update dependencies

21 files changed, 1082 insertions, 433 deletions

diff --git a/vendor/google.golang.org/grpc/README.md b/vendor/google.golang.org/grpc/README.md
index 39120c2..4a65571 100644
--- a/vendor/google.golang.org/grpc/README.md
+++ b/vendor/google.golang.org/grpc/README.md
@@ -16,23 +16,7 @@ $ go get google.golang.org/grpc
 Prerequisites
 -------------
 
-This requires Go 1.5 or later.
-
-A note on the version used: significant performance improvements in benchmarks
-of grpc-go have been seen by upgrading the go version from 1.5 to the latest
-1.7.1.
-
-From https://golang.org/doc/install, one way to install the latest version of go is:
-```
-$ GO_VERSION=1.7.1
-$ OS=linux
-$ ARCH=amd64
-$ curl -O https://storage.googleapis.com/golang/go${GO_VERSION}.${OS}-${ARCH}.tar.gz
-$ sudo tar -C /usr/local -xzf go$GO_VERSION.$OS-$ARCH.tar.gz
-$ # Put go on the PATH, keep the usual installation dir
-$ sudo ln -s /usr/local/go/bin/go /usr/bin/go
-$ rm go$GO_VERSION.$OS-$ARCH.tar.gz
-```
+This requires Go 1.6 or later.
 
 Constraints
 -----------
diff --git a/vendor/google.golang.org/grpc/call.go b/vendor/google.golang.org/grpc/call.go
index 81b52be..13ca5b7 100644
--- a/vendor/google.golang.org/grpc/call.go
+++ b/vendor/google.golang.org/grpc/call.go
@@ -36,7 +36,6 @@ package grpc
 import (
 	"bytes"
 	"io"
-	"math"
 	"time"
 
 	"golang.org/x/net/context"
@@ -44,6 +43,7 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
@@ -73,14 +73,14 @@ func recvResponse(ctx context.Context, dopts dialOptions, t transport.ClientTran
 		}
 	}
 	for {
-		if err = recv(p, dopts.codec, stream, dopts.dc, reply, math.MaxInt32, inPayload); err != nil {
+		if err = recv(p, dopts.codec, stream, dopts.dc, reply, dopts.maxMsgSize, inPayload); err != nil {
 			if err == io.EOF {
 				break
 			}
 			return
 		}
 	}
-	if inPayload != nil && err == io.EOF && stream.StatusCode() == codes.OK {
+	if inPayload != nil && err == io.EOF && stream.Status().Code() == codes.OK {
 		// TODO in the current implementation, inTrailer may be handled before inPayload in some cases.
 		// Fix the order if necessary.
 		dopts.copts.StatsHandler.HandleRPC(ctx, inPayload)
@@ -231,7 +231,7 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 		t, put, err = cc.getTransport(ctx, gopts)
 		if err != nil {
 			// TODO(zhaoq): Probably revisit the error handling.
-			if _, ok := err.(*rpcError); ok {
+			if _, ok := status.FromError(err); ok {
 				return err
 			}
 			if err == errConnClosing || err == errConnUnavailable {
@@ -285,6 +285,6 @@ func invoke(ctx context.Context, method string, args, reply interface{}, cc *Cli
 			put()
 			put = nil
 		}
-		return Errorf(stream.StatusCode(), "%s", stream.StatusDesc())
+		return stream.Status().Err()
 	}
 }
diff --git a/vendor/google.golang.org/grpc/clientconn.go b/vendor/google.golang.org/grpc/clientconn.go
index 459ce0b..0879ef0 100644
--- a/vendor/google.golang.org/grpc/clientconn.go
+++ b/vendor/google.golang.org/grpc/clientconn.go
@@ -36,8 +36,8 @@ package grpc
 import (
 	"errors"
 	"fmt"
+	"math"
 	"net"
-	"strings"
 	"sync"
 	"time"
 
@@ -45,6 +45,7 @@ import (
 	"golang.org/x/net/trace"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/transport"
 )
@@ -78,7 +79,6 @@ var (
 	errConnClosing = errors.New("grpc: the connection is closing")
 	// errConnUnavailable indicates that the connection is unavailable.
 	errConnUnavailable = errors.New("grpc: the connection is unavailable")
-	errNoAddr          = errors.New("grpc: there is no address available to dial")
 	// minimum time to give a connection to complete
 	minConnectTimeout = 20 * time.Second
 )
@@ -86,23 +86,33 @@ var (
 // dialOptions configure a Dial call. dialOptions are set by the DialOption
 // values passed to Dial.
 type dialOptions struct {
-	unaryInt  UnaryClientInterceptor
-	streamInt StreamClientInterceptor
-	codec     Codec
-	cp        Compressor
-	dc        Decompressor
-	bs        backoffStrategy
-	balancer  Balancer
-	block     bool
-	insecure  bool
-	timeout   time.Duration
-	scChan    <-chan ServiceConfig
-	copts     transport.ConnectOptions
-}
+	unaryInt   UnaryClientInterceptor
+	streamInt  StreamClientInterceptor
+	codec      Codec
+	cp         Compressor
+	dc         Decompressor
+	bs         backoffStrategy
+	balancer   Balancer
+	block      bool
+	insecure   bool
+	timeout    time.Duration
+	scChan     <-chan ServiceConfig
+	copts      transport.ConnectOptions
+	maxMsgSize int
+}
+
+const defaultClientMaxMsgSize = math.MaxInt32
 
 // DialOption configures how we set up the connection.
 type DialOption func(*dialOptions)
 
+// WithMaxMsgSize returns a DialOption which sets the maximum message size the client can receive.
+func WithMaxMsgSize(s int) DialOption {
+	return func(o *dialOptions) {
+		o.maxMsgSize = s
+	}
+}
+
 // WithCodec returns a DialOption which sets a codec for message marshaling and unmarshaling.
 func WithCodec(c Codec) DialOption {
 	return func(o *dialOptions) {
@@ -249,6 +259,13 @@ func WithUserAgent(s string) DialOption {
 	}
 }
 
+// WithKeepaliveParams returns a DialOption that specifies keepalive paramaters for the client transport.
+func WithKeepaliveParams(kp keepalive.ClientParameters) DialOption {
+	return func(o *dialOptions) {
+		o.copts.KeepaliveParams = kp
+	}
+}
+
 // WithUnaryInterceptor returns a DialOption that specifies the interceptor for unary RPCs.
 func WithUnaryInterceptor(f UnaryClientInterceptor) DialOption {
 	return func(o *dialOptions) {
@@ -288,9 +305,18 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		conns:  make(map[Address]*addrConn),
 	}
 	cc.ctx, cc.cancel = context.WithCancel(context.Background())
+	cc.dopts.maxMsgSize = defaultClientMaxMsgSize
 	for _, opt := range opts {
 		opt(&cc.dopts)
 	}
+
+	grpcUA := "grpc-go/" + Version
+	if cc.dopts.copts.UserAgent != "" {
+		cc.dopts.copts.UserAgent += " " + grpcUA
+	} else {
+		cc.dopts.copts.UserAgent = grpcUA
+	}
+
 	if cc.dopts.timeout > 0 {
 		var cancel context.CancelFunc
 		ctx, cancel = context.WithTimeout(ctx, cc.dopts.timeout)
@@ -333,23 +359,15 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 	} else if cc.dopts.insecure && cc.dopts.copts.Authority != "" {
 		cc.authority = cc.dopts.copts.Authority
 	} else {
-		colonPos := strings.LastIndex(target, ":")
-		if colonPos == -1 {
-			colonPos = len(target)
-		}
-		cc.authority = target[:colonPos]
+		cc.authority = target
 	}
-	var ok bool
 	waitC := make(chan error, 1)
 	go func() {
-		var addrs []Address
+		defer close(waitC)
 		if cc.dopts.balancer == nil && cc.sc.LB != nil {
 			cc.dopts.balancer = cc.sc.LB
 		}
-		if cc.dopts.balancer == nil {
-			// Connect to target directly if balancer is nil.
-			addrs = append(addrs, Address{Addr: target})
-		} else {
+		if cc.dopts.balancer != nil {
 			var credsClone credentials.TransportCredentials
 			if creds != nil {
 				credsClone = creds.Clone()
@@ -362,24 +380,22 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 				return
 			}
 			ch := cc.dopts.balancer.Notify()
-			if ch == nil {
-				// There is no name resolver installed.
-				addrs = append(addrs, Address{Addr: target})
-			} else {
-				addrs, ok = <-ch
-				if !ok || len(addrs) == 0 {
-					waitC <- errNoAddr
-					return
+			if ch != nil {
+				if cc.dopts.block {
+					doneChan := make(chan struct{})
+					go cc.lbWatcher(doneChan)
+					<-doneChan
+				} else {
+					go cc.lbWatcher(nil)
 				}
-			}
-		}
-		for _, a := range addrs {
-			if err := cc.resetAddrConn(a, false, nil); err != nil {
-				waitC <- err
 				return
 			}
 		}
-		close(waitC)
+		// No balancer, or no resolver within the balancer.  Connect directly.
+		if err := cc.resetAddrConn(Address{Addr: target}, cc.dopts.block, nil); err != nil {
+			waitC <- err
+			return
+		}
 	}()
 	select {
 	case <-ctx.Done():
@@ -390,15 +406,10 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 		}
 	}
 
-	// If balancer is nil or balancer.Notify() is nil, ok will be false here.
-	// The lbWatcher goroutine will not be created.
-	if ok {
-		go cc.lbWatcher()
-	}
-
 	if cc.dopts.scChan != nil {
 		go cc.scWatcher()
 	}
+
 	return cc, nil
 }
 
@@ -449,7 +460,10 @@ type ClientConn struct {
 	conns map[Address]*addrConn
 }
 
-func (cc *ClientConn) lbWatcher() {
+// lbWatcher watches the Notify channel of the balancer in cc and manages
+// connections accordingly.  If doneChan is not nil, it is closed after the
+// first successfull connection is made.
+func (cc *ClientConn) lbWatcher(doneChan chan struct{}) {
 	for addrs := range cc.dopts.balancer.Notify() {
 		var (
 			add []Address   // Addresses need to setup connections.
@@ -476,7 +490,15 @@ func (cc *ClientConn) lbWatcher() {
 		}
 		cc.mu.Unlock()
 		for _, a := range add {
-			cc.resetAddrConn(a, true, nil)
+			if doneChan != nil {
+				err := cc.resetAddrConn(a, true, nil)
+				if err == nil {
+					close(doneChan)
+					doneChan = nil
+				}
+			} else {
+				cc.resetAddrConn(a, false, nil)
+			}
 		}
 		for _, c := range del {
 			c.tearDown(errConnDrain)
@@ -505,7 +527,7 @@ func (cc *ClientConn) scWatcher() {
 // resetAddrConn creates an addrConn for addr and adds it to cc.conns.
 // If there is an old addrConn for addr, it will be torn down, using tearDownErr as the reason.
 // If tearDownErr is nil, errConnDrain will be used instead.
-func (cc *ClientConn) resetAddrConn(addr Address, skipWait bool, tearDownErr error) error {
+func (cc *ClientConn) resetAddrConn(addr Address, block bool, tearDownErr error) error {
 	ac := &addrConn{
 		cc:    cc,
 		addr:  addr,
@@ -555,8 +577,7 @@ func (cc *ClientConn) resetAddrConn(addr Address, skipWait bool, tearDownErr err
 			stale.tearDown(tearDownErr)
 		}
 	}
-	// skipWait may overwrite the decision in ac.dopts.block.
-	if ac.dopts.block && !skipWait {
+	if block {
 		if err := ac.resetTransport(false); err != nil {
 			if err != errConnClosing {
 				// Tear down ac and delete it from cc.conns.
@@ -777,6 +798,8 @@ func (ac *addrConn) resetTransport(closeTransport bool) error {
 			Metadata: ac.addr.Metadata,
 		}
 		newTransport, err := transport.NewClientTransport(ctx, sinfo, ac.dopts.copts)
+		// Don't call cancel in success path due to a race in Go 1.6:
+		// https://github.com/golang/go/issues/15078.
 		if err != nil {
 			cancel()
 
@@ -855,9 +878,9 @@ func (ac *addrConn) transportMonitor() {
 			// In both cases, a new ac is created.
 			select {
 			case <-t.Error():
-				ac.cc.resetAddrConn(ac.addr, true, errNetworkIO)
+				ac.cc.resetAddrConn(ac.addr, false, errNetworkIO)
 			default:
-				ac.cc.resetAddrConn(ac.addr, true, errConnDrain)
+				ac.cc.resetAddrConn(ac.addr, false, errConnDrain)
 			}
 			return
 		case <-t.Error():
@@ -866,7 +889,7 @@ func (ac *addrConn) transportMonitor() {
 				t.Close()
 				return
 			case <-t.GoAway():
-				ac.cc.resetAddrConn(ac.addr, true, errNetworkIO)
+				ac.cc.resetAddrConn(ac.addr, false, errNetworkIO)
 				return
 			default:
 			}
diff --git a/vendor/google.golang.org/grpc/credentials/credentials.go b/vendor/google.golang.org/grpc/credentials/credentials.go
index 4d45c3e..a8114d6 100644
--- a/vendor/google.golang.org/grpc/credentials/credentials.go
+++ b/vendor/google.golang.org/grpc/credentials/credentials.go
@@ -102,6 +102,10 @@ type TransportCredentials interface {
 	// authentication protocol on rawConn for clients. It returns the authenticated
 	// connection and the corresponding auth information about the connection.
 	// Implementations must use the provided context to implement timely cancellation.
+	// gRPC will try to reconnect if the error returned is a temporary error
+	// (io.EOF, context.DeadlineExceeded or err.Temporary() == true).
+	// If the returned error is a wrapper error, implementations should make sure that
+	// the error implements Temporary() to have the correct retry behaviors.
 	ClientHandshake(context.Context, string, net.Conn) (net.Conn, AuthInfo, error)
 	// ServerHandshake does the authentication handshake for servers. It returns
 	// the authenticated connection and the corresponding auth information about
diff --git a/vendor/google.golang.org/grpc/credentials/credentials_util_go17.go b/vendor/google.golang.org/grpc/credentials/credentials_util_go17.go
index 9647b9e..7597b09 100644
--- a/vendor/google.golang.org/grpc/credentials/credentials_util_go17.go
+++ b/vendor/google.golang.org/grpc/credentials/credentials_util_go17.go
@@ -1,4 +1,5 @@
 // +build go1.7
+// +build !go1.8
 
 /*
  *
@@ -44,8 +45,6 @@ import (
 // contains a mutex and must not be copied.
 //
 // If cfg is nil, a new zero tls.Config is returned.
-//
-// TODO replace this function with official clone function.
 func cloneTLSConfig(cfg *tls.Config) *tls.Config {
 	if cfg == nil {
 		return &tls.Config{}
diff --git a/vendor/google.golang.org/grpc/transport/pre_go16.go b/vendor/google.golang.org/grpc/credentials/credentials_util_go18.go
index 33d91c1..0ecf342 100644
--- a/vendor/google.golang.org/grpc/transport/pre_go16.go
+++ b/vendor/google.golang.org/grpc/credentials/credentials_util_go18.go
@@ -1,7 +1,8 @@
-// +build !go1.6
+// +build go1.8
 
 /*
- * Copyright 2016, Google Inc.
+ *
+ * Copyright 2017, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -32,20 +33,21 @@
  *
  */
 
-package transport
+package credentials
 
 import (
-	"net"
-	"time"
-
-	"golang.org/x/net/context"
+	"crypto/tls"
 )
 
-// dialContext connects to the address on the named network.
-func dialContext(ctx context.Context, network, address string) (net.Conn, error) {
-	var dialer net.Dialer
-	if deadline, ok := ctx.Deadline(); ok {
-		dialer.Timeout = deadline.Sub(time.Now())
+// cloneTLSConfig returns a shallow clone of the exported
+// fields of cfg, ignoring the unexported sync.Once, which
+// contains a mutex and must not be copied.
+//
+// If cfg is nil, a new zero tls.Config is returned.
+func cloneTLSConfig(cfg *tls.Config) *tls.Config {
+	if cfg == nil {
+		return &tls.Config{}
 	}
-	return dialer.Dial(network, address)
+
+	return cfg.Clone()
 }
diff --git a/vendor/google.golang.org/grpc/credentials/credentials_util_pre_go17.go b/vendor/google.golang.org/grpc/credentials/credentials_util_pre_go17.go
index 09b8d12..cfd40df 100644
--- a/vendor/google.golang.org/grpc/credentials/credentials_util_pre_go17.go
+++ b/vendor/google.golang.org/grpc/credentials/credentials_util_pre_go17.go
@@ -44,8 +44,6 @@ import (
 // contains a mutex and must not be copied.
 //
 // If cfg is nil, a new zero tls.Config is returned.
-//
-// TODO replace this function with official clone function.
 func cloneTLSConfig(cfg *tls.Config) *tls.Config {
 	if cfg == nil {
 		return &tls.Config{}
diff --git a/vendor/google.golang.org/grpc/interceptor.go b/vendor/google.golang.org/grpc/interceptor.go
index 8d932ef..a692161 100644
--- a/vendor/google.golang.org/grpc/interceptor.go
+++ b/vendor/google.golang.org/grpc/interceptor.go
@@ -40,7 +40,7 @@ import (
 // UnaryInvoker is called by UnaryClientInterceptor to complete RPCs.
 type UnaryInvoker func(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, opts ...CallOption) error
 
-// UnaryClientInterceptor intercepts the execution of a unary RPC on the client. inovker is the handler to complete the RPC
+// UnaryClientInterceptor intercepts the execution of a unary RPC on the client. invoker is the handler to complete the RPC
 // and it is the responsibility of the interceptor to call it.
 // This is the EXPERIMENTAL API.
 type UnaryClientInterceptor func(ctx context.Context, method string, req, reply interface{}, cc *ClientConn, invoker UnaryInvoker, opts ...CallOption) error
diff --git a/vendor/google.golang.org/grpc/keepalive/keepalive.go b/vendor/google.golang.org/grpc/keepalive/keepalive.go
new file mode 100644
index 0000000..d492589
--- /dev/null
+++ b/vendor/google.golang.org/grpc/keepalive/keepalive.go
@@ -0,0 +1,80 @@
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+// Package keepalive defines configurable parameters for point-to-point healthcheck.
+package keepalive
+
+import (
+	"time"
+)
+
+// ClientParameters is used to set keepalive parameters on the client-side.
+// These configure how the client will actively probe to notice when a connection broken
+// and to cause activity so intermediaries are aware the connection is still in use.
+// Make sure these parameters are set in coordination with the keepalive policy on the server,
+// as incompatible settings can result in closing of connection.
+type ClientParameters struct {
+	// After a duration of this time if the client doesn't see any activity it pings the server to see if the transport is still alive.
+	Time time.Duration // The current default value is infinity.
+	// After having pinged for keepalive check, the client waits for a duration of Timeout and if no activity is seen even after that
+	// the connection is closed.
+	Timeout time.Duration // The current default value is 20 seconds.
+	// If true, client runs keepalive checks even with no active RPCs.
+	PermitWithoutStream bool // false by default.
+}
+
+// ServerParameters is used to set keepalive and max-age parameters on the server-side.
+type ServerParameters struct {
+	// MaxConnectionIdle is a duration for the amount of time after which an idle connection would be closed by sending a GoAway.
+	// Idleness duration is defined since the most recent time the number of outstanding RPCs became zero or the connection establishment.
+	MaxConnectionIdle time.Duration // The current default value is infinity.
+	// MaxConnectionAge is a duration for the maximum amount of time a connection may exist before it will be closed by sending a GoAway.
+	// A random jitter of +/-10% will be added to MaxConnectionAge to spread out connection storms.
+	MaxConnectionAge time.Duration // The current default value is infinity.
+	// MaxConnectinoAgeGrace is an additive period after MaxConnectionAge after which the connection will be forcibly closed.
+	MaxConnectionAgeGrace time.Duration // The current default value is infinity.
+	// After a duration of this time if the server doesn't see any activity it pings the client to see if the transport is still alive.
+	Time time.Duration // The current default value is 2 hours.
+	// After having pinged for keepalive check, the server waits for a duration of Timeout and if no activity is seen even after that
+	// the connection is closed.
+	Timeout time.Duration // The current default value is 20 seconds.
+}
+
+// EnforcementPolicy is used to set keepalive enforcement policy on the server-side.
+// Server will close connection with a client that violates this policy.
+type EnforcementPolicy struct {
+	// MinTime is the minimum amount of time a client should wait before sending a keepalive ping.
+	MinTime time.Duration // The current default value is 5 minutes.
+	// If true, server expects keepalive pings even when there are no active streams(RPCs).
+	PermitWithoutStream bool // false by default.
+}
diff --git a/vendor/google.golang.org/grpc/metadata/metadata.go b/vendor/google.golang.org/grpc/metadata/metadata.go
index 7332395..7ca4418 100644
--- a/vendor/google.golang.org/grpc/metadata/metadata.go
+++ b/vendor/google.golang.org/grpc/metadata/metadata.go
@@ -136,17 +136,41 @@ func Join(mds ...MD) MD {
 	return out
 }
 
-type mdKey struct{}
+type mdIncomingKey struct{}
+type mdOutgoingKey struct{}
 
-// NewContext creates a new context with md attached.
+// NewContext is a wrapper for NewOutgoingContext(ctx, md).  Deprecated.
 func NewContext(ctx context.Context, md MD) context.Context {
-	return context.WithValue(ctx, mdKey{}, md)
+	return NewOutgoingContext(ctx, md)
 }
 
-// FromContext returns the MD in ctx if it exists.
-// The returned md should be immutable, writing to it may cause races.
-// Modification should be made to the copies of the returned md.
+// NewIncomingContext creates a new context with incoming md attached.
+func NewIncomingContext(ctx context.Context, md MD) context.Context {
+	return context.WithValue(ctx, mdIncomingKey{}, md)
+}
+
+// NewOutgoingContext creates a new context with outgoing md attached.
+func NewOutgoingContext(ctx context.Context, md MD) context.Context {
+	return context.WithValue(ctx, mdOutgoingKey{}, md)
+}
+
+// FromContext is a wrapper for FromIncomingContext(ctx).  Deprecated.
 func FromContext(ctx context.Context) (md MD, ok bool) {
-	md, ok = ctx.Value(mdKey{}).(MD)
+	return FromIncomingContext(ctx)
+}
+
+// FromIncomingContext returns the incoming MD in ctx if it exists.  The
+// returned md should be immutable, writing to it may cause races.
+// Modification should be made to the copies of the returned md.
+func FromIncomingContext(ctx context.Context) (md MD, ok bool) {
+	md, ok = ctx.Value(mdIncomingKey{}).(MD)
+	return
+}
+
+// FromOutgoingContext returns the outgoing MD in ctx if it exists.  The
+// returned md should be immutable, writing to it may cause races.
+// Modification should be made to the copies of the returned md.
+func FromOutgoingContext(ctx context.Context) (md MD, ok bool) {
+	md, ok = ctx.Value(mdOutgoingKey{}).(MD)
 	return
 }
diff --git a/vendor/google.golang.org/grpc/rpc_util.go b/vendor/google.golang.org/grpc/rpc_util.go
index d98a883..db56a88 100644
--- a/vendor/google.golang.org/grpc/rpc_util.go
+++ b/vendor/google.golang.org/grpc/rpc_util.go
@@ -37,7 +37,6 @@ import (
 	"bytes"
 	"compress/gzip"
 	"encoding/binary"
-	"fmt"
 	"io"
 	"io/ioutil"
 	"math"
@@ -50,6 +49,7 @@ import (
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
@@ -189,7 +189,9 @@ func Trailer(md *metadata.MD) CallOption {
 // unary RPC.
 func Peer(peer *peer.Peer) CallOption {
 	return afterCall(func(c *callInfo) {
-		*peer = *c.peer
+		if c.peer != nil {
+			*peer = *c.peer
+		}
 	})
 }
 
@@ -370,88 +372,57 @@ func recv(p *parser, c Codec, s *transport.Stream, dc Decompressor, m interface{
 	return nil
 }
 
-// rpcError defines the status from an RPC.
-type rpcError struct {
-	code codes.Code
-	desc string
-}
-
-func (e *rpcError) Error() string {
-	return fmt.Sprintf("rpc error: code = %d desc = %s", e.code, e.desc)
-}
-
 // Code returns the error code for err if it was produced by the rpc system.
 // Otherwise, it returns codes.Unknown.
+//
+// Deprecated; use status.FromError and Code method instead.
 func Code(err error) codes.Code {
-	if err == nil {
-		return codes.OK
-	}
-	if e, ok := err.(*rpcError); ok {
-		return e.code
+	if s, ok := status.FromError(err); ok {
+		return s.Code()
 	}
 	return codes.Unknown
 }
 
 // ErrorDesc returns the error description of err if it was produced by the rpc system.
 // Otherwise, it returns err.Error() or empty string when err is nil.
+//
+// Deprecated; use status.FromError and Message method instead.
 func ErrorDesc(err error) string {
-	if err == nil {
-		return ""
-	}
-	if e, ok := err.(*rpcError); ok {
-		return e.desc
+	if s, ok := status.FromError(err); ok {
+		return s.Message()
 	}
 	return err.Error()
 }
 
 // Errorf returns an error containing an error code and a description;
 // Errorf returns nil if c is OK.
+//
+// Deprecated; use status.Errorf instead.
 func Errorf(c codes.Code, format string, a ...interface{}) error {
-	if c == codes.OK {
-		return nil
-	}
-	return &rpcError{
-		code: c,
-		desc: fmt.Sprintf(format, a...),
-	}
+	return status.Errorf(c, format, a...)
 }
 
-// toRPCErr converts an error into a rpcError.
+// toRPCErr converts an error into an error from the status package.
 func toRPCErr(err error) error {
-	switch e := err.(type) {
-	case *rpcError:
+	if _, ok := status.FromError(err); ok {
 		return err
+	}
+	switch e := err.(type) {
 	case transport.StreamError:
-		return &rpcError{
-			code: e.Code,
-			desc: e.Desc,
-		}
+		return status.Error(e.Code, e.Desc)
 	case transport.ConnectionError:
-		return &rpcError{
-			code: codes.Internal,
-			desc: e.Desc,
-		}
+		return status.Error(codes.Internal, e.Desc)
 	default:
 		switch err {
 		case context.DeadlineExceeded:
-			return &rpcError{
-				code: codes.DeadlineExceeded,
-				desc: err.Error(),
-			}
+			return status.Error(codes.DeadlineExceeded, err.Error())
 		case context.Canceled:
-			return &rpcError{
-				code: codes.Canceled,
-				desc: err.Error(),
-			}
+			return status.Error(codes.Canceled, err.Error())
 		case ErrClientConnClosing:
-			return &rpcError{
-				code: codes.FailedPrecondition,
-				desc: err.Error(),
-			}
+			return status.Error(codes.FailedPrecondition, err.Error())
 		}
-
 	}
-	return Errorf(codes.Unknown, "%v", err)
+	return status.Error(codes.Unknown, err.Error())
 }
 
 // convertCode converts a standard Go error into its canonical code. Note that
@@ -527,3 +498,6 @@ type ServiceConfig struct {
 // requires a synchronised update of grpc-go and protoc-gen-go. This constant
 // should not be referenced from any other code.
 const SupportPackageIsVersion4 = true
+
+// Version is the current grpc version.
+const Version = "1.3.0-dev"
diff --git a/vendor/google.golang.org/grpc/server.go b/vendor/google.golang.org/grpc/server.go
index 985226d..b15f71c 100644
--- a/vendor/google.golang.org/grpc/server.go
+++ b/vendor/google.golang.org/grpc/server.go
@@ -53,8 +53,10 @@ import (
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/tap"
 	"google.golang.org/grpc/transport"
 )
@@ -116,6 +118,9 @@ type options struct {
 	statsHandler         stats.Handler
 	maxConcurrentStreams uint32
 	useHandlerImpl       bool // use http.Handler-based server
+	unknownStreamDesc    *StreamDesc
+	keepaliveParams      keepalive.ServerParameters
+	keepalivePolicy      keepalive.EnforcementPolicy
 }
 
 var defaultMaxMsgSize = 1024 * 1024 * 4 // use 4MB as the default message size limit
@@ -123,6 +128,20 @@ var defaultMaxMsgSize = 1024 * 1024 * 4 // use 4MB as the default message size l
 // A ServerOption sets options.
 type ServerOption func(*options)
 
+// KeepaliveParams returns a ServerOption that sets keepalive and max-age parameters for the server.
+func KeepaliveParams(kp keepalive.ServerParameters) ServerOption {
+	return func(o *options) {
+		o.keepaliveParams = kp
+	}
+}
+
+// KeepaliveEnforcementPolicy returns a ServerOption that sets keepalive enforcement policy for the server.
+func KeepaliveEnforcementPolicy(kep keepalive.EnforcementPolicy) ServerOption {
+	return func(o *options) {
+		o.keepalivePolicy = kep
+	}
+}
+
 // CustomCodec returns a ServerOption that sets a codec for message marshaling and unmarshaling.
 func CustomCodec(codec Codec) ServerOption {
 	return func(o *options) {
@@ -208,6 +227,24 @@ func StatsHandler(h stats.Handler) ServerOption {
 	}
 }
 
+// UnknownServiceHandler returns a ServerOption that allows for adding a custom
+// unknown service handler. The provided method is a bidi-streaming RPC service
+// handler that will be invoked instead of returning the the "unimplemented" gRPC
+// error whenever a request is received for an unregistered service or method.
+// The handling function has full access to the Context of the request and the
+// stream, and the invocation passes through interceptors.
+func UnknownServiceHandler(streamHandler StreamHandler) ServerOption {
+	return func(o *options) {
+		o.unknownStreamDesc = &StreamDesc{
+			StreamName: "unknown_service_handler",
+			Handler:    streamHandler,
+			// We need to assume that the users of the streamHandler will want to use both.
+			ClientStreams: true,
+			ServerStreams: true,
+		}
+	}
+}
+
 // NewServer creates a gRPC server which has no service registered and has not
 // started to accept requests yet.
 func NewServer(opt ...ServerOption) *Server {
@@ -446,10 +483,12 @@ func (s *Server) handleRawConn(rawConn net.Conn) {
 // transport.NewServerTransport).
 func (s *Server) serveHTTP2Transport(c net.Conn, authInfo credentials.AuthInfo) {
 	config := &transport.ServerConfig{
-		MaxStreams:   s.opts.maxConcurrentStreams,
-		AuthInfo:     authInfo,
-		InTapHandle:  s.opts.inTapHandle,
-		StatsHandler: s.opts.statsHandler,
+		MaxStreams:      s.opts.maxConcurrentStreams,
+		AuthInfo:        authInfo,
+		InTapHandle:     s.opts.inTapHandle,
+		StatsHandler:    s.opts.statsHandler,
+		KeepaliveParams: s.opts.keepaliveParams,
+		KeepalivePolicy: s.opts.keepalivePolicy,
 	}
 	st, err := transport.NewServerTransport("http2", c, config)
 	if err != nil {
@@ -633,7 +672,7 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 		stream.SetSendCompress(s.opts.cp.Type())
 	}
 	p := &parser{r: stream}
-	for {
+	for { // TODO: delete
 		pf, req, err := p.recvMsg(s.opts.maxMsgSize)
 		if err == io.EOF {
 			// The entire stream is done (for unary RPC only).
@@ -643,36 +682,37 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 			err = Errorf(codes.Internal, io.ErrUnexpectedEOF.Error())
 		}
 		if err != nil {
-			switch err := err.(type) {
-			case *rpcError:
-				if e := t.WriteStatus(stream, err.code, err.desc); e != nil {
+			if st, ok := status.FromError(err); ok {
+				if e := t.WriteStatus(stream, st); e != nil {
 					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
 				}
-			case transport.ConnectionError:
-				// Nothing to do here.
-			case transport.StreamError:
-				if e := t.WriteStatus(stream, err.Code, err.Desc); e != nil {
-					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
+			} else {
+				switch st := err.(type) {
+				case transport.ConnectionError:
+					// Nothing to do here.
+				case transport.StreamError:
+					if e := t.WriteStatus(stream, status.New(st.Code, st.Desc)); e != nil {
+						grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
+					}
+				default:
+					panic(fmt.Sprintf("grpc: Unexpected error (%T) from recvMsg: %v", st, st))
 				}
-			default:
-				panic(fmt.Sprintf("grpc: Unexpected error (%T) from recvMsg: %v", err, err))
 			}
 			return err
 		}
 
 		if err := checkRecvPayload(pf, stream.RecvCompress(), s.opts.dc); err != nil {
-			switch err := err.(type) {
-			case *rpcError:
-				if e := t.WriteStatus(stream, err.code, err.desc); e != nil {
+			if st, ok := status.FromError(err); ok {
+				if e := t.WriteStatus(stream, st); e != nil {
 					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
 				}
 				return err
-			default:
-				if e := t.WriteStatus(stream, codes.Internal, err.Error()); e != nil {
-					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
-				}
-				// TODO checkRecvPayload always return RPC error. Add a return here if necessary.
 			}
+			if e := t.WriteStatus(stream, status.New(codes.Internal, err.Error())); e != nil {
+				grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
+			}
+
+			// TODO checkRecvPayload always return RPC error. Add a return here if necessary.
 		}
 		var inPayload *stats.InPayload
 		if sh != nil {
@@ -680,8 +720,6 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 				RecvTime: time.Now(),
 			}
 		}
-		statusCode := codes.OK
-		statusDesc := ""
 		df := func(v interface{}) error {
 			if inPayload != nil {
 				inPayload.WireLength = len(req)
@@ -690,20 +728,16 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 				var err error
 				req, err = s.opts.dc.Do(bytes.NewReader(req))
 				if err != nil {
-					if err := t.WriteStatus(stream, codes.Internal, err.Error()); err != nil {
-						grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", err)
-					}
 					return Errorf(codes.Internal, err.Error())
 				}
 			}
 			if len(req) > s.opts.maxMsgSize {
 				// TODO: Revisit the error code. Currently keep it consistent with
 				// java implementation.
-				statusCode = codes.Internal
-				statusDesc = fmt.Sprintf("grpc: server received a message of %d bytes exceeding %d limit", len(req), s.opts.maxMsgSize)
+				return status.Errorf(codes.Internal, "grpc: server received a message of %d bytes exceeding %d limit", len(req), s.opts.maxMsgSize)
 			}
 			if err := s.opts.codec.Unmarshal(req, v); err != nil {
-				return err
+				return status.Errorf(codes.Internal, "grpc: error unmarshalling request: %v", err)
 			}
 			if inPayload != nil {
 				inPayload.Payload = v
@@ -718,21 +752,20 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 		}
 		reply, appErr := md.Handler(srv.server, stream.Context(), df, s.opts.unaryInt)
 		if appErr != nil {
-			if err, ok := appErr.(*rpcError); ok {
-				statusCode = err.code
-				statusDesc = err.desc
-			} else {
-				statusCode = convertCode(appErr)
-				statusDesc = appErr.Error()
+			appStatus, ok := status.FromError(appErr)
+			if !ok {
+				// Convert appErr if it is not a grpc status error.
+				appErr = status.Error(convertCode(appErr), appErr.Error())
+				appStatus, _ = status.FromError(appErr)
 			}
-			if trInfo != nil && statusCode != codes.OK {
-				trInfo.tr.LazyLog(stringer(statusDesc), true)
+			if trInfo != nil {
+				trInfo.tr.LazyLog(stringer(appStatus.Message()), true)
 				trInfo.tr.SetError()
 			}
-			if err := t.WriteStatus(stream, statusCode, statusDesc); err != nil {
-				grpclog.Printf("grpc: Server.processUnaryRPC failed to write status: %v", err)
+			if e := t.WriteStatus(stream, appStatus); e != nil {
+				grpclog.Printf("grpc: Server.processUnaryRPC failed to write status: %v", e)
 			}
-			return Errorf(statusCode, statusDesc)
+			return appErr
 		}
 		if trInfo != nil {
 			trInfo.tr.LazyLog(stringer("OK"), false)
@@ -742,26 +775,35 @@ func (s *Server) processUnaryRPC(t transport.ServerTransport, stream *transport.
 			Delay: false,
 		}
 		if err := s.sendResponse(t, stream, reply, s.opts.cp, opts); err != nil {
-			switch err := err.(type) {
-			case transport.ConnectionError:
-				// Nothing to do here.
-			case transport.StreamError:
-				statusCode = err.Code
-				statusDesc = err.Desc
-			default:
-				statusCode = codes.Unknown
-				statusDesc = err.Error()
+			if err == io.EOF {
+				// The entire stream is done (for unary RPC only).
+				return err
+			}
+			if s, ok := status.FromError(err); ok {
+				if e := t.WriteStatus(stream, s); e != nil {
+					grpclog.Printf("grpc: Server.processUnaryRPC failed to write status: %v", e)
+				}
+			} else {
+				switch st := err.(type) {
+				case transport.ConnectionError:
+					// Nothing to do here.
+				case transport.StreamError:
+					if e := t.WriteStatus(stream, status.New(st.Code, st.Desc)); e != nil {
+						grpclog.Printf("grpc: Server.processUnaryRPC failed to write status %v", e)
+					}
+				default:
+					panic(fmt.Sprintf("grpc: Unexpected error (%T) from sendResponse: %v", st, st))
+				}
 			}
 			return err
 		}
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&payload{sent: true, msg: reply}, true)
 		}
-		errWrite := t.WriteStatus(stream, statusCode, statusDesc)
-		if statusCode != codes.OK {
-			return Errorf(statusCode, statusDesc)
-		}
-		return errWrite
+		// TODO: Should we be logging if writing status failed here, like above?
+		// Should the logging be in WriteStatus?  Should we ignore the WriteStatus
+		// error or allow the stats handler to see it?
+		return t.WriteStatus(stream, status.New(codes.OK, ""))
 	}
 }
 
@@ -815,43 +857,47 @@ func (s *Server) processStreamingRPC(t transport.ServerTransport, stream *transp
 		}()
 	}
 	var appErr error
+	var server interface{}
+	if srv != nil {
+		server = srv.server
+	}
 	if s.opts.streamInt == nil {
-		appErr = sd.Handler(srv.server, ss)
+		appErr = sd.Handler(server, ss)
 	} else {
 		info := &StreamServerInfo{
 			FullMethod:     stream.Method(),
 			IsClientStream: sd.ClientStreams,
 			IsServerStream: sd.ServerStreams,
 		}
-		appErr = s.opts.streamInt(srv.server, ss, info, sd.Handler)
+		appErr = s.opts.streamInt(server, ss, info, sd.Handler)
 	}
 	if appErr != nil {
-		if err, ok := appErr.(*rpcError); ok {
-			ss.statusCode = err.code
-			ss.statusDesc = err.desc
-		} else if err, ok := appErr.(transport.StreamError); ok {
-			ss.statusCode = err.Code
-			ss.statusDesc = err.Desc
-		} else {
-			ss.statusCode = convertCode(appErr)
-			ss.statusDesc = appErr.Error()
+		appStatus, ok := status.FromError(appErr)
+		if !ok {
+			switch err := appErr.(type) {
+			case transport.StreamError:
+				appStatus = status.New(err.Code, err.Desc)
+			default:
+				appStatus = status.New(convertCode(appErr), appErr.Error())
+			}
+			appErr = appStatus.Err()
+		}
+		if trInfo != nil {
+			ss.mu.Lock()
+			ss.trInfo.tr.LazyLog(stringer(appStatus.Message()), true)
+			ss.trInfo.tr.SetError()
+			ss.mu.Unlock()
 		}
+		t.WriteStatus(ss.s, appStatus)
+		// TODO: Should we log an error from WriteStatus here and below?
+		return appErr
 	}
 	if trInfo != nil {
 		ss.mu.Lock()
-		if ss.statusCode != codes.OK {
-			ss.trInfo.tr.LazyLog(stringer(ss.statusDesc), true)
-			ss.trInfo.tr.SetError()
-		} else {
-			ss.trInfo.tr.LazyLog(stringer("OK"), false)
-		}
+		ss.trInfo.tr.LazyLog(stringer("OK"), false)
 		ss.mu.Unlock()
 	}
-	errWrite := t.WriteStatus(ss.s, ss.statusCode, ss.statusDesc)
-	if ss.statusCode != codes.OK {
-		return Errorf(ss.statusCode, ss.statusDesc)
-	}
-	return errWrite
+	return t.WriteStatus(ss.s, status.New(codes.OK, ""))
 
 }
 
@@ -867,7 +913,7 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 			trInfo.tr.SetError()
 		}
 		errDesc := fmt.Sprintf("malformed method name: %q", stream.Method())
-		if err := t.WriteStatus(stream, codes.InvalidArgument, errDesc); err != nil {
+		if err := t.WriteStatus(stream, status.New(codes.InvalidArgument, errDesc)); err != nil {
 			if trInfo != nil {
 				trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
 				trInfo.tr.SetError()
@@ -883,12 +929,16 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 	method := sm[pos+1:]
 	srv, ok := s.m[service]
 	if !ok {
+		if unknownDesc := s.opts.unknownStreamDesc; unknownDesc != nil {
+			s.processStreamingRPC(t, stream, nil, unknownDesc, trInfo)
+			return
+		}
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&fmtStringer{"Unknown service %v", []interface{}{service}}, true)
 			trInfo.tr.SetError()
 		}
 		errDesc := fmt.Sprintf("unknown service %v", service)
-		if err := t.WriteStatus(stream, codes.Unimplemented, errDesc); err != nil {
+		if err := t.WriteStatus(stream, status.New(codes.Unimplemented, errDesc)); err != nil {
 			if trInfo != nil {
 				trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
 				trInfo.tr.SetError()
@@ -913,8 +963,12 @@ func (s *Server) handleStream(t transport.ServerTransport, stream *transport.Str
 		trInfo.tr.LazyLog(&fmtStringer{"Unknown method %v", []interface{}{method}}, true)
 		trInfo.tr.SetError()
 	}
+	if unknownDesc := s.opts.unknownStreamDesc; unknownDesc != nil {
+		s.processStreamingRPC(t, stream, nil, unknownDesc, trInfo)
+		return
+	}
 	errDesc := fmt.Sprintf("unknown method %v", method)
-	if err := t.WriteStatus(stream, codes.Unimplemented, errDesc); err != nil {
+	if err := t.WriteStatus(stream, status.New(codes.Unimplemented, errDesc)); err != nil {
 		if trInfo != nil {
 			trInfo.tr.LazyLog(&fmtStringer{"%v", []interface{}{err}}, true)
 			trInfo.tr.SetError()
diff --git a/vendor/google.golang.org/grpc/stats/stats.go b/vendor/google.golang.org/grpc/stats/stats.go
index a82448a..43d6f00 100644
--- a/vendor/google.golang.org/grpc/stats/stats.go
+++ b/vendor/google.golang.org/grpc/stats/stats.go
@@ -184,7 +184,7 @@ type End struct {
 	Client bool
 	// EndTime is the time when the RPC ends.
 	EndTime time.Time
-	// Error is the error just happened. Its type is gRPC error.
+	// Error is the error just happened.  It implements status.Status if non-nil.
 	Error error
 }
 
diff --git a/vendor/google.golang.org/grpc/status/status.go b/vendor/google.golang.org/grpc/status/status.go
new file mode 100644
index 0000000..99f1a09
--- /dev/null
+++ b/vendor/google.golang.org/grpc/status/status.go
@@ -0,0 +1,136 @@
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+// Package status implements errors returned by gRPC.  These errors are
+// serialized and transmitted on the wire between server and client, and allow
+// for additional data to be transmitted via the Details field in the status
+// proto.  gRPC service handlers should return an error created by this
+// package, and gRPC clients should expect a corresponding error to be
+// returned from the RPC call.
+//
+// This package upholds the invariants that a non-nil error may not
+// contain an OK code, and an OK code must result in a nil error.
+package status
+
+import (
+	"fmt"
+
+	"github.com/golang/protobuf/proto"
+	spb "google.golang.org/genproto/googleapis/rpc/status"
+	"google.golang.org/grpc/codes"
+)
+
+// statusError is an alias of a status proto.  It implements error and Status,
+// and a nil statusError should never be returned by this package.
+type statusError spb.Status
+
+func (se *statusError) Error() string {
+	p := (*spb.Status)(se)
+	return fmt.Sprintf("rpc error: code = %s desc = %s", codes.Code(p.GetCode()), p.GetMessage())
+}
+
+func (se *statusError) status() *Status {
+	return &Status{s: (*spb.Status)(se)}
+}
+
+// Status represents an RPC status code, message, and details.  It is immutable
+// and should be created with New, Newf, or FromProto.
+type Status struct {
+	s *spb.Status
+}
+
+// Code returns the status code contained in s.
+func (s *Status) Code() codes.Code {
+	return codes.Code(s.s.Code)
+}
+
+// Message returns the message contained in s.
+func (s *Status) Message() string {
+	return s.s.Message
+}
+
+// Proto returns s's status as an spb.Status proto message.
+func (s *Status) Proto() *spb.Status {
+	return proto.Clone(s.s).(*spb.Status)
+}
+
+// Err returns an immutable error representing s; returns nil if s.Code() is
+// OK.
+func (s *Status) Err() error {
+	if s.Code() == codes.OK {
+		return nil
+	}
+	return (*statusError)(s.s)
+}
+
+// New returns a Status representing c and msg.
+func New(c codes.Code, msg string) *Status {
+	return &Status{s: &spb.Status{Code: int32(c), Message: msg}}
+}
+
+// Newf returns New(c, fmt.Sprintf(format, a...)).
+func Newf(c codes.Code, format string, a ...interface{}) *Status {
+	return New(c, fmt.Sprintf(format, a...))
+}
+
+// Error returns an error representing c and msg.  If c is OK, returns nil.
+func Error(c codes.Code, msg string) error {
+	return New(c, msg).Err()
+}
+
+// Errorf returns Error(c, fmt.Sprintf(format, a...)).
+func Errorf(c codes.Code, format string, a ...interface{}) error {
+	return Error(c, fmt.Sprintf(format, a...))
+}
+
+// ErrorProto returns an error representing s.  If s.Code is OK, returns nil.
+func ErrorProto(s *spb.Status) error {
+	return FromProto(s).Err()
+}
+
+// FromProto returns a Status representing s.
+func FromProto(s *spb.Status) *Status {
+	return &Status{s: proto.Clone(s).(*spb.Status)}
+}
+
+// FromError returns a Status representing err if it was produced from this
+// package, otherwise it returns nil, false.
+func FromError(err error) (s *Status, ok bool) {
+	if err == nil {
+		return &Status{s: &spb.Status{Code: int32(codes.OK)}}, true
+	}
+	if s, ok := err.(*statusError); ok {
+		return s.status(), true
+	}
+	return nil, false
+}
diff --git a/vendor/google.golang.org/grpc/stream.go b/vendor/google.golang.org/grpc/stream.go
index bb468dc..ecb1a31 100644
--- a/vendor/google.golang.org/grpc/stream.go
+++ b/vendor/google.golang.org/grpc/stream.go
@@ -37,7 +37,6 @@ import (
 	"bytes"
 	"errors"
 	"io"
-	"math"
 	"sync"
 	"time"
 
@@ -46,6 +45,7 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/transport"
 )
 
@@ -178,7 +178,7 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		t, put, err = cc.getTransport(ctx, gopts)
 		if err != nil {
 			// TODO(zhaoq): Probably revisit the error handling.
-			if _, ok := err.(*rpcError); ok {
+			if _, ok := status.FromError(err); ok {
 				return nil, err
 			}
 			if err == errConnClosing || err == errConnUnavailable {
@@ -208,13 +208,14 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		break
 	}
 	cs := &clientStream{
-		opts:   opts,
-		c:      c,
-		desc:   desc,
-		codec:  cc.dopts.codec,
-		cp:     cc.dopts.cp,
-		dc:     cc.dopts.dc,
-		cancel: cancel,
+		opts:       opts,
+		c:          c,
+		desc:       desc,
+		codec:      cc.dopts.codec,
+		cp:         cc.dopts.cp,
+		dc:         cc.dopts.dc,
+		maxMsgSize: cc.dopts.maxMsgSize,
+		cancel:     cancel,
 
 		put: put,
 		t:   t,
@@ -239,11 +240,7 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 		case <-s.Done():
 			// TODO: The trace of the RPC is terminated here when there is no pending
 			// I/O, which is probably not the optimal solution.
-			if s.StatusCode() == codes.OK {
-				cs.finish(nil)
-			} else {
-				cs.finish(Errorf(s.StatusCode(), "%s", s.StatusDesc()))
-			}
+			cs.finish(s.Status().Err())
 			cs.closeTransportStream(nil)
 		case <-s.GoAway():
 			cs.finish(errConnDrain)
@@ -259,17 +256,18 @@ func newClientStream(ctx context.Context, desc *StreamDesc, cc *ClientConn, meth
 
 // clientStream implements a client side Stream.
 type clientStream struct {
-	opts   []CallOption
-	c      callInfo
-	t      transport.ClientTransport
-	s      *transport.Stream
-	p      *parser
-	desc   *StreamDesc
-	codec  Codec
-	cp     Compressor
-	cbuf   *bytes.Buffer
-	dc     Decompressor
-	cancel context.CancelFunc
+	opts       []CallOption
+	c          callInfo
+	t          transport.ClientTransport
+	s          *transport.Stream
+	p          *parser
+	desc       *StreamDesc
+	codec      Codec
+	cp         Compressor
+	cbuf       *bytes.Buffer
+	dc         Decompressor
+	maxMsgSize int
+	cancel     context.CancelFunc
 
 	tracing bool // set to EnableTracing when the clientStream is created.
 
@@ -382,7 +380,7 @@ func (cs *clientStream) RecvMsg(m interface{}) (err error) {
 			Client: true,
 		}
 	}
-	err = recv(cs.p, cs.codec, cs.s, cs.dc, m, math.MaxInt32, inPayload)
+	err = recv(cs.p, cs.codec, cs.s, cs.dc, m, cs.maxMsgSize, inPayload)
 	defer func() {
 		// err != nil indicates the termination of the stream.
 		if err != nil {
@@ -405,17 +403,17 @@ func (cs *clientStream) RecvMsg(m interface{}) (err error) {
 		}
 		// Special handling for client streaming rpc.
 		// This recv expects EOF or errors, so we don't collect inPayload.
-		err = recv(cs.p, cs.codec, cs.s, cs.dc, m, math.MaxInt32, nil)
+		err = recv(cs.p, cs.codec, cs.s, cs.dc, m, cs.maxMsgSize, nil)
 		cs.closeTransportStream(err)
 		if err == nil {
 			return toRPCErr(errors.New("grpc: client streaming protocol violation: get <nil>, want <EOF>"))
 		}
 		if err == io.EOF {
-			if cs.s.StatusCode() == codes.OK {
-				cs.finish(err)
-				return nil
+			if se := cs.s.Status().Err(); se != nil {
+				return se
 			}
-			return Errorf(cs.s.StatusCode(), "%s", cs.s.StatusDesc())
+			cs.finish(err)
+			return nil
 		}
 		return toRPCErr(err)
 	}
@@ -423,11 +421,11 @@ func (cs *clientStream) RecvMsg(m interface{}) (err error) {
 		cs.closeTransportStream(err)
 	}
 	if err == io.EOF {
-		if cs.s.StatusCode() == codes.OK {
-			// Returns io.EOF to indicate the end of the stream.
-			return
+		if statusErr := cs.s.Status().Err(); statusErr != nil {
+			return statusErr
 		}
-		return Errorf(cs.s.StatusCode(), "%s", cs.s.StatusDesc())
+		// Returns io.EOF to indicate the end of the stream.
+		return
 	}
 	return toRPCErr(err)
 }
@@ -519,8 +517,6 @@ type serverStream struct {
 	dc         Decompressor
 	cbuf       *bytes.Buffer
 	maxMsgSize int
-	statusCode codes.Code
-	statusDesc string
 	trInfo     *traceInfo
 
 	statsHandler stats.Handler
diff --git a/vendor/google.golang.org/grpc/transport/control.go b/vendor/google.golang.org/grpc/transport/control.go
index 2586cba..8d29aee 100644
--- a/vendor/google.golang.org/grpc/transport/control.go
+++ b/vendor/google.golang.org/grpc/transport/control.go
@@ -35,7 +35,9 @@ package transport
 
 import (
 	"fmt"
+	"math"
 	"sync"
+	"time"
 
 	"golang.org/x/net/http2"
 )
@@ -44,8 +46,18 @@ const (
 	// The default value of flow control window size in HTTP2 spec.
 	defaultWindowSize = 65535
 	// The initial window size for flow control.
-	initialWindowSize     = defaultWindowSize      // for an RPC
-	initialConnWindowSize = defaultWindowSize * 16 // for a connection
+	initialWindowSize             = defaultWindowSize      // for an RPC
+	initialConnWindowSize         = defaultWindowSize * 16 // for a connection
+	infinity                      = time.Duration(math.MaxInt64)
+	defaultClientKeepaliveTime    = infinity
+	defaultClientKeepaliveTimeout = time.Duration(20 * time.Second)
+	defaultMaxStreamsClient       = 100
+	defaultMaxConnectionIdle      = infinity
+	defaultMaxConnectionAge       = infinity
+	defaultMaxConnectionAgeGrace  = infinity
+	defaultServerKeepaliveTime    = time.Duration(2 * time.Hour)
+	defaultServerKeepaliveTimeout = time.Duration(20 * time.Second)
+	defaultKeepalivePolicyMinTime = time.Duration(5 * time.Minute)
 )
 
 // The following defines various control items which could flow through
@@ -73,6 +85,8 @@ type resetStream struct {
 func (*resetStream) item() {}
 
 type goAway struct {
+	code      http2.ErrCode
+	debugData []byte
 }
 
 func (*goAway) item() {}
diff --git a/vendor/google.golang.org/grpc/transport/handler_server.go b/vendor/google.golang.org/grpc/transport/handler_server.go
index 10b6dc0..28c9ce0 100644
--- a/vendor/google.golang.org/grpc/transport/handler_server.go
+++ b/vendor/google.golang.org/grpc/transport/handler_server.go
@@ -53,6 +53,7 @@ import (
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/status"
 )
 
 // NewServerHandlerTransport returns a ServerTransport handling gRPC
@@ -182,7 +183,7 @@ func (ht *serverHandlerTransport) do(fn func()) error {
 	}
 }
 
-func (ht *serverHandlerTransport) WriteStatus(s *Stream, statusCode codes.Code, statusDesc string) error {
+func (ht *serverHandlerTransport) WriteStatus(s *Stream, st *status.Status) error {
 	err := ht.do(func() {
 		ht.writeCommonHeaders(s)
 
@@ -192,10 +193,13 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, statusCode codes.Code,
 		ht.rw.(http.Flusher).Flush()
 
 		h := ht.rw.Header()
-		h.Set("Grpc-Status", fmt.Sprintf("%d", statusCode))
-		if statusDesc != "" {
-			h.Set("Grpc-Message", encodeGrpcMessage(statusDesc))
+		h.Set("Grpc-Status", fmt.Sprintf("%d", st.Code()))
+		if m := st.Message(); m != "" {
+			h.Set("Grpc-Message", encodeGrpcMessage(m))
 		}
+
+		// TODO: Support Grpc-Status-Details-Bin
+
 		if md := s.Trailer(); len(md) > 0 {
 			for k, vv := range md {
 				// Clients don't tolerate reading restricted headers after some non restricted ones were sent.
@@ -234,6 +238,7 @@ func (ht *serverHandlerTransport) writeCommonHeaders(s *Stream) {
 	// and https://golang.org/pkg/net/http/#example_ResponseWriter_trailers
 	h.Add("Trailer", "Grpc-Status")
 	h.Add("Trailer", "Grpc-Message")
+	// TODO: Support Grpc-Status-Details-Bin
 
 	if s.sendCompress != "" {
 		h.Set("Grpc-Encoding", s.sendCompress)
@@ -314,7 +319,7 @@ func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), trace
 	if req.TLS != nil {
 		pr.AuthInfo = credentials.TLSInfo{State: *req.TLS}
 	}
-	ctx = metadata.NewContext(ctx, ht.headerMD)
+	ctx = metadata.NewIncomingContext(ctx, ht.headerMD)
 	ctx = peer.NewContext(ctx, pr)
 	s.ctx = newContextWithStream(ctx, s)
 	s.dec = &recvBufferReader{ctx: s.ctx, recv: s.buf}
diff --git a/vendor/google.golang.org/grpc/transport/http2_client.go b/vendor/google.golang.org/grpc/transport/http2_client.go
index 892f8ba..5fc6b75 100644
--- a/vendor/google.golang.org/grpc/transport/http2_client.go
+++ b/vendor/google.golang.org/grpc/transport/http2_client.go
@@ -35,12 +35,12 @@ package transport
 
 import (
 	"bytes"
-	"fmt"
 	"io"
 	"math"
 	"net"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"golang.org/x/net/context"
@@ -49,9 +49,11 @@ import (
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 )
 
 // http2Client implements the ClientTransport interface with HTTP2.
@@ -80,6 +82,8 @@ type http2Client struct {
 	// goAway is closed to notify the upper layer (i.e., addrConn.transportMonitor)
 	// that the server sent GoAway on this transport.
 	goAway chan struct{}
+	// awakenKeepalive is used to wake up keepalive when after it has gone dormant.
+	awakenKeepalive chan struct{}
 
 	framer *framer
 	hBuf   *bytes.Buffer  // the buffer for HPACK encoding
@@ -99,6 +103,11 @@ type http2Client struct {
 
 	creds []credentials.PerRPCCredentials
 
+	// Boolean to keep track of reading activity on transport.
+	// 1 is true and 0 is false.
+	activity uint32 // Accessed atomically.
+	kp       keepalive.ClientParameters
+
 	statsHandler stats.Handler
 
 	mu            sync.Mutex     // guard the following variables
@@ -178,15 +187,19 @@ func newHTTP2Client(ctx context.Context, addr TargetInfo, opts ConnectOptions) (
 			return nil, connectionErrorf(temp, err, "transport: %v", err)
 		}
 	}
-	ua := primaryUA
-	if opts.UserAgent != "" {
-		ua = opts.UserAgent + " " + ua
+	kp := opts.KeepaliveParams
+	// Validate keepalive parameters.
+	if kp.Time == 0 {
+		kp.Time = defaultClientKeepaliveTime
+	}
+	if kp.Timeout == 0 {
+		kp.Timeout = defaultClientKeepaliveTimeout
 	}
 	var buf bytes.Buffer
 	t := &http2Client{
 		ctx:        ctx,
 		target:     addr.Addr,
-		userAgent:  ua,
+		userAgent:  opts.UserAgent,
 		md:         addr.Metadata,
 		conn:       conn,
 		remoteAddr: conn.RemoteAddr(),
@@ -198,6 +211,7 @@ func newHTTP2Client(ctx context.Context, addr TargetInfo, opts ConnectOptions) (
 		shutdownChan:    make(chan struct{}),
 		errorChan:       make(chan struct{}),
 		goAway:          make(chan struct{}),
+		awakenKeepalive: make(chan struct{}, 1),
 		framer:          newFramer(conn),
 		hBuf:            &buf,
 		hEnc:            hpack.NewEncoder(&buf),
@@ -208,10 +222,15 @@ func newHTTP2Client(ctx context.Context, addr TargetInfo, opts ConnectOptions) (
 		state:           reachable,
 		activeStreams:   make(map[uint32]*Stream),
 		creds:           opts.PerRPCCredentials,
-		maxStreams:      math.MaxInt32,
+		maxStreams:      defaultMaxStreamsClient,
+		streamsQuota:    newQuotaPool(defaultMaxStreamsClient),
 		streamSendQuota: defaultWindowSize,
+		kp:              kp,
 		statsHandler:    opts.StatsHandler,
 	}
+	// Make sure awakenKeepalive can't be written upon.
+	// keepalive routine will make it writable, if need be.
+	t.awakenKeepalive <- struct{}{}
 	if t.statsHandler != nil {
 		t.ctx = t.statsHandler.TagConn(t.ctx, &stats.ConnTagInfo{
 			RemoteAddr: t.remoteAddr,
@@ -256,6 +275,9 @@ func newHTTP2Client(ctx context.Context, addr TargetInfo, opts ConnectOptions) (
 		}
 	}
 	go t.controller()
+	if t.kp.Time != infinity {
+		go t.keepalive()
+	}
 	t.writableChan <- 0
 	return t, nil
 }
@@ -289,7 +311,7 @@ func (t *http2Client) newStream(ctx context.Context, callHdr *CallHdr) *Stream {
 	return s
 }
 
-// NewStream creates a stream and register it into the transport as "active"
+// NewStream creates a stream and registers it into the transport as "active"
 // streams.
 func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Stream, err error) {
 	pr := &peer.Peer{
@@ -337,21 +359,18 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 		t.mu.Unlock()
 		return nil, ErrConnClosing
 	}
-	checkStreamsQuota := t.streamsQuota != nil
 	t.mu.Unlock()
-	if checkStreamsQuota {
-		sq, err := wait(ctx, nil, nil, t.shutdownChan, t.streamsQuota.acquire())
-		if err != nil {
-			return nil, err
-		}
-		// Returns the quota balance back.
-		if sq > 1 {
-			t.streamsQuota.add(sq - 1)
-		}
+	sq, err := wait(ctx, nil, nil, t.shutdownChan, t.streamsQuota.acquire())
+	if err != nil {
+		return nil, err
+	}
+	// Returns the quota balance back.
+	if sq > 1 {
+		t.streamsQuota.add(sq - 1)
 	}
 	if _, err := wait(ctx, nil, nil, t.shutdownChan, t.writableChan); err != nil {
 		// Return the quota back now because there is no stream returned to the caller.
-		if _, ok := err.(StreamError); ok && checkStreamsQuota {
+		if _, ok := err.(StreamError); ok {
 			t.streamsQuota.add(1)
 		}
 		return nil, err
@@ -359,9 +378,7 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 	t.mu.Lock()
 	if t.state == draining {
 		t.mu.Unlock()
-		if checkStreamsQuota {
-			t.streamsQuota.add(1)
-		}
+		t.streamsQuota.add(1)
 		// Need to make t writable again so that the rpc in flight can still proceed.
 		t.writableChan <- 0
 		return nil, ErrStreamDrain
@@ -373,17 +390,17 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 	s := t.newStream(ctx, callHdr)
 	s.clientStatsCtx = userCtx
 	t.activeStreams[s.id] = s
-
-	// This stream is not counted when applySetings(...) initialize t.streamsQuota.
-	// Reset t.streamsQuota to the right value.
-	var reset bool
-	if !checkStreamsQuota && t.streamsQuota != nil {
-		reset = true
+	// If the number of active streams change from 0 to 1, then check if keepalive
+	// has gone dormant. If so, wake it up.
+	if len(t.activeStreams) == 1 {
+		select {
+		case t.awakenKeepalive <- struct{}{}:
+			t.framer.writePing(false, false, [8]byte{})
+		default:
+		}
 	}
+
 	t.mu.Unlock()
-	if reset {
-		t.streamsQuota.add(-1)
-	}
 
 	// HPACK encodes various headers. Note that once WriteField(...) is
 	// called, the corresponding headers/continuation frame has to be sent
@@ -415,7 +432,7 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 		hasMD      bool
 		endHeaders bool
 	)
-	if md, ok := metadata.FromContext(ctx); ok {
+	if md, ok := metadata.FromOutgoingContext(ctx); ok {
 		hasMD = true
 		for k, v := range md {
 			// HTTP doesn't allow you to set pseudoheaders after non pseudoheaders were set.
@@ -491,15 +508,11 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 // CloseStream clears the footprint of a stream when the stream is not needed any more.
 // This must not be executed in reader's goroutine.
 func (t *http2Client) CloseStream(s *Stream, err error) {
-	var updateStreams bool
 	t.mu.Lock()
 	if t.activeStreams == nil {
 		t.mu.Unlock()
 		return
 	}
-	if t.streamsQuota != nil {
-		updateStreams = true
-	}
 	delete(t.activeStreams, s.id)
 	if t.state == draining && len(t.activeStreams) == 0 {
 		// The transport is draining and s is the last live stream on t.
@@ -508,10 +521,27 @@ func (t *http2Client) CloseStream(s *Stream, err error) {
 		return
 	}
 	t.mu.Unlock()
-	if updateStreams {
-		t.streamsQuota.add(1)
-	}
+	// rstStream is true in case the stream is being closed at the client-side
+	// and the server needs to be intimated about it by sending a RST_STREAM
+	// frame.
+	// To make sure this frame is written to the wire before the headers of the
+	// next stream waiting for streamsQuota, we add to streamsQuota pool only
+	// after having acquired the writableChan to send RST_STREAM out (look at
+	// the controller() routine).
+	var rstStream bool
+	var rstError http2.ErrCode
+	defer func() {
+		// In case, the client doesn't have to send RST_STREAM to server
+		// we can safely add back to streamsQuota pool now.
+		if !rstStream {
+			t.streamsQuota.add(1)
+			return
+		}
+		t.controlBuf.put(&resetStream{s.id, rstError})
+	}()
 	s.mu.Lock()
+	rstStream = s.rstStream
+	rstError = s.rstError
 	if q := s.fc.resetPendingData(); q > 0 {
 		if n := t.fc.onRead(q); n > 0 {
 			t.controlBuf.put(&windowUpdate{0, n})
@@ -527,8 +557,9 @@ func (t *http2Client) CloseStream(s *Stream, err error) {
 	}
 	s.state = streamDone
 	s.mu.Unlock()
-	if se, ok := err.(StreamError); ok && se.Code != codes.DeadlineExceeded {
-		t.controlBuf.put(&resetStream{s.id, http2.ErrCodeCancel})
+	if _, ok := err.(StreamError); ok {
+		rstStream = true
+		rstError = http2.ErrCodeCancel
 	}
 }
 
@@ -742,7 +773,7 @@ func (t *http2Client) updateWindow(s *Stream, n uint32) {
 }
 
 func (t *http2Client) handleData(f *http2.DataFrame) {
-	size := len(f.Data())
+	size := f.Header().Length
 	if err := t.fc.onData(uint32(size)); err != nil {
 		t.notifyError(connectionErrorf(true, err, "%v", err))
 		return
@@ -756,6 +787,11 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 		return
 	}
 	if size > 0 {
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := t.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{0, w})
+			}
+		}
 		s.mu.Lock()
 		if s.state == streamDone {
 			s.mu.Unlock()
@@ -766,22 +802,27 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 			return
 		}
 		if err := s.fc.onData(uint32(size)); err != nil {
-			s.state = streamDone
-			s.statusCode = codes.Internal
-			s.statusDesc = err.Error()
-			close(s.done)
+			s.rstStream = true
+			s.rstError = http2.ErrCodeFlowControl
+			s.finish(status.New(codes.Internal, err.Error()))
 			s.mu.Unlock()
 			s.write(recvMsg{err: io.EOF})
-			t.controlBuf.put(&resetStream{s.id, http2.ErrCodeFlowControl})
 			return
 		}
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := s.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{s.id, w})
+			}
+		}
 		s.mu.Unlock()
 		// TODO(bradfitz, zhaoq): A copy is required here because there is no
 		// guarantee f.Data() is consumed before the arrival of next frame.
 		// Can this copy be eliminated?
-		data := make([]byte, size)
-		copy(data, f.Data())
-		s.write(recvMsg{data: data})
+		if len(f.Data()) > 0 {
+			data := make([]byte, len(f.Data()))
+			copy(data, f.Data())
+			s.write(recvMsg{data: data})
+		}
 	}
 	// The server has closed the stream without sending trailers.  Record that
 	// the read direction is closed, and set the status appropriately.
@@ -791,10 +832,7 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 			s.mu.Unlock()
 			return
 		}
-		s.state = streamDone
-		s.statusCode = codes.Internal
-		s.statusDesc = "server closed the stream without sending trailers"
-		close(s.done)
+		s.finish(status.New(codes.Internal, "server closed the stream without sending trailers"))
 		s.mu.Unlock()
 		s.write(recvMsg{err: io.EOF})
 	}
@@ -810,18 +848,16 @@ func (t *http2Client) handleRSTStream(f *http2.RSTStreamFrame) {
 		s.mu.Unlock()
 		return
 	}
-	s.state = streamDone
 	if !s.headerDone {
 		close(s.headerChan)
 		s.headerDone = true
 	}
-	s.statusCode, ok = http2ErrConvTab[http2.ErrCode(f.ErrCode)]
+	statusCode, ok := http2ErrConvTab[http2.ErrCode(f.ErrCode)]
 	if !ok {
 		grpclog.Println("transport: http2Client.handleRSTStream found no mapped gRPC status for the received http2 error ", f.ErrCode)
-		s.statusCode = codes.Unknown
+		statusCode = codes.Unknown
 	}
-	s.statusDesc = fmt.Sprintf("stream terminated by RST_STREAM with error code: %d", f.ErrCode)
-	close(s.done)
+	s.finish(status.Newf(statusCode, "stream terminated by RST_STREAM with error code: %d", f.ErrCode))
 	s.mu.Unlock()
 	s.write(recvMsg{err: io.EOF})
 }
@@ -849,6 +885,9 @@ func (t *http2Client) handlePing(f *http2.PingFrame) {
 }
 
 func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
+	if f.ErrCode == http2.ErrCodeEnhanceYourCalm {
+		grpclog.Printf("Client received GoAway with http2.ErrCodeEnhanceYourCalm.")
+	}
 	t.mu.Lock()
 	if t.state == reachable || t.state == draining {
 		if f.LastStreamID > 0 && f.LastStreamID%2 != 1 {
@@ -897,18 +936,17 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 	}
 	var state decodeState
 	for _, hf := range frame.Fields {
-		state.processHeaderField(hf)
-	}
-	if state.err != nil {
-		s.mu.Lock()
-		if !s.headerDone {
-			close(s.headerChan)
-			s.headerDone = true
+		if err := state.processHeaderField(hf); err != nil {
+			s.mu.Lock()
+			if !s.headerDone {
+				close(s.headerChan)
+				s.headerDone = true
+			}
+			s.mu.Unlock()
+			s.write(recvMsg{err: err})
+			// Something wrong. Stops reading even when there is remaining.
+			return
 		}
-		s.mu.Unlock()
-		s.write(recvMsg{err: state.err})
-		// Something wrong. Stops reading even when there is remaining.
-		return
 	}
 
 	endStream := frame.StreamEnded()
@@ -951,10 +989,7 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 	if len(state.mdata) > 0 {
 		s.trailer = state.mdata
 	}
-	s.statusCode = state.statusCode
-	s.statusDesc = state.statusDesc
-	close(s.done)
-	s.state = streamDone
+	s.finish(state.status())
 	s.mu.Unlock()
 	s.write(recvMsg{err: io.EOF})
 }
@@ -982,6 +1017,7 @@ func (t *http2Client) reader() {
 		t.notifyError(err)
 		return
 	}
+	atomic.CompareAndSwapUint32(&t.activity, 0, 1)
 	sf, ok := frame.(*http2.SettingsFrame)
 	if !ok {
 		t.notifyError(err)
@@ -992,6 +1028,7 @@ func (t *http2Client) reader() {
 	// loop to keep reading incoming messages on this transport.
 	for {
 		frame, err := t.framer.readFrame()
+		atomic.CompareAndSwapUint32(&t.activity, 0, 1)
 		if err != nil {
 			// Abort an active stream if the http2.Framer returns a
 			// http2.StreamError. This can happen only if the server's response
@@ -1043,16 +1080,10 @@ func (t *http2Client) applySettings(ss []http2.Setting) {
 				s.Val = math.MaxInt32
 			}
 			t.mu.Lock()
-			reset := t.streamsQuota != nil
-			if !reset {
-				t.streamsQuota = newQuotaPool(int(s.Val) - len(t.activeStreams))
-			}
 			ms := t.maxStreams
 			t.maxStreams = int(s.Val)
 			t.mu.Unlock()
-			if reset {
-				t.streamsQuota.add(int(s.Val) - ms)
-			}
+			t.streamsQuota.add(int(s.Val) - ms)
 		case http2.SettingInitialWindowSize:
 			t.mu.Lock()
 			for _, stream := range t.activeStreams {
@@ -1085,6 +1116,12 @@ func (t *http2Client) controller() {
 						t.framer.writeSettings(true, i.ss...)
 					}
 				case *resetStream:
+					// If the server needs to be to intimated about stream closing,
+					// then we need to make sure the RST_STREAM frame is written to
+					// the wire before the headers of the next stream waiting on
+					// streamQuota. We ensure this by adding to the streamsQuota pool
+					// only after having acquired the writableChan to send RST_STREAM.
+					t.streamsQuota.add(1)
 					t.framer.writeRSTStream(true, i.streamID, i.code)
 				case *flushIO:
 					t.framer.flushWrite()
@@ -1104,6 +1141,61 @@ func (t *http2Client) controller() {
 	}
 }
 
+// keepalive running in a separate goroutune makes sure the connection is alive by sending pings.
+func (t *http2Client) keepalive() {
+	p := &ping{data: [8]byte{}}
+	timer := time.NewTimer(t.kp.Time)
+	for {
+		select {
+		case <-timer.C:
+			if atomic.CompareAndSwapUint32(&t.activity, 1, 0) {
+				timer.Reset(t.kp.Time)
+				continue
+			}
+			// Check if keepalive should go dormant.
+			t.mu.Lock()
+			if len(t.activeStreams) < 1 && !t.kp.PermitWithoutStream {
+				// Make awakenKeepalive writable.
+				<-t.awakenKeepalive
+				t.mu.Unlock()
+				select {
+				case <-t.awakenKeepalive:
+					// If the control gets here a ping has been sent
+					// need to reset the timer with keepalive.Timeout.
+				case <-t.shutdownChan:
+					return
+				}
+			} else {
+				t.mu.Unlock()
+				// Send ping.
+				t.controlBuf.put(p)
+			}
+
+			// By the time control gets here a ping has been sent one way or the other.
+			timer.Reset(t.kp.Timeout)
+			select {
+			case <-timer.C:
+				if atomic.CompareAndSwapUint32(&t.activity, 1, 0) {
+					timer.Reset(t.kp.Time)
+					continue
+				}
+				t.Close()
+				return
+			case <-t.shutdownChan:
+				if !timer.Stop() {
+					<-timer.C
+				}
+				return
+			}
+		case <-t.shutdownChan:
+			if !timer.Stop() {
+				<-timer.C
+			}
+			return
+		}
+	}
+}
+
 func (t *http2Client) Error() <-chan struct{} {
 	return t.errorChan
 }
diff --git a/vendor/google.golang.org/grpc/transport/http2_server.go b/vendor/google.golang.org/grpc/transport/http2_server.go
index a095dd0..31fefc7 100644
--- a/vendor/google.golang.org/grpc/transport/http2_server.go
+++ b/vendor/google.golang.org/grpc/transport/http2_server.go
@@ -38,19 +38,25 @@ import (
 	"errors"
 	"io"
 	"math"
+	"math/rand"
 	"net"
 	"strconv"
 	"sync"
+	"sync/atomic"
+	"time"
 
+	"github.com/golang/protobuf/proto"
 	"golang.org/x/net/context"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/tap"
 )
 
@@ -90,11 +96,33 @@ type http2Server struct {
 
 	stats stats.Handler
 
+	// Flag to keep track of reading activity on transport.
+	// 1 is true and 0 is false.
+	activity uint32 // Accessed atomically.
+	// Keepalive and max-age parameters for the server.
+	kp keepalive.ServerParameters
+
+	// Keepalive enforcement policy.
+	kep keepalive.EnforcementPolicy
+	// The time instance last ping was received.
+	lastPingAt time.Time
+	// Number of times the client has violated keepalive ping policy so far.
+	pingStrikes uint8
+	// Flag to signify that number of ping strikes should be reset to 0.
+	// This is set whenever data or header frames are sent.
+	// 1 means yes.
+	resetPingStrikes uint32 // Accessed atomically.
+
 	mu            sync.Mutex // guard the following
 	state         transportState
 	activeStreams map[uint32]*Stream
 	// the per-stream outbound flow control window size set by the peer.
 	streamSendQuota uint32
+	// idle is the time instant when the connection went idle.
+	// This is either the begining of the connection or when the number of
+	// RPCs go down to 0.
+	// When the connection is busy, this value is set to 0.
+	idle time.Time
 }
 
 // newHTTP2Server constructs a ServerTransport based on HTTP2. ConnectionError is
@@ -128,6 +156,28 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 			return nil, connectionErrorf(true, err, "transport: %v", err)
 		}
 	}
+	kp := config.KeepaliveParams
+	if kp.MaxConnectionIdle == 0 {
+		kp.MaxConnectionIdle = defaultMaxConnectionIdle
+	}
+	if kp.MaxConnectionAge == 0 {
+		kp.MaxConnectionAge = defaultMaxConnectionAge
+	}
+	// Add a jitter to MaxConnectionAge.
+	kp.MaxConnectionAge += getJitter(kp.MaxConnectionAge)
+	if kp.MaxConnectionAgeGrace == 0 {
+		kp.MaxConnectionAgeGrace = defaultMaxConnectionAgeGrace
+	}
+	if kp.Time == 0 {
+		kp.Time = defaultServerKeepaliveTime
+	}
+	if kp.Timeout == 0 {
+		kp.Timeout = defaultServerKeepaliveTimeout
+	}
+	kep := config.KeepalivePolicy
+	if kep.MinTime == 0 {
+		kep.MinTime = defaultKeepalivePolicyMinTime
+	}
 	var buf bytes.Buffer
 	t := &http2Server{
 		ctx:             context.Background(),
@@ -149,6 +199,9 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 		activeStreams:   make(map[uint32]*Stream),
 		streamSendQuota: defaultWindowSize,
 		stats:           config.StatsHandler,
+		kp:              kp,
+		idle:            time.Now(),
+		kep:             kep,
 	}
 	if t.stats != nil {
 		t.ctx = t.stats.TagConn(t.ctx, &stats.ConnTagInfo{
@@ -159,6 +212,7 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 		t.stats.HandleConn(t.ctx, connBegin)
 	}
 	go t.controller()
+	go t.keepalive()
 	t.writableChan <- 0
 	return t, nil
 }
@@ -175,13 +229,12 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 
 	var state decodeState
 	for _, hf := range frame.Fields {
-		state.processHeaderField(hf)
-	}
-	if err := state.err; err != nil {
-		if se, ok := err.(StreamError); ok {
-			t.controlBuf.put(&resetStream{s.id, statusCodeConvTab[se.Code]})
+		if err := state.processHeaderField(hf); err != nil {
+			if se, ok := err.(StreamError); ok {
+				t.controlBuf.put(&resetStream{s.id, statusCodeConvTab[se.Code]})
+			}
+			return
 		}
-		return
 	}
 
 	if frame.StreamEnded() {
@@ -208,7 +261,7 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	s.ctx = newContextWithStream(s.ctx, s)
 	// Attach the received metadata to the context.
 	if len(state.mdata) > 0 {
-		s.ctx = metadata.NewContext(s.ctx, state.mdata)
+		s.ctx = metadata.NewIncomingContext(s.ctx, state.mdata)
 	}
 
 	s.dec = &recvBufferReader{
@@ -248,6 +301,9 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	t.maxStreamID = s.id
 	s.sendQuotaPool = newQuotaPool(int(t.streamSendQuota))
 	t.activeStreams[s.id] = s
+	if len(t.activeStreams) == 1 {
+		t.idle = time.Time{}
+	}
 	t.mu.Unlock()
 	s.windowHandler = func(n int) {
 		t.updateWindow(s, uint32(n))
@@ -295,6 +351,7 @@ func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.
 		t.Close()
 		return
 	}
+	atomic.StoreUint32(&t.activity, 1)
 	sf, ok := frame.(*http2.SettingsFrame)
 	if !ok {
 		grpclog.Printf("transport: http2Server.HandleStreams saw invalid preface type %T from client", frame)
@@ -305,6 +362,7 @@ func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.
 
 	for {
 		frame, err := t.framer.readFrame()
+		atomic.StoreUint32(&t.activity, 1)
 		if err != nil {
 			if se, ok := err.(http2.StreamError); ok {
 				t.mu.Lock()
@@ -381,7 +439,7 @@ func (t *http2Server) updateWindow(s *Stream, n uint32) {
 }
 
 func (t *http2Server) handleData(f *http2.DataFrame) {
-	size := len(f.Data())
+	size := f.Header().Length
 	if err := t.fc.onData(uint32(size)); err != nil {
 		grpclog.Printf("transport: http2Server %v", err)
 		t.Close()
@@ -396,6 +454,11 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 		return
 	}
 	if size > 0 {
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := t.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{0, w})
+			}
+		}
 		s.mu.Lock()
 		if s.state == streamDone {
 			s.mu.Unlock()
@@ -411,13 +474,20 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 			t.controlBuf.put(&resetStream{s.id, http2.ErrCodeFlowControl})
 			return
 		}
+		if f.Header().Flags.Has(http2.FlagDataPadded) {
+			if w := s.fc.onRead(uint32(size) - uint32(len(f.Data()))); w > 0 {
+				t.controlBuf.put(&windowUpdate{s.id, w})
+			}
+		}
 		s.mu.Unlock()
 		// TODO(bradfitz, zhaoq): A copy is required here because there is no
 		// guarantee f.Data() is consumed before the arrival of next frame.
 		// Can this copy be eliminated?
-		data := make([]byte, size)
-		copy(data, f.Data())
-		s.write(recvMsg{data: data})
+		if len(f.Data()) > 0 {
+			data := make([]byte, len(f.Data()))
+			copy(data, f.Data())
+			s.write(recvMsg{data: data})
+		}
 	}
 	if f.Header().Flags.Has(http2.FlagDataEndStream) {
 		// Received the end of stream from the client.
@@ -451,6 +521,11 @@ func (t *http2Server) handleSettings(f *http2.SettingsFrame) {
 	t.controlBuf.put(&settings{ack: true, ss: ss})
 }
 
+const (
+	maxPingStrikes     = 2
+	defaultPingTimeout = 2 * time.Hour
+)
+
 func (t *http2Server) handlePing(f *http2.PingFrame) {
 	if f.IsAck() { // Do nothing.
 		return
@@ -458,6 +533,38 @@ func (t *http2Server) handlePing(f *http2.PingFrame) {
 	pingAck := &ping{ack: true}
 	copy(pingAck.data[:], f.Data[:])
 	t.controlBuf.put(pingAck)
+
+	now := time.Now()
+	defer func() {
+		t.lastPingAt = now
+	}()
+	// A reset ping strikes means that we don't need to check for policy
+	// violation for this ping and the pingStrikes counter should be set
+	// to 0.
+	if atomic.CompareAndSwapUint32(&t.resetPingStrikes, 1, 0) {
+		t.pingStrikes = 0
+		return
+	}
+	t.mu.Lock()
+	ns := len(t.activeStreams)
+	t.mu.Unlock()
+	if ns < 1 && !t.kep.PermitWithoutStream {
+		// Keepalive shouldn't be active thus, this new ping should
+		// have come after atleast defaultPingTimeout.
+		if t.lastPingAt.Add(defaultPingTimeout).After(now) {
+			t.pingStrikes++
+		}
+	} else {
+		// Check if keepalive policy is respected.
+		if t.lastPingAt.Add(t.kep.MinTime).After(now) {
+			t.pingStrikes++
+		}
+	}
+
+	if t.pingStrikes > maxPingStrikes {
+		// Send goaway and close the connection.
+		t.controlBuf.put(&goAway{code: http2.ErrCodeEnhanceYourCalm, debugData: []byte("too_many_pings")})
+	}
 }
 
 func (t *http2Server) handleWindowUpdate(f *http2.WindowUpdateFrame) {
@@ -476,6 +583,13 @@ func (t *http2Server) writeHeaders(s *Stream, b *bytes.Buffer, endStream bool) e
 	first := true
 	endHeaders := false
 	var err error
+	defer func() {
+		if err == nil {
+			// Reset ping strikes when seding headers since that might cause the
+			// peer to send ping.
+			atomic.StoreUint32(&t.resetPingStrikes, 1)
+		}
+	}()
 	// Sends the headers in a single batch.
 	for !endHeaders {
 		size := t.hBuf.Len()
@@ -557,7 +671,7 @@ func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error {
 // There is no further I/O operations being able to perform on this stream.
 // TODO(zhaoq): Now it indicates the end of entire stream. Revisit if early
 // OK is adopted.
-func (t *http2Server) WriteStatus(s *Stream, statusCode codes.Code, statusDesc string) error {
+func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 	var headersSent, hasHeader bool
 	s.mu.Lock()
 	if s.state == streamDone {
@@ -588,9 +702,24 @@ func (t *http2Server) WriteStatus(s *Stream, statusCode codes.Code, statusDesc s
 	t.hEnc.WriteField(
 		hpack.HeaderField{
 			Name:  "grpc-status",
-			Value: strconv.Itoa(int(statusCode)),
+			Value: strconv.Itoa(int(st.Code())),
 		})
-	t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-message", Value: encodeGrpcMessage(statusDesc)})
+	t.hEnc.WriteField(hpack.HeaderField{Name: "grpc-message", Value: encodeGrpcMessage(st.Message())})
+
+	if p := st.Proto(); p != nil && len(p.Details) > 0 {
+		stBytes, err := proto.Marshal(p)
+		if err != nil {
+			// TODO: return error instead, when callers are able to handle it.
+			panic(err)
+		}
+
+		for k, v := range metadata.New(map[string]string{"grpc-status-details-bin": (string)(stBytes)}) {
+			for _, entry := range v {
+				t.hEnc.WriteField(hpack.HeaderField{Name: k, Value: entry})
+			}
+		}
+	}
+
 	// Attach the trailer metadata.
 	for k, v := range s.trailer {
 		// Clients don't tolerate reading restricted headers after some non restricted ones were sent.
@@ -619,7 +748,7 @@ func (t *http2Server) WriteStatus(s *Stream, statusCode codes.Code, statusDesc s
 
 // Write converts the data into HTTP2 data frame and sends it out. Non-nil error
 // is returns if it fails (e.g., framing error, transport error).
-func (t *http2Server) Write(s *Stream, data []byte, opts *Options) error {
+func (t *http2Server) Write(s *Stream, data []byte, opts *Options) (err error) {
 	// TODO(zhaoq): Support multi-writers for a single stream.
 	var writeHeaderFrame bool
 	s.mu.Lock()
@@ -634,6 +763,13 @@ func (t *http2Server) Write(s *Stream, data []byte, opts *Options) error {
 	if writeHeaderFrame {
 		t.WriteHeader(s, nil)
 	}
+	defer func() {
+		if err == nil {
+			// Reset ping strikes when sending data since this might cause
+			// the peer to send ping.
+			atomic.StoreUint32(&t.resetPingStrikes, 1)
+		}
+	}()
 	r := bytes.NewBuffer(data)
 	for {
 		if r.Len() == 0 {
@@ -723,6 +859,91 @@ func (t *http2Server) applySettings(ss []http2.Setting) {
 	}
 }
 
+// keepalive running in a separate goroutine does the following:
+// 1. Gracefully closes an idle connection after a duration of keepalive.MaxConnectionIdle.
+// 2. Gracefully closes any connection after a duration of keepalive.MaxConnectionAge.
+// 3. Forcibly closes a connection after an additive period of keepalive.MaxConnectionAgeGrace over keepalive.MaxConnectionAge.
+// 4. Makes sure a connection is alive by sending pings with a frequency of keepalive.Time and closes a non-resposive connection
+// after an additional duration of keepalive.Timeout.
+func (t *http2Server) keepalive() {
+	p := &ping{}
+	var pingSent bool
+	maxIdle := time.NewTimer(t.kp.MaxConnectionIdle)
+	maxAge := time.NewTimer(t.kp.MaxConnectionAge)
+	keepalive := time.NewTimer(t.kp.Time)
+	// NOTE: All exit paths of this function should reset their
+	// respecitve timers. A failure to do so will cause the
+	// following clean-up to deadlock and eventually leak.
+	defer func() {
+		if !maxIdle.Stop() {
+			<-maxIdle.C
+		}
+		if !maxAge.Stop() {
+			<-maxAge.C
+		}
+		if !keepalive.Stop() {
+			<-keepalive.C
+		}
+	}()
+	for {
+		select {
+		case <-maxIdle.C:
+			t.mu.Lock()
+			idle := t.idle
+			if idle.IsZero() { // The connection is non-idle.
+				t.mu.Unlock()
+				maxIdle.Reset(t.kp.MaxConnectionIdle)
+				continue
+			}
+			val := t.kp.MaxConnectionIdle - time.Since(idle)
+			if val <= 0 {
+				// The connection has been idle for a duration of keepalive.MaxConnectionIdle or more.
+				// Gracefully close the connection.
+				t.state = draining
+				t.mu.Unlock()
+				t.Drain()
+				// Reseting the timer so that the clean-up doesn't deadlock.
+				maxIdle.Reset(infinity)
+				return
+			}
+			t.mu.Unlock()
+			maxIdle.Reset(val)
+		case <-maxAge.C:
+			t.mu.Lock()
+			t.state = draining
+			t.mu.Unlock()
+			t.Drain()
+			maxAge.Reset(t.kp.MaxConnectionAgeGrace)
+			select {
+			case <-maxAge.C:
+				// Close the connection after grace period.
+				t.Close()
+				// Reseting the timer so that the clean-up doesn't deadlock.
+				maxAge.Reset(infinity)
+			case <-t.shutdownChan:
+			}
+			return
+		case <-keepalive.C:
+			if atomic.CompareAndSwapUint32(&t.activity, 1, 0) {
+				pingSent = false
+				keepalive.Reset(t.kp.Time)
+				continue
+			}
+			if pingSent {
+				t.Close()
+				// Reseting the timer so that the clean-up doesn't deadlock.
+				keepalive.Reset(infinity)
+				return
+			}
+			pingSent = true
+			t.controlBuf.put(p)
+			keepalive.Reset(t.kp.Timeout)
+		case <-t.shutdownChan:
+			return
+		}
+	}
+}
+
 // controller running in a separate goroutine takes charge of sending control
 // frames (e.g., window update, reset stream, setting, etc.) to the server.
 func (t *http2Server) controller() {
@@ -754,7 +975,10 @@ func (t *http2Server) controller() {
 					sid := t.maxStreamID
 					t.state = draining
 					t.mu.Unlock()
-					t.framer.writeGoAway(true, sid, http2.ErrCodeNo, nil)
+					t.framer.writeGoAway(true, sid, i.code, i.debugData)
+					if i.code == http2.ErrCodeEnhanceYourCalm {
+						t.Close()
+					}
 				case *flushIO:
 					t.framer.flushWrite()
 				case *ping:
@@ -804,6 +1028,9 @@ func (t *http2Server) Close() (err error) {
 func (t *http2Server) closeStream(s *Stream) {
 	t.mu.Lock()
 	delete(t.activeStreams, s.id)
+	if len(t.activeStreams) == 0 {
+		t.idle = time.Now()
+	}
 	if t.state == draining && len(t.activeStreams) == 0 {
 		defer t.Close()
 	}
@@ -831,5 +1058,17 @@ func (t *http2Server) RemoteAddr() net.Addr {
 }
 
 func (t *http2Server) Drain() {
-	t.controlBuf.put(&goAway{})
+	t.controlBuf.put(&goAway{code: http2.ErrCodeNo})
+}
+
+var rgen = rand.New(rand.NewSource(time.Now().UnixNano()))
+
+func getJitter(v time.Duration) time.Duration {
+	if v == infinity {
+		return 0
+	}
+	// Generate a jitter between +/- 10% of the value.
+	r := int64(v / 10)
+	j := rgen.Int63n(2*r) - r
+	return time.Duration(j)
 }
diff --git a/vendor/google.golang.org/grpc/transport/http_util.go b/vendor/google.golang.org/grpc/transport/http_util.go
index a3c68d4..6adef77 100644
--- a/vendor/google.golang.org/grpc/transport/http_util.go
+++ b/vendor/google.golang.org/grpc/transport/http_util.go
@@ -44,16 +44,17 @@ import (
 	"sync/atomic"
 	"time"
 
+	"github.com/golang/protobuf/proto"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
+	spb "google.golang.org/genproto/googleapis/rpc/status"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/status"
 )
 
 const (
-	// The primary user agent
-	primaryUA = "grpc-go/1.0"
 	// http2MaxFrameLen specifies the max length of a HTTP2 frame.
 	http2MaxFrameLen = 16384 // 16KB frame
 	// http://http2.github.io/http2-spec/#SettingValues
@@ -92,13 +93,15 @@ var (
 // Records the states during HPACK decoding. Must be reset once the
 // decoding of the entire headers are finished.
 type decodeState struct {
-	err error // first error encountered decoding
-
 	encoding string
-	// statusCode caches the stream status received from the trailer
-	// the server sent. Client side only.
-	statusCode codes.Code
-	statusDesc string
+	// statusGen caches the stream status received from the trailer the server
+	// sent.  Client side only.  Do not access directly.  After all trailers are
+	// parsed, use the status method to retrieve the status.
+	statusGen *status.Status
+	// rawStatusCode and rawStatusMsg are set from the raw trailer fields and are not
+	// intended for direct access outside of parsing.
+	rawStatusCode int32
+	rawStatusMsg  string
 	// Server side only fields.
 	timeoutSet bool
 	timeout    time.Duration
@@ -121,6 +124,7 @@ func isReservedHeader(hdr string) bool {
 		"grpc-message",
 		"grpc-status",
 		"grpc-timeout",
+		"grpc-status-details-bin",
 		"te":
 		return true
 	default:
@@ -139,12 +143,6 @@ func isWhitelistedPseudoHeader(hdr string) bool {
 	}
 }
 
-func (d *decodeState) setErr(err error) {
-	if d.err == nil {
-		d.err = err
-	}
-}
-
 func validContentType(t string) bool {
 	e := "application/grpc"
 	if !strings.HasPrefix(t, e) {
@@ -158,56 +156,62 @@ func validContentType(t string) bool {
 	return true
 }
 
-func (d *decodeState) processHeaderField(f hpack.HeaderField) {
+func (d *decodeState) status() *status.Status {
+	if d.statusGen == nil {
+		// No status-details were provided; generate status using code/msg.
+		d.statusGen = status.New(codes.Code(d.rawStatusCode), d.rawStatusMsg)
+	}
+	return d.statusGen
+}
+
+func (d *decodeState) processHeaderField(f hpack.HeaderField) error {
 	switch f.Name {
 	case "content-type":
 		if !validContentType(f.Value) {
-			d.setErr(streamErrorf(codes.FailedPrecondition, "transport: received the unexpected content-type %q", f.Value))
-			return
+			return streamErrorf(codes.FailedPrecondition, "transport: received the unexpected content-type %q", f.Value)
 		}
 	case "grpc-encoding":
 		d.encoding = f.Value
 	case "grpc-status":
 		code, err := strconv.Atoi(f.Value)
 		if err != nil {
-			d.setErr(streamErrorf(codes.Internal, "transport: malformed grpc-status: %v", err))
-			return
+			return streamErrorf(codes.Internal, "transport: malformed grpc-status: %v", err)
 		}
-		d.statusCode = codes.Code(code)
+		d.rawStatusCode = int32(code)
 	case "grpc-message":
-		d.statusDesc = decodeGrpcMessage(f.Value)
+		d.rawStatusMsg = decodeGrpcMessage(f.Value)
+	case "grpc-status-details-bin":
+		_, v, err := metadata.DecodeKeyValue("grpc-status-details-bin", f.Value)
+		if err != nil {
+			return streamErrorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+		}
+		s := &spb.Status{}
+		if err := proto.Unmarshal([]byte(v), s); err != nil {
+			return streamErrorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
+		}
+		d.statusGen = status.FromProto(s)
 	case "grpc-timeout":
 		d.timeoutSet = true
 		var err error
-		d.timeout, err = decodeTimeout(f.Value)
-		if err != nil {
-			d.setErr(streamErrorf(codes.Internal, "transport: malformed time-out: %v", err))
-			return
+		if d.timeout, err = decodeTimeout(f.Value); err != nil {
+			return streamErrorf(codes.Internal, "transport: malformed time-out: %v", err)
 		}
 	case ":path":
 		d.method = f.Value
 	default:
 		if !isReservedHeader(f.Name) || isWhitelistedPseudoHeader(f.Name) {
-			if f.Name == "user-agent" {
-				i := strings.LastIndex(f.Value, " ")
-				if i == -1 {
-					// There is no application user agent string being set.
-					return
-				}
-				// Extract the application user agent string.
-				f.Value = f.Value[:i]
-			}
 			if d.mdata == nil {
 				d.mdata = make(map[string][]string)
 			}
 			k, v, err := metadata.DecodeKeyValue(f.Name, f.Value)
 			if err != nil {
 				grpclog.Printf("Failed to decode (%q, %q): %v", f.Name, f.Value, err)
-				return
+				return nil
 			}
 			d.mdata[k] = append(d.mdata[k], v)
 		}
 	}
+	return nil
 }
 
 type timeoutUnit uint8
diff --git a/vendor/google.golang.org/grpc/transport/transport.go b/vendor/google.golang.org/grpc/transport/transport.go
index caee54a..b62f702 100644
--- a/vendor/google.golang.org/grpc/transport/transport.go
+++ b/vendor/google.golang.org/grpc/transport/transport.go
@@ -45,10 +45,13 @@ import (
 	"sync"
 
 	"golang.org/x/net/context"
+	"golang.org/x/net/http2"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/stats"
+	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/tap"
 )
 
@@ -210,9 +213,13 @@ type Stream struct {
 	// true iff headerChan is closed. Used to avoid closing headerChan
 	// multiple times.
 	headerDone bool
-	// the status received from the server.
-	statusCode codes.Code
-	statusDesc string
+	// the status error received from the server.
+	status *status.Status
+	// rstStream indicates whether a RST_STREAM frame needs to be sent
+	// to the server to signify that this stream is closing.
+	rstStream bool
+	// rstError is the error that needs to be sent along with the RST_STREAM frame.
+	rstError http2.ErrCode
 }
 
 // RecvCompress returns the compression algorithm applied to the inbound
@@ -277,14 +284,9 @@ func (s *Stream) Method() string {
 	return s.method
 }
 
-// StatusCode returns statusCode received from the server.
-func (s *Stream) StatusCode() codes.Code {
-	return s.statusCode
-}
-
-// StatusDesc returns statusDesc received from the server.
-func (s *Stream) StatusDesc() string {
-	return s.statusDesc
+// Status returns the status received from the server.
+func (s *Stream) Status() *status.Status {
+	return s.status
 }
 
 // SetHeader sets the header metadata. This can be called multiple times.
@@ -331,6 +333,20 @@ func (s *Stream) Read(p []byte) (n int, err error) {
 	return
 }
 
+// finish sets the stream's state and status, and closes the done channel.
+// s.mu must be held by the caller.  st must always be non-nil.
+func (s *Stream) finish(st *status.Status) {
+	s.status = st
+	s.state = streamDone
+	close(s.done)
+}
+
+// GoString is implemented by Stream so context.String() won't
+// race when printing %#v.
+func (s *Stream) GoString() string {
+	return fmt.Sprintf("<stream: %p, %v>", s, s.method)
+}
+
 // The key to save transport.Stream in the context.
 type streamKey struct{}
 
@@ -358,10 +374,12 @@ const (
 
 // ServerConfig consists of all the configurations to establish a server transport.
 type ServerConfig struct {
-	MaxStreams   uint32
-	AuthInfo     credentials.AuthInfo
-	InTapHandle  tap.ServerInHandle
-	StatsHandler stats.Handler
+	MaxStreams      uint32
+	AuthInfo        credentials.AuthInfo
+	InTapHandle     tap.ServerInHandle
+	StatsHandler    stats.Handler
+	KeepaliveParams keepalive.ServerParameters
+	KeepalivePolicy keepalive.EnforcementPolicy
 }
 
 // NewServerTransport creates a ServerTransport with conn or non-nil error
@@ -385,6 +403,8 @@ type ConnectOptions struct {
 	PerRPCCredentials []credentials.PerRPCCredentials
 	// TransportCredentials stores the Authenticator required to setup a client connection.
 	TransportCredentials credentials.TransportCredentials
+	// KeepaliveParams stores the keepalive parameters.
+	KeepaliveParams keepalive.ClientParameters
 	// StatsHandler stores the handler for stats.
 	StatsHandler stats.Handler
 }
@@ -492,10 +512,9 @@ type ServerTransport interface {
 	// Write may not be called on all streams.
 	Write(s *Stream, data []byte, opts *Options) error
 
-	// WriteStatus sends the status of a stream to the client.
-	// WriteStatus is the final call made on a stream and always
-	// occurs.
-	WriteStatus(s *Stream, statusCode codes.Code, statusDesc string) error
+	// WriteStatus sends the status of a stream to the client.  WriteStatus is
+	// the final call made on a stream and always occurs.
+	WriteStatus(s *Stream, st *status.Status) error
 
 	// Close tears down the transport. Once it is called, the transport
 	// should not be accessed any more. All the pending streams and their
@@ -561,6 +580,8 @@ var (
 	ErrStreamDrain = streamErrorf(codes.Unavailable, "the server stops accepting new RPCs")
 )
 
+// TODO: See if we can replace StreamError with status package errors.
+
 // StreamError is an error that only affects one stream within a connection.
 type StreamError struct {
 	Code codes.Code
@@ -568,7 +589,7 @@ type StreamError struct {
 }
 
 func (e StreamError) Error() string {
-	return fmt.Sprintf("stream error: code = %d desc = %q", e.Code, e.Desc)
+	return fmt.Sprintf("stream error: code = %s desc = %q", e.Code, e.Desc)
 }
 
 // ContextErr converts the error from context package into a StreamError.