultServiceConfigRawJSON)
+		if err != nil {
+			return nil, fmt.Errorf("%s: %v", invalidDefaultServiceConfigErrPrefix, err)
+		}
+		cc.dopts.defaultServiceConfig = sc
+	}
 	cc.mkp = cc.dopts.copts.KeepaliveParams
 
 	if cc.dopts.copts.Dialer == nil {
@@ -201,17 +211,12 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		ctx, cancel = context.WithTimeout(ctx, cc.dopts.timeout)
 		defer cancel()
 	}
-
 	defer func() {
 		select {
 		case <-ctx.Done():
 			conn, err = nil, ctx.Err()
 		default:
 		}
-
-		if err != nil {
-			cc.Close()
-		}
 	}()
 
 	scSet := false
@@ -220,7 +225,7 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		select {
 		case sc, ok := <-cc.dopts.scChan:
 			if ok {
-				cc.sc = sc
+				cc.sc = &sc
 				scSet = true
 			}
 		default:
@@ -266,7 +271,7 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		select {
 		case sc, ok := <-cc.dopts.scChan:
 			if ok {
-				cc.sc = sc
+				cc.sc = &sc
 			}
 		case <-ctx.Done():
 			return nil, ctx.Err()
@@ -388,14 +393,11 @@ type ClientConn struct {
 
 	mu              sync.RWMutex
 	resolverWrapper *ccResolverWrapper
-	sc              ServiceConfig
-	scRaw           string
+	sc              *ServiceConfig
 	conns           map[*addrConn]struct{}
 	// Keepalive parameter can be updated if a GoAway is received.
 	mkp             keepalive.ClientParameters
 	curBalancerName string
-	preBalancerName string // previous balancer name.
-	curAddresses    []resolver.Address
 	balancerWrapper *ccBalancerWrapper
 	retryThrottler  atomic.Value
 
@@ -437,8 +439,7 @@ func (cc *ClientConn) scWatcher() {
 			cc.mu.Lock()
 			// TODO: load balance policy runtime change is ignored.
 			// We may revisit this decision in the future.
-			cc.sc = sc
-			cc.scRaw = ""
+			cc.sc = &sc
 			cc.mu.Unlock()
 		case <-cc.ctx.Done():
 			return
@@ -465,50 +466,72 @@ func (cc *ClientConn) waitForResolvedAddrs(ctx context.Context) error {
 	}
 }
 
-func (cc *ClientConn) handleResolvedAddrs(addrs []resolver.Address, err error) {
+// gRPC should resort to default service config when:
+// * resolver service config is disabled
+// * or, resolver does not return a service config or returns an invalid one.
+func (cc *ClientConn) fallbackToDefaultServiceConfig(sc string) bool {
+	if cc.dopts.disableServiceConfig {
+		return true
+	}
+	// The logic below is temporary, will be removed once we change the resolver.State ServiceConfig field type.
+	// Right now, we assume that empty service config string means resolver does not return a config.
+	if sc == "" {
+		return true
+	}
+	// TODO: the logic below is temporary. Once we finish the logic to validate service config
+	// in resolver, we will replace the logic below.
+	_, err := parseServiceConfig(sc)
+	return err != nil
+}
+
+func (cc *ClientConn) updateResolverState(s resolver.State) error {
 	cc.mu.Lock()
 	defer cc.mu.Unlock()
+	// Check if the ClientConn is already closed. Some fields (e.g.
+	// balancerWrapper) are set to nil when closing the ClientConn, and could
+	// cause nil pointer panic if we don't have this check.
 	if cc.conns == nil {
-		// cc was closed.
-		return
+		return nil
 	}
 
-	if reflect.DeepEqual(cc.curAddresses, addrs) {
-		return
+	if cc.fallbackToDefaultServiceConfig(s.ServiceConfig) {
+		if cc.dopts.defaultServiceConfig != nil && cc.sc == nil {
+			cc.applyServiceConfig(cc.dopts.defaultServiceConfig)
+		}
+	} else {
+		// TODO: the parsing logic below will be moved inside resolver.
+		sc, err := parseServiceConfig(s.ServiceConfig)
+		if err != nil {
+			return err
+		}
+		if cc.sc == nil || cc.sc.rawJSONString != s.ServiceConfig {
+			cc.applyServiceConfig(sc)
+		}
 	}
 
-	cc.curAddresses = addrs
-	cc.firstResolveEvent.Fire()
+	// update the service config that will be sent to balancer.
+	if cc.sc != nil {
+		s.ServiceConfig = cc.sc.rawJSONString
+	}
 
 	if cc.dopts.balancerBuilder == nil {
 		// Only look at balancer types and switch balancer if balancer dial
 		// option is not set.
 		var isGRPCLB bool
-		for _, a := range addrs {
+		for _, a := range s.Addresses {
 			if a.Type == resolver.GRPCLB {
 				isGRPCLB = true
 				break
 			}
 		}
 		var newBalancerName string
+		// TODO: use new loadBalancerConfig field with appropriate priority.
 		if isGRPCLB {
 			newBalancerName = grpclbName
+		} else if cc.sc != nil && cc.sc.LB != nil {
+			newBalancerName = *cc.sc.LB
 		} else {
-			// Address list doesn't contain grpclb address. Try to pick a
-			// non-grpclb balancer.
-			newBalancerName = cc.curBalancerName
-			// If current balancer is grpclb, switch to the previous one.
-			if newBalancerName == grpclbName {
-				newBalancerName = cc.preBalancerName
-			}
-			// The following could be true in two cases:
-			// - the first time handling resolved addresses
-			//   (curBalancerName="")
-			// - the first time handling non-grpclb addresses
-			//   (curBalancerName="grpclb", preBalancerName="")
-			if newBalancerName == "" {
-				newBalancerName = PickFirstBalancerName
-			}
+			newBalancerName = PickFirstBalancerName
 		}
 		cc.switchBalancer(newBalancerName)
 	} else if cc.balancerWrapper == nil {
@@ -517,7 +540,9 @@ func (cc *ClientConn) handleResolvedAddrs(addrs []resolver.Address, err error) {
 		cc.balancerWrapper = newCCBalancerWrapper(cc, cc.dopts.balancerBuilder, cc.balancerBuildOpts)
 	}
 
-	cc.balancerWrapper.handleResolvedAddrs(addrs, nil)
+	cc.balancerWrapper.updateResolverState(s)
+	cc.firstResolveEvent.Fire()
+	return nil
 }
 
 // switchBalancer starts the switching from current balancer to the balancer
@@ -529,10 +554,6 @@ func (cc *ClientConn) handleResolvedAddrs(addrs []resolver.Address, err error) {
 //
 // Caller must hold cc.mu.
 func (cc *ClientConn) switchBalancer(name string) {
-	if cc.conns == nil {
-		return
-	}
-
 	if strings.ToLower(cc.curBalancerName) == strings.ToLower(name) {
 		return
 	}
@@ -542,15 +563,11 @@ func (cc *ClientConn) switchBalancer(name string) {
 		grpclog.Infoln("ignoring balancer switching: Balancer DialOption used instead")
 		return
 	}
-	// TODO(bar switching) change this to two steps: drain and close.
-	// Keep track of sc in wrapper.
 	if cc.balancerWrapper != nil {
 		cc.balancerWrapper.close()
 	}
 
 	builder := balancer.Get(name)
-	// TODO(yuxuanli): If user send a service config that does not contain a valid balancer name, should
-	// we reuse previous one?
 	if channelz.IsOn() {
 		if builder == nil {
 			channelz.AddTraceEvent(cc.channelzID, &channelz.TraceEventDesc{
@@ -569,7 +586,6 @@ func (cc *ClientConn) switchBalancer(name string) {
 		builder = newPickfirstBuilder()
 	}
 
-	cc.preBalancerName = cc.curBalancerName
 	cc.curBalancerName = builder.Name()
 	cc.balancerWrapper = newCCBalancerWrapper(cc, builder, cc.balancerBuildOpts)
 }
@@ -732,6 +748,9 @@ func (cc *ClientConn) GetMethodConfig(method string) MethodConfig {
 	// TODO: Avoid the locking here.
 	cc.mu.RLock()
 	defer cc.mu.RUnlock()
+	if cc.sc == nil {
+		return MethodConfig{}
+	}
 	m, ok := cc.sc.Methods[method]
 	if !ok {
 		i := strings.LastIndex(method, "/")
@@ -743,14 +762,15 @@ func (cc *ClientConn) GetMethodConfig(method string) MethodConfig {
 func (cc *ClientConn) healthCheckConfig() *healthCheckConfig {
 	cc.mu.RLock()
 	defer cc.mu.RUnlock()
+	if cc.sc == nil {
+		return nil
+	}
 	return cc.sc.healthCheckConfig
 }
 
 func (cc *ClientConn) getTransport(ctx context.Context, failfast bool, method string) (transport.ClientTransport, func(balancer.DoneInfo), error) {
-	hdr, _ := metadata.FromOutgoingContext(ctx)
 	t, done, err := cc.blockingpicker.pick(ctx, failfast, balancer.PickOptions{
 		FullMethodName: method,
-		Header:         hdr,
 	})
 	if err != nil {
 		return nil, nil, toRPCErr(err)
@@ -758,65 +778,25 @@ func (cc *ClientConn) getTransport(ctx context.Context, failfast bool, method st
 	return t, done, nil
 }
 
-// handleServiceConfig parses the service config string in JSON format to Go native
-// struct ServiceConfig, and store both the struct and the JSON string in ClientConn.
-func (cc *ClientConn) handleServiceConfig(js string) error {
-	if cc.dopts.disableServiceConfig {
-		return nil
-	}
-	if cc.scRaw == js {
-		return nil
-	}
-	if channelz.IsOn() {
-		channelz.AddTraceEvent(cc.channelzID, &channelz.TraceEventDesc{
-			// The special formatting of \"%s\" instead of %q is to provide nice printing of service config
-			// for human consumption.
-			Desc:     fmt.Sprintf("Channel has a new service config \"%s\"", js),
-			Severity: channelz.CtINFO,
-		})
-	}
-	sc, err := parseServiceConfig(js)
-	if err != nil {
-		return err
+func (cc *ClientConn) applyServiceConfig(sc *ServiceConfig) error {
+	if sc == nil {
+		// should never reach here.
+		return fmt.Errorf("got nil pointer for service config")
 	}
-	cc.mu.Lock()
-	// Check if the ClientConn is already closed. Some fields (e.g.
-	// balancerWrapper) are set to nil when closing the ClientConn, and could
-	// cause nil pointer panic if we don't have this check.
-	if cc.conns == nil {
-		cc.mu.Unlock()
-		return nil
-	}
-	cc.scRaw = js
 	cc.sc = sc
 
-	if sc.retryThrottling != nil {
+	if cc.sc.retryThrottling != nil {
 		newThrottler := &retryThrottler{
-			tokens: sc.retryThrottling.MaxTokens,
-			max:    sc.retryThrottling.MaxTokens,
-			thresh: sc.retryThrottling.MaxTokens / 2,
-			ratio:  sc.retryThrottling.TokenRatio,
+			tokens: cc.sc.retryThrottling.MaxTokens,
+			max:    cc.sc.retryThrottling.MaxTokens,
+			thresh: cc.sc.retryThrottling.MaxTokens / 2,
+			ratio:  cc.sc.retryThrottling.TokenRatio,
 		}
 		cc.retryThrottler.Store(newThrottler)
 	} else {
 		cc.retryThrottler.Store((*retryThrottler)(nil))
 	}
 
-	if sc.LB != nil && *sc.LB != grpclbName { // "grpclb" is not a valid balancer option in service config.
-		if cc.curBalancerName == grpclbName {
-			// If current balancer is grpclb, there's at least one grpclb
-			// balancer address in the resolved list. Don't switch the balancer,
-			// but change the previous balancer name, so if a new resolved
-			// address list doesn't contain grpclb address, balancer will be
-			// switched to *sc.LB.
-			cc.preBalancerName = *sc.LB
-		} else {
-			cc.switchBalancer(*sc.LB)
-			cc.balancerWrapper.handleResolvedAddrs(cc.curAddresses, nil)
-		}
-	}
-
-	cc.mu.Unlock()
 	return nil
 }
 
@@ -892,7 +872,7 @@ func (cc *ClientConn) Close() error {
 		}
 		channelz.AddTraceEvent(cc.channelzID, ted)
 		// TraceEvent needs to be called before RemoveEntry, as TraceEvent may add trace reference to
-		// the entity beng deleted, and thus prevent it from being deleted right away.
+		// the entity being deleted, and thus prevent it from being deleted right away.
 		channelz.RemoveEntry(cc.channelzID)
 	}
 	return nil
@@ -921,8 +901,6 @@ type addrConn struct {
 	// Use updateConnectivityState for updating addrConn's connectivity state.
 	state connectivity.State
 
-	tearDownErr error // The reason this addrConn is torn down.
-
 	backoffIdx   int // Needs to be stateful for resetConnectBackoff.
 	resetBackoff chan struct{}
 
@@ -963,190 +941,169 @@ func (ac *addrConn) adjustParams(r transport.GoAwayReason) {
 
 func (ac *addrConn) resetTransport() {
 	for i := 0; ; i++ {
-		tryNextAddrFromStart := grpcsync.NewEvent()
-
-		ac.mu.Lock()
 		if i > 0 {
 			ac.cc.resolveNow(resolver.ResolveNowOption{})
 		}
+
+		ac.mu.Lock()
+		if ac.state == connectivity.Shutdown {
+			ac.mu.Unlock()
+			return
+		}
+
 		addrs := ac.addrs
 		backoffFor := ac.dopts.bs.Backoff(ac.backoffIdx)
-
 		// This will be the duration that dial gets to finish.
-		dialDuration := getMinConnectTimeout()
+		dialDuration := minConnectTimeout
+		if ac.dopts.minConnectTimeout != nil {
+			dialDuration = ac.dopts.minConnectTimeout()
+		}
+
 		if dialDuration < backoffFor {
 			// Give dial more time as we keep failing to connect.
 			dialDuration = backoffFor
 		}
+		// We can potentially spend all the time trying the first address, and
+		// if the server accepts the connection and then hangs, the following
+		// addresses will never be tried.
+		//
+		// The spec doesn't mention what should be done for multiple addresses.
+		// https://github.com/grpc/grpc/blob/master/doc/connection-backoff.md#proposed-backoff-algorithm
 		connectDeadline := time.Now().Add(dialDuration)
 		ac.mu.Unlock()
 
-	addrLoop:
-		for _, addr := range addrs {
+		newTr, addr, reconnect, err := ac.tryAllAddrs(addrs, connectDeadline)
+		if err != nil {
+			// After exhausting all addresses, the addrConn enters
+			// TRANSIENT_FAILURE.
 			ac.mu.Lock()
-
-			if ac.state == connectivity.Shutdown {
-				ac.mu.Unlock()
-				return
-			}
-			ac.updateConnectivityState(connectivity.Connecting)
-			ac.transport = nil
-
-			ac.cc.mu.RLock()
-			ac.dopts.copts.KeepaliveParams = ac.cc.mkp
-			ac.cc.mu.RUnlock()
-
 			if ac.state == connectivity.Shutdown {
 				ac.mu.Unlock()
 				return
 			}
+			ac.updateConnectivityState(connectivity.TransientFailure)
 
-			copts := ac.dopts.copts
-			if ac.scopts.CredsBundle != nil {
-				copts.CredsBundle = ac.scopts.CredsBundle
-			}
-			hctx, hcancel := context.WithCancel(ac.ctx)
-			defer hcancel()
+			// Backoff.
+			b := ac.resetBackoff
 			ac.mu.Unlock()
 
-			if channelz.IsOn() {
-				channelz.AddTraceEvent(ac.channelzID, &channelz.TraceEventDesc{
-					Desc:     fmt.Sprintf("Subchannel picks a new address %q to connect", addr.Addr),
-					Severity: channelz.CtINFO,
-				})
-			}
-
-			reconnect := grpcsync.NewEvent()
-			prefaceReceived := make(chan struct{})
-			newTr, err := ac.createTransport(addr, copts, connectDeadline, reconnect, prefaceReceived)
-			if err == nil {
+			timer := time.NewTimer(backoffFor)
+			select {
+			case <-timer.C:
 				ac.mu.Lock()
-				ac.curAddr = addr
-				ac.transport = newTr
+				ac.backoffIdx++
 				ac.mu.Unlock()
-
-				healthCheckConfig := ac.cc.healthCheckConfig()
-				// LB channel health checking is only enabled when all the four requirements below are met:
-				// 1. it is not disabled by the user with the WithDisableHealthCheck DialOption,
-				// 2. the internal.HealthCheckFunc is set by importing the grpc/healthcheck package,
-				// 3. a service config with non-empty healthCheckConfig field is provided,
-				// 4. the current load balancer allows it.
-				healthcheckManagingState := false
-				if !ac.cc.dopts.disableHealthCheck && healthCheckConfig != nil && ac.scopts.HealthCheckEnabled {
-					if ac.cc.dopts.healthCheckFunc == nil {
-						// TODO: add a link to the health check doc in the error message.
-						grpclog.Error("the client side LB channel health check function has not been set.")
-					} else {
-						// TODO(deklerk) refactor to just return transport
-						go ac.startHealthCheck(hctx, newTr, addr, healthCheckConfig.ServiceName)
-						healthcheckManagingState = true
-					}
-				}
-				if !healthcheckManagingState {
-					ac.mu.Lock()
-					ac.updateConnectivityState(connectivity.Ready)
-					ac.mu.Unlock()
-				}
-			} else {
-				hcancel()
-				if err == errConnClosing {
-					return
-				}
-
-				if tryNextAddrFromStart.HasFired() {
-					break addrLoop
-				}
-				continue
+			case <-b:
+				timer.Stop()
+			case <-ac.ctx.Done():
+				timer.Stop()
+				return
 			}
+			continue
+		}
 
-			ac.mu.Lock()
-			reqHandshake := ac.dopts.reqHandshake
+		ac.mu.Lock()
+		if ac.state == connectivity.Shutdown {
+			newTr.Close()
 			ac.mu.Unlock()
-
-			<-reconnect.Done()
-			hcancel()
-
-			if reqHandshake == envconfig.RequireHandshakeHybrid {
-				// In RequireHandshakeHybrid mode, we must check to see whether
-				// server preface has arrived yet to decide whether to start
-				// reconnecting at the top of the list (server preface received)
-				// or continue with the next addr in the list as if the
-				// connection were not successful (server preface not received).
-				select {
-				case <-prefaceReceived:
-					// We received a server preface - huzzah! We consider this
-					// a success and restart from the top of the addr list.
-					ac.mu.Lock()
-					ac.backoffIdx = 0
-					ac.mu.Unlock()
-					break addrLoop
-				default:
-					// Despite having set state to READY, in hybrid mode we
-					// consider this a failure and continue connecting at the
-					// next addr in the list.
-					ac.mu.Lock()
-					if ac.state == connectivity.Shutdown {
-						ac.mu.Unlock()
-						return
-					}
-
-					ac.updateConnectivityState(connectivity.TransientFailure)
-					ac.mu.Unlock()
-
-					if tryNextAddrFromStart.HasFired() {
-						break addrLoop
-					}
-				}
+			return
+		}
+		ac.curAddr = addr
+		ac.transport = newTr
+		ac.backoffIdx = 0
+
+		healthCheckConfig := ac.cc.healthCheckConfig()
+		// LB channel health checking is only enabled when all the four requirements below are met:
+		// 1. it is not disabled by the user with the WithDisableHealthCheck DialOption,
+		// 2. the internal.HealthCheckFunc is set by importing the grpc/healthcheck package,
+		// 3. a service config with non-empty healthCheckConfig field is provided,
+		// 4. the current load balancer allows it.
+		hctx, hcancel := context.WithCancel(ac.ctx)
+		healthcheckManagingState := false
+		if !ac.cc.dopts.disableHealthCheck && healthCheckConfig != nil && ac.scopts.HealthCheckEnabled {
+			if ac.cc.dopts.healthCheckFunc == nil {
+				// TODO: add a link to the health check doc in the error message.
+				grpclog.Error("the client side LB channel health check function has not been set.")
 			} else {
-				// In RequireHandshakeOn mode, we would have already waited for
-				// the server preface, so we consider this a success and restart
-				// from the top of the addr list. In RequireHandshakeOff mode,
-				// we don't care to wait for the server preface before
-				// considering this a success, so we also restart from the top
-				// of the addr list.
-				ac.mu.Lock()
-				ac.backoffIdx = 0
-				ac.mu.Unlock()
-				break addrLoop
+				// TODO(deklerk) refactor to just return transport
+				go ac.startHealthCheck(hctx, newTr, addr, healthCheckConfig.ServiceName)
+				healthcheckManagingState = true
 			}
 		}
+		if !healthcheckManagingState {
+			ac.updateConnectivityState(connectivity.Ready)
+		}
+		ac.mu.Unlock()
 
-		// After exhausting all addresses, or after need to reconnect after a
-		// READY, the addrConn enters TRANSIENT_FAILURE.
+		// Block until the created transport is down. And when this happens,
+		// we restart from the top of the addr list.
+		<-reconnect.Done()
+		hcancel()
+
+		// Need to reconnect after a READY, the addrConn enters
+		// TRANSIENT_FAILURE.
+		//
+		// This will set addrConn to TRANSIENT_FAILURE for a very short period
+		// of time, and turns CONNECTING. It seems reasonable to skip this, but
+		// READY-CONNECTING is not a valid transition.
 		ac.mu.Lock()
 		if ac.state == connectivity.Shutdown {
 			ac.mu.Unlock()
 			return
 		}
 		ac.updateConnectivityState(connectivity.TransientFailure)
-
-		// Backoff.
-		b := ac.resetBackoff
-		timer := time.NewTimer(backoffFor)
-		acctx := ac.ctx
 		ac.mu.Unlock()
+	}
+}
 
-		select {
-		case <-timer.C:
-			ac.mu.Lock()
-			ac.backoffIdx++
+// tryAllAddrs tries to creates a connection to the addresses, and stop when at the
+// first successful one. It returns the transport, the address and a Event in
+// the successful case. The Event fires when the returned transport disconnects.
+func (ac *addrConn) tryAllAddrs(addrs []resolver.Address, connectDeadline time.Time) (transport.ClientTransport, resolver.Address, *grpcsync.Event, error) {
+	for _, addr := range addrs {
+		ac.mu.Lock()
+		if ac.state == connectivity.Shutdown {
 			ac.mu.Unlock()
-		case <-b:
-			timer.Stop()
-		case <-acctx.Done():
-			timer.Stop()
-			return
+			return nil, resolver.Address{}, nil, errConnClosing
+		}
+		ac.updateConnectivityState(connectivity.Connecting)
+		ac.transport = nil
+
+		ac.cc.mu.RLock()
+		ac.dopts.copts.KeepaliveParams = ac.cc.mkp
+		ac.cc.mu.RUnlock()
+
+		copts := ac.dopts.copts
+		if ac.scopts.CredsBundle != nil {
+			copts.CredsBundle = ac.scopts.CredsBundle
+		}
+		ac.mu.Unlock()
+
+		if channelz.IsOn() {
+			channelz.AddTraceEvent(ac.channelzID, &channelz.TraceEventDesc{
+				Desc:     fmt.Sprintf("Subchannel picks a new address %q to connect", addr.Addr),
+				Severity: channelz.CtINFO,
+			})
 		}
+
+		newTr, reconnect, err := ac.createTransport(addr, copts, connectDeadline)
+		if err == nil {
+			return newTr, addr, reconnect, nil
+		}
+		ac.cc.blockingpicker.updateConnectionError(err)
 	}
+
+	// Couldn't connect to any address.
+	return nil, resolver.Address{}, nil, fmt.Errorf("couldn't connect to any address")
 }
 
-// createTransport creates a connection to one of the backends in addrs. It
-// sets ac.transport in the success case, or it returns an error if it was
-// unable to successfully create a transport.
-//
-// If waitForHandshake is enabled, it blocks until server preface arrives.
-func (ac *addrConn) createTransport(addr resolver.Address, copts transport.ConnectOptions, connectDeadline time.Time, reconnect *grpcsync.Event, prefaceReceived chan struct{}) (transport.ClientTransport, error) {
+// createTransport creates a connection to addr. It returns the transport and a
+// Event in the successful case. The Event fires when the returned transport
+// disconnects.
+func (ac *addrConn) createTransport(addr resolver.Address, copts transport.ConnectOptions, connectDeadline time.Time) (transport.ClientTransport, *grpcsync.Event, error) {
+	prefaceReceived := make(chan struct{})
 	onCloseCalled := make(chan struct{})
+	reconnect := grpcsync.NewEvent()
 
 	target := transport.TargetInfo{
 		Addr:      addr.Addr,
@@ -1154,8 +1111,6 @@ func (ac *addrConn) createTransport(addr resolver.Address, copts transport.Conne
 		Authority: ac.cc.authority,
 	}
 
-	prefaceTimer := time.NewTimer(time.Until(connectDeadline))
-
 	onGoAway := func(r transport.GoAwayReason) {
 		ac.mu.Lock()
 		ac.adjustParams(r)
@@ -1165,13 +1120,11 @@ func (ac *addrConn) createTransport(addr resolver.Address, copts transport.Conne
 
 	onClose := func() {
 		close(onCloseCalled)
-		prefaceTimer.Stop()
 		reconnect.Fire()
 	}
 
 	onPrefaceReceipt := func() {
 		close(prefaceReceived)
-		prefaceTimer.Stop()
 	}
 
 	connectCtx, cancel := context.WithDeadline(ac.ctx, connectDeadline)
@@ -1181,69 +1134,28 @@ func (ac *addrConn) createTransport(addr resolver.Address, copts transport.Conne
 	}
 
 	newTr, err := transport.NewClientTransport(connectCtx, ac.cc.ctx, target, copts, onPrefaceReceipt, onGoAway, onClose)
-
-	if err == nil {
-		if ac.dopts.reqHandshake == envconfig.RequireHandshakeOn {
-			select {
-			case <-prefaceTimer.C:
-				// We didn't get the preface in time.
-				newTr.Close()
-				err = errors.New("timed out waiting for server handshake")
-			case <-prefaceReceived:
-				// We got the preface - huzzah! things are good.
-			case <-onCloseCalled:
-				// The transport has already closed - noop.
-				return nil, errors.New("connection closed")
-			}
-		} else if ac.dopts.reqHandshake == envconfig.RequireHandshakeHybrid {
-			go func() {
-				select {
-				case <-prefaceTimer.C:
-					// We didn't get the preface in time.
-					newTr.Close()
-				case <-prefaceReceived:
-					// We got the preface just in the nick of time - huzzah!
-				case <-onCloseCalled:
-					// The transport has already closed - noop.
-				}
-			}()
-		}
-	}
-
 	if err != nil {
 		// newTr is either nil, or closed.
-		ac.cc.blockingpicker.updateConnectionError(err)
-		ac.mu.Lock()
-		if ac.state == connectivity.Shutdown {
-			// ac.tearDown(...) has been invoked.
-			ac.mu.Unlock()
-
-			return nil, errConnClosing
-		}
-		ac.mu.Unlock()
 		grpclog.Warningf("grpc: addrConn.createTransport failed to connect to %v. Err :%v. Reconnecting...", addr, err)
-		return nil, err
-	}
-
-	// Now there is a viable transport to be use, so set ac.transport to reflect the new viable transport.
-	ac.mu.Lock()
-	if ac.state == connectivity.Shutdown {
-		ac.mu.Unlock()
-		newTr.Close()
-		return nil, errConnClosing
+		return nil, nil, err
 	}
-	ac.mu.Unlock()
 
-	// Now there is a viable transport to be use, so set ac.transport to reflect the new viable transport.
-	ac.mu.Lock()
-	if ac.state == connectivity.Shutdown {
-		ac.mu.Unlock()
-		newTr.Close()
-		return nil, errConnClosing
+	if ac.dopts.reqHandshake == envconfig.RequireHandshakeOn {
+		select {
+		case <-time.After(connectDeadline.Sub(time.Now())):
+			// We didn't get the preface in time.
+			newTr.Close()
+			grpclog.Warningf("grpc: addrConn.createTransport failed to connect to %v: didn't receive server preface in time. Reconnecting...", addr)
+			return nil, nil, errors.New("timed out waiting for server handshake")
+		case <-prefaceReceived:
+			// We got the preface - huzzah! things are good.
+		case <-onCloseCalled:
+			// The transport has already closed - noop.
+			return nil, nil, errors.New("connection closed")
+			// TODO(deklerk) this should bail on ac.ctx.Done(). Add a test and fix.
+		}
 	}
-	ac.mu.Unlock()
-
-	return newTr, nil
+	return newTr, reconnect, nil
 }
 
 func (ac *addrConn) startHealthCheck(ctx context.Context, newTr transport.ClientTransport, addr resolver.Address, serviceName string) {
@@ -1331,7 +1243,6 @@ func (ac *addrConn) tearDown(err error) {
 	// between setting the state and logic that waits on context cancelation / etc.
 	ac.updateConnectivityState(connectivity.Shutdown)
 	ac.cancel()
-	ac.tearDownErr = err
 	ac.curAddr = resolver.Address{}
 	if err == errConnDrain && curTr != nil {
 		// GracefulClose(...) may be executed multiple times when
diff --git a/vendor/google.golang.org/grpc/credentials/credentials.go b/vendor/google.golang.org/grpc/credentials/credentials.go
index a851560456b..88aff94596a 100644
--- a/vendor/google.golang.org/grpc/credentials/credentials.go
+++ b/vendor/google.golang.org/grpc/credentials/credentials.go
@@ -36,9 +36,6 @@ import (
 	"google.golang.org/grpc/credentials/internal"
 )
 
-// alpnProtoStr are the specified application level protocols for gRPC.
-var alpnProtoStr = []string{"h2"}
-
 // PerRPCCredentials defines the common interface for the credentials which need to
 // attach security information to every RPC (e.g., oauth2).
 type PerRPCCredentials interface {
@@ -208,10 +205,23 @@ func (c *tlsCreds) OverrideServerName(serverNameOverride string) error {
 	return nil
 }
 
+const alpnProtoStrH2 = "h2"
+
+func appendH2ToNextProtos(ps []string) []string {
+	for _, p := range ps {
+		if p == alpnProtoStrH2 {
+			return ps
+		}
+	}
+	ret := make([]string, 0, len(ps)+1)
+	ret = append(ret, ps...)
+	return append(ret, alpnProtoStrH2)
+}
+
 // NewTLS uses c to construct a TransportCredentials based on TLS.
 func NewTLS(c *tls.Config) TransportCredentials {
 	tc := &tlsCreds{cloneTLSConfig(c)}
-	tc.config.NextProtos = alpnProtoStr
+	tc.config.NextProtos = appendH2ToNextProtos(tc.config.NextProtos)
 	return tc
 }
 
diff --git a/vendor/google.golang.org/grpc/dialoptions.go b/vendor/google.golang.org/grpc/dialoptions.go
index 537b2586054..e114fecbb7b 100644
--- a/vendor/google.golang.org/grpc/dialoptions.go
+++ b/vendor/google.golang.org/grpc/dialoptions.go
@@ -55,13 +55,16 @@ type dialOptions struct {
 	// balancer, and also by WithBalancerName dial option.
 	balancerBuilder balancer.Builder
 	// This is to support grpclb.
-	resolverBuilder      resolver.Builder
-	reqHandshake         envconfig.RequireHandshakeSetting
-	channelzParentID     int64
-	disableServiceConfig bool
-	disableRetry         bool
-	disableHealthCheck   bool
-	healthCheckFunc      internal.HealthChecker
+	resolverBuilder             resolver.Builder
+	reqHandshake                envconfig.RequireHandshakeSetting
+	channelzParentID            int64
+	disableServiceConfig        bool
+	disableRetry                bool
+	disableHealthCheck          bool
+	healthCheckFunc             internal.HealthChecker
+	minConnectTimeout           func() time.Duration
+	defaultServiceConfig        *ServiceConfig // defaultServiceConfig is parsed from defaultServiceConfigRawJSON.
+	defaultServiceConfigRawJSON *string
 }
 
 // DialOption configures how we set up the connection.
@@ -440,12 +443,27 @@ func WithChannelzParentID(id int64) DialOption {
 // WithDisableServiceConfig returns a DialOption that causes grpc to ignore any
 // service config provided by the resolver and provides a hint to the resolver
 // to not fetch service configs.
+//
+// Note that, this dial option only disables service config from resolver. If
+// default service config is provided, grpc will use the default service config.
 func WithDisableServiceConfig() DialOption {
 	return newFuncDialOption(func(o *dialOptions) {
 		o.disableServiceConfig = true
 	})
 }
 
+// WithDefaultServiceConfig returns a DialOption that configures the default
+// service config, which will be used in cases where:
+// 1. WithDisableServiceConfig is called.
+// 2. Resolver does not return service config or if the resolver gets and invalid config.
+//
+// This API is EXPERIMENTAL.
+func WithDefaultServiceConfig(s string) DialOption {
+	return newFuncDialOption(func(o *dialOptions) {
+		o.defaultServiceConfigRawJSON = &s
+	})
+}
+
 // WithDisableRetry returns a DialOption that disables retries, even if the
 // service config enables them.  This does not impact transparent retries, which
 // will happen automatically if no data is written to the wire or if the RPC is
@@ -470,7 +488,8 @@ func WithMaxHeaderListSize(s uint32) DialOption {
 	})
 }
 
-// WithDisableHealthCheck disables the LB channel health checking for all SubConns of this ClientConn.
+// WithDisableHealthCheck disables the LB channel health checking for all
+// SubConns of this ClientConn.
 //
 // This API is EXPERIMENTAL.
 func WithDisableHealthCheck() DialOption {
@@ -479,8 +498,8 @@ func WithDisableHealthCheck() DialOption {
 	})
 }
 
-// withHealthCheckFunc replaces the default health check function with the provided one. It makes
-// tests easier to change the health check function.
+// withHealthCheckFunc replaces the default health check function with the
+// provided one. It makes tests easier to change the health check function.
 //
 // For testing purpose only.
 func withHealthCheckFunc(f internal.HealthChecker) DialOption {
@@ -500,3 +519,14 @@ func defaultDialOptions() dialOptions {
 		},
 	}
 }
+
+// withGetMinConnectDeadline specifies the function that clientconn uses to
+// get minConnectDeadline. This can be used to make connection attempts happen
+// faster/slower.
+//
+// For testing purpose only.
+func withMinConnectDeadline(f func() time.Duration) DialOption {
+	return newFuncDialOption(func(o *dialOptions) {
+		o.minConnectTimeout = f
+	})
+}
diff --git a/vendor/google.golang.org/grpc/encoding/encoding.go b/vendor/google.golang.org/grpc/encoding/encoding.go
index ade8b7cec73..30a75da99d5 100644
--- a/vendor/google.golang.org/grpc/encoding/encoding.go
+++ b/vendor/google.golang.org/grpc/encoding/encoding.go
@@ -102,10 +102,10 @@ func RegisterCodec(codec Codec) {
 	if codec == nil {
 		panic("cannot register a nil Codec")
 	}
-	contentSubtype := strings.ToLower(codec.Name())
-	if contentSubtype == "" {
-		panic("cannot register Codec with empty string result for String()")
+	if codec.Name() == "" {
+		panic("cannot register Codec with empty string result for Name()")
 	}
+	contentSubtype := strings.ToLower(codec.Name())
 	registeredCodecs[contentSubtype] = codec
 }
 
diff --git a/vendor/google.golang.org/grpc/grpclog/grpclog.go b/vendor/google.golang.org/grpc/grpclog/grpclog.go
index 1fabb11e1ba..51bb9457cda 100644
--- a/vendor/google.golang.org/grpc/grpclog/grpclog.go
+++ b/vendor/google.golang.org/grpc/grpclog/grpclog.go
@@ -18,7 +18,7 @@
 
 // Package grpclog defines logging for grpc.
 //
-// All logs in transport package only go to verbose level 2.
+// All logs in transport and grpclb packages only go to verbose level 2.
 // All logs in other packages in grpc are logged in spite of the verbosity level.
 //
 // In the default logger,
diff --git a/vendor/google.golang.org/grpc/internal/balancerload/load.go b/vendor/google.golang.org/grpc/internal/balancerload/load.go
new file mode 100644
index 00000000000..3a905d96657
--- /dev/null
+++ b/vendor/google.golang.org/grpc/internal/balancerload/load.go
@@ -0,0 +1,46 @@
+/*
+ * Copyright 2019 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// Package balancerload defines APIs to parse server loads in trailers. The
+// parsed loads are sent to balancers in DoneInfo.
+package balancerload
+
+import (
+	"google.golang.org/grpc/metadata"
+)
+
+// Parser converts loads from metadata into a concrete type.
+type Parser interface {
+	// Parse parses loads from metadata.
+	Parse(md metadata.MD) interface{}
+}
+
+var parser Parser
+
+// SetParser sets the load parser.
+//
+// Not mutex-protected, should be called before any gRPC functions.
+func SetParser(lr Parser) {
+	parser = lr
+}
+
+// Parse calls parser.Read().
+func Parse(md metadata.MD) interface{} {
+	if parser == nil {
+		return nil
+	}
+	return parser.Parse(md)
+}
diff --git a/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go b/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go
index 62ed0f2f120..11be7cd08c5 100644
--- a/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go
+++ b/vendor/google.golang.org/grpc/internal/envconfig/envconfig.go
@@ -34,13 +34,9 @@ const (
 type RequireHandshakeSetting int
 
 const (
-	// RequireHandshakeHybrid (default, deprecated) indicates to not wait for
-	// handshake before considering a connection ready, but wait before
-	// considering successful.
-	RequireHandshakeHybrid RequireHandshakeSetting = iota
-	// RequireHandshakeOn (default after the 1.17 release) indicates to wait
-	// for handshake before considering a connection ready/successful.
-	RequireHandshakeOn
+	// RequireHandshakeOn indicates to wait for handshake before considering a
+	// connection ready/successful.
+	RequireHandshakeOn RequireHandshakeSetting = iota
 	// RequireHandshakeOff indicates to not wait for handshake before
 	// considering a connection ready/successful.
 	RequireHandshakeOff
@@ -53,7 +49,7 @@ var (
 	// environment variable.
 	//
 	// Will be removed after the 1.18 release.
-	RequireHandshake RequireHandshakeSetting
+	RequireHandshake = RequireHandshakeOn
 )
 
 func init() {
@@ -64,8 +60,5 @@ func init() {
 		RequireHandshake = RequireHandshakeOn
 	case "off":
 		RequireHandshake = RequireHandshakeOff
-	case "hybrid":
-		// Will be removed after the 1.17 release.
-		RequireHandshake = RequireHandshakeHybrid
 	}
 }
diff --git a/vendor/google.golang.org/grpc/internal/syscall/syscall_nonlinux.go b/vendor/google.golang.org/grpc/internal/syscall/syscall_nonlinux.go
index 61678feb004..d3fd9dab333 100644
--- a/vendor/google.golang.org/grpc/internal/syscall/syscall_nonlinux.go
+++ b/vendor/google.golang.org/grpc/internal/syscall/syscall_nonlinux.go
@@ -22,18 +22,24 @@ package syscall
 
 import (
 	"net"
+	"sync"
 	"time"
 
 	"google.golang.org/grpc/grpclog"
 )
 
-func init() {
-	grpclog.Info("CPU time info is unavailable on non-linux or appengine environment.")
+var once sync.Once
+
+func log() {
+	once.Do(func() {
+		grpclog.Info("CPU time info is unavailable on non-linux or appengine environment.")
+	})
 }
 
 // GetCPUTime returns the how much CPU time has passed since the start of this process.
 // It always returns 0 under non-linux or appengine environment.
 func GetCPUTime() int64 {
+	log()
 	return 0
 }
 
@@ -42,22 +48,26 @@ type Rusage struct{}
 
 // GetRusage is a no-op function under non-linux or appengine environment.
 func GetRusage() (rusage *Rusage) {
+	log()
 	return nil
 }
 
 // CPUTimeDiff returns the differences of user CPU time and system CPU time used
 // between two Rusage structs. It a no-op function for non-linux or appengine environment.
 func CPUTimeDiff(first *Rusage, latest *Rusage) (float64, float64) {
+	log()
 	return 0, 0
 }
 
 // SetTCPUserTimeout is a no-op function under non-linux or appengine environments
 func SetTCPUserTimeout(conn net.Conn, timeout time.Duration) error {
+	log()
 	return nil
 }
 
 // GetTCPUserTimeout is a no-op function under non-linux or appengine environments
 // a negative return value indicates the operation is not supported
 func GetTCPUserTimeout(conn net.Conn) (int, error) {
+	log()
 	return -1, nil
 }
diff --git a/vendor/google.golang.org/grpc/internal/transport/handler_server.go b/vendor/google.golang.org/grpc/internal/transport/handler_server.go
index 73b41ea7e0b..f2de84d43a8 100644
--- a/vendor/google.golang.org/grpc/internal/transport/handler_server.go
+++ b/vendor/google.golang.org/grpc/internal/transport/handler_server.go
@@ -63,9 +63,6 @@ func NewServerHandlerTransport(w http.ResponseWriter, r *http.Request, stats sta
 	if _, ok := w.(http.Flusher); !ok {
 		return nil, errors.New("gRPC requires a ResponseWriter supporting http.Flusher")
 	}
-	if _, ok := w.(http.CloseNotifier); !ok {
-		return nil, errors.New("gRPC requires a ResponseWriter supporting http.CloseNotifier")
-	}
 
 	st := &serverHandlerTransport{
 		rw:             w,
@@ -176,17 +173,11 @@ func (a strAddr) String() string { return string(a) }
 
 // do runs fn in the ServeHTTP goroutine.
 func (ht *serverHandlerTransport) do(fn func()) error {
-	// Avoid a panic writing to closed channel. Imperfect but maybe good enough.
 	select {
 	case <-ht.closedCh:
 		return ErrConnClosing
-	default:
-		select {
-		case ht.writes <- fn:
-			return nil
-		case <-ht.closedCh:
-			return ErrConnClosing
-		}
+	case ht.writes <- fn:
+		return nil
 	}
 }
 
@@ -237,7 +228,6 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, st *status.Status) erro
 		if ht.stats != nil {
 			ht.stats.HandleRPC(s.Context(), &stats.OutTrailer{})
 		}
-		close(ht.writes)
 	}
 	ht.Close()
 	return err
@@ -315,19 +305,13 @@ func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), trace
 		ctx, cancel = context.WithCancel(ctx)
 	}
 
-	// requestOver is closed when either the request's context is done
-	// or the status has been written via WriteStatus.
+	// requestOver is closed when the status has been written via WriteStatus.
 	requestOver := make(chan struct{})
-
-	// clientGone receives a single value if peer is gone, either
-	// because the underlying connection is dead or because the
-	// peer sends an http2 RST_STREAM.
-	clientGone := ht.rw.(http.CloseNotifier).CloseNotify()
 	go func() {
 		select {
 		case <-requestOver:
 		case <-ht.closedCh:
-		case <-clientGone:
+		case <-ht.req.Context().Done():
 		}
 		cancel()
 		ht.Close()
@@ -407,10 +391,7 @@ func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), trace
 func (ht *serverHandlerTransport) runStream() {
 	for {
 		select {
-		case fn, ok := <-ht.writes:
-			if !ok {
-				return
-			}
+		case fn := <-ht.writes:
 			fn()
 		case <-ht.closedCh:
 			return
diff --git a/vendor/google.golang.org/grpc/internal/transport/http2_client.go b/vendor/google.golang.org/grpc/internal/transport/http2_client.go
index ff8f4db08ba..9dee6db61d9 100644
--- a/vendor/google.golang.org/grpc/internal/transport/http2_client.go
+++ b/vendor/google.golang.org/grpc/internal/transport/http2_client.go
@@ -1140,15 +1140,27 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 	if !ok {
 		return
 	}
+	endStream := frame.StreamEnded()
 	atomic.StoreUint32(&s.bytesReceived, 1)
-	var state decodeState
+	initialHeader := atomic.SwapUint32(&s.headerDone, 1) == 0
+
+	if !initialHeader && !endStream {
+		// As specified by RFC 7540, a HEADERS frame (and associated CONTINUATION frames) can only appear
+		// at the start or end of a stream. Therefore, second HEADERS frame must have EOS bit set.
+		st := status.New(codes.Internal, "a HEADERS frame cannot appear in the middle of a stream")
+		t.closeStream(s, st.Err(), true, http2.ErrCodeProtocol, st, nil, false)
+		return
+	}
+
+	state := &decodeState{}
+	// Initialize isGRPC value to be !initialHeader, since if a gRPC ResponseHeader has been received
+	// which indicates peer speaking gRPC, we are in gRPC mode.
+	state.data.isGRPC = !initialHeader
 	if err := state.decodeHeader(frame); err != nil {
-		t.closeStream(s, err, true, http2.ErrCodeProtocol, status.New(codes.Internal, err.Error()), nil, false)
-		// Something wrong. Stops reading even when there is remaining.
+		t.closeStream(s, err, true, http2.ErrCodeProtocol, status.Convert(err), nil, endStream)
 		return
 	}
 
-	endStream := frame.StreamEnded()
 	var isHeader bool
 	defer func() {
 		if t.statsHandler != nil {
@@ -1167,29 +1179,30 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 			}
 		}
 	}()
+
 	// If headers haven't been received yet.
-	if atomic.SwapUint32(&s.headerDone, 1) == 0 {
+	if initialHeader {
 		if !endStream {
-			// Headers frame is not actually a trailers-only frame.
+			// Headers frame is ResponseHeader.
 			isHeader = true
 			// These values can be set without any synchronization because
 			// stream goroutine will read it only after seeing a closed
 			// headerChan which we'll close after setting this.
-			s.recvCompress = state.encoding
-			if len(state.mdata) > 0 {
-				s.header = state.mdata
+			s.recvCompress = state.data.encoding
+			if len(state.data.mdata) > 0 {
+				s.header = state.data.mdata
 			}
-		} else {
-			s.noHeaders = true
+			close(s.headerChan)
+			return
 		}
+		// Headers frame is Trailers-only.
+		s.noHeaders = true
 		close(s.headerChan)
 	}
-	if !endStream {
-		return
-	}
+
 	// if client received END_STREAM from server while stream was still active, send RST_STREAM
 	rst := s.getState() == streamActive
-	t.closeStream(s, io.EOF, rst, http2.ErrCodeNo, state.status(), state.mdata, true)
+	t.closeStream(s, io.EOF, rst, http2.ErrCodeNo, state.status(), state.data.mdata, true)
 }
 
 // reader runs as a separate goroutine in charge of reading data from network
@@ -1356,6 +1369,8 @@ func (t *http2Client) ChannelzMetric() *channelz.SocketInternalMetric {
 	return &s
 }
 
+func (t *http2Client) RemoteAddr() net.Addr { return t.remoteAddr }
+
 func (t *http2Client) IncrMsgSent() {
 	atomic.AddInt64(&t.czData.msgSent, 1)
 	atomic.StoreInt64(&t.czData.lastMsgSentTime, time.Now().UnixNano())
diff --git a/vendor/google.golang.org/grpc/internal/transport/http2_server.go b/vendor/google.golang.org/grpc/internal/transport/http2_server.go
index d038b2dfef5..435092e5c85 100644
--- a/vendor/google.golang.org/grpc/internal/transport/http2_server.go
+++ b/vendor/google.golang.org/grpc/internal/transport/http2_server.go
@@ -286,7 +286,9 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 // operateHeader takes action on the decoded headers.
 func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(*Stream), traceCtx func(context.Context, string) context.Context) (fatal bool) {
 	streamID := frame.Header().StreamID
-	state := decodeState{serverSide: true}
+	state := &decodeState{
+		serverSide: true,
+	}
 	if err := state.decodeHeader(frame); err != nil {
 		if se, ok := status.FromError(err); ok {
 			t.controlBuf.put(&cleanupStream{
@@ -305,16 +307,16 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 		st:             t,
 		buf:            buf,
 		fc:             &inFlow{limit: uint32(t.initialWindowSize)},
-		recvCompress:   state.encoding,
-		method:         state.method,
-		contentSubtype: state.contentSubtype,
+		recvCompress:   state.data.encoding,
+		method:         state.data.method,
+		contentSubtype: state.data.contentSubtype,
 	}
 	if frame.StreamEnded() {
 		// s is just created by the caller. No lock needed.
 		s.state = streamReadDone
 	}
-	if state.timeoutSet {
-		s.ctx, s.cancel = context.WithTimeout(t.ctx, state.timeout)
+	if state.data.timeoutSet {
+		s.ctx, s.cancel = context.WithTimeout(t.ctx, state.data.timeout)
 	} else {
 		s.ctx, s.cancel = context.WithCancel(t.ctx)
 	}
@@ -327,19 +329,19 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	}
 	s.ctx = peer.NewContext(s.ctx, pr)
 	// Attach the received metadata to the context.
-	if len(state.mdata) > 0 {
-		s.ctx = metadata.NewIncomingContext(s.ctx, state.mdata)
+	if len(state.data.mdata) > 0 {
+		s.ctx = metadata.NewIncomingContext(s.ctx, state.data.mdata)
 	}
-	if state.statsTags != nil {
-		s.ctx = stats.SetIncomingTags(s.ctx, state.statsTags)
+	if state.data.statsTags != nil {
+		s.ctx = stats.SetIncomingTags(s.ctx, state.data.statsTags)
 	}
-	if state.statsTrace != nil {
-		s.ctx = stats.SetIncomingTrace(s.ctx, state.statsTrace)
+	if state.data.statsTrace != nil {
+		s.ctx = stats.SetIncomingTrace(s.ctx, state.data.statsTrace)
 	}
 	if t.inTapHandle != nil {
 		var err error
 		info := &tap.Info{
-			FullMethodName: state.method,
+			FullMethodName: state.data.method,
 		}
 		s.ctx, err = t.inTapHandle(s.ctx, info)
 		if err != nil {
@@ -435,7 +437,7 @@ func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.
 				s := t.activeStreams[se.StreamID]
 				t.mu.Unlock()
 				if s != nil {
-					t.closeStream(s, true, se.Code, nil, false)
+					t.closeStream(s, true, se.Code, false)
 				} else {
 					t.controlBuf.put(&cleanupStream{
 						streamID: se.StreamID,
@@ -577,7 +579,7 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 	}
 	if size > 0 {
 		if err := s.fc.onData(size); err != nil {
-			t.closeStream(s, true, http2.ErrCodeFlowControl, nil, false)
+			t.closeStream(s, true, http2.ErrCodeFlowControl, false)
 			return
 		}
 		if f.Header().Flags.Has(http2.FlagDataPadded) {
@@ -602,11 +604,18 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 }
 
 func (t *http2Server) handleRSTStream(f *http2.RSTStreamFrame) {
-	s, ok := t.getStream(f)
-	if !ok {
+	// If the stream is not deleted from the transport's active streams map, then do a regular close stream.
+	if s, ok := t.getStream(f); ok {
+		t.closeStream(s, false, 0, false)
 		return
 	}
-	t.closeStream(s, false, 0, nil, false)
+	// If the stream is already deleted from the active streams map, then put a cleanupStream item into controlbuf to delete the stream from loopy writer's established streams map.
+	t.controlBuf.put(&cleanupStream{
+		streamID: f.Header().StreamID,
+		rst:      false,
+		rstCode:  0,
+		onWrite:  func() {},
+	})
 }
 
 func (t *http2Server) handleSettings(f *http2.SettingsFrame) {
@@ -770,7 +779,7 @@ func (t *http2Server) writeHeaderLocked(s *Stream) error {
 		if err != nil {
 			return err
 		}
-		t.closeStream(s, true, http2.ErrCodeInternal, nil, false)
+		t.closeStream(s, true, http2.ErrCodeInternal, false)
 		return ErrHeaderListSizeLimitViolation
 	}
 	if t.stats != nil {
@@ -834,10 +843,12 @@ func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 		if err != nil {
 			return err
 		}
-		t.closeStream(s, true, http2.ErrCodeInternal, nil, false)
+		t.closeStream(s, true, http2.ErrCodeInternal, false)
 		return ErrHeaderListSizeLimitViolation
 	}
-	t.closeStream(s, false, 0, trailingHeader, true)
+	// Send a RST_STREAM after the trailers if the client has not already half-closed.
+	rst := s.getState() == streamActive
+	t.finishStream(s, rst, http2.ErrCodeNo, trailingHeader, true)
 	if t.stats != nil {
 		t.stats.HandleRPC(s.Context(), &stats.OutTrailer{})
 	}
@@ -849,6 +860,9 @@ func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 func (t *http2Server) Write(s *Stream, hdr []byte, data []byte, opts *Options) error {
 	if !s.isHeaderSent() { // Headers haven't been written yet.
 		if err := t.WriteHeader(s, nil); err != nil {
+			if _, ok := err.(ConnectionError); ok {
+				return err
+			}
 			// TODO(mmukhi, dfawley): Make sure this is the right code to return.
 			return status.Errorf(codes.Internal, "transport: %v", err)
 		}
@@ -1005,16 +1019,24 @@ func (t *http2Server) Close() error {
 }
 
 // deleteStream deletes the stream s from transport's active streams.
-func (t *http2Server) deleteStream(s *Stream, eosReceived bool) {
-	t.mu.Lock()
-	if _, ok := t.activeStreams[s.id]; !ok {
-		t.mu.Unlock()
-		return
+func (t *http2Server) deleteStream(s *Stream, eosReceived bool) (oldState streamState) {
+	oldState = s.swapState(streamDone)
+	if oldState == streamDone {
+		// If the stream was already done, return.
+		return oldState
 	}
 
-	delete(t.activeStreams, s.id)
-	if len(t.activeStreams) == 0 {
-		t.idle = time.Now()
+	// In case stream sending and receiving are invoked in separate
+	// goroutines (e.g., bi-directional streaming), cancel needs to be
+	// called to interrupt the potential blocking on other goroutines.
+	s.cancel()
+
+	t.mu.Lock()
+	if _, ok := t.activeStreams[s.id]; ok {
+		delete(t.activeStreams, s.id)
+		if len(t.activeStreams) == 0 {
+			t.idle = time.Now()
+		}
 	}
 	t.mu.Unlock()
 
@@ -1025,55 +1047,38 @@ func (t *http2Server) deleteStream(s *Stream, eosReceived bool) {
 			atomic.AddInt64(&t.czData.streamsFailed, 1)
 		}
 	}
-}
-
-// closeStream clears the footprint of a stream when the stream is not needed
-// any more.
-func (t *http2Server) closeStream(s *Stream, rst bool, rstCode http2.ErrCode, hdr *headerFrame, eosReceived bool) {
-	// Mark the stream as done
-	oldState := s.swapState(streamDone)
 
-	// In case stream sending and receiving are invoked in separate
-	// goroutines (e.g., bi-directional streaming), cancel needs to be
-	// called to interrupt the potential blocking on other goroutines.
-	s.cancel()
+	return oldState
+}
 
-	// Deletes the stream from active streams
-	t.deleteStream(s, eosReceived)
+// finishStream closes the stream and puts the trailing headerFrame into controlbuf.
+func (t *http2Server) finishStream(s *Stream, rst bool, rstCode http2.ErrCode, hdr *headerFrame, eosReceived bool) {
+	oldState := t.deleteStream(s, eosReceived)
+	// If the stream is already closed, then don't put trailing header to controlbuf.
+	if oldState == streamDone {
+		return
+	}
 
-	cleanup := &cleanupStream{
+	hdr.cleanup = &cleanupStream{
 		streamID: s.id,
 		rst:      rst,
 		rstCode:  rstCode,
 		onWrite:  func() {},
 	}
-
-	// No trailer. Puts cleanupFrame into transport's control buffer.
-	if hdr == nil {
-		t.controlBuf.put(cleanup)
-		return
-	}
-
-	// We do the check here, because of the following scenario:
-	// 1. closeStream is called first with a trailer. A trailer item with a piggybacked cleanup item
-	// is put to control buffer.
-	// 2. Loopy writer is waiting on a stream quota. It will never get it because client errored at
-	// some point. So loopy can't act on trailer
-	// 3. Client sends a RST_STREAM due to the error. Then closeStream is called without a trailer as
-	// the result of the received RST_STREAM.
-	// If we do this check at the beginning of the closeStream, then we won't put a cleanup item in
-	// response to received RST_STREAM into the control buffer and outStream in loopy writer will
-	// never get cleaned up.
-
-	// If the stream is already done, don't send the trailer.
-	if oldState == streamDone {
-		return
-	}
-
-	hdr.cleanup = cleanup
 	t.controlBuf.put(hdr)
 }
 
+// closeStream clears the footprint of a stream when the stream is not needed any more.
+func (t *http2Server) closeStream(s *Stream, rst bool, rstCode http2.ErrCode, eosReceived bool) {
+	t.deleteStream(s, eosReceived)
+	t.controlBuf.put(&cleanupStream{
+		streamID: s.id,
+		rst:      rst,
+		rstCode:  rstCode,
+		onWrite:  func() {},
+	})
+}
+
 func (t *http2Server) RemoteAddr() net.Addr {
 	return t.remoteAddr
 }
diff --git a/vendor/google.golang.org/grpc/internal/transport/http_util.go b/vendor/google.golang.org/grpc/internal/transport/http_util.go
index 77a2cfaaef3..9d212867ce2 100644
--- a/vendor/google.golang.org/grpc/internal/transport/http_util.go
+++ b/vendor/google.golang.org/grpc/internal/transport/http_util.go
@@ -78,7 +78,8 @@ var (
 		codes.ResourceExhausted: http2.ErrCodeEnhanceYourCalm,
 		codes.PermissionDenied:  http2.ErrCodeInadequateSecurity,
 	}
-	httpStatusConvTab = map[int]codes.Code{
+	// HTTPStatusConvTab is the HTTP status code to gRPC error code conversion table.
+	HTTPStatusConvTab = map[int]codes.Code{
 		// 400 Bad Request - INTERNAL.
 		http.StatusBadRequest: codes.Internal,
 		// 401 Unauthorized  - UNAUTHENTICATED.
@@ -98,9 +99,7 @@ var (
 	}
 )
 
-// Records the states during HPACK decoding. Must be reset once the
-// decoding of the entire headers are finished.
-type decodeState struct {
+type parsedHeaderData struct {
 	encoding string
 	// statusGen caches the stream status received from the trailer the server
 	// sent.  Client side only.  Do not access directly.  After all trailers are
@@ -120,8 +119,30 @@ type decodeState struct {
 	statsTags      []byte
 	statsTrace     []byte
 	contentSubtype string
+
+	// isGRPC field indicates whether the peer is speaking gRPC (otherwise HTTP).
+	//
+	// We are in gRPC mode (peer speaking gRPC) if:
+	// 	* We are client side and have already received a HEADER frame that indicates gRPC peer.
+	//  * The header contains valid  a content-type, i.e. a string starts with "application/grpc"
+	// And we should handle error specific to gRPC.
+	//
+	// Otherwise (i.e. a content-type string starts without "application/grpc", or does not exist), we
+	// are in HTTP fallback mode, and should handle error specific to HTTP.
+	isGRPC         bool
+	grpcErr        error
+	httpErr        error
+	contentTypeErr string
+}
+
+// decodeState configures decoding criteria and records the decoded data.
+type decodeState struct {
 	// whether decoding on server side or not
 	serverSide bool
+
+	// Records the states during HPACK decoding. It will be filled with info parsed from HTTP HEADERS
+	// frame once decodeHeader function has been invoked and returned.
+	data parsedHeaderData
 }
 
 // isReservedHeader checks whether hdr belongs to HTTP2 headers
@@ -202,11 +223,11 @@ func contentType(contentSubtype string) string {
 }
 
 func (d *decodeState) status() *status.Status {
-	if d.statusGen == nil {
+	if d.data.statusGen == nil {
 		// No status-details were provided; generate status using code/msg.
-		d.statusGen = status.New(codes.Code(int32(*(d.rawStatusCode))), d.rawStatusMsg)
+		d.data.statusGen = status.New(codes.Code(int32(*(d.data.rawStatusCode))), d.data.rawStatusMsg)
 	}
-	return d.statusGen
+	return d.data.statusGen
 }
 
 const binHdrSuffix = "-bin"
@@ -244,113 +265,146 @@ func (d *decodeState) decodeHeader(frame *http2.MetaHeadersFrame) error {
 	if frame.Truncated {
 		return status.Error(codes.Internal, "peer header list size exceeded limit")
 	}
+
 	for _, hf := range frame.Fields {
-		if err := d.processHeaderField(hf); err != nil {
-			return err
-		}
+		d.processHeaderField(hf)
 	}
 
-	if d.serverSide {
+	if d.data.isGRPC {
+		if d.data.grpcErr != nil {
+			return d.data.grpcErr
+		}
+		if d.serverSide {
+			return nil
+		}
+		if d.data.rawStatusCode == nil && d.data.statusGen == nil {
+			// gRPC status doesn't exist.
+			// Set rawStatusCode to be unknown and return nil error.
+			// So that, if the stream has ended this Unknown status
+			// will be propagated to the user.
+			// Otherwise, it will be ignored. In which case, status from
+			// a later trailer, that has StreamEnded flag set, is propagated.
+			code := int(codes.Unknown)
+			d.data.rawStatusCode = &code
+		}
 		return nil
 	}
 
-	// If grpc status exists, no need to check further.
-	if d.rawStatusCode != nil || d.statusGen != nil {
-		return nil
+	// HTTP fallback mode
+	if d.data.httpErr != nil {
+		return d.data.httpErr
 	}
 
-	// If grpc status doesn't exist and http status doesn't exist,
-	// then it's a malformed header.
-	if d.httpStatus == nil {
-		return status.Error(codes.Internal, "malformed header: doesn't contain status(gRPC or HTTP)")
-	}
+	var (
+		code = codes.Internal // when header does not include HTTP status, return INTERNAL
+		ok   bool
+	)
 
-	if *(d.httpStatus) != http.StatusOK {
-		code, ok := httpStatusConvTab[*(d.httpStatus)]
+	if d.data.httpStatus != nil {
+		code, ok = HTTPStatusConvTab[*(d.data.httpStatus)]
 		if !ok {
 			code = codes.Unknown
 		}
-		return status.Error(code, http.StatusText(*(d.httpStatus)))
-	}
-
-	// gRPC status doesn't exist and http status is OK.
-	// Set rawStatusCode to be unknown and return nil error.
-	// So that, if the stream has ended this Unknown status
-	// will be propagated to the user.
-	// Otherwise, it will be ignored. In which case, status from
-	// a later trailer, that has StreamEnded flag set, is propagated.
-	code := int(codes.Unknown)
-	d.rawStatusCode = &code
-	return nil
+	}
+
+	return status.Error(code, d.constructHTTPErrMsg())
+}
+
+// constructErrMsg constructs error message to be returned in HTTP fallback mode.
+// Format: HTTP status code and its corresponding message + content-type error message.
+func (d *decodeState) constructHTTPErrMsg() string {
+	var errMsgs []string
+
+	if d.data.httpStatus == nil {
+		errMsgs = append(errMsgs, "malformed header: missing HTTP status")
+	} else {
+		errMsgs = append(errMsgs, fmt.Sprintf("%s: HTTP status code %d", http.StatusText(*(d.data.httpStatus)), *d.data.httpStatus))
+	}
+
+	if d.data.contentTypeErr == "" {
+		errMsgs = append(errMsgs, "transport: missing content-type field")
+	} else {
+		errMsgs = append(errMsgs, d.data.contentTypeErr)
+	}
+
+	return strings.Join(errMsgs, "; ")
 }
 
 func (d *decodeState) addMetadata(k, v string) {
-	if d.mdata == nil {
-		d.mdata = make(map[string][]string)
+	if d.data.mdata == nil {
+		d.data.mdata = make(map[string][]string)
 	}
-	d.mdata[k] = append(d.mdata[k], v)
+	d.data.mdata[k] = append(d.data.mdata[k], v)
 }
 
-func (d *decodeState) processHeaderField(f hpack.HeaderField) error {
+func (d *decodeState) processHeaderField(f hpack.HeaderField) {
 	switch f.Name {
 	case "content-type":
 		contentSubtype, validContentType := contentSubtype(f.Value)
 		if !validContentType {
-			return status.Errorf(codes.Internal, "transport: received the unexpected content-type %q", f.Value)
+			d.data.contentTypeErr = fmt.Sprintf("transport: received the unexpected content-type %q", f.Value)
+			return
 		}
-		d.contentSubtype = contentSubtype
+		d.data.contentSubtype = contentSubtype
 		// TODO: do we want to propagate the whole content-type in the metadata,
 		// or come up with a way to just propagate the content-subtype if it was set?
 		// ie {"content-type": "application/grpc+proto"} or {"content-subtype": "proto"}
 		// in the metadata?
 		d.addMetadata(f.Name, f.Value)
+		d.data.isGRPC = true
 	case "grpc-encoding":
-		d.encoding = f.Value
+		d.data.encoding = f.Value
 	case "grpc-status":
 		code, err := strconv.Atoi(f.Value)
 		if err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed grpc-status: %v", err)
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-status: %v", err)
+			return
 		}
-		d.rawStatusCode = &code
+		d.data.rawStatusCode = &code
 	case "grpc-message":
-		d.rawStatusMsg = decodeGrpcMessage(f.Value)
+		d.data.rawStatusMsg = decodeGrpcMessage(f.Value)
 	case "grpc-status-details-bin":
 		v, err := decodeBinHeader(f.Value)
 		if err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+			return
 		}
 		s := &spb.Status{}
 		if err := proto.Unmarshal(v, s); err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+			return
 		}
-		d.statusGen = status.FromProto(s)
+		d.data.statusGen = status.FromProto(s)
 	case "grpc-timeout":
-		d.timeoutSet = true
+		d.data.timeoutSet = true
 		var err error
-		if d.timeout, err = decodeTimeout(f.Value); err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed time-out: %v", err)
+		if d.data.timeout, err = decodeTimeout(f.Value); err != nil {
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed time-out: %v", err)
 		}
 	case ":path":
-		d.method = f.Value
+		d.data.method = f.Value
 	case ":status":
 		code, err := strconv.Atoi(f.Value)
 		if err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed http-status: %v", err)
+			d.data.httpErr = status.Errorf(codes.Internal, "transport: malformed http-status: %v", err)
+			return
 		}
-		d.httpStatus = &code
+		d.data.httpStatus = &code
 	case "grpc-tags-bin":
 		v, err := decodeBinHeader(f.Value)
 		if err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed grpc-tags-bin: %v", err)
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-tags-bin: %v", err)
+			return
 		}
-		d.statsTags = v
+		d.data.statsTags = v
 		d.addMetadata(f.Name, string(v))
 	case "grpc-trace-bin":
 		v, err := decodeBinHeader(f.Value)
 		if err != nil {
-			return status.Errorf(codes.Internal, "transport: malformed grpc-trace-bin: %v", err)
+			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-trace-bin: %v", err)
+			return
 		}
-		d.statsTrace = v
+		d.data.statsTrace = v
 		d.addMetadata(f.Name, string(v))
 	default:
 		if isReservedHeader(f.Name) && !isWhitelistedHeader(f.Name) {
@@ -359,11 +413,10 @@ func (d *decodeState) processHeaderField(f hpack.HeaderField) error {
 		v, err := decodeMetadataHeader(f.Name, f.Value)
 		if err != nil {
 			errorf("Failed to decode metadata header (%q, %q): %v", f.Name, f.Value, err)
-			return nil
+			return
 		}
 		d.addMetadata(f.Name, v)
 	}
-	return nil
 }
 
 type timeoutUnit uint8
diff --git a/vendor/google.golang.org/grpc/internal/transport/transport.go b/vendor/google.golang.org/grpc/internal/transport/transport.go
index 2580aa7d3ba..7f82cbb080d 100644
--- a/vendor/google.golang.org/grpc/internal/transport/transport.go
+++ b/vendor/google.golang.org/grpc/internal/transport/transport.go
@@ -327,8 +327,7 @@ func (s *Stream) TrailersOnly() (bool, error) {
 	if err != nil {
 		return false, err
 	}
-	// if !headerDone, some other connection error occurred.
-	return s.noHeaders && atomic.LoadUint32(&s.headerDone) == 1, nil
+	return s.noHeaders, nil
 }
 
 // Trailer returns the cached trailer metedata. Note that if it is not called
@@ -611,6 +610,9 @@ type ClientTransport interface {
 	// GetGoAwayReason returns the reason why GoAway frame was received.
 	GetGoAwayReason() GoAwayReason
 
+	// RemoteAddr returns the remote network address.
+	RemoteAddr() net.Addr
+
 	// IncrMsgSent increments the number of message sent through this transport.
 	IncrMsgSent()
 
diff --git a/vendor/google.golang.org/grpc/picker_wrapper.go b/vendor/google.golang.org/grpc/picker_wrapper.go
index a2575c9637b..f9625496c40 100644
--- a/vendor/google.golang.org/grpc/picker_wrapper.go
+++ b/vendor/google.golang.org/grpc/picker_wrapper.go
@@ -165,6 +165,11 @@ func (bp *pickerWrapper) pick(ctx context.Context, failfast bool, opts balancer.
 			}
 			return t, done, nil
 		}
+		if done != nil {
+			// Calling done with nil error, no bytes sent and no bytes received.
+			// DoneInfo with default value works.
+			done(balancer.DoneInfo{})
+		}
 		grpclog.Infof("blockingPicker: the picked transport is not ready, loop back to repick")
 		// If ok == false, ac.state is not READY.
 		// A valid picker always returns READY subConn. This means the state of ac
diff --git a/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go b/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go
index 2d8da331d27..58355990779 100644
--- a/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go
+++ b/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go
@@ -47,6 +47,8 @@ const (
 	defaultFreq       = time.Minute * 30
 	defaultDNSSvrPort = "53"
 	golang            = "GO"
+	// txtPrefix is the prefix string to be prepended to the host name for txt record lookup.
+	txtPrefix = "_grpc_config."
 	// In DNS, service config is encoded in a TXT record via the mechanism
 	// described in RFC-1464 using the attribute name grpc_config.
 	txtAttribute = "grpc_config="
@@ -282,7 +284,7 @@ func (d *dnsResolver) lookupSRV() []resolver.Address {
 }
 
 func (d *dnsResolver) lookupTXT() string {
-	ss, err := d.resolver.LookupTXT(d.ctx, d.host)
+	ss, err := d.resolver.LookupTXT(d.ctx, txtPrefix+d.host)
 	if err != nil {
 		grpclog.Infof("grpc: failed dns TXT record lookup due to %v.\n", err)
 		return ""
diff --git a/vendor/google.golang.org/grpc/resolver/passthrough/passthrough.go b/vendor/google.golang.org/grpc/resolver/passthrough/passthrough.go
index b76010d74d1..893d5d12cb0 100644
--- a/vendor/google.golang.org/grpc/resolver/passthrough/passthrough.go
+++ b/vendor/google.golang.org/grpc/resolver/passthrough/passthrough.go
@@ -45,7 +45,7 @@ type passthroughResolver struct {
 }
 
 func (r *passthroughResolver) start() {
-	r.cc.NewAddress([]resolver.Address{{Addr: r.target.Endpoint}})
+	r.cc.UpdateState(resolver.State{Addresses: []resolver.Address{{Addr: r.target.Endpoint}}})
 }
 
 func (*passthroughResolver) ResolveNow(o resolver.ResolveNowOption) {}
diff --git a/vendor/google.golang.org/grpc/resolver/resolver.go b/vendor/google.golang.org/grpc/resolver/resolver.go
index 145cf477edb..52ec603daa7 100644
--- a/vendor/google.golang.org/grpc/resolver/resolver.go
+++ b/vendor/google.golang.org/grpc/resolver/resolver.go
@@ -98,6 +98,15 @@ type BuildOption struct {
 	DisableServiceConfig bool
 }
 
+// State contains the current Resolver state relevant to the ClientConn.
+type State struct {
+	Addresses     []Address // Resolved addresses for the target
+	ServiceConfig string    // JSON representation of the service config
+
+	// TODO: add Err error
+	// TODO: add ParsedServiceConfig interface{}
+}
+
 // ClientConn contains the callbacks for resolver to notify any updates
 // to the gRPC ClientConn.
 //
@@ -106,12 +115,18 @@ type BuildOption struct {
 // testing, the new implementation should embed this interface. This allows
 // gRPC to add new methods to this interface.
 type ClientConn interface {
+	// UpdateState updates the state of the ClientConn appropriately.
+	UpdateState(State)
 	// NewAddress is called by resolver to notify ClientConn a new list
 	// of resolved addresses.
 	// The address list should be the complete list of resolved addresses.
+	//
+	// Deprecated: Use UpdateState instead.
 	NewAddress(addresses []Address)
 	// NewServiceConfig is called by resolver to notify ClientConn a new
 	// service config. The service config should be provided as a json string.
+	//
+	// Deprecated: Use UpdateState instead.
 	NewServiceConfig(serviceConfig string)
 }
 
diff --git a/vendor/google.golang.org/grpc/resolver_conn_wrapper.go b/vendor/google.golang.org/grpc/resolver_conn_wrapper.go
index 50991eafb91..e9cef3a92b5 100644
--- a/vendor/google.golang.org/grpc/resolver_conn_wrapper.go
+++ b/vendor/google.golang.org/grpc/resolver_conn_wrapper.go
@@ -21,6 +21,7 @@ package grpc
 import (
 	"fmt"
 	"strings"
+	"sync/atomic"
 
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal/channelz"
@@ -30,12 +31,12 @@ import (
 // ccResolverWrapper is a wrapper on top of cc for resolvers.
 // It implements resolver.ClientConnection interface.
 type ccResolverWrapper struct {
-	cc                 *ClientConn
-	resolver           resolver.Resolver
-	addrCh             chan []resolver.Address
-	scCh               chan string
-	done               chan struct{}
-	lastAddressesCount int
+	cc       *ClientConn
+	resolver resolver.Resolver
+	addrCh   chan []resolver.Address
+	scCh     chan string
+	done     uint32 // accessed atomically; set to 1 when closed.
+	curState resolver.State
 }
 
 // split2 returns the values from strings.SplitN(s, sep, 2).
@@ -82,7 +83,6 @@ func newCCResolverWrapper(cc *ClientConn) (*ccResolverWrapper, error) {
 		cc:     cc,
 		addrCh: make(chan []resolver.Address, 1),
 		scCh:   make(chan string, 1),
-		done:   make(chan struct{}),
 	}
 
 	var err error
@@ -99,57 +99,67 @@ func (ccr *ccResolverWrapper) resolveNow(o resolver.ResolveNowOption) {
 
 func (ccr *ccResolverWrapper) close() {
 	ccr.resolver.Close()
-	close(ccr.done)
+	atomic.StoreUint32(&ccr.done, 1)
 }
 
-// NewAddress is called by the resolver implemenetion to send addresses to gRPC.
+func (ccr *ccResolverWrapper) isDone() bool {
+	return atomic.LoadUint32(&ccr.done) == 1
+}
+
+func (ccr *ccResolverWrapper) UpdateState(s resolver.State) {
+	if ccr.isDone() {
+		return
+	}
+	grpclog.Infof("ccResolverWrapper: sending update to cc: %v", s)
+	if channelz.IsOn() {
+		ccr.addChannelzTraceEvent(s)
+	}
+	ccr.cc.updateResolverState(s)
+	ccr.curState = s
+}
+
+// NewAddress is called by the resolver implementation to send addresses to gRPC.
 func (ccr *ccResolverWrapper) NewAddress(addrs []resolver.Address) {
-	select {
-	case <-ccr.done:
+	if ccr.isDone() {
 		return
-	default:
 	}
 	grpclog.Infof("ccResolverWrapper: sending new addresses to cc: %v", addrs)
 	if channelz.IsOn() {
-		ccr.addChannelzTraceEvent(addrs)
+		ccr.addChannelzTraceEvent(resolver.State{Addresses: addrs, ServiceConfig: ccr.curState.ServiceConfig})
 	}
-	ccr.cc.handleResolvedAddrs(addrs, nil)
+	ccr.curState.Addresses = addrs
+	ccr.cc.updateResolverState(ccr.curState)
 }
 
-// NewServiceConfig is called by the resolver implemenetion to send service
+// NewServiceConfig is called by the resolver implementation to send service
 // configs to gRPC.
 func (ccr *ccResolverWrapper) NewServiceConfig(sc string) {
-	select {
-	case <-ccr.done:
+	if ccr.isDone() {
 		return
-	default:
 	}
 	grpclog.Infof("ccResolverWrapper: got new service config: %v", sc)
-	ccr.cc.handleServiceConfig(sc)
+	if channelz.IsOn() {
+		ccr.addChannelzTraceEvent(resolver.State{Addresses: ccr.curState.Addresses, ServiceConfig: sc})
+	}
+	ccr.curState.ServiceConfig = sc
+	ccr.cc.updateResolverState(ccr.curState)
 }
 
-func (ccr *ccResolverWrapper) addChannelzTraceEvent(addrs []resolver.Address) {
-	if len(addrs) == 0 && ccr.lastAddressesCount != 0 {
-		channelz.AddTraceEvent(ccr.cc.channelzID, &channelz.TraceEventDesc{
-			Desc:     "Resolver returns an empty address list",
-			Severity: channelz.CtWarning,
-		})
-	} else if len(addrs) != 0 && ccr.lastAddressesCount == 0 {
-		var s string
-		for i, a := range addrs {
-			if a.ServerName != "" {
-				s += a.Addr + "(" + a.ServerName + ")"
-			} else {
-				s += a.Addr
-			}
-			if i != len(addrs)-1 {
-				s += " "
-			}
-		}
-		channelz.AddTraceEvent(ccr.cc.channelzID, &channelz.TraceEventDesc{
-			Desc:     fmt.Sprintf("Resolver returns a non-empty address list (previous one was empty) %q", s),
-			Severity: channelz.CtINFO,
-		})
+func (ccr *ccResolverWrapper) addChannelzTraceEvent(s resolver.State) {
+	if s.ServiceConfig == ccr.curState.ServiceConfig && (len(ccr.curState.Addresses) == 0) == (len(s.Addresses) == 0) {
+		return
+	}
+	var updates []string
+	if s.ServiceConfig != ccr.curState.ServiceConfig {
+		updates = append(updates, "service config updated")
+	}
+	if len(ccr.curState.Addresses) > 0 && len(s.Addresses) == 0 {
+		updates = append(updates, "resolver returned an empty address list")
+	} else if len(ccr.curState.Addresses) == 0 && len(s.Addresses) > 0 {
+		updates = append(updates, "resolver returned new addresses")
 	}
-	ccr.lastAddressesCount = len(addrs)
+	channelz.AddTraceEvent(ccr.cc.channelzID, &channelz.TraceEventDesc{
+		Desc:     fmt.Sprintf("Resolver state updated: %+v (%v)", s, strings.Join(updates, "; ")),
+		Severity: channelz.CtINFO,
+	})
 }
diff --git a/vendor/google.golang.org/grpc/server.go b/vendor/google.golang.org/grpc/server.go
index 33272a47afd..8115828fdf0 100644
--- a/vendor/google.golang.org/grpc/server.go
+++ b/vendor/google.golang.org/grpc/server.go
@@ -614,12 +614,13 @@ func (s *Server) handleRawConn(rawConn net.Conn) {
 	rawConn.SetDeadline(time.Now().Add(s.opts.connectionTimeout))
 	conn, authInfo, err := s.useTransportAuthenticator(rawConn)
 	if err != nil {
-		s.mu.Lock()
-		s.errorf("ServerHandshake(%q) failed: %v", rawConn.RemoteAddr(), err)
-		s.mu.Unlock()
-		grpclog.Warningf("grpc: Server.Serve failed to complete security handshake from %q: %v", rawConn.RemoteAddr(), err)
-		// If serverHandshake returns ErrConnDispatched, keep rawConn open.
+		// ErrConnDispatched means that the connection was dispatched away from
+		// gRPC; those connections should be left open.
 		if err != credentials.ErrConnDispatched {
+			s.mu.Lock()
+			s.errorf("ServerHandshake(%q) failed: %v", rawConn.RemoteAddr(), err)
+			s.mu.Unlock()
+			grpclog.Warningf("grpc: Server.Serve failed to complete security handshake from %q: %v", rawConn.RemoteAddr(), err)
 			rawConn.Close()
 		}
 		rawConn.SetDeadline(time.Time{})
@@ -748,10 +749,11 @@ func (s *Server) traceInfo(st transport.ServerTransport, stream *transport.Strea
 
 	trInfo = &traceInfo{
 		tr: tr,
+		firstLine: firstLine{
+			client:     false,
+			remoteAddr: st.RemoteAddr(),
+		},
 	}
-	trInfo.firstLine.client = false
-	trInfo.firstLine.remoteAddr = st.RemoteAddr()
-
 	if dl, ok := stream.Context().Deadline(); ok {
 		trInfo.firstLine.deadline = time.Until(dl)
 	}
@@ -859,7 +861,6 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 	}
 	if trInfo != nil {
 		defer trInfo.tr.Finish()
-		trInfo.firstLine.client = false
 		trInfo.tr.LazyLog(&trInfo.firstLine, false)
 		defer func() {
 			if err != nil && err != io.EOF {
@@ -1245,7 +1246,8 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 	service := sm[:pos]
 	method := sm[pos+1:]
 
-	if srv, ok := s.m[service]; ok {
+	srv, knownService := s.m[service]
+	if knownService {
 		if md, ok := srv.md[method]; ok {
 			s.processUnaryRPC(t, stream, srv, md, trInfo)
 			return
@@ -1260,11 +1262,16 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 		s.processStreamingRPC(t, stream, nil, unknownDesc, trInfo)
 		return
 	}
+	var errDesc string
+	if !knownService {
+		errDesc = fmt.Sprintf("unknown service %v", service)
+	} else {
+		errDesc = fmt.Sprintf("unknown method %v for service %v", method, service)
+	}
 	if trInfo != nil {
-		trInfo.tr.LazyLog(&fmtStringer{"Unknown service %v", []interface{}{service}}, true)
+		trInfo.tr.LazyPrintf("%s", errDesc)
 		trInfo.tr.SetError()
 	}
-	errDesc := fmt.Sprintf("unknown service %v", service)
 	if err := t.WriteStatus(stream, status.New(codes.Unimplemented, errDesc)); err != nil {
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
diff --git a/vendor/google.golang.org/grpc/service_config.go b/vendor/google.golang.org/grpc/service_config.go
index 162857e204d..1c5227426f4 100644
--- a/vendor/google.golang.org/grpc/service_config.go
+++ b/vendor/google.golang.org/grpc/service_config.go
@@ -99,6 +99,9 @@ type ServiceConfig struct {
 	// healthCheckConfig must be set as one of the requirement to enable LB channel
 	// health check.
 	healthCheckConfig *healthCheckConfig
+	// rawJSONString stores service config json string that get parsed into
+	// this service config struct.
+	rawJSONString string
 }
 
 // healthCheckConfig defines the go-native version of the LB channel health check config.
@@ -238,24 +241,22 @@ type jsonSC struct {
 	HealthCheckConfig   *healthCheckConfig
 }
 
-func parseServiceConfig(js string) (ServiceConfig, error) {
-	if len(js) == 0 {
-		return ServiceConfig{}, fmt.Errorf("no JSON service config provided")
-	}
+func parseServiceConfig(js string) (*ServiceConfig, error) {
 	var rsc jsonSC
 	err := json.Unmarshal([]byte(js), &rsc)
 	if err != nil {
 		grpclog.Warningf("grpc: parseServiceConfig error unmarshaling %s due to %v", js, err)
-		return ServiceConfig{}, err
+		return nil, err
 	}
 	sc := ServiceConfig{
 		LB:                rsc.LoadBalancingPolicy,
 		Methods:           make(map[string]MethodConfig),
 		retryThrottling:   rsc.RetryThrottling,
 		healthCheckConfig: rsc.HealthCheckConfig,
+		rawJSONString:     js,
 	}
 	if rsc.MethodConfig == nil {
-		return sc, nil
+		return &sc, nil
 	}
 
 	for _, m := range *rsc.MethodConfig {
@@ -265,7 +266,7 @@ func parseServiceConfig(js string) (ServiceConfig, error) {
 		d, err := parseDuration(m.Timeout)
 		if err != nil {
 			grpclog.Warningf("grpc: parseServiceConfig error unmarshaling %s due to %v", js, err)
-			return ServiceConfig{}, err
+			return nil, err
 		}
 
 		mc := MethodConfig{
@@ -274,7 +275,7 @@ func parseServiceConfig(js string) (ServiceConfig, error) {
 		}
 		if mc.retryPolicy, err = convertRetryPolicy(m.RetryPolicy); err != nil {
 			grpclog.Warningf("grpc: parseServiceConfig error unmarshaling %s due to %v", js, err)
-			return ServiceConfig{}, err
+			return nil, err
 		}
 		if m.MaxRequestMessageBytes != nil {
 			if *m.MaxRequestMessageBytes > int64(maxInt) {
@@ -299,13 +300,13 @@ func parseServiceConfig(js string) (ServiceConfig, error) {
 
 	if sc.retryThrottling != nil {
 		if sc.retryThrottling.MaxTokens <= 0 ||
-			sc.retryThrottling.MaxTokens >= 1000 ||
+			sc.retryThrottling.MaxTokens > 1000 ||
 			sc.retryThrottling.TokenRatio <= 0 {
 			// Illegal throttling config; disable throttling.
 			sc.retryThrottling = nil
 		}
 	}
-	return sc, nil
+	return &sc, nil
 }
 
 func convertRetryPolicy(jrp *jsonRetryPolicy) (p *retryPolicy, err error) {
diff --git a/vendor/google.golang.org/grpc/stats/stats.go b/vendor/google.golang.org/grpc/stats/stats.go
index 84f77dafa58..f3f593c8443 100644
--- a/vendor/google.golang.org/grpc/stats/stats.go
+++ b/vendor/google.golang.org/grpc/stats/stats.go
@@ -27,6 +27,8 @@ import (
 	"context"
 	"net"
 	"time"
+
+	"google.golang.org/grpc/metadata"
 )
 
 // RPCStats contains stats information about RPCs.
@@ -172,6 +174,9 @@ type End struct {
 	BeginTime time.Time
 	// EndTime is the time when the RPC ends.
 	EndTime time.Time
+	// Trailer contains the trailer metadata received from the server. This
+	// field is only valid if this End is from the client side.
+	Trailer metadata.MD
 	// Error is the error the RPC ended with. It is an error generated from
 	// status.Status and can be converted back to status.Status using
 	// status.FromError if non-nil.
diff --git a/vendor/google.golang.org/grpc/stream.go b/vendor/google.golang.org/grpc/stream.go
index ccf996b4b1d..6e2bf51e0a0 100644
--- a/vendor/google.golang.org/grpc/stream.go
+++ b/vendor/google.golang.org/grpc/stream.go
@@ -33,6 +33,7 @@ import (
 	"google.golang.org/grpc/connectivity"
 	"google.golang.org/grpc/encoding"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal/balancerload"
 	"google.golang.org/grpc/internal/binarylog"
 	"google.golang.org/grpc/internal/channelz"
 	"google.golang.org/grpc/internal/grpcrand"
@@ -230,10 +231,14 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 	if c.creds != nil {
 		callHdr.Creds = c.creds
 	}
-	var trInfo traceInfo
+	var trInfo *traceInfo
 	if EnableTracing {
-		trInfo.tr = trace.New("grpc.Sent."+methodFamily(method), method)
-		trInfo.firstLine.client = true
+		trInfo = &traceInfo{
+			tr: trace.New("grpc.Sent."+methodFamily(method), method),
+			firstLine: firstLine{
+				client: true,
+			},
+		}
 		if deadline, ok := ctx.Deadline(); ok {
 			trInfo.firstLine.deadline = time.Until(deadline)
 		}
@@ -323,7 +328,7 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 	return cs, nil
 }
 
-func (cs *clientStream) newAttemptLocked(sh stats.Handler, trInfo traceInfo) error {
+func (cs *clientStream) newAttemptLocked(sh stats.Handler, trInfo *traceInfo) error {
 	cs.attempt = &csAttempt{
 		cs:           cs,
 		dc:           cs.cc.dopts.dc,
@@ -338,6 +343,9 @@ func (cs *clientStream) newAttemptLocked(sh stats.Handler, trInfo traceInfo) err
 	if err != nil {
 		return err
 	}
+	if trInfo != nil {
+		trInfo.firstLine.SetRemoteAddr(t.RemoteAddr())
+	}
 	cs.attempt.t = t
 	cs.attempt.done = done
 	return nil
@@ -414,9 +422,10 @@ type csAttempt struct {
 	decompSet bool
 
 	mu sync.Mutex // guards trInfo.tr
+	// trInfo may be nil (if EnableTracing is false).
 	// trInfo.tr is set when created (if EnableTracing is true),
 	// and cleared when the finish method is called.
-	trInfo traceInfo
+	trInfo *traceInfo
 
 	statsHandler stats.Handler
 }
@@ -540,7 +549,7 @@ func (cs *clientStream) retryLocked(lastErr error) error {
 			cs.commitAttemptLocked()
 			return err
 		}
-		if err := cs.newAttemptLocked(nil, traceInfo{}); err != nil {
+		if err := cs.newAttemptLocked(nil, nil); err != nil {
 			return err
 		}
 		if lastErr = cs.replayBufferLocked(); lastErr == nil {
@@ -811,7 +820,7 @@ func (cs *clientStream) finish(err error) {
 
 func (a *csAttempt) sendMsg(m interface{}, hdr, payld, data []byte) error {
 	cs := a.cs
-	if EnableTracing {
+	if a.trInfo != nil {
 		a.mu.Lock()
 		if a.trInfo.tr != nil {
 			a.trInfo.tr.LazyLog(&payload{sent: true, msg: m}, true)
@@ -868,7 +877,7 @@ func (a *csAttempt) recvMsg(m interface{}, payInfo *payloadInfo) (err error) {
 		}
 		return toRPCErr(err)
 	}
-	if EnableTracing {
+	if a.trInfo != nil {
 		a.mu.Lock()
 		if a.trInfo.tr != nil {
 			a.trInfo.tr.LazyLog(&payload{sent: false, msg: m}, true)
@@ -881,8 +890,9 @@ func (a *csAttempt) recvMsg(m interface{}, payInfo *payloadInfo) (err error) {
 			RecvTime: time.Now(),
 			Payload:  m,
 			// TODO truncate large payload.
-			Data:   payInfo.uncompressedBytes,
-			Length: len(payInfo.uncompressedBytes),
+			Data:       payInfo.uncompressedBytes,
+			WireLength: payInfo.wireLength,
+			Length:     len(payInfo.uncompressedBytes),
 		})
 	}
 	if channelz.IsOn() {
@@ -915,22 +925,23 @@ func (a *csAttempt) finish(err error) {
 		// Ending a stream with EOF indicates a success.
 		err = nil
 	}
+	var tr metadata.MD
 	if a.s != nil {
 		a.t.CloseStream(a.s, err)
+		tr = a.s.Trailer()
 	}
 
 	if a.done != nil {
 		br := false
-		var tr metadata.MD
 		if a.s != nil {
 			br = a.s.BytesReceived()
-			tr = a.s.Trailer()
 		}
 		a.done(balancer.DoneInfo{
 			Err:           err,
 			Trailer:       tr,
 			BytesSent:     a.s != nil,
 			BytesReceived: br,
+			ServerLoad:    balancerload.Parse(tr),
 		})
 	}
 	if a.statsHandler != nil {
@@ -938,11 +949,12 @@ func (a *csAttempt) finish(err error) {
 			Client:    true,
 			BeginTime: a.cs.beginTime,
 			EndTime:   time.Now(),
+			Trailer:   tr,
 			Error:     err,
 		}
 		a.statsHandler.HandleRPC(a.cs.ctx, end)
 	}
-	if a.trInfo.tr != nil {
+	if a.trInfo != nil && a.trInfo.tr != nil {
 		if err == nil {
 			a.trInfo.tr.LazyPrintf("RPC: [OK]")
 		} else {
@@ -1466,8 +1478,9 @@ func (ss *serverStream) RecvMsg(m interface{}) (err error) {
 			RecvTime: time.Now(),
 			Payload:  m,
 			// TODO truncate large payload.
-			Data:   payInfo.uncompressedBytes,
-			Length: len(payInfo.uncompressedBytes),
+			Data:       payInfo.uncompressedBytes,
+			WireLength: payInfo.wireLength,
+			Length:     len(payInfo.uncompressedBytes),
 		})
 	}
 	if ss.binlog != nil {
diff --git a/vendor/google.golang.org/grpc/trace.go b/vendor/google.golang.org/grpc/trace.go
index c1c96dedcb7..0a57b999481 100644
--- a/vendor/google.golang.org/grpc/trace.go
+++ b/vendor/google.golang.org/grpc/trace.go
@@ -24,6 +24,7 @@ import (
 	"io"
 	"net"
 	"strings"
+	"sync"
 	"time"
 
 	"golang.org/x/net/trace"
@@ -53,13 +54,25 @@ type traceInfo struct {
 }
 
 // firstLine is the first line of an RPC trace.
+// It may be mutated after construction; remoteAddr specifically may change
+// during client-side use.
 type firstLine struct {
+	mu         sync.Mutex
 	client     bool // whether this is a client (outgoing) RPC
 	remoteAddr net.Addr
 	deadline   time.Duration // may be zero
 }
 
+func (f *firstLine) SetRemoteAddr(addr net.Addr) {
+	f.mu.Lock()
+	f.remoteAddr = addr
+	f.mu.Unlock()
+}
+
 func (f *firstLine) String() string {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+
 	var line bytes.Buffer
 	io.WriteString(&line, "RPC: ")
 	if f.client {
diff --git a/vendor/google.golang.org/grpc/version.go b/vendor/google.golang.org/grpc/version.go
index c30e84c005f..092e088258d 100644
--- a/vendor/google.golang.org/grpc/version.go
+++ b/vendor/google.golang.org/grpc/version.go
@@ -19,4 +19,4 @@
 package grpc
 
 // Version is the current grpc version.
-const Version = "1.19.0"
+const Version = "1.20.1"