updated GHA

Update to v2 SDK
updated dependencies

vendor/google.golang.org/grpc/internal/balancer/gracefulswitch/gracefulswitch.go

@@ -0,0 +1,384 @@
+/*
+ *
+ * Copyright 2022 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package gracefulswitch implements a graceful switch load balancer.
+package gracefulswitch
+
+import (
+	"errors"
+	"fmt"
+	"sync"
+
+	"google.golang.org/grpc/balancer"
+	"google.golang.org/grpc/balancer/base"
+	"google.golang.org/grpc/connectivity"
+	"google.golang.org/grpc/resolver"
+)
+
+var errBalancerClosed = errors.New("gracefulSwitchBalancer is closed")
+var _ balancer.Balancer = (*Balancer)(nil)
+
+// NewBalancer returns a graceful switch Balancer.
+func NewBalancer(cc balancer.ClientConn, opts balancer.BuildOptions) *Balancer {
+	return &Balancer{
+		cc:    cc,
+		bOpts: opts,
+	}
+}
+
+// Balancer is a utility to gracefully switch from one balancer to
+// a new balancer. It implements the balancer.Balancer interface.
+type Balancer struct {
+	bOpts balancer.BuildOptions
+	cc    balancer.ClientConn
+
+	// mu protects the following fields and all fields within balancerCurrent
+	// and balancerPending. mu does not need to be held when calling into the
+	// child balancers, as all calls into these children happen only as a direct
+	// result of a call into the gracefulSwitchBalancer, which are also
+	// guaranteed to be synchronous. There is one exception: an UpdateState call
+	// from a child balancer when current and pending are populated can lead to
+	// calling Close() on the current. To prevent that racing with an
+	// UpdateSubConnState from the channel, we hold currentMu during Close and
+	// UpdateSubConnState calls.
+	mu              sync.Mutex
+	balancerCurrent *balancerWrapper
+	balancerPending *balancerWrapper
+	closed          bool // set to true when this balancer is closed
+
+	// currentMu must be locked before mu. This mutex guards against this
+	// sequence of events: UpdateSubConnState() called, finds the
+	// balancerCurrent, gives up lock, updateState comes in, causes Close() on
+	// balancerCurrent before the UpdateSubConnState is called on the
+	// balancerCurrent.
+	currentMu sync.Mutex
+}
+
+// swap swaps out the current lb with the pending lb and updates the ClientConn.
+// The caller must hold gsb.mu.
+func (gsb *Balancer) swap() {
+	gsb.cc.UpdateState(gsb.balancerPending.lastState)
+	cur := gsb.balancerCurrent
+	gsb.balancerCurrent = gsb.balancerPending
+	gsb.balancerPending = nil
+	go func() {
+		gsb.currentMu.Lock()
+		defer gsb.currentMu.Unlock()
+		cur.Close()
+	}()
+}
+
+// Helper function that checks if the balancer passed in is current or pending.
+// The caller must hold gsb.mu.
+func (gsb *Balancer) balancerCurrentOrPending(bw *balancerWrapper) bool {
+	return bw == gsb.balancerCurrent || bw == gsb.balancerPending
+}
+
+// SwitchTo initializes the graceful switch process, which completes based on
+// connectivity state changes on the current/pending balancer. Thus, the switch
+// process is not complete when this method returns. This method must be called
+// synchronously alongside the rest of the balancer.Balancer methods this
+// Graceful Switch Balancer implements.
+func (gsb *Balancer) SwitchTo(builder balancer.Builder) error {
+	gsb.mu.Lock()
+	if gsb.closed {
+		gsb.mu.Unlock()
+		return errBalancerClosed
+	}
+	bw := &balancerWrapper{
+		gsb: gsb,
+		lastState: balancer.State{
+			ConnectivityState: connectivity.Connecting,
+			Picker:            base.NewErrPicker(balancer.ErrNoSubConnAvailable),
+		},
+		subconns: make(map[balancer.SubConn]bool),
+	}
+	balToClose := gsb.balancerPending // nil if there is no pending balancer
+	if gsb.balancerCurrent == nil {
+		gsb.balancerCurrent = bw
+	} else {
+		gsb.balancerPending = bw
+	}
+	gsb.mu.Unlock()
+	balToClose.Close()
+	// This function takes a builder instead of a balancer because builder.Build
+	// can call back inline, and this utility needs to handle the callbacks.
+	newBalancer := builder.Build(bw, gsb.bOpts)
+	if newBalancer == nil {
+		// This is illegal and should never happen; we clear the balancerWrapper
+		// we were constructing if it happens to avoid a potential panic.
+		gsb.mu.Lock()
+		if gsb.balancerPending != nil {
+			gsb.balancerPending = nil
+		} else {
+			gsb.balancerCurrent = nil
+		}
+		gsb.mu.Unlock()
+		return balancer.ErrBadResolverState
+	}
+
+	// This write doesn't need to take gsb.mu because this field never gets read
+	// or written to on any calls from the current or pending. Calls from grpc
+	// to this balancer are guaranteed to be called synchronously, so this
+	// bw.Balancer field will never be forwarded to until this SwitchTo()
+	// function returns.
+	bw.Balancer = newBalancer
+	return nil
+}
+
+// Returns nil if the graceful switch balancer is closed.
+func (gsb *Balancer) latestBalancer() *balancerWrapper {
+	gsb.mu.Lock()
+	defer gsb.mu.Unlock()
+	if gsb.balancerPending != nil {
+		return gsb.balancerPending
+	}
+	return gsb.balancerCurrent
+}
+
+// UpdateClientConnState forwards the update to the latest balancer created.
+func (gsb *Balancer) UpdateClientConnState(state balancer.ClientConnState) error {
+	// The resolver data is only relevant to the most recent LB Policy.
+	balToUpdate := gsb.latestBalancer()
+	if balToUpdate == nil {
+		return errBalancerClosed
+	}
+	// Perform this call without gsb.mu to prevent deadlocks if the child calls
+	// back into the channel. The latest balancer can never be closed during a
+	// call from the channel, even without gsb.mu held.
+	return balToUpdate.UpdateClientConnState(state)
+}
+
+// ResolverError forwards the error to the latest balancer created.
+func (gsb *Balancer) ResolverError(err error) {
+	// The resolver data is only relevant to the most recent LB Policy.
+	balToUpdate := gsb.latestBalancer()
+	if balToUpdate == nil {
+		return
+	}
+	// Perform this call without gsb.mu to prevent deadlocks if the child calls
+	// back into the channel. The latest balancer can never be closed during a
+	// call from the channel, even without gsb.mu held.
+	balToUpdate.ResolverError(err)
+}
+
+// ExitIdle forwards the call to the latest balancer created.
+//
+// If the latest balancer does not support ExitIdle, the subConns are
+// re-connected to manually.
+func (gsb *Balancer) ExitIdle() {
+	balToUpdate := gsb.latestBalancer()
+	if balToUpdate == nil {
+		return
+	}
+	// There is no need to protect this read with a mutex, as the write to the
+	// Balancer field happens in SwitchTo, which completes before this can be
+	// called.
+	if ei, ok := balToUpdate.Balancer.(balancer.ExitIdler); ok {
+		ei.ExitIdle()
+		return
+	}
+	gsb.mu.Lock()
+	defer gsb.mu.Unlock()
+	for sc := range balToUpdate.subconns {
+		sc.Connect()
+	}
+}
+
+// UpdateSubConnState forwards the update to the appropriate child.
+func (gsb *Balancer) UpdateSubConnState(sc balancer.SubConn, state balancer.SubConnState) {
+	gsb.currentMu.Lock()
+	defer gsb.currentMu.Unlock()
+	gsb.mu.Lock()
+	// Forward update to the appropriate child.  Even if there is a pending
+	// balancer, the current balancer should continue to get SubConn updates to
+	// maintain the proper state while the pending is still connecting.
+	var balToUpdate *balancerWrapper
+	if gsb.balancerCurrent != nil && gsb.balancerCurrent.subconns[sc] {
+		balToUpdate = gsb.balancerCurrent
+	} else if gsb.balancerPending != nil && gsb.balancerPending.subconns[sc] {
+		balToUpdate = gsb.balancerPending
+	}
+	gsb.mu.Unlock()
+	if balToUpdate == nil {
+		// SubConn belonged to a stale lb policy that has not yet fully closed,
+		// or the balancer was already closed.
+		return
+	}
+	balToUpdate.UpdateSubConnState(sc, state)
+}
+
+// Close closes any active child balancers.
+func (gsb *Balancer) Close() {
+	gsb.mu.Lock()
+	gsb.closed = true
+	currentBalancerToClose := gsb.balancerCurrent
+	gsb.balancerCurrent = nil
+	pendingBalancerToClose := gsb.balancerPending
+	gsb.balancerPending = nil
+	gsb.mu.Unlock()
+
+	currentBalancerToClose.Close()
+	pendingBalancerToClose.Close()
+}
+
+// balancerWrapper wraps a balancer.Balancer, and overrides some Balancer
+// methods to help cleanup SubConns created by the wrapped balancer.
+//
+// It implements the balancer.ClientConn interface and is passed down in that
+// capacity to the wrapped balancer. It maintains a set of subConns created by
+// the wrapped balancer and calls from the latter to create/update/remove
+// SubConns update this set before being forwarded to the parent ClientConn.
+// State updates from the wrapped balancer can result in invocation of the
+// graceful switch logic.
+type balancerWrapper struct {
+	balancer.Balancer
+	gsb *Balancer
+
+	lastState balancer.State
+	subconns  map[balancer.SubConn]bool // subconns created by this balancer
+}
+
+func (bw *balancerWrapper) UpdateSubConnState(sc balancer.SubConn, state balancer.SubConnState) {
+	if state.ConnectivityState == connectivity.Shutdown {
+		bw.gsb.mu.Lock()
+		delete(bw.subconns, sc)
+		bw.gsb.mu.Unlock()
+	}
+	// There is no need to protect this read with a mutex, as the write to the
+	// Balancer field happens in SwitchTo, which completes before this can be
+	// called.
+	bw.Balancer.UpdateSubConnState(sc, state)
+}
+
+// Close closes the underlying LB policy and removes the subconns it created. bw
+// must not be referenced via balancerCurrent or balancerPending in gsb when
+// called. gsb.mu must not be held.  Does not panic with a nil receiver.
+func (bw *balancerWrapper) Close() {
+	// before Close is called.
+	if bw == nil {
+		return
+	}
+	// There is no need to protect this read with a mutex, as Close() is
+	// impossible to be called concurrently with the write in SwitchTo(). The
+	// callsites of Close() for this balancer in Graceful Switch Balancer will
+	// never be called until SwitchTo() returns.
+	bw.Balancer.Close()
+	bw.gsb.mu.Lock()
+	for sc := range bw.subconns {
+		bw.gsb.cc.RemoveSubConn(sc)
+	}
+	bw.gsb.mu.Unlock()
+}
+
+func (bw *balancerWrapper) UpdateState(state balancer.State) {
+	// Hold the mutex for this entire call to ensure it cannot occur
+	// concurrently with other updateState() calls. This causes updates to
+	// lastState and calls to cc.UpdateState to happen atomically.
+	bw.gsb.mu.Lock()
+	defer bw.gsb.mu.Unlock()
+	bw.lastState = state
+
+	if !bw.gsb.balancerCurrentOrPending(bw) {
+		return
+	}
+
+	if bw == bw.gsb.balancerCurrent {
+		// In the case that the current balancer exits READY, and there is a pending
+		// balancer, you can forward the pending balancer's cached State up to
+		// ClientConn and swap the pending into the current. This is because there
+		// is no reason to gracefully switch from and keep using the old policy as
+		// the ClientConn is not connected to any backends.
+		if state.ConnectivityState != connectivity.Ready && bw.gsb.balancerPending != nil {
+			bw.gsb.swap()
+			return
+		}
+		// Even if there is a pending balancer waiting to be gracefully switched to,
+		// continue to forward current balancer updates to the Client Conn. Ignoring
+		// state + picker from the current would cause undefined behavior/cause the
+		// system to behave incorrectly from the current LB policies perspective.
+		// Also, the current LB is still being used by grpc to choose SubConns per
+		// RPC, and thus should use the most updated form of the current balancer.
+		bw.gsb.cc.UpdateState(state)
+		return
+	}
+	// This method is now dealing with a state update from the pending balancer.
+	// If the current balancer is currently in a state other than READY, the new
+	// policy can be swapped into place immediately. This is because there is no
+	// reason to gracefully switch from and keep using the old policy as the
+	// ClientConn is not connected to any backends.
+	if state.ConnectivityState != connectivity.Connecting || bw.gsb.balancerCurrent.lastState.ConnectivityState != connectivity.Ready {
+		bw.gsb.swap()
+	}
+}
+
+func (bw *balancerWrapper) NewSubConn(addrs []resolver.Address, opts balancer.NewSubConnOptions) (balancer.SubConn, error) {
+	bw.gsb.mu.Lock()
+	if !bw.gsb.balancerCurrentOrPending(bw) {
+		bw.gsb.mu.Unlock()
+		return nil, fmt.Errorf("%T at address %p that called NewSubConn is deleted", bw, bw)
+	}
+	bw.gsb.mu.Unlock()
+
+	sc, err := bw.gsb.cc.NewSubConn(addrs, opts)
+	if err != nil {
+		return nil, err
+	}
+	bw.gsb.mu.Lock()
+	if !bw.gsb.balancerCurrentOrPending(bw) { // balancer was closed during this call
+		bw.gsb.cc.RemoveSubConn(sc)
+		bw.gsb.mu.Unlock()
+		return nil, fmt.Errorf("%T at address %p that called NewSubConn is deleted", bw, bw)
+	}
+	bw.subconns[sc] = true
+	bw.gsb.mu.Unlock()
+	return sc, nil
+}
+
+func (bw *balancerWrapper) ResolveNow(opts resolver.ResolveNowOptions) {
+	// Ignore ResolveNow requests from anything other than the most recent
+	// balancer, because older balancers were already removed from the config.
+	if bw != bw.gsb.latestBalancer() {
+		return
+	}
+	bw.gsb.cc.ResolveNow(opts)
+}
+
+func (bw *balancerWrapper) RemoveSubConn(sc balancer.SubConn) {
+	bw.gsb.mu.Lock()
+	if !bw.gsb.balancerCurrentOrPending(bw) {
+		bw.gsb.mu.Unlock()
+		return
+	}
+	bw.gsb.mu.Unlock()
+	bw.gsb.cc.RemoveSubConn(sc)
+}
+
+func (bw *balancerWrapper) UpdateAddresses(sc balancer.SubConn, addrs []resolver.Address) {
+	bw.gsb.mu.Lock()
+	if !bw.gsb.balancerCurrentOrPending(bw) {
+		bw.gsb.mu.Unlock()
+		return
+	}
+	bw.gsb.mu.Unlock()
+	bw.gsb.cc.UpdateAddresses(sc, addrs)
+}
+
+func (bw *balancerWrapper) Target() string {
+	return bw.gsb.cc.Target()
+}

vendor/google.golang.org/grpc/internal/binarylog/binarylog.go

@@ -25,12 +25,13 @@ import (
 	"os"
 
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal/grpcutil"
 )
 
 // Logger is the global binary logger. It can be used to get binary logger for
 // each method.
 type Logger interface {
-	getMethodLogger(methodName string) *MethodLogger
+	GetMethodLogger(methodName string) MethodLogger
 }
 
 // binLogger is the global binary logger for the binary. One of this should be
@@ -39,24 +40,33 @@ type Logger interface {
 // It is used to get a methodLogger for each individual method.
 var binLogger Logger
 
-// SetLogger sets the binarg logger.
+var grpclogLogger = grpclog.Component("binarylog")
+
+// SetLogger sets the binary logger.
 //
 // Only call this at init time.
 func SetLogger(l Logger) {
 	binLogger = l
 }
 
+// GetLogger gets the binary logger.
+//
+// Only call this at init time.
+func GetLogger() Logger {
+	return binLogger
+}
+
 // GetMethodLogger returns the methodLogger for the given methodName.
 //
 // methodName should be in the format of "/service/method".
 //
 // Each methodLogger returned by this method is a new instance. This is to
 // generate sequence id within the call.
-func GetMethodLogger(methodName string) *MethodLogger {
+func GetMethodLogger(methodName string) MethodLogger {
 	if binLogger == nil {
 		return nil
 	}
-	return binLogger.getMethodLogger(methodName)
+	return binLogger.GetMethodLogger(methodName)
 }
 
 func init() {
@@ -65,17 +75,29 @@ func init() {
 	binLogger = NewLoggerFromConfigString(configStr)
 }
 
-type methodLoggerConfig struct {
+// MethodLoggerConfig contains the setting for logging behavior of a method
+// logger. Currently, it contains the max length of header and message.
+type MethodLoggerConfig struct {
 	// Max length of header and message.
-	hdr, msg uint64
+	Header, Message uint64
+}
+
+// LoggerConfig contains the config for loggers to create method loggers.
+type LoggerConfig struct {
+	All      *MethodLoggerConfig
+	Services map[string]*MethodLoggerConfig
+	Methods  map[string]*MethodLoggerConfig
+
+	Blacklist map[string]struct{}
 }
 
 type logger struct {
-	all      *methodLoggerConfig
-	services map[string]*methodLoggerConfig
-	methods  map[string]*methodLoggerConfig
+	config LoggerConfig
+}
 
-	blacklist map[string]struct{}
+// NewLoggerFromConfig builds a logger with the given LoggerConfig.
+func NewLoggerFromConfig(config LoggerConfig) Logger {
+	return &logger{config: config}
 }
 
 // newEmptyLogger creates an empty logger. The map fields need to be filled in
@@ -85,57 +107,57 @@ func newEmptyLogger() *logger {
 }
 
 // Set method logger for "*".
-func (l *logger) setDefaultMethodLogger(ml *methodLoggerConfig) error {
-	if l.all != nil {
+func (l *logger) setDefaultMethodLogger(ml *MethodLoggerConfig) error {
+	if l.config.All != nil {
 		return fmt.Errorf("conflicting global rules found")
 	}
-	l.all = ml
+	l.config.All = ml
 	return nil
 }
 
 // Set method logger for "service/*".
 //
 // New methodLogger with same service overrides the old one.
-func (l *logger) setServiceMethodLogger(service string, ml *methodLoggerConfig) error {
-	if _, ok := l.services[service]; ok {
+func (l *logger) setServiceMethodLogger(service string, ml *MethodLoggerConfig) error {
+	if _, ok := l.config.Services[service]; ok {
 		return fmt.Errorf("conflicting service rules for service %v found", service)
 	}
-	if l.services == nil {
-		l.services = make(map[string]*methodLoggerConfig)
+	if l.config.Services == nil {
+		l.config.Services = make(map[string]*MethodLoggerConfig)
 	}
-	l.services[service] = ml
+	l.config.Services[service] = ml
 	return nil
 }
 
 // Set method logger for "service/method".
 //
 // New methodLogger with same method overrides the old one.
-func (l *logger) setMethodMethodLogger(method string, ml *methodLoggerConfig) error {
-	if _, ok := l.blacklist[method]; ok {
+func (l *logger) setMethodMethodLogger(method string, ml *MethodLoggerConfig) error {
+	if _, ok := l.config.Blacklist[method]; ok {
 		return fmt.Errorf("conflicting blacklist rules for method %v found", method)
 	}
-	if _, ok := l.methods[method]; ok {
+	if _, ok := l.config.Methods[method]; ok {
 		return fmt.Errorf("conflicting method rules for method %v found", method)
 	}
-	if l.methods == nil {
-		l.methods = make(map[string]*methodLoggerConfig)
+	if l.config.Methods == nil {
+		l.config.Methods = make(map[string]*MethodLoggerConfig)
 	}
-	l.methods[method] = ml
+	l.config.Methods[method] = ml
 	return nil
 }
 
 // Set blacklist method for "-service/method".
 func (l *logger) setBlacklist(method string) error {
-	if _, ok := l.blacklist[method]; ok {
+	if _, ok := l.config.Blacklist[method]; ok {
 		return fmt.Errorf("conflicting blacklist rules for method %v found", method)
 	}
-	if _, ok := l.methods[method]; ok {
+	if _, ok := l.config.Methods[method]; ok {
 		return fmt.Errorf("conflicting method rules for method %v found", method)
 	}
-	if l.blacklist == nil {
-		l.blacklist = make(map[string]struct{})
+	if l.config.Blacklist == nil {
+		l.config.Blacklist = make(map[string]struct{})
 	}
-	l.blacklist[method] = struct{}{}
+	l.config.Blacklist[method] = struct{}{}
 	return nil
 }
 
@@ -145,23 +167,23 @@ func (l *logger) setBlacklist(method string) error {
 //
 // Each methodLogger returned by this method is a new instance. This is to
 // generate sequence id within the call.
-func (l *logger) getMethodLogger(methodName string) *MethodLogger {
-	s, m, err := parseMethodName(methodName)
+func (l *logger) GetMethodLogger(methodName string) MethodLogger {
+	s, m, err := grpcutil.ParseMethod(methodName)
 	if err != nil {
-		grpclog.Infof("binarylogging: failed to parse %q: %v", methodName, err)
+		grpclogLogger.Infof("binarylogging: failed to parse %q: %v", methodName, err)
 		return nil
 	}
-	if ml, ok := l.methods[s+"/"+m]; ok {
-		return newMethodLogger(ml.hdr, ml.msg)
+	if ml, ok := l.config.Methods[s+"/"+m]; ok {
+		return newMethodLogger(ml.Header, ml.Message)
 	}
-	if _, ok := l.blacklist[s+"/"+m]; ok {
+	if _, ok := l.config.Blacklist[s+"/"+m]; ok {
 		return nil
 	}
-	if ml, ok := l.services[s]; ok {
-		return newMethodLogger(ml.hdr, ml.msg)
+	if ml, ok := l.config.Services[s]; ok {
+		return newMethodLogger(ml.Header, ml.Message)
 	}
-	if l.all == nil {
+	if l.config.All == nil {
 		return nil
 	}
-	return newMethodLogger(l.all.hdr, l.all.msg)
+	return newMethodLogger(l.config.All.Header, l.config.All.Message)
 }

vendor/google.golang.org/grpc/internal/binarylog/env_config.go

@@ -24,8 +24,6 @@ import (
 	"regexp"
 	"strconv"
 	"strings"
-
-	"google.golang.org/grpc/grpclog"
 )
 
 // NewLoggerFromConfigString reads the string and build a logger. It can be used
@@ -52,7 +50,7 @@ func NewLoggerFromConfigString(s string) Logger {
 	methods := strings.Split(s, ",")
 	for _, method := range methods {
 		if err := l.fillMethodLoggerWithConfigString(method); err != nil {
-			grpclog.Warningf("failed to parse binary log config: %v", err)
+			grpclogLogger.Warningf("failed to parse binary log config: %v", err)
 			return nil
 		}
 	}
@@ -91,7 +89,7 @@ func (l *logger) fillMethodLoggerWithConfigString(config string) error {
 		if err != nil {
 			return fmt.Errorf("invalid config: %q, %v", config, err)
 		}
-		if err := l.setDefaultMethodLogger(&methodLoggerConfig{hdr: hdr, msg: msg}); err != nil {
+		if err := l.setDefaultMethodLogger(&MethodLoggerConfig{Header: hdr, Message: msg}); err != nil {
 			return fmt.Errorf("invalid config: %v", err)
 		}
 		return nil
@@ -106,11 +104,11 @@ func (l *logger) fillMethodLoggerWithConfigString(config string) error {
 		return fmt.Errorf("invalid header/message length config: %q, %v", suffix, err)
 	}
 	if m == "*" {
-		if err := l.setServiceMethodLogger(s, &methodLoggerConfig{hdr: hdr, msg: msg}); err != nil {
+		if err := l.setServiceMethodLogger(s, &MethodLoggerConfig{Header: hdr, Message: msg}); err != nil {
 			return fmt.Errorf("invalid config: %v", err)
 		}
 	} else {
-		if err := l.setMethodMethodLogger(s+"/"+m, &methodLoggerConfig{hdr: hdr, msg: msg}); err != nil {
+		if err := l.setMethodMethodLogger(s+"/"+m, &MethodLoggerConfig{Header: hdr, Message: msg}); err != nil {
 			return fmt.Errorf("invalid config: %v", err)
 		}
 	}

vendor/google.golang.org/grpc/internal/binarylog/method_logger.go

@@ -27,7 +27,6 @@ import (
 	"github.com/golang/protobuf/proto"
 	"github.com/golang/protobuf/ptypes"
 	pb "google.golang.org/grpc/binarylog/grpc_binarylog_v1"
-	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/status"
 )
@@ -49,7 +48,11 @@ func (g *callIDGenerator) reset() {
 var idGen callIDGenerator
 
 // MethodLogger is the sub-logger for each method.
-type MethodLogger struct {
+type MethodLogger interface {
+	Log(LogEntryConfig)
+}
+
+type methodLogger struct {
 	headerMaxLen, messageMaxLen uint64
 
 	callID          uint64
@@ -58,20 +61,22 @@ type MethodLogger struct {
 	sink Sink // TODO(blog): make this plugable.
 }
 
-func newMethodLogger(h, m uint64) *MethodLogger {
-	return &MethodLogger{
+func newMethodLogger(h, m uint64) *methodLogger {
+	return &methodLogger{
 		headerMaxLen:  h,
 		messageMaxLen: m,
 
 		callID:          idGen.next(),
 		idWithinCallGen: &callIDGenerator{},
 
-		sink: defaultSink, // TODO(blog): make it plugable.
+		sink: DefaultSink, // TODO(blog): make it plugable.
 	}
 }
 
-// Log creates a proto binary log entry, and logs it to the sink.
-func (ml *MethodLogger) Log(c LogEntryConfig) {
+// Build is an internal only method for building the proto message out of the
+// input event. It's made public to enable other library to reuse as much logic
+// in methodLogger as possible.
+func (ml *methodLogger) Build(c LogEntryConfig) *pb.GrpcLogEntry {
 	m := c.toProto()
 	timestamp, _ := ptypes.TimestampProto(time.Now())
 	m.Timestamp = timestamp
@@ -86,11 +91,15 @@ func (ml *MethodLogger) Log(c LogEntryConfig) {
 	case *pb.GrpcLogEntry_Message:
 		m.PayloadTruncated = ml.truncateMessage(pay.Message)
 	}
-
-	ml.sink.Write(m)
+	return m
 }
 
-func (ml *MethodLogger) truncateMetadata(mdPb *pb.Metadata) (truncated bool) {
+// Log creates a proto binary log entry, and logs it to the sink.
+func (ml *methodLogger) Log(c LogEntryConfig) {
+	ml.sink.Write(ml.Build(c))
+}
+
+func (ml *methodLogger) truncateMetadata(mdPb *pb.Metadata) (truncated bool) {
 	if ml.headerMaxLen == maxUInt {
 		return false
 	}
@@ -120,7 +129,7 @@ func (ml *MethodLogger) truncateMetadata(mdPb *pb.Metadata) (truncated bool) {
 	return truncated
 }
 
-func (ml *MethodLogger) truncateMessage(msgPb *pb.Message) (truncated bool) {
+func (ml *methodLogger) truncateMessage(msgPb *pb.Message) (truncated bool) {
 	if ml.messageMaxLen == maxUInt {
 		return false
 	}
@@ -219,12 +228,12 @@ func (c *ClientMessage) toProto() *pb.GrpcLogEntry {
 	if m, ok := c.Message.(proto.Message); ok {
 		data, err = proto.Marshal(m)
 		if err != nil {
-			grpclog.Infof("binarylogging: failed to marshal proto message: %v", err)
+			grpclogLogger.Infof("binarylogging: failed to marshal proto message: %v", err)
 		}
 	} else if b, ok := c.Message.([]byte); ok {
 		data = b
 	} else {
-		grpclog.Infof("binarylogging: message to log is neither proto.message nor []byte")
+		grpclogLogger.Infof("binarylogging: message to log is neither proto.message nor []byte")
 	}
 	ret := &pb.GrpcLogEntry{
 		Type: pb.GrpcLogEntry_EVENT_TYPE_CLIENT_MESSAGE,
@@ -259,12 +268,12 @@ func (c *ServerMessage) toProto() *pb.GrpcLogEntry {
 	if m, ok := c.Message.(proto.Message); ok {
 		data, err = proto.Marshal(m)
 		if err != nil {
-			grpclog.Infof("binarylogging: failed to marshal proto message: %v", err)
+			grpclogLogger.Infof("binarylogging: failed to marshal proto message: %v", err)
 		}
 	} else if b, ok := c.Message.([]byte); ok {
 		data = b
 	} else {
-		grpclog.Infof("binarylogging: message to log is neither proto.message nor []byte")
+		grpclogLogger.Infof("binarylogging: message to log is neither proto.message nor []byte")
 	}
 	ret := &pb.GrpcLogEntry{
 		Type: pb.GrpcLogEntry_EVENT_TYPE_SERVER_MESSAGE,
@@ -315,7 +324,7 @@ type ServerTrailer struct {
 func (c *ServerTrailer) toProto() *pb.GrpcLogEntry {
 	st, ok := status.FromError(c.Err)
 	if !ok {
-		grpclog.Info("binarylogging: error in trailer is not a status error")
+		grpclogLogger.Info("binarylogging: error in trailer is not a status error")
 	}
 	var (
 		detailsBytes []byte
@@ -325,7 +334,7 @@ func (c *ServerTrailer) toProto() *pb.GrpcLogEntry {
 	if stProto != nil && len(stProto.Details) != 0 {
 		detailsBytes, err = proto.Marshal(stProto)
 		if err != nil {
-			grpclog.Infof("binarylogging: failed to marshal status proto: %v", err)
+			grpclogLogger.Infof("binarylogging: failed to marshal status proto: %v", err)
 		}
 	}
 	ret := &pb.GrpcLogEntry{

vendor/google.golang.org/grpc/internal/binarylog/regenerate.sh

@@ -1,33 +0,0 @@
-#!/bin/bash
-# Copyright 2018 gRPC authors.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#      http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-set -eux -o pipefail
-
-TMP=$(mktemp -d)
-
-function finish {
-  rm -rf "$TMP"
-}
-trap finish EXIT
-
-pushd "$TMP"
-mkdir -p grpc/binarylog/grpc_binarylog_v1
-curl https://raw.githubusercontent.com/grpc/grpc-proto/master/grpc/binlog/v1/binarylog.proto > grpc/binarylog/grpc_binarylog_v1/binarylog.proto
-
-protoc --go_out=plugins=grpc,paths=source_relative:. -I. grpc/binarylog/grpc_binarylog_v1/*.proto
-popd
-rm -f ./grpc_binarylog_v1/*.pb.go
-cp "$TMP"/grpc/binarylog/grpc_binarylog_v1/*.pb.go ../../binarylog/grpc_binarylog_v1/
-

vendor/google.golang.org/grpc/internal/binarylog/sink.go

@@ -21,32 +21,23 @@ package binarylog
 import (
 	"bufio"
 	"encoding/binary"
-	"fmt"
 	"io"
-	"io/ioutil"
 	"sync"
 	"time"
 
 	"github.com/golang/protobuf/proto"
 	pb "google.golang.org/grpc/binarylog/grpc_binarylog_v1"
-	"google.golang.org/grpc/grpclog"
 )
 
 var (
-	defaultSink Sink = &noopSink{} // TODO(blog): change this default (file in /tmp).
+	// DefaultSink is the sink where the logs will be written to. It's exported
+	// for the binarylog package to update.
+	DefaultSink Sink = &noopSink{} // TODO(blog): change this default (file in /tmp).
 )
 
-// SetDefaultSink sets the sink where binary logs will be written to.
-//
-// Not thread safe. Only set during initialization.
-func SetDefaultSink(s Sink) {
-	if defaultSink != nil {
-		defaultSink.Close()
-	}
-	defaultSink = s
-}
-
 // Sink writes log entry into the binary log sink.
+//
+// sink is a copy of the exported binarylog.Sink, to avoid circular dependency.
 type Sink interface {
 	// Write will be called to write the log entry into the sink.
 	//
@@ -67,7 +58,7 @@ func (ns *noopSink) Close() error                 { return nil }
 // message is prefixed with a 4 byte big endian unsigned integer as the length.
 //
 // No buffer is done, Close() doesn't try to close the writer.
-func newWriterSink(w io.Writer) *writerSink {
+func newWriterSink(w io.Writer) Sink {
 	return &writerSink{out: w}
 }
 
@@ -78,7 +69,8 @@ type writerSink struct {
 func (ws *writerSink) Write(e *pb.GrpcLogEntry) error {
 	b, err := proto.Marshal(e)
 	if err != nil {
-		grpclog.Infof("binary logging: failed to marshal proto message: %v", err)
+		grpclogLogger.Errorf("binary logging: failed to marshal proto message: %v", err)
+		return err
 	}
 	hdr := make([]byte, 4)
 	binary.BigEndian.PutUint32(hdr, uint32(len(b)))
@@ -93,25 +85,28 @@ func (ws *writerSink) Write(e *pb.GrpcLogEntry) error {
 
 func (ws *writerSink) Close() error { return nil }
 
-type bufWriteCloserSink struct {
-	mu     sync.Mutex
-	closer io.Closer
-	out    *writerSink   // out is built on buf.
-	buf    *bufio.Writer // buf is kept for flush.
+type bufferedSink struct {
+	mu             sync.Mutex
+	closer         io.Closer
+	out            Sink          // out is built on buf.
+	buf            *bufio.Writer // buf is kept for flush.
+	flusherStarted bool
 
-	writeStartOnce sync.Once
-	writeTicker    *time.Ticker
+	writeTicker *time.Ticker
+	done        chan struct{}
 }
 
-func (fs *bufWriteCloserSink) Write(e *pb.GrpcLogEntry) error {
-	// Start the write loop when Write is called.
-	fs.writeStartOnce.Do(fs.startFlushGoroutine)
+func (fs *bufferedSink) Write(e *pb.GrpcLogEntry) error {
 	fs.mu.Lock()
+	defer fs.mu.Unlock()
+	if !fs.flusherStarted {
+		// Start the write loop when Write is called.
+		fs.startFlushGoroutine()
+		fs.flusherStarted = true
+	}
 	if err := fs.out.Write(e); err != nil {
-		fs.mu.Unlock()
 		return err
 	}
-	fs.mu.Unlock()
 	return nil
 }
 
@@ -119,44 +114,57 @@ const (
 	bufFlushDuration = 60 * time.Second
 )
 
-func (fs *bufWriteCloserSink) startFlushGoroutine() {
+func (fs *bufferedSink) startFlushGoroutine() {
 	fs.writeTicker = time.NewTicker(bufFlushDuration)
 	go func() {
-		for range fs.writeTicker.C {
+		for {
+			select {
+			case <-fs.done:
+				return
+			case <-fs.writeTicker.C:
+			}
 			fs.mu.Lock()
-			fs.buf.Flush()
+			if err := fs.buf.Flush(); err != nil {
+				grpclogLogger.Warningf("failed to flush to Sink: %v", err)
+			}
 			fs.mu.Unlock()
 		}
 	}()
 }
 
-func (fs *bufWriteCloserSink) Close() error {
+func (fs *bufferedSink) Close() error {
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
 	if fs.writeTicker != nil {
 		fs.writeTicker.Stop()
 	}
-	fs.mu.Lock()
-	fs.buf.Flush()
-	fs.closer.Close()
-	fs.out.Close()
-	fs.mu.Unlock()
+	close(fs.done)
+	if err := fs.buf.Flush(); err != nil {
+		grpclogLogger.Warningf("failed to flush to Sink: %v", err)
+	}
+	if err := fs.closer.Close(); err != nil {
+		grpclogLogger.Warningf("failed to close the underlying WriterCloser: %v", err)
+	}
+	if err := fs.out.Close(); err != nil {
+		grpclogLogger.Warningf("failed to close the Sink: %v", err)
+	}
 	return nil
 }
 
-func newBufWriteCloserSink(o io.WriteCloser) Sink {
+// NewBufferedSink creates a binary log sink with the given WriteCloser.
+//
+// Write() marshals the proto message and writes it to the given writer. Each
+// message is prefixed with a 4 byte big endian unsigned integer as the length.
+//
+// Content is kept in a buffer, and is flushed every 60 seconds.
+//
+// Close closes the WriteCloser.
+func NewBufferedSink(o io.WriteCloser) Sink {
 	bufW := bufio.NewWriter(o)
-	return &bufWriteCloserSink{
+	return &bufferedSink{
 		closer: o,
 		out:    newWriterSink(bufW),
 		buf:    bufW,
+		done:   make(chan struct{}),
 	}
 }
-
-// NewTempFileSink creates a temp file and returns a Sink that writes to this
-// file.
-func NewTempFileSink() (Sink, error) {
-	tempFile, err := ioutil.TempFile("/tmp", "grpcgo_binarylog_*.txt")
-	if err != nil {
-		return nil, fmt.Errorf("failed to create temp file: %v", err)
-	}
-	return newBufWriteCloserSink(tempFile), nil
-}

vendor/google.golang.org/grpc/internal/binarylog/util.go

@@ -1,41 +0,0 @@
-/*
- *
- * Copyright 2018 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package binarylog
-
-import (
-	"errors"
-	"strings"
-)
-
-// parseMethodName splits service and method from the input. It expects format
-// "/service/method".
-//
-// TODO: move to internal/grpcutil.
-func parseMethodName(methodName string) (service, method string, _ error) {
-	if !strings.HasPrefix(methodName, "/") {
-		return "", "", errors.New("invalid method name: should start with /")
-	}
-	methodName = methodName[1:]
-
-	pos := strings.LastIndex(methodName, "/")
-	if pos < 0 {
-		return "", "", errors.New("invalid method name: suffix /method is missing")
-	}
-	return methodName[:pos], methodName[pos+1:], nil
-}

vendor/google.golang.org/grpc/internal/channelz/funcs.go

@@ -24,6 +24,8 @@
 package channelz
 
 import (
+	"context"
+	"errors"
 	"fmt"
 	"sort"
 	"sync"
@@ -49,7 +51,8 @@ var (
 // TurnOn turns on channelz data collection.
 func TurnOn() {
 	if !IsOn() {
-		NewChannelzStorage()
+		db.set(newChannelMap())
+		idGen.reset()
 		atomic.StoreInt32(&curState, 1)
 	}
 }
@@ -94,46 +97,40 @@ func (d *dbWrapper) get() *channelMap {
 	return d.DB
 }
 
-// NewChannelzStorage initializes channelz data storage and id generator.
+// NewChannelzStorageForTesting initializes channelz data storage and id
+// generator for testing purposes.
 //
-// This function returns a cleanup function to wait for all channelz state to be reset by the
-// grpc goroutines when those entities get closed. By using this cleanup function, we make sure tests
-// don't mess up each other, i.e. lingering goroutine from previous test doing entity removal happen
-// to remove some entity just register by the new test, since the id space is the same.
-//
-// Note: This function is exported for testing purpose only. User should not call
-// it in most cases.
-func NewChannelzStorage() (cleanup func() error) {
-	db.set(&channelMap{
-		topLevelChannels: make(map[int64]struct{}),
-		channels:         make(map[int64]*channel),
-		listenSockets:    make(map[int64]*listenSocket),
-		normalSockets:    make(map[int64]*normalSocket),
-		servers:          make(map[int64]*server),
-		subChannels:      make(map[int64]*subChannel),
-	})
+// Returns a cleanup function to be invoked by the test, which waits for up to
+// 10s for all channelz state to be reset by the grpc goroutines when those
+// entities get closed. This cleanup function helps with ensuring that tests
+// don't mess up each other.
+func NewChannelzStorageForTesting() (cleanup func() error) {
+	db.set(newChannelMap())
 	idGen.reset()
+
 	return func() error {
-		var err error
 		cm := db.get()
 		if cm == nil {
 			return nil
 		}
-		for i := 0; i < 1000; i++ {
-			cm.mu.Lock()
-			if len(cm.topLevelChannels) == 0 && len(cm.servers) == 0 && len(cm.channels) == 0 && len(cm.subChannels) == 0 && len(cm.listenSockets) == 0 && len(cm.normalSockets) == 0 {
-				cm.mu.Unlock()
-				// all things stored in the channelz map have been cleared.
+
+		ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+		defer cancel()
+		ticker := time.NewTicker(10 * time.Millisecond)
+		defer ticker.Stop()
+		for {
+			cm.mu.RLock()
+			topLevelChannels, servers, channels, subChannels, listenSockets, normalSockets := len(cm.topLevelChannels), len(cm.servers), len(cm.channels), len(cm.subChannels), len(cm.listenSockets), len(cm.normalSockets)
+			cm.mu.RUnlock()
+
+			if err := ctx.Err(); err != nil {
+				return fmt.Errorf("after 10s the channelz map has not been cleaned up yet, topchannels: %d, servers: %d, channels: %d, subchannels: %d, listen sockets: %d, normal sockets: %d", topLevelChannels, servers, channels, subChannels, listenSockets, normalSockets)
+			}
+			if topLevelChannels == 0 && servers == 0 && channels == 0 && subChannels == 0 && listenSockets == 0 && normalSockets == 0 {
 				return nil
 			}
-			cm.mu.Unlock()
-			time.Sleep(10 * time.Millisecond)
+			<-ticker.C
 		}
-
-		cm.mu.Lock()
-		err = fmt.Errorf("after 10s the channelz map has not been cleaned up yet, topchannels: %d, servers: %d, channels: %d, subchannels: %d, listen sockets: %d, normal sockets: %d", len(cm.topLevelChannels), len(cm.servers), len(cm.channels), len(cm.subChannels), len(cm.listenSockets), len(cm.normalSockets))
-		cm.mu.Unlock()
-		return err
 	}
 }
 
@@ -188,54 +185,77 @@ func GetServer(id int64) *ServerMetric {
 	return db.get().GetServer(id)
 }
 
-// RegisterChannel registers the given channel c in channelz database with ref
-// as its reference name, and add it to the child list of its parent (identified
-// by pid). pid = 0 means no parent. It returns the unique channelz tracking id
-// assigned to this channel.
-func RegisterChannel(c Channel, pid int64, ref string) int64 {
+// RegisterChannel registers the given channel c in the channelz database with
+// ref as its reference name, and adds it to the child list of its parent
+// (identified by pid). pid == nil means no parent.
+//
+// Returns a unique channelz identifier assigned to this channel.
+//
+// If channelz is not turned ON, the channelz database is not mutated.
+func RegisterChannel(c Channel, pid *Identifier, ref string) *Identifier {
 	id := idGen.genID()
+	var parent int64
+	isTopChannel := true
+	if pid != nil {
+		isTopChannel = false
+		parent = pid.Int()
+	}
+
+	if !IsOn() {
+		return newIdentifer(RefChannel, id, pid)
+	}
+
 	cn := &channel{
 		refName:     ref,
 		c:           c,
 		subChans:    make(map[int64]string),
 		nestedChans: make(map[int64]string),
 		id:          id,
-		pid:         pid,
+		pid:         parent,
 		trace:       &channelTrace{createdTime: time.Now(), events: make([]*TraceEvent, 0, getMaxTraceEntry())},
 	}
-	if pid == 0 {
-		db.get().addChannel(id, cn, true, pid, ref)
-	} else {
-		db.get().addChannel(id, cn, false, pid, ref)
-	}
-	return id
+	db.get().addChannel(id, cn, isTopChannel, parent)
+	return newIdentifer(RefChannel, id, pid)
 }
 
-// RegisterSubChannel registers the given channel c in channelz database with ref
-// as its reference name, and add it to the child list of its parent (identified
-// by pid). It returns the unique channelz tracking id assigned to this subchannel.
-func RegisterSubChannel(c Channel, pid int64, ref string) int64 {
-	if pid == 0 {
-		grpclog.Error("a SubChannel's parent id cannot be 0")
-		return 0
+// RegisterSubChannel registers the given subChannel c in the channelz database
+// with ref as its reference name, and adds it to the child list of its parent
+// (identified by pid).
+//
+// Returns a unique channelz identifier assigned to this subChannel.
+//
+// If channelz is not turned ON, the channelz database is not mutated.
+func RegisterSubChannel(c Channel, pid *Identifier, ref string) (*Identifier, error) {
+	if pid == nil {
+		return nil, errors.New("a SubChannel's parent id cannot be nil")
 	}
 	id := idGen.genID()
+	if !IsOn() {
+		return newIdentifer(RefSubChannel, id, pid), nil
+	}
+
 	sc := &subChannel{
 		refName: ref,
 		c:       c,
 		sockets: make(map[int64]string),
 		id:      id,
-		pid:     pid,
+		pid:     pid.Int(),
 		trace:   &channelTrace{createdTime: time.Now(), events: make([]*TraceEvent, 0, getMaxTraceEntry())},
 	}
-	db.get().addSubChannel(id, sc, pid, ref)
-	return id
+	db.get().addSubChannel(id, sc, pid.Int())
+	return newIdentifer(RefSubChannel, id, pid), nil
 }
 
 // RegisterServer registers the given server s in channelz database. It returns
 // the unique channelz tracking id assigned to this server.
-func RegisterServer(s Server, ref string) int64 {
+//
+// If channelz is not turned ON, the channelz database is not mutated.
+func RegisterServer(s Server, ref string) *Identifier {
 	id := idGen.genID()
+	if !IsOn() {
+		return newIdentifer(RefServer, id, nil)
+	}
+
 	svr := &server{
 		refName:       ref,
 		s:             s,
@@ -244,61 +264,92 @@ func RegisterServer(s Server, ref string) int64 {
 		id:            id,
 	}
 	db.get().addServer(id, svr)
-	return id
+	return newIdentifer(RefServer, id, nil)
 }
 
 // RegisterListenSocket registers the given listen socket s in channelz database
 // with ref as its reference name, and add it to the child list of its parent
 // (identified by pid). It returns the unique channelz tracking id assigned to
 // this listen socket.
-func RegisterListenSocket(s Socket, pid int64, ref string) int64 {
-	if pid == 0 {
-		grpclog.Error("a ListenSocket's parent id cannot be 0")
-		return 0
+//
+// If channelz is not turned ON, the channelz database is not mutated.
+func RegisterListenSocket(s Socket, pid *Identifier, ref string) (*Identifier, error) {
+	if pid == nil {
+		return nil, errors.New("a ListenSocket's parent id cannot be 0")
 	}
 	id := idGen.genID()
-	ls := &listenSocket{refName: ref, s: s, id: id, pid: pid}
-	db.get().addListenSocket(id, ls, pid, ref)
-	return id
+	if !IsOn() {
+		return newIdentifer(RefListenSocket, id, pid), nil
+	}
+
+	ls := &listenSocket{refName: ref, s: s, id: id, pid: pid.Int()}
+	db.get().addListenSocket(id, ls, pid.Int())
+	return newIdentifer(RefListenSocket, id, pid), nil
 }
 
 // RegisterNormalSocket registers the given normal socket s in channelz database
-// with ref as its reference name, and add it to the child list of its parent
+// with ref as its reference name, and adds it to the child list of its parent
 // (identified by pid). It returns the unique channelz tracking id assigned to
 // this normal socket.
-func RegisterNormalSocket(s Socket, pid int64, ref string) int64 {
-	if pid == 0 {
-		grpclog.Error("a NormalSocket's parent id cannot be 0")
-		return 0
+//
+// If channelz is not turned ON, the channelz database is not mutated.
+func RegisterNormalSocket(s Socket, pid *Identifier, ref string) (*Identifier, error) {
+	if pid == nil {
+		return nil, errors.New("a NormalSocket's parent id cannot be 0")
 	}
 	id := idGen.genID()
-	ns := &normalSocket{refName: ref, s: s, id: id, pid: pid}
-	db.get().addNormalSocket(id, ns, pid, ref)
-	return id
+	if !IsOn() {
+		return newIdentifer(RefNormalSocket, id, pid), nil
+	}
+
+	ns := &normalSocket{refName: ref, s: s, id: id, pid: pid.Int()}
+	db.get().addNormalSocket(id, ns, pid.Int())
+	return newIdentifer(RefNormalSocket, id, pid), nil
 }
 
-// RemoveEntry removes an entry with unique channelz trakcing id to be id from
+// RemoveEntry removes an entry with unique channelz tracking id to be id from
 // channelz database.
-func RemoveEntry(id int64) {
-	db.get().removeEntry(id)
+//
+// If channelz is not turned ON, this function is a no-op.
+func RemoveEntry(id *Identifier) {
+	if !IsOn() {
+		return
+	}
+	db.get().removeEntry(id.Int())
 }
 
-// TraceEventDesc is what the caller of AddTraceEvent should provide to describe the event to be added
-// to the channel trace.
-// The Parent field is optional. It is used for event that will be recorded in the entity's parent
-// trace also.
+// TraceEventDesc is what the caller of AddTraceEvent should provide to describe
+// the event to be added to the channel trace.
+//
+// The Parent field is optional. It is used for an event that will be recorded
+// in the entity's parent trace.
 type TraceEventDesc struct {
 	Desc     string
 	Severity Severity
 	Parent   *TraceEventDesc
 }
 
-// AddTraceEvent adds trace related to the entity with specified id, using the provided TraceEventDesc.
-func AddTraceEvent(id int64, desc *TraceEventDesc) {
+// AddTraceEvent adds trace related to the entity with specified id, using the
+// provided TraceEventDesc.
+//
+// If channelz is not turned ON, this will simply log the event descriptions.
+func AddTraceEvent(l grpclog.DepthLoggerV2, id *Identifier, depth int, desc *TraceEventDesc) {
+	// Log only the trace description associated with the bottom most entity.
+	switch desc.Severity {
+	case CtUnknown, CtInfo:
+		l.InfoDepth(depth+1, withParens(id)+desc.Desc)
+	case CtWarning:
+		l.WarningDepth(depth+1, withParens(id)+desc.Desc)
+	case CtError:
+		l.ErrorDepth(depth+1, withParens(id)+desc.Desc)
+	}
+
 	if getMaxTraceEntry() == 0 {
 		return
 	}
-	db.get().traceEvent(id, desc)
+	if IsOn() {
+		db.get().traceEvent(id.Int(), desc)
+	}
 }
 
 // channelMap is the storage data structure for channelz.
@@ -316,6 +367,17 @@ type channelMap struct {
 	normalSockets    map[int64]*normalSocket
 }
 
+func newChannelMap() *channelMap {
+	return &channelMap{
+		topLevelChannels: make(map[int64]struct{}),
+		channels:         make(map[int64]*channel),
+		listenSockets:    make(map[int64]*listenSocket),
+		normalSockets:    make(map[int64]*normalSocket),
+		servers:          make(map[int64]*server),
+		subChannels:      make(map[int64]*subChannel),
+	}
+}
+
 func (c *channelMap) addServer(id int64, s *server) {
 	c.mu.Lock()
 	s.cm = c
@@ -323,7 +385,7 @@ func (c *channelMap) addServer(id int64, s *server) {
 	c.mu.Unlock()
 }
 
-func (c *channelMap) addChannel(id int64, cn *channel, isTopChannel bool, pid int64, ref string) {
+func (c *channelMap) addChannel(id int64, cn *channel, isTopChannel bool, pid int64) {
 	c.mu.Lock()
 	cn.cm = c
 	cn.trace.cm = c
@@ -336,7 +398,7 @@ func (c *channelMap) addChannel(id int64, cn *channel, isTopChannel bool, pid in
 	c.mu.Unlock()
 }
 
-func (c *channelMap) addSubChannel(id int64, sc *subChannel, pid int64, ref string) {
+func (c *channelMap) addSubChannel(id int64, sc *subChannel, pid int64) {
 	c.mu.Lock()
 	sc.cm = c
 	sc.trace.cm = c
@@ -345,7 +407,7 @@ func (c *channelMap) addSubChannel(id int64, sc *subChannel, pid int64, ref stri
 	c.mu.Unlock()
 }
 
-func (c *channelMap) addListenSocket(id int64, ls *listenSocket, pid int64, ref string) {
+func (c *channelMap) addListenSocket(id int64, ls *listenSocket, pid int64) {
 	c.mu.Lock()
 	ls.cm = c
 	c.listenSockets[id] = ls
@@ -353,7 +415,7 @@ func (c *channelMap) addListenSocket(id int64, ls *listenSocket, pid int64, ref
 	c.mu.Unlock()
 }
 
-func (c *channelMap) addNormalSocket(id int64, ns *normalSocket, pid int64, ref string) {
+func (c *channelMap) addNormalSocket(id int64, ns *normalSocket, pid int64) {
 	c.mu.Lock()
 	ns.cm = c
 	c.normalSockets[id] = ns
@@ -620,7 +682,7 @@ func (c *channelMap) GetServerSockets(id int64, startID int64, maxResults int64)
 	if count == 0 {
 		end = true
 	}
-	var s []*SocketMetric
+	s := make([]*SocketMetric, 0, len(sks))
 	for _, ns := range sks {
 		sm := &SocketMetric{}
 		sm.SocketData = ns.s.ChannelzMetric()

vendor/google.golang.org/grpc/internal/channelz/id.go

@@ -0,0 +1,75 @@
+/*
+ *
+ * Copyright 2022 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package channelz
+
+import "fmt"
+
+// Identifier is an opaque identifier which uniquely identifies an entity in the
+// channelz database.
+type Identifier struct {
+	typ RefChannelType
+	id  int64
+	str string
+	pid *Identifier
+}
+
+// Type returns the entity type corresponding to id.
+func (id *Identifier) Type() RefChannelType {
+	return id.typ
+}
+
+// Int returns the integer identifier corresponding to id.
+func (id *Identifier) Int() int64 {
+	return id.id
+}
+
+// String returns a string representation of the entity corresponding to id.
+//
+// This includes some information about the parent as well. Examples:
+// Top-level channel: [Channel #channel-number]
+// Nested channel:    [Channel #parent-channel-number Channel #channel-number]
+// Sub channel:       [Channel #parent-channel SubChannel #subchannel-number]
+func (id *Identifier) String() string {
+	return id.str
+}
+
+// Equal returns true if other is the same as id.
+func (id *Identifier) Equal(other *Identifier) bool {
+	if (id != nil) != (other != nil) {
+		return false
+	}
+	if id == nil && other == nil {
+		return true
+	}
+	return id.typ == other.typ && id.id == other.id && id.pid == other.pid
+}
+
+// NewIdentifierForTesting returns a new opaque identifier to be used only for
+// testing purposes.
+func NewIdentifierForTesting(typ RefChannelType, id int64, pid *Identifier) *Identifier {
+	return newIdentifer(typ, id, pid)
+}
+
+func newIdentifer(typ RefChannelType, id int64, pid *Identifier) *Identifier {
+	str := fmt.Sprintf("%s #%d", typ, id)
+	if pid != nil {
+		str = fmt.Sprintf("%s %s", pid, str)
+	}
+	return &Identifier{typ: typ, id: id, str: str, pid: pid}
+}

vendor/google.golang.org/grpc/internal/channelz/logging.go

@@ -0,0 +1,79 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package channelz
+
+import (
+	"fmt"
+
+	"google.golang.org/grpc/grpclog"
+)
+
+var logger = grpclog.Component("channelz")
+
+func withParens(id *Identifier) string {
+	return "[" + id.String() + "] "
+}
+
+// Info logs and adds a trace event if channelz is on.
+func Info(l grpclog.DepthLoggerV2, id *Identifier, args ...interface{}) {
+	AddTraceEvent(l, id, 1, &TraceEventDesc{
+		Desc:     fmt.Sprint(args...),
+		Severity: CtInfo,
+	})
+}
+
+// Infof logs and adds a trace event if channelz is on.
+func Infof(l grpclog.DepthLoggerV2, id *Identifier, format string, args ...interface{}) {
+	AddTraceEvent(l, id, 1, &TraceEventDesc{
+		Desc:     fmt.Sprintf(format, args...),
+		Severity: CtInfo,
+	})
+}
+
+// Warning logs and adds a trace event if channelz is on.
+func Warning(l grpclog.DepthLoggerV2, id *Identifier, args ...interface{}) {
+	AddTraceEvent(l, id, 1, &TraceEventDesc{
+		Desc:     fmt.Sprint(args...),
+		Severity: CtWarning,
+	})
+}
+
+// Warningf logs and adds a trace event if channelz is on.
+func Warningf(l grpclog.DepthLoggerV2, id *Identifier, format string, args ...interface{}) {
+	AddTraceEvent(l, id, 1, &TraceEventDesc{
+		Desc:     fmt.Sprintf(format, args...),
+		Severity: CtWarning,
+	})
+}
+
+// Error logs and adds a trace event if channelz is on.
+func Error(l grpclog.DepthLoggerV2, id *Identifier, args ...interface{}) {
+	AddTraceEvent(l, id, 1, &TraceEventDesc{
+		Desc:     fmt.Sprint(args...),
+		Severity: CtError,
+	})
+}
+
+// Errorf logs and adds a trace event if channelz is on.
+func Errorf(l grpclog.DepthLoggerV2, id *Identifier, format string, args ...interface{}) {
+	AddTraceEvent(l, id, 1, &TraceEventDesc{
+		Desc:     fmt.Sprintf(format, args...),
+		Severity: CtError,
+	})
+}

vendor/google.golang.org/grpc/internal/channelz/types.go

@@ -26,7 +26,6 @@ import (
 
 	"google.golang.org/grpc/connectivity"
 	"google.golang.org/grpc/credentials"
-	"google.golang.org/grpc/grpclog"
 )
 
 // entry represents a node in the channelz database.
@@ -60,17 +59,17 @@ func (d *dummyEntry) addChild(id int64, e entry) {
 	// the addrConn will create a new transport. And when registering the new transport in
 	// channelz, its parent addrConn could have already been torn down and deleted
 	// from channelz tracking, and thus reach the code here.
-	grpclog.Infof("attempt to add child of type %T with id %d to a parent (id=%d) that doesn't currently exist", e, id, d.idNotFound)
+	logger.Infof("attempt to add child of type %T with id %d to a parent (id=%d) that doesn't currently exist", e, id, d.idNotFound)
 }
 
 func (d *dummyEntry) deleteChild(id int64) {
 	// It is possible for a normal program to reach here under race condition.
 	// Refer to the example described in addChild().
-	grpclog.Infof("attempt to delete child with id %d from a parent (id=%d) that doesn't currently exist", id, d.idNotFound)
+	logger.Infof("attempt to delete child with id %d from a parent (id=%d) that doesn't currently exist", id, d.idNotFound)
 }
 
 func (d *dummyEntry) triggerDelete() {
-	grpclog.Warningf("attempt to delete an entry (id=%d) that doesn't currently exist", d.idNotFound)
+	logger.Warningf("attempt to delete an entry (id=%d) that doesn't currently exist", d.idNotFound)
 }
 
 func (*dummyEntry) deleteSelfIfReady() {
@@ -215,7 +214,7 @@ func (c *channel) addChild(id int64, e entry) {
 	case *channel:
 		c.nestedChans[id] = v.refName
 	default:
-		grpclog.Errorf("cannot add a child (id = %d) of type %T to a channel", id, e)
+		logger.Errorf("cannot add a child (id = %d) of type %T to a channel", id, e)
 	}
 }
 
@@ -326,7 +325,7 @@ func (sc *subChannel) addChild(id int64, e entry) {
 	if v, ok := e.(*normalSocket); ok {
 		sc.sockets[id] = v.refName
 	} else {
-		grpclog.Errorf("cannot add a child (id = %d) of type %T to a subChannel", id, e)
+		logger.Errorf("cannot add a child (id = %d) of type %T to a subChannel", id, e)
 	}
 }
 
@@ -493,11 +492,11 @@ type listenSocket struct {
 }
 
 func (ls *listenSocket) addChild(id int64, e entry) {
-	grpclog.Errorf("cannot add a child (id = %d) of type %T to a listen socket", id, e)
+	logger.Errorf("cannot add a child (id = %d) of type %T to a listen socket", id, e)
 }
 
 func (ls *listenSocket) deleteChild(id int64) {
-	grpclog.Errorf("cannot delete a child (id = %d) from a listen socket", id)
+	logger.Errorf("cannot delete a child (id = %d) from a listen socket", id)
 }
 
 func (ls *listenSocket) triggerDelete() {
@@ -506,7 +505,7 @@ func (ls *listenSocket) triggerDelete() {
 }
 
 func (ls *listenSocket) deleteSelfIfReady() {
-	grpclog.Errorf("cannot call deleteSelfIfReady on a listen socket")
+	logger.Errorf("cannot call deleteSelfIfReady on a listen socket")
 }
 
 func (ls *listenSocket) getParentID() int64 {
@@ -522,11 +521,11 @@ type normalSocket struct {
 }
 
 func (ns *normalSocket) addChild(id int64, e entry) {
-	grpclog.Errorf("cannot add a child (id = %d) of type %T to a normal socket", id, e)
+	logger.Errorf("cannot add a child (id = %d) of type %T to a normal socket", id, e)
 }
 
 func (ns *normalSocket) deleteChild(id int64) {
-	grpclog.Errorf("cannot delete a child (id = %d) from a normal socket", id)
+	logger.Errorf("cannot delete a child (id = %d) from a normal socket", id)
 }
 
 func (ns *normalSocket) triggerDelete() {
@@ -535,7 +534,7 @@ func (ns *normalSocket) triggerDelete() {
 }
 
 func (ns *normalSocket) deleteSelfIfReady() {
-	grpclog.Errorf("cannot call deleteSelfIfReady on a normal socket")
+	logger.Errorf("cannot call deleteSelfIfReady on a normal socket")
 }
 
 func (ns *normalSocket) getParentID() int64 {
@@ -594,7 +593,7 @@ func (s *server) addChild(id int64, e entry) {
 	case *listenSocket:
 		s.listenSockets[id] = v.refName
 	default:
-		grpclog.Errorf("cannot add a child (id = %d) of type %T to a server", id, e)
+		logger.Errorf("cannot add a child (id = %d) of type %T to a server", id, e)
 	}
 }
 
@@ -673,10 +672,10 @@ func (c *channelTrace) clear() {
 type Severity int
 
 const (
-	// CtUNKNOWN indicates unknown severity of a trace event.
-	CtUNKNOWN Severity = iota
-	// CtINFO indicates info level severity of a trace event.
-	CtINFO
+	// CtUnknown indicates unknown severity of a trace event.
+	CtUnknown Severity = iota
+	// CtInfo indicates info level severity of a trace event.
+	CtInfo
 	// CtWarning indicates warning level severity of a trace event.
 	CtWarning
 	// CtError indicates error level severity of a trace event.
@@ -687,12 +686,33 @@ const (
 type RefChannelType int
 
 const (
+	// RefUnknown indicates an unknown entity type, the zero value for this type.
+	RefUnknown RefChannelType = iota
 	// RefChannel indicates the referenced entity is a Channel.
-	RefChannel RefChannelType = iota
+	RefChannel
 	// RefSubChannel indicates the referenced entity is a SubChannel.
 	RefSubChannel
+	// RefServer indicates the referenced entity is a Server.
+	RefServer
+	// RefListenSocket indicates the referenced entity is a ListenSocket.
+	RefListenSocket
+	// RefNormalSocket indicates the referenced entity is a NormalSocket.
+	RefNormalSocket
 )
 
+var refChannelTypeToString = map[RefChannelType]string{
+	RefUnknown:      "Unknown",
+	RefChannel:      "Channel",
+	RefSubChannel:   "SubChannel",
+	RefServer:       "Server",
+	RefListenSocket: "ListenSocket",
+	RefNormalSocket: "NormalSocket",
+}
+
+func (r RefChannelType) String() string {
+	return refChannelTypeToString[r]
+}
+
 func (c *channelTrace) dumpData() *ChannelTrace {
 	c.mu.Lock()
 	ct := &ChannelTrace{EventNum: c.eventCount, CreationTime: c.createdTime}

vendor/google.golang.org/grpc/internal/channelz/types_linux.go

@@ -1,5 +1,3 @@
-// +build !appengine
-
 /*
  *
  * Copyright 2018 gRPC authors.

vendor/google.golang.org/grpc/internal/channelz/types_nonlinux.go

@@ -1,4 +1,5 @@
-// +build !linux appengine
+//go:build !linux
+// +build !linux
 
 /*
  *
@@ -22,8 +23,6 @@ package channelz
 
 import (
 	"sync"
-
-	"google.golang.org/grpc/grpclog"
 )
 
 var once sync.Once
@@ -39,6 +38,6 @@ type SocketOptionData struct {
 // Windows OS doesn't support Socket Option
 func (s *SocketOptionData) Getsockopt(fd uintptr) {
 	once.Do(func() {
-		grpclog.Warningln("Channelz: socket options are not supported on non-linux os and appengine.")
+		logger.Warning("Channelz: socket options are not supported on non-linux environments")
 	})
 }

vendor/google.golang.org/grpc/internal/channelz/util_linux.go

@@ -1,5 +1,3 @@
-// +build linux,!appengine
-
 /*
  *
  * Copyright 2018 gRPC authors.

vendor/google.golang.org/grpc/internal/channelz/util_nonlinux.go

@@ -1,4 +1,5 @@
-// +build !linux appengine
+//go:build !linux
+// +build !linux
 
 /*
  *

vendor/google.golang.org/grpc/internal/credentials/credentials.go

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2021 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package credentials
+
+import (
+	"context"
+)
+
+// requestInfoKey is a struct to be used as the key to store RequestInfo in a
+// context.
+type requestInfoKey struct{}
+
+// NewRequestInfoContext creates a context with ri.
+func NewRequestInfoContext(ctx context.Context, ri interface{}) context.Context {
+	return context.WithValue(ctx, requestInfoKey{}, ri)
+}
+
+// RequestInfoFromContext extracts the RequestInfo from ctx.
+func RequestInfoFromContext(ctx context.Context) interface{} {
+	return ctx.Value(requestInfoKey{})
+}
+
+// clientHandshakeInfoKey is a struct used as the key to store
+// ClientHandshakeInfo in a context.
+type clientHandshakeInfoKey struct{}
+
+// ClientHandshakeInfoFromContext extracts the ClientHandshakeInfo from ctx.
+func ClientHandshakeInfoFromContext(ctx context.Context) interface{} {
+	return ctx.Value(clientHandshakeInfoKey{})
+}
+
+// NewClientHandshakeInfoContext creates a context with chi.
+func NewClientHandshakeInfoContext(ctx context.Context, chi interface{}) context.Context {
+	return context.WithValue(ctx, clientHandshakeInfoKey{}, chi)
+}

vendor/google.golang.org/grpc/internal/credentials/spiffe.go

@@ -0,0 +1,75 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package credentials defines APIs for parsing SPIFFE ID.
+//
+// All APIs in this package are experimental.
+package credentials
+
+import (
+	"crypto/tls"
+	"crypto/x509"
+	"net/url"
+
+	"google.golang.org/grpc/grpclog"
+)
+
+var logger = grpclog.Component("credentials")
+
+// SPIFFEIDFromState parses the SPIFFE ID from State. If the SPIFFE ID format
+// is invalid, return nil with warning.
+func SPIFFEIDFromState(state tls.ConnectionState) *url.URL {
+	if len(state.PeerCertificates) == 0 || len(state.PeerCertificates[0].URIs) == 0 {
+		return nil
+	}
+	return SPIFFEIDFromCert(state.PeerCertificates[0])
+}
+
+// SPIFFEIDFromCert parses the SPIFFE ID from x509.Certificate. If the SPIFFE
+// ID format is invalid, return nil with warning.
+func SPIFFEIDFromCert(cert *x509.Certificate) *url.URL {
+	if cert == nil || cert.URIs == nil {
+		return nil
+	}
+	var spiffeID *url.URL
+	for _, uri := range cert.URIs {
+		if uri == nil || uri.Scheme != "spiffe" || uri.Opaque != "" || (uri.User != nil && uri.User.Username() != "") {
+			continue
+		}
+		// From this point, we assume the uri is intended for a SPIFFE ID.
+		if len(uri.String()) > 2048 {
+			logger.Warning("invalid SPIFFE ID: total ID length larger than 2048 bytes")
+			return nil
+		}
+		if len(uri.Host) == 0 || len(uri.Path) == 0 {
+			logger.Warning("invalid SPIFFE ID: domain or workload ID is empty")
+			return nil
+		}
+		if len(uri.Host) > 255 {
+			logger.Warning("invalid SPIFFE ID: domain length larger than 255 characters")
+			return nil
+		}
+		// A valid SPIFFE certificate can only have exactly one URI SAN field.
+		if len(cert.URIs) > 1 {
+			logger.Warning("invalid SPIFFE ID: multiple URI SANs")
+			return nil
+		}
+		spiffeID = uri
+	}
+	return spiffeID
+}

vendor/google.golang.org/grpc/internal/credentials/syscallconn.go

@@ -0,0 +1,58 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package credentials
+
+import (
+	"net"
+	"syscall"
+)
+
+type sysConn = syscall.Conn
+
+// syscallConn keeps reference of rawConn to support syscall.Conn for channelz.
+// SyscallConn() (the method in interface syscall.Conn) is explicitly
+// implemented on this type,
+//
+// Interface syscall.Conn is implemented by most net.Conn implementations (e.g.
+// TCPConn, UnixConn), but is not part of net.Conn interface. So wrapper conns
+// that embed net.Conn don't implement syscall.Conn. (Side note: tls.Conn
+// doesn't embed net.Conn, so even if syscall.Conn is part of net.Conn, it won't
+// help here).
+type syscallConn struct {
+	net.Conn
+	// sysConn is a type alias of syscall.Conn. It's necessary because the name
+	// `Conn` collides with `net.Conn`.
+	sysConn
+}
+
+// WrapSyscallConn tries to wrap rawConn and newConn into a net.Conn that
+// implements syscall.Conn. rawConn will be used to support syscall, and newConn
+// will be used for read/write.
+//
+// This function returns newConn if rawConn doesn't implement syscall.Conn.
+func WrapSyscallConn(rawConn, newConn net.Conn) net.Conn {
+	sysConn, ok := rawConn.(syscall.Conn)
+	if !ok {
+		return newConn
+	}
+	return &syscallConn{
+		Conn:    newConn,
+		sysConn: sysConn,
+	}
+}

vendor/google.golang.org/grpc/internal/credentials/util.go

@@ -0,0 +1,52 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package credentials
+
+import (
+	"crypto/tls"
+)
+
+const alpnProtoStrH2 = "h2"
+
+// AppendH2ToNextProtos appends h2 to next protos.
+func AppendH2ToNextProtos(ps []string) []string {
+	for _, p := range ps {
+		if p == alpnProtoStrH2 {
+			return ps
+		}
+	}
+	ret := make([]string, 0, len(ps)+1)
+	ret = append(ret, ps...)
+	return append(ret, alpnProtoStrH2)
+}
+
+// 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.
+//
+// TODO: inline this function if possible.
+func CloneTLSConfig(cfg *tls.Config) *tls.Config {
+	if cfg == nil {
+		return &tls.Config{}
+	}
+
+	return cfg.Clone()
+}

vendor/google.golang.org/grpc/internal/envconfig/envconfig.go

@@ -26,13 +26,10 @@ import (
 
 const (
 	prefix          = "GRPC_GO_"
-	retryStr        = prefix + "RETRY"
 	txtErrIgnoreStr = prefix + "IGNORE_TXT_ERRORS"
 )
 
 var (
-	// Retry is set if retry is explicitly enabled via "GRPC_GO_RETRY=on".
-	Retry = strings.EqualFold(os.Getenv(retryStr), "on")
 	// TXTErrIgnore is set if TXT errors should be ignored ("GRPC_GO_IGNORE_TXT_ERRORS" is not "false").
-	TXTErrIgnore = !strings.EqualFold(os.Getenv(retryStr), "false")
+	TXTErrIgnore = !strings.EqualFold(os.Getenv(txtErrIgnoreStr), "false")
 )

vendor/google.golang.org/grpc/internal/envconfig/xds.go

@@ -0,0 +1,101 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package envconfig
+
+import (
+	"os"
+	"strings"
+)
+
+const (
+	// XDSBootstrapFileNameEnv is the env variable to set bootstrap file name.
+	// Do not use this and read from env directly. Its value is read and kept in
+	// variable XDSBootstrapFileName.
+	//
+	// When both bootstrap FileName and FileContent are set, FileName is used.
+	XDSBootstrapFileNameEnv = "GRPC_XDS_BOOTSTRAP"
+	// XDSBootstrapFileContentEnv is the env variable to set bootstrap file
+	// content. Do not use this and read from env directly. Its value is read
+	// and kept in variable XDSBootstrapFileContent.
+	//
+	// When both bootstrap FileName and FileContent are set, FileName is used.
+	XDSBootstrapFileContentEnv = "GRPC_XDS_BOOTSTRAP_CONFIG"
+
+	ringHashSupportEnv           = "GRPC_XDS_EXPERIMENTAL_ENABLE_RING_HASH"
+	clientSideSecuritySupportEnv = "GRPC_XDS_EXPERIMENTAL_SECURITY_SUPPORT"
+	aggregateAndDNSSupportEnv    = "GRPC_XDS_EXPERIMENTAL_ENABLE_AGGREGATE_AND_LOGICAL_DNS_CLUSTER"
+	rbacSupportEnv               = "GRPC_XDS_EXPERIMENTAL_RBAC"
+	outlierDetectionSupportEnv   = "GRPC_EXPERIMENTAL_ENABLE_OUTLIER_DETECTION"
+	federationEnv                = "GRPC_EXPERIMENTAL_XDS_FEDERATION"
+	rlsInXDSEnv                  = "GRPC_EXPERIMENTAL_XDS_RLS_LB"
+
+	c2pResolverTestOnlyTrafficDirectorURIEnv = "GRPC_TEST_ONLY_GOOGLE_C2P_RESOLVER_TRAFFIC_DIRECTOR_URI"
+)
+
+var (
+	// XDSBootstrapFileName holds the name of the file which contains xDS
+	// bootstrap configuration. Users can specify the location of the bootstrap
+	// file by setting the environment variable "GRPC_XDS_BOOTSTRAP".
+	//
+	// When both bootstrap FileName and FileContent are set, FileName is used.
+	XDSBootstrapFileName = os.Getenv(XDSBootstrapFileNameEnv)
+	// XDSBootstrapFileContent holds the content of the xDS bootstrap
+	// configuration. Users can specify the bootstrap config by setting the
+	// environment variable "GRPC_XDS_BOOTSTRAP_CONFIG".
+	//
+	// When both bootstrap FileName and FileContent are set, FileName is used.
+	XDSBootstrapFileContent = os.Getenv(XDSBootstrapFileContentEnv)
+	// XDSRingHash indicates whether ring hash support is enabled, which can be
+	// disabled by setting the environment variable
+	// "GRPC_XDS_EXPERIMENTAL_ENABLE_RING_HASH" to "false".
+	XDSRingHash = !strings.EqualFold(os.Getenv(ringHashSupportEnv), "false")
+	// XDSClientSideSecurity is used to control processing of security
+	// configuration on the client-side.
+	//
+	// Note that there is no env var protection for the server-side because we
+	// have a brand new API on the server-side and users explicitly need to use
+	// the new API to get security integration on the server.
+	XDSClientSideSecurity = !strings.EqualFold(os.Getenv(clientSideSecuritySupportEnv), "false")
+	// XDSAggregateAndDNS indicates whether processing of aggregated cluster
+	// and DNS cluster is enabled, which can be enabled by setting the
+	// environment variable
+	// "GRPC_XDS_EXPERIMENTAL_ENABLE_AGGREGATE_AND_LOGICAL_DNS_CLUSTER" to
+	// "true".
+	XDSAggregateAndDNS = !strings.EqualFold(os.Getenv(aggregateAndDNSSupportEnv), "false")
+
+	// XDSRBAC indicates whether xDS configured RBAC HTTP Filter is enabled,
+	// which can be disabled by setting the environment variable
+	// "GRPC_XDS_EXPERIMENTAL_RBAC" to "false".
+	XDSRBAC = !strings.EqualFold(os.Getenv(rbacSupportEnv), "false")
+	// XDSOutlierDetection indicates whether outlier detection support is
+	// enabled, which can be enabled by setting the environment variable
+	// "GRPC_EXPERIMENTAL_ENABLE_OUTLIER_DETECTION" to "true".
+	XDSOutlierDetection = strings.EqualFold(os.Getenv(outlierDetectionSupportEnv), "true")
+	// XDSFederation indicates whether federation support is enabled.
+	XDSFederation = strings.EqualFold(os.Getenv(federationEnv), "true")
+
+	// XDSRLS indicates whether processing of Cluster Specifier plugins and
+	// support for the RLS CLuster Specifier is enabled, which can be enabled by
+	// setting the environment variable "GRPC_EXPERIMENTAL_XDS_RLS_LB" to
+	// "true".
+	XDSRLS = strings.EqualFold(os.Getenv(rlsInXDSEnv), "true")
+
+	// C2PResolverTestOnlyTrafficDirectorURI is the TD URI for testing.
+	C2PResolverTestOnlyTrafficDirectorURI = os.Getenv(c2pResolverTestOnlyTrafficDirectorURIEnv)
+)

vendor/google.golang.org/grpc/internal/grpclog/grpclog.go

@@ -0,0 +1,126 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package grpclog (internal) defines depth logging for grpc.
+package grpclog
+
+import (
+	"os"
+)
+
+// Logger is the logger used for the non-depth log functions.
+var Logger LoggerV2
+
+// DepthLogger is the logger used for the depth log functions.
+var DepthLogger DepthLoggerV2
+
+// InfoDepth logs to the INFO log at the specified depth.
+func InfoDepth(depth int, args ...interface{}) {
+	if DepthLogger != nil {
+		DepthLogger.InfoDepth(depth, args...)
+	} else {
+		Logger.Infoln(args...)
+	}
+}
+
+// WarningDepth logs to the WARNING log at the specified depth.
+func WarningDepth(depth int, args ...interface{}) {
+	if DepthLogger != nil {
+		DepthLogger.WarningDepth(depth, args...)
+	} else {
+		Logger.Warningln(args...)
+	}
+}
+
+// ErrorDepth logs to the ERROR log at the specified depth.
+func ErrorDepth(depth int, args ...interface{}) {
+	if DepthLogger != nil {
+		DepthLogger.ErrorDepth(depth, args...)
+	} else {
+		Logger.Errorln(args...)
+	}
+}
+
+// FatalDepth logs to the FATAL log at the specified depth.
+func FatalDepth(depth int, args ...interface{}) {
+	if DepthLogger != nil {
+		DepthLogger.FatalDepth(depth, args...)
+	} else {
+		Logger.Fatalln(args...)
+	}
+	os.Exit(1)
+}
+
+// LoggerV2 does underlying logging work for grpclog.
+// This is a copy of the LoggerV2 defined in the external grpclog package. It
+// is defined here to avoid a circular dependency.
+type LoggerV2 interface {
+	// Info logs to INFO log. Arguments are handled in the manner of fmt.Print.
+	Info(args ...interface{})
+	// Infoln logs to INFO log. Arguments are handled in the manner of fmt.Println.
+	Infoln(args ...interface{})
+	// Infof logs to INFO log. Arguments are handled in the manner of fmt.Printf.
+	Infof(format string, args ...interface{})
+	// Warning logs to WARNING log. Arguments are handled in the manner of fmt.Print.
+	Warning(args ...interface{})
+	// Warningln logs to WARNING log. Arguments are handled in the manner of fmt.Println.
+	Warningln(args ...interface{})
+	// Warningf logs to WARNING log. Arguments are handled in the manner of fmt.Printf.
+	Warningf(format string, args ...interface{})
+	// Error logs to ERROR log. Arguments are handled in the manner of fmt.Print.
+	Error(args ...interface{})
+	// Errorln logs to ERROR log. Arguments are handled in the manner of fmt.Println.
+	Errorln(args ...interface{})
+	// Errorf logs to ERROR log. Arguments are handled in the manner of fmt.Printf.
+	Errorf(format string, args ...interface{})
+	// Fatal logs to ERROR log. Arguments are handled in the manner of fmt.Print.
+	// gRPC ensures that all Fatal logs will exit with os.Exit(1).
+	// Implementations may also call os.Exit() with a non-zero exit code.
+	Fatal(args ...interface{})
+	// Fatalln logs to ERROR log. Arguments are handled in the manner of fmt.Println.
+	// gRPC ensures that all Fatal logs will exit with os.Exit(1).
+	// Implementations may also call os.Exit() with a non-zero exit code.
+	Fatalln(args ...interface{})
+	// Fatalf logs to ERROR log. Arguments are handled in the manner of fmt.Printf.
+	// gRPC ensures that all Fatal logs will exit with os.Exit(1).
+	// Implementations may also call os.Exit() with a non-zero exit code.
+	Fatalf(format string, args ...interface{})
+	// V reports whether verbosity level l is at least the requested verbose level.
+	V(l int) bool
+}
+
+// DepthLoggerV2 logs at a specified call frame. If a LoggerV2 also implements
+// DepthLoggerV2, the below functions will be called with the appropriate stack
+// depth set for trivial functions the logger may ignore.
+// This is a copy of the DepthLoggerV2 defined in the external grpclog package.
+// It is defined here to avoid a circular dependency.
+//
+// Experimental
+//
+// Notice: This type is EXPERIMENTAL and may be changed or removed in a
+// later release.
+type DepthLoggerV2 interface {
+	// InfoDepth logs to INFO log at the specified depth. Arguments are handled in the manner of fmt.Println.
+	InfoDepth(depth int, args ...interface{})
+	// WarningDepth logs to WARNING log at the specified depth. Arguments are handled in the manner of fmt.Println.
+	WarningDepth(depth int, args ...interface{})
+	// ErrorDepth logs to ERROR log at the specified depth. Arguments are handled in the manner of fmt.Println.
+	ErrorDepth(depth int, args ...interface{})
+	// FatalDepth logs to FATAL log at the specified depth. Arguments are handled in the manner of fmt.Println.
+	FatalDepth(depth int, args ...interface{})
+}

vendor/google.golang.org/grpc/internal/grpclog/prefixLogger.go

@@ -0,0 +1,81 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpclog
+
+import (
+	"fmt"
+)
+
+// PrefixLogger does logging with a prefix.
+//
+// Logging method on a nil logs without any prefix.
+type PrefixLogger struct {
+	logger DepthLoggerV2
+	prefix string
+}
+
+// Infof does info logging.
+func (pl *PrefixLogger) Infof(format string, args ...interface{}) {
+	if pl != nil {
+		// Handle nil, so the tests can pass in a nil logger.
+		format = pl.prefix + format
+		pl.logger.InfoDepth(1, fmt.Sprintf(format, args...))
+		return
+	}
+	InfoDepth(1, fmt.Sprintf(format, args...))
+}
+
+// Warningf does warning logging.
+func (pl *PrefixLogger) Warningf(format string, args ...interface{}) {
+	if pl != nil {
+		format = pl.prefix + format
+		pl.logger.WarningDepth(1, fmt.Sprintf(format, args...))
+		return
+	}
+	WarningDepth(1, fmt.Sprintf(format, args...))
+}
+
+// Errorf does error logging.
+func (pl *PrefixLogger) Errorf(format string, args ...interface{}) {
+	if pl != nil {
+		format = pl.prefix + format
+		pl.logger.ErrorDepth(1, fmt.Sprintf(format, args...))
+		return
+	}
+	ErrorDepth(1, fmt.Sprintf(format, args...))
+}
+
+// Debugf does info logging at verbose level 2.
+func (pl *PrefixLogger) Debugf(format string, args ...interface{}) {
+	if !Logger.V(2) {
+		return
+	}
+	if pl != nil {
+		// Handle nil, so the tests can pass in a nil logger.
+		format = pl.prefix + format
+		pl.logger.InfoDepth(1, fmt.Sprintf(format, args...))
+		return
+	}
+	InfoDepth(1, fmt.Sprintf(format, args...))
+}
+
+// NewPrefixLogger creates a prefix logger with the given prefix.
+func NewPrefixLogger(logger DepthLoggerV2, prefix string) *PrefixLogger {
+	return &PrefixLogger{logger: logger, prefix: prefix}
+}

vendor/google.golang.org/grpc/internal/grpcrand/grpcrand.go

@@ -31,26 +31,37 @@ var (
 	mu sync.Mutex
 )
 
+// Int implements rand.Int on the grpcrand global source.
+func Int() int {
+	mu.Lock()
+	defer mu.Unlock()
+	return r.Int()
+}
+
 // Int63n implements rand.Int63n on the grpcrand global source.
 func Int63n(n int64) int64 {
 	mu.Lock()
-	res := r.Int63n(n)
-	mu.Unlock()
-	return res
+	defer mu.Unlock()
+	return r.Int63n(n)
 }
 
 // Intn implements rand.Intn on the grpcrand global source.
 func Intn(n int) int {
 	mu.Lock()
-	res := r.Intn(n)
-	mu.Unlock()
-	return res
+	defer mu.Unlock()
+	return r.Intn(n)
 }
 
 // Float64 implements rand.Float64 on the grpcrand global source.
 func Float64() float64 {
 	mu.Lock()
-	res := r.Float64()
-	mu.Unlock()
-	return res
+	defer mu.Unlock()
+	return r.Float64()
+}
+
+// Uint64 implements rand.Uint64 on the grpcrand global source.
+func Uint64() uint64 {
+	mu.Lock()
+	defer mu.Unlock()
+	return r.Uint64()
 }

vendor/google.golang.org/grpc/internal/grpcutil/encode_duration.go

@@ -0,0 +1,63 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpcutil
+
+import (
+	"strconv"
+	"time"
+)
+
+const maxTimeoutValue int64 = 100000000 - 1
+
+// div does integer division and round-up the result. Note that this is
+// equivalent to (d+r-1)/r but has less chance to overflow.
+func div(d, r time.Duration) int64 {
+	if d%r > 0 {
+		return int64(d/r + 1)
+	}
+	return int64(d / r)
+}
+
+// EncodeDuration encodes the duration to the format grpc-timeout header
+// accepts.
+//
+// https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests
+func EncodeDuration(t time.Duration) string {
+	// TODO: This is simplistic and not bandwidth efficient. Improve it.
+	if t <= 0 {
+		return "0n"
+	}
+	if d := div(t, time.Nanosecond); d <= maxTimeoutValue {
+		return strconv.FormatInt(d, 10) + "n"
+	}
+	if d := div(t, time.Microsecond); d <= maxTimeoutValue {
+		return strconv.FormatInt(d, 10) + "u"
+	}
+	if d := div(t, time.Millisecond); d <= maxTimeoutValue {
+		return strconv.FormatInt(d, 10) + "m"
+	}
+	if d := div(t, time.Second); d <= maxTimeoutValue {
+		return strconv.FormatInt(d, 10) + "S"
+	}
+	if d := div(t, time.Minute); d <= maxTimeoutValue {
+		return strconv.FormatInt(d, 10) + "M"
+	}
+	// Note that maxTimeoutValue * time.Hour > MaxInt64.
+	return strconv.FormatInt(div(t, time.Hour), 10) + "H"
+}

vendor/google.golang.org/grpc/internal/grpcutil/grpcutil.go

@@ -1,8 +1,6 @@
-// +build go1.13
-
 /*
  *
- * Copyright 2019 gRPC authors.
+ * Copyright 2021 gRPC authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,16 +16,5 @@
  *
  */
 
-package dns
-
-import "net"
-
-func init() {
-	filterError = func(err error) error {
-		if dnsErr, ok := err.(*net.DNSError); ok && dnsErr.IsNotFound {
-			// The name does not exist; not an error.
-			return nil
-		}
-		return err
-	}
-}
+// Package grpcutil provides utility functions used across the gRPC codebase.
+package grpcutil

vendor/google.golang.org/grpc/internal/grpcutil/metadata.go

@@ -0,0 +1,40 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpcutil
+
+import (
+	"context"
+
+	"google.golang.org/grpc/metadata"
+)
+
+type mdExtraKey struct{}
+
+// WithExtraMetadata creates a new context with incoming md attached.
+func WithExtraMetadata(ctx context.Context, md metadata.MD) context.Context {
+	return context.WithValue(ctx, mdExtraKey{}, md)
+}
+
+// ExtraMetadata returns the incoming metadata in ctx if it exists.  The
+// returned MD should not be modified. Writing to it may cause races.
+// Modification should be made to copies of the returned MD.
+func ExtraMetadata(ctx context.Context) (md metadata.MD, ok bool) {
+	md, ok = ctx.Value(mdExtraKey{}).(metadata.MD)
+	return
+}

vendor/google.golang.org/grpc/internal/grpcutil/method.go

@@ -0,0 +1,84 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpcutil
+
+import (
+	"errors"
+	"strings"
+)
+
+// ParseMethod splits service and method from the input. It expects format
+// "/service/method".
+//
+func ParseMethod(methodName string) (service, method string, _ error) {
+	if !strings.HasPrefix(methodName, "/") {
+		return "", "", errors.New("invalid method name: should start with /")
+	}
+	methodName = methodName[1:]
+
+	pos := strings.LastIndex(methodName, "/")
+	if pos < 0 {
+		return "", "", errors.New("invalid method name: suffix /method is missing")
+	}
+	return methodName[:pos], methodName[pos+1:], nil
+}
+
+const baseContentType = "application/grpc"
+
+// ContentSubtype returns the content-subtype for the given content-type.  The
+// given content-type must be a valid content-type that starts with
+// "application/grpc". A content-subtype will follow "application/grpc" after a
+// "+" or ";". See
+// https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests for
+// more details.
+//
+// If contentType is not a valid content-type for gRPC, the boolean
+// will be false, otherwise true. If content-type == "application/grpc",
+// "application/grpc+", or "application/grpc;", the boolean will be true,
+// but no content-subtype will be returned.
+//
+// contentType is assumed to be lowercase already.
+func ContentSubtype(contentType string) (string, bool) {
+	if contentType == baseContentType {
+		return "", true
+	}
+	if !strings.HasPrefix(contentType, baseContentType) {
+		return "", false
+	}
+	// guaranteed since != baseContentType and has baseContentType prefix
+	switch contentType[len(baseContentType)] {
+	case '+', ';':
+		// this will return true for "application/grpc+" or "application/grpc;"
+		// which the previous validContentType function tested to be valid, so we
+		// just say that no content-subtype is specified in this case
+		return contentType[len(baseContentType)+1:], true
+	default:
+		return "", false
+	}
+}
+
+// ContentType builds full content type with the given sub-type.
+//
+// contentSubtype is assumed to be lowercase
+func ContentType(contentSubtype string) string {
+	if contentSubtype == "" {
+		return baseContentType
+	}
+	return baseContentType + "+" + contentSubtype
+}

vendor/google.golang.org/grpc/internal/grpcutil/regex.go

@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2017 gRPC authors.
+ * Copyright 2021 gRPC authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,29 +16,16 @@
  *
  */
 
-// This file contains wrappers for grpclog functions.
-// The transport package only logs to verbose level 2 by default.
+package grpcutil
 
-package transport
+import "regexp"
 
-import "google.golang.org/grpc/grpclog"
-
-const logLevel = 2
-
-func infof(format string, args ...interface{}) {
-	if grpclog.V(logLevel) {
-		grpclog.Infof(format, args...)
-	}
-}
-
-func warningf(format string, args ...interface{}) {
-	if grpclog.V(logLevel) {
-		grpclog.Warningf(format, args...)
-	}
-}
-
-func errorf(format string, args ...interface{}) {
-	if grpclog.V(logLevel) {
-		grpclog.Errorf(format, args...)
+// FullMatchWithRegex returns whether the full text matches the regex provided.
+func FullMatchWithRegex(re *regexp.Regexp, text string) bool {
+	if len(text) == 0 {
+		return re.MatchString(text)
 	}
+	re.Longest()
+	rem := re.FindString(text)
+	return len(rem) == len(text)
 }

vendor/google.golang.org/grpc/internal/internal.go

@@ -25,6 +25,7 @@ import (
 	"time"
 
 	"google.golang.org/grpc/connectivity"
+	"google.golang.org/grpc/serviceconfig"
 )
 
 var (
@@ -37,17 +38,101 @@ var (
 	// KeepaliveMinPingTime is the minimum ping interval.  This must be 10s by
 	// default, but tests may wish to set it lower for convenience.
 	KeepaliveMinPingTime = 10 * time.Second
-	// StatusRawProto is exported by status/status.go. This func returns a
-	// pointer to the wrapped Status proto for a given status.Status without a
-	// call to proto.Clone(). The returned Status proto should not be mutated by
-	// the caller.
-	StatusRawProto interface{} // func (*status.Status) *spb.Status
-	// NewRequestInfoContext creates a new context based on the argument context attaching
-	// the passed in RequestInfo to the new context.
-	NewRequestInfoContext interface{} // func(context.Context, credentials.RequestInfo) context.Context
-	// ParseServiceConfigForTesting is for creating a fake
-	// ClientConn for resolver testing only
-	ParseServiceConfigForTesting interface{} // func(string) *serviceconfig.ParseResult
+	// ParseServiceConfig parses a JSON representation of the service config.
+	ParseServiceConfig interface{} // func(string) *serviceconfig.ParseResult
+	// EqualServiceConfigForTesting is for testing service config generation and
+	// parsing. Both a and b should be returned by ParseServiceConfig.
+	// This function compares the config without rawJSON stripped, in case the
+	// there's difference in white space.
+	EqualServiceConfigForTesting func(a, b serviceconfig.Config) bool
+	// GetCertificateProviderBuilder returns the registered builder for the
+	// given name. This is set by package certprovider for use from xDS
+	// bootstrap code while parsing certificate provider configs in the
+	// bootstrap file.
+	GetCertificateProviderBuilder interface{} // func(string) certprovider.Builder
+	// GetXDSHandshakeInfoForTesting returns a pointer to the xds.HandshakeInfo
+	// stored in the passed in attributes. This is set by
+	// credentials/xds/xds.go.
+	GetXDSHandshakeInfoForTesting interface{} // func (*attributes.Attributes) *xds.HandshakeInfo
+	// GetServerCredentials returns the transport credentials configured on a
+	// gRPC server. An xDS-enabled server needs to know what type of credentials
+	// is configured on the underlying gRPC server. This is set by server.go.
+	GetServerCredentials interface{} // func (*grpc.Server) credentials.TransportCredentials
+	// DrainServerTransports initiates a graceful close of existing connections
+	// on a gRPC server accepted on the provided listener address. An
+	// xDS-enabled server invokes this method on a grpc.Server when a particular
+	// listener moves to "not-serving" mode.
+	DrainServerTransports interface{} // func(*grpc.Server, string)
+	// AddExtraServerOptions adds an array of ServerOption that will be
+	// effective globally for newly created servers. The priority will be: 1.
+	// user-provided; 2. this method; 3. default values.
+	AddExtraServerOptions interface{} // func(opt ...ServerOption)
+	// ClearExtraServerOptions clears the array of extra ServerOption. This
+	// method is useful in testing and benchmarking.
+	ClearExtraServerOptions func()
+	// AddExtraDialOptions adds an array of DialOption that will be effective
+	// globally for newly created client channels. The priority will be: 1.
+	// user-provided; 2. this method; 3. default values.
+	AddExtraDialOptions interface{} // func(opt ...DialOption)
+	// ClearExtraDialOptions clears the array of extra DialOption. This
+	// method is useful in testing and benchmarking.
+	ClearExtraDialOptions func()
+
+	// NewXDSResolverWithConfigForTesting creates a new xds resolver builder using
+	// the provided xds bootstrap config instead of the global configuration from
+	// the supported environment variables.  The resolver.Builder is meant to be
+	// used in conjunction with the grpc.WithResolvers DialOption.
+	//
+	// Testing Only
+	//
+	// This function should ONLY be used for testing and may not work with some
+	// other features, including the CSDS service.
+	NewXDSResolverWithConfigForTesting interface{} // func([]byte) (resolver.Builder, error)
+
+	// RegisterRLSClusterSpecifierPluginForTesting registers the RLS Cluster
+	// Specifier Plugin for testing purposes, regardless of the XDSRLS environment
+	// variable.
+	//
+	// TODO: Remove this function once the RLS env var is removed.
+	RegisterRLSClusterSpecifierPluginForTesting func()
+
+	// UnregisterRLSClusterSpecifierPluginForTesting unregisters the RLS Cluster
+	// Specifier Plugin for testing purposes. This is needed because there is no way
+	// to unregister the RLS Cluster Specifier Plugin after registering it solely
+	// for testing purposes using RegisterRLSClusterSpecifierPluginForTesting().
+	//
+	// TODO: Remove this function once the RLS env var is removed.
+	UnregisterRLSClusterSpecifierPluginForTesting func()
+
+	// RegisterRBACHTTPFilterForTesting registers the RBAC HTTP Filter for testing
+	// purposes, regardless of the RBAC environment variable.
+	//
+	// TODO: Remove this function once the RBAC env var is removed.
+	RegisterRBACHTTPFilterForTesting func()
+
+	// UnregisterRBACHTTPFilterForTesting unregisters the RBAC HTTP Filter for
+	// testing purposes. This is needed because there is no way to unregister the
+	// HTTP Filter after registering it solely for testing purposes using
+	// RegisterRBACHTTPFilterForTesting().
+	//
+	// TODO: Remove this function once the RBAC env var is removed.
+	UnregisterRBACHTTPFilterForTesting func()
+
+	// RegisterOutlierDetectionBalancerForTesting registers the Outlier
+	// Detection Balancer for testing purposes, regardless of the Outlier
+	// Detection environment variable.
+	//
+	// TODO: Remove this function once the Outlier Detection env var is removed.
+	RegisterOutlierDetectionBalancerForTesting func()
+
+	// UnregisterOutlierDetectionBalancerForTesting unregisters the Outlier
+	// Detection Balancer for testing purposes. This is needed because there is
+	// no way to unregister the Outlier Detection Balancer after registering it
+	// solely for testing purposes using
+	// RegisterOutlierDetectionBalancerForTesting().
+	//
+	// TODO: Remove this function once the Outlier Detection env var is removed.
+	UnregisterOutlierDetectionBalancerForTesting func()
 )
 
 // HealthChecker defines the signature of the client-side LB channel health checking function.
@@ -70,3 +155,9 @@ const (
 	// that supports backend returned by grpclb balancer.
 	CredsBundleModeBackendFromBalancer = "backend-from-balancer"
 )
+
+// RLSLoadBalancingPolicyName is the name of the RLS LB policy.
+//
+// It currently has an experimental suffix which would be removed once
+// end-to-end testing of the policy is completed.
+const RLSLoadBalancingPolicyName = "rls_experimental"

vendor/google.golang.org/grpc/internal/metadata/metadata.go

@@ -0,0 +1,120 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package metadata contains functions to set and get metadata from addresses.
+//
+// This package is experimental.
+package metadata
+
+import (
+	"fmt"
+	"strings"
+
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/resolver"
+)
+
+type mdKeyType string
+
+const mdKey = mdKeyType("grpc.internal.address.metadata")
+
+type mdValue metadata.MD
+
+func (m mdValue) Equal(o interface{}) bool {
+	om, ok := o.(mdValue)
+	if !ok {
+		return false
+	}
+	if len(m) != len(om) {
+		return false
+	}
+	for k, v := range m {
+		ov := om[k]
+		if len(ov) != len(v) {
+			return false
+		}
+		for i, ve := range v {
+			if ov[i] != ve {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// Get returns the metadata of addr.
+func Get(addr resolver.Address) metadata.MD {
+	attrs := addr.Attributes
+	if attrs == nil {
+		return nil
+	}
+	md, _ := attrs.Value(mdKey).(mdValue)
+	return metadata.MD(md)
+}
+
+// Set sets (overrides) the metadata in addr.
+//
+// When a SubConn is created with this address, the RPCs sent on it will all
+// have this metadata.
+func Set(addr resolver.Address, md metadata.MD) resolver.Address {
+	addr.Attributes = addr.Attributes.WithValue(mdKey, mdValue(md))
+	return addr
+}
+
+// Validate returns an error if the input md contains invalid keys or values.
+//
+// If the header is not a pseudo-header, the following items are checked:
+// - header names must contain one or more characters from this set [0-9 a-z _ - .].
+// - if the header-name ends with a "-bin" suffix, no validation of the header value is performed.
+// - otherwise, the header value must contain one or more characters from the set [%x20-%x7E].
+func Validate(md metadata.MD) error {
+	for k, vals := range md {
+		// pseudo-header will be ignored
+		if k[0] == ':' {
+			continue
+		}
+		// check key, for i that saving a conversion if not using for range
+		for i := 0; i < len(k); i++ {
+			r := k[i]
+			if !(r >= 'a' && r <= 'z') && !(r >= '0' && r <= '9') && r != '.' && r != '-' && r != '_' {
+				return fmt.Errorf("header key %q contains illegal characters not in [0-9a-z-_.]", k)
+			}
+		}
+		if strings.HasSuffix(k, "-bin") {
+			continue
+		}
+		// check value
+		for _, val := range vals {
+			if hasNotPrintable(val) {
+				return fmt.Errorf("header key %q contains value with non-printable ASCII characters", k)
+			}
+		}
+	}
+	return nil
+}
+
+// hasNotPrintable return true if msg contains any characters which are not in %x20-%x7E
+func hasNotPrintable(msg string) bool {
+	// for i that saving a conversion if not using for range
+	for i := 0; i < len(msg); i++ {
+		if msg[i] < 0x20 || msg[i] > 0x7E {
+			return true
+		}
+	}
+	return false
+}

vendor/google.golang.org/grpc/internal/pretty/pretty.go

@@ -0,0 +1,82 @@
+/*
+ *
+ * Copyright 2021 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package pretty defines helper functions to pretty-print structs for logging.
+package pretty
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+
+	"github.com/golang/protobuf/jsonpb"
+	protov1 "github.com/golang/protobuf/proto"
+	"google.golang.org/protobuf/encoding/protojson"
+	protov2 "google.golang.org/protobuf/proto"
+)
+
+const jsonIndent = "  "
+
+// ToJSON marshals the input into a json string.
+//
+// If marshal fails, it falls back to fmt.Sprintf("%+v").
+func ToJSON(e interface{}) string {
+	switch ee := e.(type) {
+	case protov1.Message:
+		mm := jsonpb.Marshaler{Indent: jsonIndent}
+		ret, err := mm.MarshalToString(ee)
+		if err != nil {
+			// This may fail for proto.Anys, e.g. for xDS v2, LDS, the v2
+			// messages are not imported, and this will fail because the message
+			// is not found.
+			return fmt.Sprintf("%+v", ee)
+		}
+		return ret
+	case protov2.Message:
+		mm := protojson.MarshalOptions{
+			Multiline: true,
+			Indent:    jsonIndent,
+		}
+		ret, err := mm.Marshal(ee)
+		if err != nil {
+			// This may fail for proto.Anys, e.g. for xDS v2, LDS, the v2
+			// messages are not imported, and this will fail because the message
+			// is not found.
+			return fmt.Sprintf("%+v", ee)
+		}
+		return string(ret)
+	default:
+		ret, err := json.MarshalIndent(ee, "", jsonIndent)
+		if err != nil {
+			return fmt.Sprintf("%+v", ee)
+		}
+		return string(ret)
+	}
+}
+
+// FormatJSON formats the input json bytes with indentation.
+//
+// If Indent fails, it returns the unchanged input as string.
+func FormatJSON(b []byte) string {
+	var out bytes.Buffer
+	err := json.Indent(&out, b, "", jsonIndent)
+	if err != nil {
+		return string(b)
+	}
+	return out.String()
+}

vendor/google.golang.org/grpc/internal/resolver/config_selector.go

@@ -0,0 +1,167 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package resolver provides internal resolver-related functionality.
+package resolver
+
+import (
+	"context"
+	"sync"
+
+	"google.golang.org/grpc/internal/serviceconfig"
+	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/resolver"
+)
+
+// ConfigSelector controls what configuration to use for every RPC.
+type ConfigSelector interface {
+	// Selects the configuration for the RPC, or terminates it using the error.
+	// This error will be converted by the gRPC library to a status error with
+	// code UNKNOWN if it is not returned as a status error.
+	SelectConfig(RPCInfo) (*RPCConfig, error)
+}
+
+// RPCInfo contains RPC information needed by a ConfigSelector.
+type RPCInfo struct {
+	// Context is the user's context for the RPC and contains headers and
+	// application timeout.  It is passed for interception purposes and for
+	// efficiency reasons.  SelectConfig should not be blocking.
+	Context context.Context
+	Method  string // i.e. "/Service/Method"
+}
+
+// RPCConfig describes the configuration to use for each RPC.
+type RPCConfig struct {
+	// The context to use for the remainder of the RPC; can pass info to LB
+	// policy or affect timeout or metadata.
+	Context      context.Context
+	MethodConfig serviceconfig.MethodConfig // configuration to use for this RPC
+	OnCommitted  func()                     // Called when the RPC has been committed (retries no longer possible)
+	Interceptor  ClientInterceptor
+}
+
+// ClientStream is the same as grpc.ClientStream, but defined here for circular
+// dependency reasons.
+type ClientStream interface {
+	// Header returns the header metadata received from the server if there
+	// is any. It blocks if the metadata is not ready to read.
+	Header() (metadata.MD, error)
+	// Trailer returns the trailer metadata from the server, if there is any.
+	// It must only be called after stream.CloseAndRecv has returned, or
+	// stream.Recv has returned a non-nil error (including io.EOF).
+	Trailer() metadata.MD
+	// CloseSend closes the send direction of the stream. It closes the stream
+	// when non-nil error is met. It is also not safe to call CloseSend
+	// concurrently with SendMsg.
+	CloseSend() error
+	// Context returns the context for this stream.
+	//
+	// It should not be called until after Header or RecvMsg has returned. Once
+	// called, subsequent client-side retries are disabled.
+	Context() context.Context
+	// SendMsg is generally called by generated code. On error, SendMsg aborts
+	// the stream. If the error was generated by the client, the status is
+	// returned directly; otherwise, io.EOF is returned and the status of
+	// the stream may be discovered using RecvMsg.
+	//
+	// SendMsg blocks until:
+	//   - There is sufficient flow control to schedule m with the transport, or
+	//   - The stream is done, or
+	//   - The stream breaks.
+	//
+	// SendMsg does not wait until the message is received by the server. An
+	// untimely stream closure may result in lost messages. To ensure delivery,
+	// users should ensure the RPC completed successfully using RecvMsg.
+	//
+	// It is safe to have a goroutine calling SendMsg and another goroutine
+	// calling RecvMsg on the same stream at the same time, but it is not safe
+	// to call SendMsg on the same stream in different goroutines. It is also
+	// not safe to call CloseSend concurrently with SendMsg.
+	SendMsg(m interface{}) error
+	// RecvMsg blocks until it receives a message into m or the stream is
+	// done. It returns io.EOF when the stream completes successfully. On
+	// any other error, the stream is aborted and the error contains the RPC
+	// status.
+	//
+	// It is safe to have a goroutine calling SendMsg and another goroutine
+	// calling RecvMsg on the same stream at the same time, but it is not
+	// safe to call RecvMsg on the same stream in different goroutines.
+	RecvMsg(m interface{}) error
+}
+
+// ClientInterceptor is an interceptor for gRPC client streams.
+type ClientInterceptor interface {
+	// NewStream produces a ClientStream for an RPC which may optionally use
+	// the provided function to produce a stream for delegation.  Note:
+	// RPCInfo.Context should not be used (will be nil).
+	//
+	// done is invoked when the RPC is finished using its connection, or could
+	// not be assigned a connection.  RPC operations may still occur on
+	// ClientStream after done is called, since the interceptor is invoked by
+	// application-layer operations.  done must never be nil when called.
+	NewStream(ctx context.Context, ri RPCInfo, done func(), newStream func(ctx context.Context, done func()) (ClientStream, error)) (ClientStream, error)
+}
+
+// ServerInterceptor is an interceptor for incoming RPC's on gRPC server side.
+type ServerInterceptor interface {
+	// AllowRPC checks if an incoming RPC is allowed to proceed based on
+	// information about connection RPC was received on, and HTTP Headers. This
+	// information will be piped into context.
+	AllowRPC(ctx context.Context) error // TODO: Make this a real interceptor for filters such as rate limiting.
+}
+
+type csKeyType string
+
+const csKey = csKeyType("grpc.internal.resolver.configSelector")
+
+// SetConfigSelector sets the config selector in state and returns the new
+// state.
+func SetConfigSelector(state resolver.State, cs ConfigSelector) resolver.State {
+	state.Attributes = state.Attributes.WithValue(csKey, cs)
+	return state
+}
+
+// GetConfigSelector retrieves the config selector from state, if present, and
+// returns it or nil if absent.
+func GetConfigSelector(state resolver.State) ConfigSelector {
+	cs, _ := state.Attributes.Value(csKey).(ConfigSelector)
+	return cs
+}
+
+// SafeConfigSelector allows for safe switching of ConfigSelector
+// implementations such that previous values are guaranteed to not be in use
+// when UpdateConfigSelector returns.
+type SafeConfigSelector struct {
+	mu sync.RWMutex
+	cs ConfigSelector
+}
+
+// UpdateConfigSelector swaps to the provided ConfigSelector and blocks until
+// all uses of the previous ConfigSelector have completed.
+func (scs *SafeConfigSelector) UpdateConfigSelector(cs ConfigSelector) {
+	scs.mu.Lock()
+	defer scs.mu.Unlock()
+	scs.cs = cs
+}
+
+// SelectConfig defers to the current ConfigSelector in scs.
+func (scs *SafeConfigSelector) SelectConfig(r RPCInfo) (*RPCConfig, error) {
+	scs.mu.RLock()
+	defer scs.mu.RUnlock()
+	return scs.cs.SelectConfig(r)
+}

vendor/google.golang.org/grpc/internal/resolver/dns/dns_resolver.go

@@ -32,7 +32,9 @@ import (
 	"sync"
 	"time"
 
+	grpclbstate "google.golang.org/grpc/balancer/grpclb/state"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal/backoff"
 	"google.golang.org/grpc/internal/envconfig"
 	"google.golang.org/grpc/internal/grpcrand"
 	"google.golang.org/grpc/resolver"
@@ -43,6 +45,15 @@ import (
 // addresses from SRV records.  Must not be changed after init time.
 var EnableSRVLookups = false
 
+var logger = grpclog.Component("dns")
+
+// Globals to stub out in tests. TODO: Perhaps these two can be combined into a
+// single variable for testing the resolver?
+var (
+	newTimer           = time.NewTimer
+	newTimerDNSResRate = time.NewTimer
+)
+
 func init() {
 	resolver.Register(NewBuilder())
 }
@@ -140,7 +151,6 @@ func (b *dnsBuilder) Build(target resolver.Target, cc resolver.ClientConn, opts
 
 	d.wg.Add(1)
 	go d.watcher()
-	d.ResolveNow(resolver.ResolveNowOptions{})
 	return d, nil
 }
 
@@ -198,28 +208,38 @@ func (d *dnsResolver) Close() {
 
 func (d *dnsResolver) watcher() {
 	defer d.wg.Done()
+	backoffIndex := 1
 	for {
-		select {
-		case <-d.ctx.Done():
-			return
-		case <-d.rn:
-		}
-
 		state, err := d.lookup()
 		if err != nil {
+			// Report error to the underlying grpc.ClientConn.
 			d.cc.ReportError(err)
 		} else {
-			d.cc.UpdateState(*state)
+			err = d.cc.UpdateState(*state)
 		}
 
-		// Sleep to prevent excessive re-resolutions. Incoming resolution requests
-		// will be queued in d.rn.
-		t := time.NewTimer(minDNSResRate)
+		var timer *time.Timer
+		if err == nil {
+			// Success resolving, wait for the next ResolveNow. However, also wait 30 seconds at the very least
+			// to prevent constantly re-resolving.
+			backoffIndex = 1
+			timer = newTimerDNSResRate(minDNSResRate)
+			select {
+			case <-d.ctx.Done():
+				timer.Stop()
+				return
+			case <-d.rn:
+			}
+		} else {
+			// Poll on an error found in DNS Resolver or an error received from ClientConn.
+			timer = newTimer(backoff.DefaultExponential.Backoff(backoffIndex))
+			backoffIndex++
+		}
 		select {
-		case <-t.C:
 		case <-d.ctx.Done():
-			t.Stop()
+			timer.Stop()
 			return
+		case <-timer.C:
 		}
 	}
 }
@@ -251,27 +271,22 @@ func (d *dnsResolver) lookupSRV() ([]resolver.Address, error) {
 				return nil, fmt.Errorf("dns: error parsing A record IP address %v", a)
 			}
 			addr := ip + ":" + strconv.Itoa(int(s.Port))
-			newAddrs = append(newAddrs, resolver.Address{Addr: addr, Type: resolver.GRPCLB, ServerName: s.Target})
+			newAddrs = append(newAddrs, resolver.Address{Addr: addr, ServerName: s.Target})
 		}
 	}
 	return newAddrs, nil
 }
 
-var filterError = func(err error) error {
+func handleDNSError(err error, lookupType string) error {
 	if dnsErr, ok := err.(*net.DNSError); ok && !dnsErr.IsTimeout && !dnsErr.IsTemporary {
 		// Timeouts and temporary errors should be communicated to gRPC to
 		// attempt another DNS query (with backoff).  Other errors should be
 		// suppressed (they may represent the absence of a TXT record).
 		return nil
 	}
-	return err
-}
-
-func handleDNSError(err error, lookupType string) error {
-	err = filterError(err)
 	if err != nil {
 		err = fmt.Errorf("dns: %v record lookup error: %v", lookupType, err)
-		grpclog.Infoln(err)
+		logger.Info(err)
 	}
 	return err
 }
@@ -294,7 +309,7 @@ func (d *dnsResolver) lookupTXT() *serviceconfig.ParseResult {
 
 	// TXT record must have "grpc_config=" attribute in order to be used as service config.
 	if !strings.HasPrefix(res, txtAttribute) {
-		grpclog.Warningf("dns: TXT record %v missing %v attribute", res, txtAttribute)
+		logger.Warningf("dns: TXT record %v missing %v attribute", res, txtAttribute)
 		// This is not an error; it is the equivalent of not having a service config.
 		return nil
 	}
@@ -303,12 +318,12 @@ func (d *dnsResolver) lookupTXT() *serviceconfig.ParseResult {
 }
 
 func (d *dnsResolver) lookupHost() ([]resolver.Address, error) {
-	var newAddrs []resolver.Address
 	addrs, err := d.resolver.LookupHost(d.ctx, d.host)
 	if err != nil {
 		err = handleDNSError(err, "A")
 		return nil, err
 	}
+	newAddrs := make([]resolver.Address, 0, len(addrs))
 	for _, a := range addrs {
 		ip, ok := formatIP(a)
 		if !ok {
@@ -326,13 +341,15 @@ func (d *dnsResolver) lookup() (*resolver.State, error) {
 	if hostErr != nil && (srvErr != nil || len(srv) == 0) {
 		return nil, hostErr
 	}
-	state := &resolver.State{
-		Addresses: append(addrs, srv...),
+
+	state := resolver.State{Addresses: addrs}
+	if len(srv) > 0 {
+		state = grpclbstate.Set(state, &grpclbstate.State{BalancerAddresses: srv})
 	}
 	if !d.disableServiceConfig {
 		state.ServiceConfig = d.lookupTXT()
 	}
-	return state, nil
+	return &state, nil
 }
 
 // formatIP returns ok = false if addr is not a valid textual representation of an IP address.
@@ -418,12 +435,12 @@ func canaryingSC(js string) string {
 	var rcs []rawChoice
 	err := json.Unmarshal([]byte(js), &rcs)
 	if err != nil {
-		grpclog.Warningf("dns: error parsing service config json: %v", err)
+		logger.Warningf("dns: error parsing service config json: %v", err)
 		return ""
 	}
 	cliHostname, err := os.Hostname()
 	if err != nil {
-		grpclog.Warningf("dns: error getting client hostname: %v", err)
+		logger.Warningf("dns: error getting client hostname: %v", err)
 		return ""
 	}
 	var sc string

vendor/google.golang.org/grpc/internal/resolver/unix/unix.go

@@ -0,0 +1,73 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package unix implements a resolver for unix targets.
+package unix
+
+import (
+	"fmt"
+
+	"google.golang.org/grpc/internal/transport/networktype"
+	"google.golang.org/grpc/resolver"
+)
+
+const unixScheme = "unix"
+const unixAbstractScheme = "unix-abstract"
+
+type builder struct {
+	scheme string
+}
+
+func (b *builder) Build(target resolver.Target, cc resolver.ClientConn, _ resolver.BuildOptions) (resolver.Resolver, error) {
+	if target.Authority != "" {
+		return nil, fmt.Errorf("invalid (non-empty) authority: %v", target.Authority)
+	}
+
+	// gRPC was parsing the dial target manually before PR #4817, and we
+	// switched to using url.Parse() in that PR. To avoid breaking existing
+	// resolver implementations we ended up stripping the leading "/" from the
+	// endpoint. This obviously does not work for the "unix" scheme. Hence we
+	// end up using the parsed URL instead.
+	endpoint := target.URL.Path
+	if endpoint == "" {
+		endpoint = target.URL.Opaque
+	}
+	addr := resolver.Address{Addr: endpoint}
+	if b.scheme == unixAbstractScheme {
+		// prepend "\x00" to address for unix-abstract
+		addr.Addr = "\x00" + addr.Addr
+	}
+	cc.UpdateState(resolver.State{Addresses: []resolver.Address{networktype.Set(addr, "unix")}})
+	return &nopResolver{}, nil
+}
+
+func (b *builder) Scheme() string {
+	return b.scheme
+}
+
+type nopResolver struct {
+}
+
+func (*nopResolver) ResolveNow(resolver.ResolveNowOptions) {}
+
+func (*nopResolver) Close() {}
+
+func init() {
+	resolver.Register(&builder{scheme: unixScheme})
+	resolver.Register(&builder{scheme: unixAbstractScheme})
+}

vendor/google.golang.org/grpc/internal/serviceconfig/serviceconfig.go

@@ -0,0 +1,180 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package serviceconfig contains utility functions to parse service config.
+package serviceconfig
+
+import (
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"google.golang.org/grpc/balancer"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/grpclog"
+	externalserviceconfig "google.golang.org/grpc/serviceconfig"
+)
+
+var logger = grpclog.Component("core")
+
+// BalancerConfig wraps the name and config associated with one load balancing
+// policy. It corresponds to a single entry of the loadBalancingConfig field
+// from ServiceConfig.
+//
+// It implements the json.Unmarshaler interface.
+//
+// https://github.com/grpc/grpc-proto/blob/54713b1e8bc6ed2d4f25fb4dff527842150b91b2/grpc/service_config/service_config.proto#L247
+type BalancerConfig struct {
+	Name   string
+	Config externalserviceconfig.LoadBalancingConfig
+}
+
+type intermediateBalancerConfig []map[string]json.RawMessage
+
+// MarshalJSON implements the json.Marshaler interface.
+//
+// It marshals the balancer and config into a length-1 slice
+// ([]map[string]config).
+func (bc *BalancerConfig) MarshalJSON() ([]byte, error) {
+	if bc.Config == nil {
+		// If config is nil, return empty config `{}`.
+		return []byte(fmt.Sprintf(`[{%q: %v}]`, bc.Name, "{}")), nil
+	}
+	c, err := json.Marshal(bc.Config)
+	if err != nil {
+		return nil, err
+	}
+	return []byte(fmt.Sprintf(`[{%q: %s}]`, bc.Name, c)), nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+//
+// ServiceConfig contains a list of loadBalancingConfigs, each with a name and
+// config. This method iterates through that list in order, and stops at the
+// first policy that is supported.
+// - If the config for the first supported policy is invalid, the whole service
+//   config is invalid.
+// - If the list doesn't contain any supported policy, the whole service config
+//   is invalid.
+func (bc *BalancerConfig) UnmarshalJSON(b []byte) error {
+	var ir intermediateBalancerConfig
+	err := json.Unmarshal(b, &ir)
+	if err != nil {
+		return err
+	}
+
+	var names []string
+	for i, lbcfg := range ir {
+		if len(lbcfg) != 1 {
+			return fmt.Errorf("invalid loadBalancingConfig: entry %v does not contain exactly 1 policy/config pair: %q", i, lbcfg)
+		}
+
+		var (
+			name    string
+			jsonCfg json.RawMessage
+		)
+		// Get the key:value pair from the map. We have already made sure that
+		// the map contains a single entry.
+		for name, jsonCfg = range lbcfg {
+		}
+
+		names = append(names, name)
+		builder := balancer.Get(name)
+		if builder == nil {
+			// If the balancer is not registered, move on to the next config.
+			// This is not an error.
+			continue
+		}
+		bc.Name = name
+
+		parser, ok := builder.(balancer.ConfigParser)
+		if !ok {
+			if string(jsonCfg) != "{}" {
+				logger.Warningf("non-empty balancer configuration %q, but balancer does not implement ParseConfig", string(jsonCfg))
+			}
+			// Stop at this, though the builder doesn't support parsing config.
+			return nil
+		}
+
+		cfg, err := parser.ParseConfig(jsonCfg)
+		if err != nil {
+			return fmt.Errorf("error parsing loadBalancingConfig for policy %q: %v", name, err)
+		}
+		bc.Config = cfg
+		return nil
+	}
+	// This is reached when the for loop iterates over all entries, but didn't
+	// return. This means we had a loadBalancingConfig slice but did not
+	// encounter a registered policy. The config is considered invalid in this
+	// case.
+	return fmt.Errorf("invalid loadBalancingConfig: no supported policies found in %v", names)
+}
+
+// MethodConfig defines the configuration recommended by the service providers for a
+// particular method.
+type MethodConfig struct {
+	// WaitForReady indicates whether RPCs sent to this method should wait until
+	// the connection is ready by default (!failfast). The value specified via the
+	// gRPC client API will override the value set here.
+	WaitForReady *bool
+	// Timeout is the default timeout for RPCs sent to this method. The actual
+	// deadline used will be the minimum of the value specified here and the value
+	// set by the application via the gRPC client API.  If either one is not set,
+	// then the other will be used.  If neither is set, then the RPC has no deadline.
+	Timeout *time.Duration
+	// MaxReqSize is the maximum allowed payload size for an individual request in a
+	// stream (client->server) in bytes. The size which is measured is the serialized
+	// payload after per-message compression (but before stream compression) in bytes.
+	// The actual value used is the minimum of the value specified here and the value set
+	// by the application via the gRPC client API. If either one is not set, then the other
+	// will be used.  If neither is set, then the built-in default is used.
+	MaxReqSize *int
+	// MaxRespSize is the maximum allowed payload size for an individual response in a
+	// stream (server->client) in bytes.
+	MaxRespSize *int
+	// RetryPolicy configures retry options for the method.
+	RetryPolicy *RetryPolicy
+}
+
+// RetryPolicy defines the go-native version of the retry policy defined by the
+// service config here:
+// https://github.com/grpc/proposal/blob/master/A6-client-retries.md#integration-with-service-config
+type RetryPolicy struct {
+	// MaxAttempts is the maximum number of attempts, including the original RPC.
+	//
+	// This field is required and must be two or greater.
+	MaxAttempts int
+
+	// Exponential backoff parameters. The initial retry attempt will occur at
+	// random(0, initialBackoff). In general, the nth attempt will occur at
+	// random(0,
+	//   min(initialBackoff*backoffMultiplier**(n-1), maxBackoff)).
+	//
+	// These fields are required and must be greater than zero.
+	InitialBackoff    time.Duration
+	MaxBackoff        time.Duration
+	BackoffMultiplier float64
+
+	// The set of status codes which may be retried.
+	//
+	// Status codes are specified as strings, e.g., "UNAVAILABLE".
+	//
+	// This field is required and must be non-empty.
+	// Note: a set is used to store this for easy lookup.
+	RetryableStatusCodes map[codes.Code]bool
+}

vendor/google.golang.org/grpc/internal/status/status.go

@@ -0,0 +1,166 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package 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 (
+	"errors"
+	"fmt"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/golang/protobuf/ptypes"
+	spb "google.golang.org/genproto/googleapis/rpc/status"
+	"google.golang.org/grpc/codes"
+)
+
+// 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
+}
+
+// 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...))
+}
+
+// FromProto returns a Status representing s.
+func FromProto(s *spb.Status) *Status {
+	return &Status{s: proto.Clone(s).(*spb.Status)}
+}
+
+// Err returns an error representing c and msg.  If c is OK, returns nil.
+func Err(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 Err(c, fmt.Sprintf(format, a...))
+}
+
+// Code returns the status code contained in s.
+func (s *Status) Code() codes.Code {
+	if s == nil || s.s == nil {
+		return codes.OK
+	}
+	return codes.Code(s.s.Code)
+}
+
+// Message returns the message contained in s.
+func (s *Status) Message() string {
+	if s == nil || s.s == nil {
+		return ""
+	}
+	return s.s.Message
+}
+
+// Proto returns s's status as an spb.Status proto message.
+func (s *Status) Proto() *spb.Status {
+	if s == nil {
+		return nil
+	}
+	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 &Error{s: s}
+}
+
+// WithDetails returns a new status with the provided details messages appended to the status.
+// If any errors are encountered, it returns nil and the first error encountered.
+func (s *Status) WithDetails(details ...proto.Message) (*Status, error) {
+	if s.Code() == codes.OK {
+		return nil, errors.New("no error details for status with code OK")
+	}
+	// s.Code() != OK implies that s.Proto() != nil.
+	p := s.Proto()
+	for _, detail := range details {
+		any, err := ptypes.MarshalAny(detail)
+		if err != nil {
+			return nil, err
+		}
+		p.Details = append(p.Details, any)
+	}
+	return &Status{s: p}, nil
+}
+
+// Details returns a slice of details messages attached to the status.
+// If a detail cannot be decoded, the error is returned in place of the detail.
+func (s *Status) Details() []interface{} {
+	if s == nil || s.s == nil {
+		return nil
+	}
+	details := make([]interface{}, 0, len(s.s.Details))
+	for _, any := range s.s.Details {
+		detail := &ptypes.DynamicAny{}
+		if err := ptypes.UnmarshalAny(any, detail); err != nil {
+			details = append(details, err)
+			continue
+		}
+		details = append(details, detail.Message)
+	}
+	return details
+}
+
+func (s *Status) String() string {
+	return fmt.Sprintf("rpc error: code = %s desc = %s", s.Code(), s.Message())
+}
+
+// Error wraps a pointer of a status proto. It implements error and Status,
+// and a nil *Error should never be returned by this package.
+type Error struct {
+	s *Status
+}
+
+func (e *Error) Error() string {
+	return e.s.String()
+}
+
+// GRPCStatus returns the Status represented by se.
+func (e *Error) GRPCStatus() *Status {
+	return e.s
+}
+
+// Is implements future error.Is functionality.
+// A Error is equivalent if the code and message are identical.
+func (e *Error) Is(target error) bool {
+	tse, ok := target.(*Error)
+	if !ok {
+		return false
+	}
+	return proto.Equal(e.s.s, tse.s.s)
+}

vendor/google.golang.org/grpc/internal/syscall/syscall_linux.go

@@ -1,5 +1,3 @@
-// +build !appengine
-
 /*
  *
  * Copyright 2018 gRPC authors.
@@ -32,35 +30,35 @@ import (
 	"google.golang.org/grpc/grpclog"
 )
 
+var logger = grpclog.Component("core")
+
 // GetCPUTime returns the how much CPU time has passed since the start of this process.
 func GetCPUTime() int64 {
 	var ts unix.Timespec
 	if err := unix.ClockGettime(unix.CLOCK_PROCESS_CPUTIME_ID, &ts); err != nil {
-		grpclog.Fatal(err)
+		logger.Fatal(err)
 	}
 	return ts.Nano()
 }
 
-// Rusage is an alias for syscall.Rusage under linux non-appengine environment.
-type Rusage syscall.Rusage
+// Rusage is an alias for syscall.Rusage under linux environment.
+type Rusage = syscall.Rusage
 
 // GetRusage returns the resource usage of current process.
-func GetRusage() (rusage *Rusage) {
-	rusage = new(Rusage)
-	syscall.Getrusage(syscall.RUSAGE_SELF, (*syscall.Rusage)(rusage))
-	return
+func GetRusage() *Rusage {
+	rusage := new(Rusage)
+	syscall.Getrusage(syscall.RUSAGE_SELF, rusage)
+	return rusage
 }
 
 // CPUTimeDiff returns the differences of user CPU time and system CPU time used
 // between two Rusage structs.
 func CPUTimeDiff(first *Rusage, latest *Rusage) (float64, float64) {
-	f := (*syscall.Rusage)(first)
-	l := (*syscall.Rusage)(latest)
 	var (
-		utimeDiffs  = l.Utime.Sec - f.Utime.Sec
-		utimeDiffus = l.Utime.Usec - f.Utime.Usec
-		stimeDiffs  = l.Stime.Sec - f.Stime.Sec
-		stimeDiffus = l.Stime.Usec - f.Stime.Usec
+		utimeDiffs  = latest.Utime.Sec - first.Utime.Sec
+		utimeDiffus = latest.Utime.Usec - first.Utime.Usec
+		stimeDiffs  = latest.Stime.Sec - first.Stime.Sec
+		stimeDiffus = latest.Stime.Usec - first.Stime.Usec
 	)
 
 	uTimeElapsed := float64(utimeDiffs) + float64(utimeDiffus)*1.0e-6

vendor/google.golang.org/grpc/internal/syscall/syscall_nonlinux.go

@@ -1,4 +1,5 @@
-// +build !linux appengine
+//go:build !linux
+// +build !linux
 
 /*
  *
@@ -18,6 +19,8 @@
  *
  */
 
+// Package syscall provides functionalities that grpc uses to get low-level
+// operating system stats/info.
 package syscall
 
 import (
@@ -29,44 +32,45 @@ import (
 )
 
 var once sync.Once
+var logger = grpclog.Component("core")
 
 func log() {
 	once.Do(func() {
-		grpclog.Info("CPU time info is unavailable on non-linux or appengine environment.")
+		logger.Info("CPU time info is unavailable on non-linux environments.")
 	})
 }
 
-// GetCPUTime returns the how much CPU time has passed since the start of this process.
-// It always returns 0 under non-linux or appengine environment.
+// GetCPUTime returns the how much CPU time has passed since the start of this
+// process. It always returns 0 under non-linux environments.
 func GetCPUTime() int64 {
 	log()
 	return 0
 }
 
-// Rusage is an empty struct under non-linux or appengine environment.
+// Rusage is an empty struct under non-linux environments.
 type Rusage struct{}
 
-// GetRusage is a no-op function under non-linux or appengine environment.
-func GetRusage() (rusage *Rusage) {
+// GetRusage is a no-op function under non-linux environments.
+func GetRusage() *Rusage {
 	log()
 	return nil
 }
 
 // CPUTimeDiff returns the differences of user CPU time and system CPU time used
-// between two Rusage structs. It a no-op function for non-linux or appengine environment.
+// between two Rusage structs. It a no-op function for non-linux environments.
 func CPUTimeDiff(first *Rusage, latest *Rusage) (float64, float64) {
 	log()
 	return 0, 0
 }
 
-// SetTCPUserTimeout is a no-op function under non-linux or appengine environments
+// SetTCPUserTimeout is a no-op function under non-linux environments.
 func SetTCPUserTimeout(conn net.Conn, timeout time.Duration) error {
 	log()
 	return nil
 }
 
-// GetTCPUserTimeout is a no-op function under non-linux or appengine environments
-// a negative return value indicates the operation is not supported
+// GetTCPUserTimeout is a no-op function under non-linux environments.
+// A negative return value indicates the operation is not supported
 func GetTCPUserTimeout(conn net.Conn) (int, error) {
 	log()
 	return -1, nil

vendor/google.golang.org/grpc/internal/transport/controlbuf.go

@@ -20,13 +20,17 @@ package transport
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"runtime"
+	"strconv"
 	"sync"
 	"sync/atomic"
 
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
+	"google.golang.org/grpc/internal/grpcutil"
+	"google.golang.org/grpc/status"
 )
 
 var updateHeaderTblSize = func(e *hpack.Encoder, v uint32) {
@@ -128,6 +132,16 @@ type cleanupStream struct {
 
 func (c *cleanupStream) isTransportResponseFrame() bool { return c.rst } // Results in a RST_STREAM
 
+type earlyAbortStream struct {
+	httpStatus     uint32
+	streamID       uint32
+	contentSubtype string
+	status         *status.Status
+	rst            bool
+}
+
+func (*earlyAbortStream) isTransportResponseFrame() bool { return false }
+
 type dataFrame struct {
 	streamID  uint32
 	endStream bool
@@ -284,7 +298,7 @@ type controlBuffer struct {
 	// closed and nilled when transportResponseFrames drops below the
 	// threshold.  Both fields are protected by mu.
 	transportResponseFrames int
-	trfChan                 atomic.Value // *chan struct{}
+	trfChan                 atomic.Value // chan struct{}
 }
 
 func newControlBuffer(done <-chan struct{}) *controlBuffer {
@@ -298,10 +312,10 @@ func newControlBuffer(done <-chan struct{}) *controlBuffer {
 // throttle blocks if there are too many incomingSettings/cleanupStreams in the
 // controlbuf.
 func (c *controlBuffer) throttle() {
-	ch, _ := c.trfChan.Load().(*chan struct{})
+	ch, _ := c.trfChan.Load().(chan struct{})
 	if ch != nil {
 		select {
-		case <-*ch:
+		case <-ch:
 		case <-c.done:
 		}
 	}
@@ -335,8 +349,7 @@ func (c *controlBuffer) executeAndPut(f func(it interface{}) bool, it cbItem) (b
 		if c.transportResponseFrames == maxQueuedTransportResponseFrames {
 			// We are adding the frame that puts us over the threshold; create
 			// a throttling channel.
-			ch := make(chan struct{})
-			c.trfChan.Store(&ch)
+			c.trfChan.Store(make(chan struct{}))
 		}
 	}
 	c.mu.Unlock()
@@ -377,9 +390,9 @@ func (c *controlBuffer) get(block bool) (interface{}, error) {
 				if c.transportResponseFrames == maxQueuedTransportResponseFrames {
 					// We are removing the frame that put us over the
 					// threshold; close and clear the throttling channel.
-					ch := c.trfChan.Load().(*chan struct{})
-					close(*ch)
-					c.trfChan.Store((*chan struct{})(nil))
+					ch := c.trfChan.Load().(chan struct{})
+					close(ch)
+					c.trfChan.Store((chan struct{})(nil))
 				}
 				c.transportResponseFrames--
 			}
@@ -395,7 +408,6 @@ func (c *controlBuffer) get(block bool) (interface{}, error) {
 		select {
 		case <-c.ch:
 		case <-c.done:
-			c.finish()
 			return nil, ErrConnClosing
 		}
 	}
@@ -420,6 +432,14 @@ func (c *controlBuffer) finish() {
 			hdr.onOrphaned(ErrConnClosing)
 		}
 	}
+	// In case throttle() is currently in flight, it needs to be unblocked.
+	// Otherwise, the transport may not close, since the transport is closed by
+	// the reader encountering the connection error.
+	ch, _ := c.trfChan.Load().(chan struct{})
+	if ch != nil {
+		close(ch)
+	}
+	c.trfChan.Store((chan struct{})(nil))
 	c.mu.Unlock()
 }
 
@@ -505,7 +525,9 @@ func (l *loopyWriter) run() (err error) {
 			// 1. When the connection is closed by some other known issue.
 			// 2. User closed the connection.
 			// 3. A graceful close of connection.
-			infof("transport: loopyWriter.run returning. %v", err)
+			if logger.V(logLevel) {
+				logger.Infof("transport: loopyWriter.run returning. %v", err)
+			}
 			err = nil
 		}
 	}()
@@ -605,7 +627,9 @@ func (l *loopyWriter) headerHandler(h *headerFrame) error {
 	if l.side == serverSide {
 		str, ok := l.estdStreams[h.streamID]
 		if !ok {
-			warningf("transport: loopy doesn't recognize the stream: %d", h.streamID)
+			if logger.V(logLevel) {
+				logger.Warningf("transport: loopy doesn't recognize the stream: %d", h.streamID)
+			}
 			return nil
 		}
 		// Case 1.A: Server is responding back with headers.
@@ -658,7 +682,9 @@ func (l *loopyWriter) writeHeader(streamID uint32, endStream bool, hf []hpack.He
 	l.hBuf.Reset()
 	for _, f := range hf {
 		if err := l.hEnc.WriteField(f); err != nil {
-			warningf("transport: loopyWriter.writeHeader encountered error while encoding headers:", err)
+			if logger.V(logLevel) {
+				logger.Warningf("transport: loopyWriter.writeHeader encountered error while encoding headers: %v", err)
+			}
 		}
 	}
 	var (
@@ -743,6 +769,32 @@ func (l *loopyWriter) cleanupStreamHandler(c *cleanupStream) error {
 	return nil
 }
 
+func (l *loopyWriter) earlyAbortStreamHandler(eas *earlyAbortStream) error {
+	if l.side == clientSide {
+		return errors.New("earlyAbortStream not handled on client")
+	}
+	// In case the caller forgets to set the http status, default to 200.
+	if eas.httpStatus == 0 {
+		eas.httpStatus = 200
+	}
+	headerFields := []hpack.HeaderField{
+		{Name: ":status", Value: strconv.Itoa(int(eas.httpStatus))},
+		{Name: "content-type", Value: grpcutil.ContentType(eas.contentSubtype)},
+		{Name: "grpc-status", Value: strconv.Itoa(int(eas.status.Code()))},
+		{Name: "grpc-message", Value: encodeGrpcMessage(eas.status.Message())},
+	}
+
+	if err := l.writeHeader(eas.streamID, true, headerFields, nil); err != nil {
+		return err
+	}
+	if eas.rst {
+		if err := l.framer.fr.WriteRSTStream(eas.streamID, http2.ErrCodeNo); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 func (l *loopyWriter) incomingGoAwayHandler(*incomingGoAway) error {
 	if l.side == clientSide {
 		l.draining = true
@@ -781,6 +833,8 @@ func (l *loopyWriter) handle(i interface{}) error {
 		return l.registerStreamHandler(i)
 	case *cleanupStream:
 		return l.cleanupStreamHandler(i)
+	case *earlyAbortStream:
+		return l.earlyAbortStreamHandler(i)
 	case *incomingGoAway:
 		return l.incomingGoAwayHandler(i)
 	case *dataFrame:
@@ -857,38 +911,45 @@ func (l *loopyWriter) processData() (bool, error) {
 		return false, nil
 	}
 	var (
-		idx int
 		buf []byte
 	)
-	if len(dataItem.h) != 0 { // data header has not been written out yet.
-		buf = dataItem.h
-	} else {
-		idx = 1
-		buf = dataItem.d
-	}
-	size := http2MaxFrameLen
-	if len(buf) < size {
-		size = len(buf)
-	}
+	// Figure out the maximum size we can send
+	maxSize := http2MaxFrameLen
 	if strQuota := int(l.oiws) - str.bytesOutStanding; strQuota <= 0 { // stream-level flow control.
 		str.state = waitingOnStreamQuota
 		return false, nil
-	} else if strQuota < size {
-		size = strQuota
+	} else if maxSize > strQuota {
+		maxSize = strQuota
+	}
+	if maxSize > int(l.sendQuota) { // connection-level flow control.
+		maxSize = int(l.sendQuota)
+	}
+	// Compute how much of the header and data we can send within quota and max frame length
+	hSize := min(maxSize, len(dataItem.h))
+	dSize := min(maxSize-hSize, len(dataItem.d))
+	if hSize != 0 {
+		if dSize == 0 {
+			buf = dataItem.h
+		} else {
+			// We can add some data to grpc message header to distribute bytes more equally across frames.
+			// Copy on the stack to avoid generating garbage
+			var localBuf [http2MaxFrameLen]byte
+			copy(localBuf[:hSize], dataItem.h)
+			copy(localBuf[hSize:], dataItem.d[:dSize])
+			buf = localBuf[:hSize+dSize]
+		}
+	} else {
+		buf = dataItem.d
 	}
 
-	if l.sendQuota < uint32(size) { // connection-level flow control.
-		size = int(l.sendQuota)
-	}
+	size := hSize + dSize
+
 	// Now that outgoing flow controls are checked we can replenish str's write quota
 	str.wq.replenish(size)
 	var endStream bool
 	// If this is the last data message on this stream and all of it can be written in this iteration.
-	if dataItem.endStream && size == len(buf) {
-		// buf contains either data or it contains header but data is empty.
-		if idx == 1 || len(dataItem.d) == 0 {
-			endStream = true
-		}
+	if dataItem.endStream && len(dataItem.h)+len(dataItem.d) <= size {
+		endStream = true
 	}
 	if dataItem.onEachWrite != nil {
 		dataItem.onEachWrite()
@@ -896,14 +957,10 @@ func (l *loopyWriter) processData() (bool, error) {
 	if err := l.framer.fr.WriteData(dataItem.streamID, endStream, buf[:size]); err != nil {
 		return false, err
 	}
-	buf = buf[size:]
 	str.bytesOutStanding += size
 	l.sendQuota -= uint32(size)
-	if idx == 0 {
-		dataItem.h = buf
-	} else {
-		dataItem.d = buf
-	}
+	dataItem.h = dataItem.h[hSize:]
+	dataItem.d = dataItem.d[dSize:]
 
 	if len(dataItem.h) == 0 && len(dataItem.d) == 0 { // All the data from that message was written out.
 		str.itl.dequeue()
@@ -924,3 +981,10 @@ func (l *loopyWriter) processData() (bool, error) {
 	}
 	return false, nil
 }
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}

vendor/google.golang.org/grpc/internal/transport/flowcontrol.go

@@ -136,12 +136,10 @@ type inFlow struct {
 
 // newLimit updates the inflow window to a new value n.
 // It assumes that n is always greater than the old limit.
-func (f *inFlow) newLimit(n uint32) uint32 {
+func (f *inFlow) newLimit(n uint32) {
 	f.mu.Lock()
-	d := n - f.limit
 	f.limit = n
 	f.mu.Unlock()
-	return d
 }
 
 func (f *inFlow) maybeAdjust(n uint32) uint32 {

vendor/google.golang.org/grpc/internal/transport/handler_server.go

@@ -39,6 +39,7 @@ import (
 	"golang.org/x/net/http2"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/internal/grpcutil"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
 	"google.golang.org/grpc/stats"
@@ -48,7 +49,7 @@ import (
 // NewServerHandlerTransport returns a ServerTransport handling gRPC
 // from inside an http.Handler. It requires that the http Server
 // supports HTTP/2.
-func NewServerHandlerTransport(w http.ResponseWriter, r *http.Request, stats stats.Handler) (ServerTransport, error) {
+func NewServerHandlerTransport(w http.ResponseWriter, r *http.Request, stats []stats.Handler) (ServerTransport, error) {
 	if r.ProtoMajor != 2 {
 		return nil, errors.New("gRPC requires HTTP/2")
 	}
@@ -57,7 +58,7 @@ func NewServerHandlerTransport(w http.ResponseWriter, r *http.Request, stats sta
 	}
 	contentType := r.Header.Get("Content-Type")
 	// TODO: do we assume contentType is lowercase? we did before
-	contentSubtype, validContentType := contentSubtype(contentType)
+	contentSubtype, validContentType := grpcutil.ContentSubtype(contentType)
 	if !validContentType {
 		return nil, errors.New("invalid gRPC request content-type")
 	}
@@ -112,11 +113,10 @@ func NewServerHandlerTransport(w http.ResponseWriter, r *http.Request, stats sta
 // at this point to be speaking over HTTP/2, so it's able to speak valid
 // gRPC.
 type serverHandlerTransport struct {
-	rw               http.ResponseWriter
-	req              *http.Request
-	timeoutSet       bool
-	timeout          time.Duration
-	didCommonHeaders bool
+	rw         http.ResponseWriter
+	req        *http.Request
+	timeoutSet bool
+	timeout    time.Duration
 
 	headerMD metadata.MD
 
@@ -138,12 +138,11 @@ type serverHandlerTransport struct {
 	// TODO make sure this is consistent across handler_server and http2_server
 	contentSubtype string
 
-	stats stats.Handler
+	stats []stats.Handler
 }
 
-func (ht *serverHandlerTransport) Close() error {
+func (ht *serverHandlerTransport) Close() {
 	ht.closeOnce.Do(ht.closeCloseChanOnce)
-	return nil
 }
 
 func (ht *serverHandlerTransport) closeCloseChanOnce() { close(ht.closedCh) }
@@ -186,8 +185,11 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, st *status.Status) erro
 	ht.writeStatusMu.Lock()
 	defer ht.writeStatusMu.Unlock()
 
+	headersWritten := s.updateHeaderSent()
 	err := ht.do(func() {
-		ht.writeCommonHeaders(s)
+		if !headersWritten {
+			ht.writePendingHeaders(s)
+		}
 
 		// And flush, in case no header or body has been sent yet.
 		// This forces a separation of headers and trailers if this is the
@@ -226,8 +228,10 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, st *status.Status) erro
 	})
 
 	if err == nil { // transport has not been closed
-		if ht.stats != nil {
-			ht.stats.HandleRPC(s.Context(), &stats.OutTrailer{
+		// Note: The trailer fields are compressed with hpack after this call returns.
+		// No WireLength field is set here.
+		for _, sh := range ht.stats {
+			sh.HandleRPC(s.Context(), &stats.OutTrailer{
 				Trailer: s.trailer.Copy(),
 			})
 		}
@@ -236,14 +240,16 @@ func (ht *serverHandlerTransport) WriteStatus(s *Stream, st *status.Status) erro
 	return err
 }
 
+// writePendingHeaders sets common and custom headers on the first
+// write call (Write, WriteHeader, or WriteStatus)
+func (ht *serverHandlerTransport) writePendingHeaders(s *Stream) {
+	ht.writeCommonHeaders(s)
+	ht.writeCustomHeaders(s)
+}
+
 // writeCommonHeaders sets common headers on the first write
 // call (Write, WriteHeader, or WriteStatus).
 func (ht *serverHandlerTransport) writeCommonHeaders(s *Stream) {
-	if ht.didCommonHeaders {
-		return
-	}
-	ht.didCommonHeaders = true
-
 	h := ht.rw.Header()
 	h["Date"] = nil // suppress Date to make tests happy; TODO: restore
 	h.Set("Content-Type", ht.contentType)
@@ -262,9 +268,30 @@ func (ht *serverHandlerTransport) writeCommonHeaders(s *Stream) {
 	}
 }
 
+// writeCustomHeaders sets custom headers set on the stream via SetHeader
+// on the first write call (Write, WriteHeader, or WriteStatus).
+func (ht *serverHandlerTransport) writeCustomHeaders(s *Stream) {
+	h := ht.rw.Header()
+
+	s.hdrMu.Lock()
+	for k, vv := range s.header {
+		if isReservedHeader(k) {
+			continue
+		}
+		for _, v := range vv {
+			h.Add(k, encodeMetadataHeader(k, v))
+		}
+	}
+
+	s.hdrMu.Unlock()
+}
+
 func (ht *serverHandlerTransport) Write(s *Stream, hdr []byte, data []byte, opts *Options) error {
+	headersWritten := s.updateHeaderSent()
 	return ht.do(func() {
-		ht.writeCommonHeaders(s)
+		if !headersWritten {
+			ht.writePendingHeaders(s)
+		}
 		ht.rw.Write(hdr)
 		ht.rw.Write(data)
 		ht.rw.(http.Flusher).Flush()
@@ -272,27 +299,27 @@ func (ht *serverHandlerTransport) Write(s *Stream, hdr []byte, data []byte, opts
 }
 
 func (ht *serverHandlerTransport) WriteHeader(s *Stream, md metadata.MD) error {
+	if err := s.SetHeader(md); err != nil {
+		return err
+	}
+
+	headersWritten := s.updateHeaderSent()
 	err := ht.do(func() {
-		ht.writeCommonHeaders(s)
-		h := ht.rw.Header()
-		for k, vv := range md {
-			// Clients don't tolerate reading restricted headers after some non restricted ones were sent.
-			if isReservedHeader(k) {
-				continue
-			}
-			for _, v := range vv {
-				v = encodeMetadataHeader(k, v)
-				h.Add(k, v)
-			}
+		if !headersWritten {
+			ht.writePendingHeaders(s)
 		}
+
 		ht.rw.WriteHeader(200)
 		ht.rw.(http.Flusher).Flush()
 	})
 
 	if err == nil {
-		if ht.stats != nil {
-			ht.stats.HandleRPC(s.Context(), &stats.OutHeader{
-				Header: md.Copy(),
+		for _, sh := range ht.stats {
+			// Note: The header fields are compressed with hpack after this call returns.
+			// No WireLength field is set here.
+			sh.HandleRPC(s.Context(), &stats.OutHeader{
+				Header:      md.Copy(),
+				Compression: s.sendCompress,
 			})
 		}
 	}
@@ -338,18 +365,18 @@ func (ht *serverHandlerTransport) HandleStreams(startStream func(*Stream), trace
 		Addr: ht.RemoteAddr(),
 	}
 	if req.TLS != nil {
-		pr.AuthInfo = credentials.TLSInfo{State: *req.TLS, CommonAuthInfo: credentials.CommonAuthInfo{credentials.PrivacyAndIntegrity}}
+		pr.AuthInfo = credentials.TLSInfo{State: *req.TLS, CommonAuthInfo: credentials.CommonAuthInfo{SecurityLevel: credentials.PrivacyAndIntegrity}}
 	}
 	ctx = metadata.NewIncomingContext(ctx, ht.headerMD)
 	s.ctx = peer.NewContext(ctx, pr)
-	if ht.stats != nil {
-		s.ctx = ht.stats.TagRPC(s.ctx, &stats.RPCTagInfo{FullMethodName: s.method})
+	for _, sh := range ht.stats {
+		s.ctx = sh.TagRPC(s.ctx, &stats.RPCTagInfo{FullMethodName: s.method})
 		inHeader := &stats.InHeader{
 			FullMethod:  s.method,
 			RemoteAddr:  ht.RemoteAddr(),
 			Compression: s.recvCompress,
 		}
-		ht.stats.HandleRPC(s.ctx, inHeader)
+		sh.HandleRPC(s.ctx, inHeader)
 	}
 	s.trReader = &transportReader{
 		reader:        &recvBufferReader{ctx: s.ctx, ctxDone: s.ctx.Done(), recv: s.buf, freeBuffer: func(*bytes.Buffer) {}},

vendor/google.golang.org/grpc/internal/transport/http2_client.go

@@ -24,6 +24,8 @@ import (
 	"io"
 	"math"
 	"net"
+	"net/http"
+	"path/filepath"
 	"strconv"
 	"strings"
 	"sync"
@@ -32,15 +34,18 @@ import (
 
 	"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/internal"
 	"google.golang.org/grpc/internal/channelz"
+	icredentials "google.golang.org/grpc/internal/credentials"
+	"google.golang.org/grpc/internal/grpcutil"
+	imetadata "google.golang.org/grpc/internal/metadata"
 	"google.golang.org/grpc/internal/syscall"
+	"google.golang.org/grpc/internal/transport/networktype"
 	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
 	"google.golang.org/grpc/peer"
+	"google.golang.org/grpc/resolver"
 	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/status"
 )
@@ -57,7 +62,7 @@ type http2Client struct {
 	cancel     context.CancelFunc
 	ctxDone    <-chan struct{} // Cache the ctx.Done() chan.
 	userAgent  string
-	md         interface{}
+	md         metadata.MD
 	conn       net.Conn // underlying communication channel
 	loopy      *loopyWriter
 	remoteAddr net.Addr
@@ -85,7 +90,7 @@ type http2Client struct {
 	kp               keepalive.ClientParameters
 	keepaliveEnabled bool
 
-	statsHandler stats.Handler
+	statsHandlers []stats.Handler
 
 	initialWindowSize int32
 
@@ -112,6 +117,9 @@ type http2Client struct {
 	// goAwayReason records the http2.ErrCode and debug data received with the
 	// GoAway frame.
 	goAwayReason GoAwayReason
+	// goAwayDebugMessage contains a detailed human readable string about a
+	// GoAway frame, useful for error messages.
+	goAwayDebugMessage string
 	// A condition variable used to signal when the keepalive goroutine should
 	// go dormant. The condition for dormancy is based on the number of active
 	// streams and the `PermitWithoutStream` keepalive client parameter. And
@@ -124,7 +132,7 @@ type http2Client struct {
 	kpDormant bool
 
 	// Fields below are for channelz metric collection.
-	channelzID int64 // channelz unique identification number
+	channelzID *channelz.Identifier
 	czData     *channelzData
 
 	onGoAway func(GoAwayReason)
@@ -135,11 +143,34 @@ type http2Client struct {
 	connectionID uint64
 }
 
-func dial(ctx context.Context, fn func(context.Context, string) (net.Conn, error), addr string) (net.Conn, error) {
+func dial(ctx context.Context, fn func(context.Context, string) (net.Conn, error), addr resolver.Address, useProxy bool, grpcUA string) (net.Conn, error) {
+	address := addr.Addr
+	networkType, ok := networktype.Get(addr)
 	if fn != nil {
-		return fn(ctx, addr)
+		// Special handling for unix scheme with custom dialer. Back in the day,
+		// we did not have a unix resolver and therefore targets with a unix
+		// scheme would end up using the passthrough resolver. So, user's used a
+		// custom dialer in this case and expected the original dial target to
+		// be passed to the custom dialer. Now, we have a unix resolver. But if
+		// a custom dialer is specified, we want to retain the old behavior in
+		// terms of the address being passed to the custom dialer.
+		if networkType == "unix" && !strings.HasPrefix(address, "\x00") {
+			// Supported unix targets are either "unix://absolute-path" or
+			// "unix:relative-path".
+			if filepath.IsAbs(address) {
+				return fn(ctx, "unix://"+address)
+			}
+			return fn(ctx, "unix:"+address)
+		}
+		return fn(ctx, address)
 	}
-	return (&net.Dialer{}).DialContext(ctx, "tcp", addr)
+	if !ok {
+		networkType, address = parseDialTarget(address)
+	}
+	if networkType == "tcp" && useProxy {
+		return proxyDial(ctx, address, grpcUA)
+	}
+	return (&net.Dialer{}).DialContext(ctx, networkType, address)
 }
 
 func isTemporary(err error) bool {
@@ -161,7 +192,7 @@ func isTemporary(err error) bool {
 // newHTTP2Client constructs a connected ClientTransport to addr based on HTTP2
 // and starts to receive messages on it. Non-nil error returns if construction
 // fails.
-func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts ConnectOptions, onPrefaceReceipt func(), onGoAway func(GoAwayReason), onClose func()) (_ *http2Client, err error) {
+func newHTTP2Client(connectCtx, ctx context.Context, addr resolver.Address, opts ConnectOptions, onPrefaceReceipt func(), onGoAway func(GoAwayReason), onClose func()) (_ *http2Client, err error) {
 	scheme := "http"
 	ctx, cancel := context.WithCancel(ctx)
 	defer func() {
@@ -170,7 +201,13 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 		}
 	}()
 
-	conn, err := dial(connectCtx, opts.Dialer, addr.Addr)
+	// gRPC, resolver, balancer etc. can specify arbitrary data in the
+	// Attributes field of resolver.Address, which is shoved into connectCtx
+	// and passed to the dialer and credential handshaker. This makes it possible for
+	// address specific arbitrary data to reach custom dialers and credential handshakers.
+	connectCtx = icredentials.NewClientHandshakeInfoContext(connectCtx, credentials.ClientHandshakeInfo{Attributes: addr.Attributes})
+
+	conn, err := dial(connectCtx, opts.Dialer, addr, opts.UseProxy, opts.UserAgent)
 	if err != nil {
 		if opts.FailOnNonTempDialError {
 			return nil, connectionErrorf(isTemporary(err), err, "transport: error while dialing: %v", err)
@@ -214,12 +251,34 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 		}
 	}
 	if transportCreds != nil {
-		scheme = "https"
-		conn, authInfo, err = transportCreds.ClientHandshake(connectCtx, addr.Authority, conn)
+		rawConn := conn
+		// Pull the deadline from the connectCtx, which will be used for
+		// timeouts in the authentication protocol handshake. Can ignore the
+		// boolean as the deadline will return the zero value, which will make
+		// the conn not timeout on I/O operations.
+		deadline, _ := connectCtx.Deadline()
+		rawConn.SetDeadline(deadline)
+		conn, authInfo, err = transportCreds.ClientHandshake(connectCtx, addr.ServerName, rawConn)
+		rawConn.SetDeadline(time.Time{})
 		if err != nil {
 			return nil, connectionErrorf(isTemporary(err), err, "transport: authentication handshake failed: %v", err)
 		}
+		for _, cd := range perRPCCreds {
+			if cd.RequireTransportSecurity() {
+				if ci, ok := authInfo.(interface {
+					GetCommonAuthInfo() credentials.CommonAuthInfo
+				}); ok {
+					secLevel := ci.GetCommonAuthInfo().SecurityLevel
+					if secLevel != credentials.InvalidSecurityLevel && secLevel < credentials.PrivacyAndIntegrity {
+						return nil, connectionErrorf(true, nil, "transport: cannot send secure credentials on an insecure connection")
+					}
+				}
+			}
+		}
 		isSecure = true
+		if transportCreds.Info().SecurityProtocol == "tls" {
+			scheme = "https"
+		}
 	}
 	dynamicWindow := true
 	icwz := int32(initialWindowSize)
@@ -238,7 +297,6 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 		ctxDone:               ctx.Done(), // Cache Done chan.
 		cancel:                cancel,
 		userAgent:             opts.UserAgent,
-		md:                    addr.Metadata,
 		conn:                  conn,
 		remoteAddr:            conn.RemoteAddr(),
 		localAddr:             conn.LocalAddr(),
@@ -253,7 +311,7 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 		isSecure:              isSecure,
 		perRPCCreds:           perRPCCreds,
 		kp:                    kp,
-		statsHandler:          opts.StatsHandler,
+		statsHandlers:         opts.StatsHandlers,
 		initialWindowSize:     initialWindowSize,
 		onPrefaceReceipt:      onPrefaceReceipt,
 		nextID:                1,
@@ -266,6 +324,12 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 		keepaliveEnabled:      keepaliveEnabled,
 		bufferPool:            newBufferPool(),
 	}
+
+	if md, ok := addr.Metadata.(*metadata.MD); ok {
+		t.md = *md
+	} else if md := imetadata.Get(addr); md != nil {
+		t.md = md
+	}
 	t.controlBuf = newControlBuffer(t.ctxDone)
 	if opts.InitialWindowSize >= defaultWindowSize {
 		t.initialWindowSize = opts.InitialWindowSize
@@ -277,18 +341,19 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 			updateFlowControl: t.updateFlowControl,
 		}
 	}
-	if t.statsHandler != nil {
-		t.ctx = t.statsHandler.TagConn(t.ctx, &stats.ConnTagInfo{
+	for _, sh := range t.statsHandlers {
+		t.ctx = sh.TagConn(t.ctx, &stats.ConnTagInfo{
 			RemoteAddr: t.remoteAddr,
 			LocalAddr:  t.localAddr,
 		})
 		connBegin := &stats.ConnBegin{
 			Client: true,
 		}
-		t.statsHandler.HandleConn(t.ctx, connBegin)
+		sh.HandleConn(t.ctx, connBegin)
 	}
-	if channelz.IsOn() {
-		t.channelzID = channelz.RegisterNormalSocket(t, opts.ChannelzParentID, fmt.Sprintf("%s -> %s", t.localAddr, t.remoteAddr))
+	t.channelzID, err = channelz.RegisterNormalSocket(t, opts.ChannelzParentID, fmt.Sprintf("%s -> %s", t.localAddr, t.remoteAddr))
+	if err != nil {
+		return nil, err
 	}
 	if t.keepaliveEnabled {
 		t.kpDormancyCond = sync.NewCond(&t.mu)
@@ -302,12 +367,14 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 	// Send connection preface to server.
 	n, err := t.conn.Write(clientPreface)
 	if err != nil {
-		t.Close()
-		return nil, connectionErrorf(true, err, "transport: failed to write client preface: %v", err)
+		err = connectionErrorf(true, err, "transport: failed to write client preface: %v", err)
+		t.Close(err)
+		return nil, err
 	}
 	if n != len(clientPreface) {
-		t.Close()
-		return nil, connectionErrorf(true, err, "transport: preface mismatch, wrote %d bytes; want %d", n, len(clientPreface))
+		err = connectionErrorf(true, nil, "transport: preface mismatch, wrote %d bytes; want %d", n, len(clientPreface))
+		t.Close(err)
+		return nil, err
 	}
 	var ss []http2.Setting
 
@@ -325,14 +392,16 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 	}
 	err = t.framer.fr.WriteSettings(ss...)
 	if err != nil {
-		t.Close()
-		return nil, connectionErrorf(true, err, "transport: failed to write initial settings frame: %v", err)
+		err = connectionErrorf(true, err, "transport: failed to write initial settings frame: %v", err)
+		t.Close(err)
+		return nil, err
 	}
 	// Adjust the connection flow control window if needed.
 	if delta := uint32(icwz - defaultWindowSize); delta > 0 {
 		if err := t.framer.fr.WriteWindowUpdate(0, delta); err != nil {
-			t.Close()
-			return nil, connectionErrorf(true, err, "transport: failed to write window update: %v", err)
+			err = connectionErrorf(true, err, "transport: failed to write window update: %v", err)
+			t.Close(err)
+			return nil, err
 		}
 	}
 
@@ -345,13 +414,14 @@ func newHTTP2Client(connectCtx, ctx context.Context, addr TargetInfo, opts Conne
 		t.loopy = newLoopyWriter(clientSide, t.framer, t.controlBuf, t.bdpEst)
 		err := t.loopy.run()
 		if err != nil {
-			errorf("transport: loopyWriter.run returning. Err: %v", err)
-		}
-		// If it's a connection error, let reader goroutine handle it
-		// since there might be data in the buffers.
-		if _, ok := err.(net.Error); !ok {
-			t.conn.Close()
+			if logger.V(logLevel) {
+				logger.Errorf("transport: loopyWriter.run returning. Err: %v", err)
+			}
 		}
+		// Do not close the transport.  Let reader goroutine handle it since
+		// there might be data in the buffers.
+		t.conn.Close()
+		t.controlBuf.finish()
 		close(t.writerDone)
 	}()
 	return t, nil
@@ -367,6 +437,7 @@ func (t *http2Client) newStream(ctx context.Context, callHdr *CallHdr) *Stream {
 		buf:            newRecvBuffer(),
 		headerChan:     make(chan struct{}),
 		contentSubtype: callHdr.ContentSubtype,
+		doneFunc:       callHdr.DoneFunc,
 	}
 	s.wq = newWriteQuota(defaultWriteQuota, s.done)
 	s.requestRead = func(n int) {
@@ -406,7 +477,7 @@ func (t *http2Client) createHeaderFields(ctx context.Context, callHdr *CallHdr)
 		Method:   callHdr.Method,
 		AuthInfo: t.authInfo,
 	}
-	ctxWithRequestInfo := internal.NewRequestInfoContext.(func(context.Context, credentials.RequestInfo) context.Context)(ctx, ri)
+	ctxWithRequestInfo := icredentials.NewRequestInfoContext(ctx, ri)
 	authData, err := t.getTrAuthData(ctxWithRequestInfo, aud)
 	if err != nil {
 		return nil, err
@@ -425,7 +496,7 @@ func (t *http2Client) createHeaderFields(ctx context.Context, callHdr *CallHdr)
 	headerFields = append(headerFields, hpack.HeaderField{Name: ":scheme", Value: t.scheme})
 	headerFields = append(headerFields, hpack.HeaderField{Name: ":path", Value: callHdr.Method})
 	headerFields = append(headerFields, hpack.HeaderField{Name: ":authority", Value: callHdr.Host})
-	headerFields = append(headerFields, hpack.HeaderField{Name: "content-type", Value: contentType(callHdr.ContentSubtype)})
+	headerFields = append(headerFields, hpack.HeaderField{Name: "content-type", Value: grpcutil.ContentType(callHdr.ContentSubtype)})
 	headerFields = append(headerFields, hpack.HeaderField{Name: "user-agent", Value: t.userAgent})
 	headerFields = append(headerFields, hpack.HeaderField{Name: "te", Value: "trailers"})
 	if callHdr.PreviousAttempts > 0 {
@@ -440,7 +511,7 @@ func (t *http2Client) createHeaderFields(ctx context.Context, callHdr *CallHdr)
 		// Send out timeout regardless its value. The server can detect timeout context by itself.
 		// TODO(mmukhi): Perhaps this field should be updated when actually writing out to the wire.
 		timeout := time.Until(dl)
-		headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-timeout", Value: encodeTimeout(timeout)})
+		headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-timeout", Value: grpcutil.EncodeDuration(timeout)})
 	}
 	for k, v := range authData {
 		headerFields = append(headerFields, hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)})
@@ -469,25 +540,23 @@ func (t *http2Client) createHeaderFields(ctx context.Context, callHdr *CallHdr)
 		for _, vv := range added {
 			for i, v := range vv {
 				if i%2 == 0 {
-					k = v
+					k = strings.ToLower(v)
 					continue
 				}
 				// HTTP doesn't allow you to set pseudoheaders after non pseudoheaders were set.
 				if isReservedHeader(k) {
 					continue
 				}
-				headerFields = append(headerFields, hpack.HeaderField{Name: strings.ToLower(k), Value: encodeMetadataHeader(k, v)})
+				headerFields = append(headerFields, hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)})
 			}
 		}
 	}
-	if md, ok := t.md.(*metadata.MD); ok {
-		for k, vv := range *md {
-			if isReservedHeader(k) {
-				continue
-			}
-			for _, v := range vv {
-				headerFields = append(headerFields, hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)})
-			}
+	for k, vv := range t.md {
+		if isReservedHeader(k) {
+			continue
+		}
+		for _, v := range vv {
+			headerFields = append(headerFields, hpack.HeaderField{Name: k, Value: encodeMetadataHeader(k, v)})
 		}
 	}
 	return headerFields, nil
@@ -520,7 +589,7 @@ func (t *http2Client) getTrAuthData(ctx context.Context, audience string) (map[s
 				return nil, err
 			}
 
-			return nil, status.Errorf(codes.Unauthenticated, "transport: %v", err)
+			return nil, status.Errorf(codes.Unauthenticated, "transport: per-RPC creds failed due to error: %v", err)
 		}
 		for k, v := range data {
 			// Capital header names are illegal in HTTP/2.
@@ -537,8 +606,11 @@ func (t *http2Client) getCallAuthData(ctx context.Context, audience string, call
 	// Note: if these credentials are provided both via dial options and call
 	// options, then both sets of credentials will be applied.
 	if callCreds := callHdr.Creds; callCreds != nil {
-		if !t.isSecure && callCreds.RequireTransportSecurity() {
-			return nil, status.Error(codes.Unauthenticated, "transport: cannot send secure credentials on an insecure connection")
+		if callCreds.RequireTransportSecurity() {
+			ri, _ := credentials.RequestInfoFromContext(ctx)
+			if !t.isSecure || credentials.CheckSecurityLevel(ri.AuthInfo, credentials.PrivacyAndIntegrity) != nil {
+				return nil, status.Error(codes.Unauthenticated, "transport: cannot send secure credentials on an insecure connection")
+			}
 		}
 		data, err := callCreds.GetRequestMetadata(ctx, audience)
 		if err != nil {
@@ -554,13 +626,34 @@ func (t *http2Client) getCallAuthData(ctx context.Context, audience string, call
 	return callAuthData, nil
 }
 
+// NewStreamError wraps an error and reports additional information.  Typically
+// NewStream errors result in transparent retry, as they mean nothing went onto
+// the wire.  However, there are two notable exceptions:
+//
+// 1. If the stream headers violate the max header list size allowed by the
+//    server.  It's possible this could succeed on another transport, even if
+//    it's unlikely, but do not transparently retry.
+// 2. If the credentials errored when requesting their headers.  In this case,
+//    it's possible a retry can fix the problem, but indefinitely transparently
+//    retrying is not appropriate as it is likely the credentials, if they can
+//    eventually succeed, would need I/O to do so.
+type NewStreamError struct {
+	Err error
+
+	AllowTransparentRetry bool
+}
+
+func (e NewStreamError) Error() string {
+	return e.Err.Error()
+}
+
 // 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) {
+// streams.  All non-nil errors returned will be *NewStreamError.
+func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (*Stream, error) {
 	ctx = peer.NewContext(ctx, t.getPeer())
 	headerFields, err := t.createHeaderFields(ctx, callHdr)
 	if err != nil {
-		return nil, err
+		return nil, &NewStreamError{Err: err, AllowTransparentRetry: false}
 	}
 	s := t.newStream(ctx, callHdr)
 	cleanup := func(err error) {
@@ -660,36 +753,47 @@ func (t *http2Client) NewStream(ctx context.Context, callHdr *CallHdr) (_ *Strea
 			return true
 		}, hdr)
 		if err != nil {
-			return nil, err
+			// Connection closed.
+			return nil, &NewStreamError{Err: err, AllowTransparentRetry: true}
 		}
 		if success {
 			break
 		}
 		if hdrListSizeErr != nil {
-			return nil, hdrListSizeErr
+			return nil, &NewStreamError{Err: hdrListSizeErr}
 		}
 		firstTry = false
 		select {
 		case <-ch:
-		case <-s.ctx.Done():
-			return nil, ContextErr(s.ctx.Err())
+		case <-ctx.Done():
+			return nil, &NewStreamError{Err: ContextErr(ctx.Err())}
 		case <-t.goAway:
-			return nil, errStreamDrain
+			return nil, &NewStreamError{Err: errStreamDrain, AllowTransparentRetry: true}
 		case <-t.ctx.Done():
-			return nil, ErrConnClosing
+			return nil, &NewStreamError{Err: ErrConnClosing, AllowTransparentRetry: true}
 		}
 	}
-	if t.statsHandler != nil {
-		header, _, _ := metadata.FromOutgoingContextRaw(ctx)
-		outHeader := &stats.OutHeader{
-			Client:      true,
-			FullMethod:  callHdr.Method,
-			RemoteAddr:  t.remoteAddr,
-			LocalAddr:   t.localAddr,
-			Compression: callHdr.SendCompress,
-			Header:      header.Copy(),
+	if len(t.statsHandlers) != 0 {
+		header, ok := metadata.FromOutgoingContext(ctx)
+		if ok {
+			header.Set("user-agent", t.userAgent)
+		} else {
+			header = metadata.Pairs("user-agent", t.userAgent)
+		}
+		for _, sh := range t.statsHandlers {
+			// Note: The header fields are compressed with hpack after this call returns.
+			// No WireLength field is set here.
+			// Note: Creating a new stats object to prevent pollution.
+			outHeader := &stats.OutHeader{
+				Client:      true,
+				FullMethod:  callHdr.Method,
+				RemoteAddr:  t.remoteAddr,
+				LocalAddr:   t.localAddr,
+				Compression: callHdr.SendCompress,
+				Header:      header,
+			}
+			sh.HandleRPC(s.ctx, outHeader)
 		}
-		t.statsHandler.HandleRPC(s.ctx, outHeader)
 	}
 	return s, nil
 }
@@ -764,6 +868,9 @@ func (t *http2Client) closeStream(s *Stream, err error, rst bool, rstCode http2.
 	t.controlBuf.executeAndPut(addBackStreamQuota, cleanup)
 	// This will unblock write.
 	close(s.done)
+	if s.doneFunc != nil {
+		s.doneFunc()
+	}
 }
 
 // Close kicks off the shutdown process of the transport. This should be called
@@ -773,12 +880,12 @@ func (t *http2Client) closeStream(s *Stream, err error, rst bool, rstCode http2.
 // This method blocks until the addrConn that initiated this transport is
 // re-connected. This happens because t.onClose() begins reconnect logic at the
 // addrConn level and blocks until the addrConn is successfully connected.
-func (t *http2Client) Close() error {
+func (t *http2Client) Close(err error) {
 	t.mu.Lock()
 	// Make sure we only Close once.
 	if t.state == closing {
 		t.mu.Unlock()
-		return nil
+		return
 	}
 	// Call t.onClose before setting the state to closing to prevent the client
 	// from attempting to create new streams ASAP.
@@ -794,21 +901,30 @@ func (t *http2Client) Close() error {
 	t.mu.Unlock()
 	t.controlBuf.finish()
 	t.cancel()
-	err := t.conn.Close()
-	if channelz.IsOn() {
-		channelz.RemoveEntry(t.channelzID)
+	t.conn.Close()
+	channelz.RemoveEntry(t.channelzID)
+	// Append info about previous goaways if there were any, since this may be important
+	// for understanding the root cause for this connection to be closed.
+	_, goAwayDebugMessage := t.GetGoAwayReason()
+
+	var st *status.Status
+	if len(goAwayDebugMessage) > 0 {
+		st = status.Newf(codes.Unavailable, "closing transport due to: %v, received prior goaway: %v", err, goAwayDebugMessage)
+		err = st.Err()
+	} else {
+		st = status.New(codes.Unavailable, err.Error())
 	}
+
 	// Notify all active streams.
 	for _, s := range streams {
-		t.closeStream(s, ErrConnClosing, false, http2.ErrCodeNo, status.New(codes.Unavailable, ErrConnClosing.Desc), nil, false)
+		t.closeStream(s, err, false, http2.ErrCodeNo, st, nil, false)
 	}
-	if t.statsHandler != nil {
+	for _, sh := range t.statsHandlers {
 		connEnd := &stats.ConnEnd{
 			Client: true,
 		}
-		t.statsHandler.HandleConn(t.ctx, connEnd)
+		sh.HandleConn(t.ctx, connEnd)
 	}
-	return err
 }
 
 // GracefulClose sets the state to draining, which prevents new streams from
@@ -827,7 +943,7 @@ func (t *http2Client) GracefulClose() {
 	active := len(t.activeStreams)
 	t.mu.Unlock()
 	if active == 0 {
-		t.Close()
+		t.Close(ErrConnClosing)
 		return
 	}
 	t.controlBuf.put(&incomingGoAway{})
@@ -847,18 +963,10 @@ func (t *http2Client) Write(s *Stream, hdr []byte, data []byte, opts *Options) e
 	df := &dataFrame{
 		streamID:  s.id,
 		endStream: opts.Last,
+		h:         hdr,
+		d:         data,
 	}
-	if hdr != nil || data != nil { // If it's not an empty data frame.
-		// Add some data to grpc message header so that we can equally
-		// distribute bytes across frames.
-		emptyLen := http2MaxFrameLen - len(hdr)
-		if emptyLen > len(data) {
-			emptyLen = len(data)
-		}
-		hdr = append(hdr, data[:emptyLen]...)
-		data = data[emptyLen:]
-		df.h, df.d = hdr, data
-		// TODO(mmukhi): The above logic in this if can be moved to loopyWriter's data handler.
+	if hdr != nil || data != nil { // If it's not an empty data frame, check quota.
 		if err := s.wq.get(int32(len(hdr) + len(data))); err != nil {
 			return err
 		}
@@ -976,7 +1084,7 @@ func (t *http2Client) handleData(f *http2.DataFrame) {
 	}
 	// The server has closed the stream without sending trailers.  Record that
 	// the read direction is closed, and set the status appropriately.
-	if f.FrameHeader.Flags.Has(http2.FlagDataEndStream) {
+	if f.StreamEnded() {
 		t.closeStream(s, io.EOF, false, http2.ErrCodeNo, status.New(codes.Internal, "server closed the stream without sending trailers"), nil, true)
 	}
 }
@@ -992,7 +1100,9 @@ func (t *http2Client) handleRSTStream(f *http2.RSTStreamFrame) {
 	}
 	statusCode, ok := http2ErrConvTab[f.ErrCode]
 	if !ok {
-		warningf("transport: http2Client.handleRSTStream found no mapped gRPC status for the received http2 error %v", f.ErrCode)
+		if logger.V(logLevel) {
+			logger.Warningf("transport: http2Client.handleRSTStream found no mapped gRPC status for the received http2 error %v", f.ErrCode)
+		}
 		statusCode = codes.Unknown
 	}
 	if statusCode == codes.Canceled {
@@ -1074,12 +1184,14 @@ func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
 		return
 	}
 	if f.ErrCode == http2.ErrCodeEnhanceYourCalm {
-		infof("Client received GoAway with http2.ErrCodeEnhanceYourCalm.")
+		if logger.V(logLevel) {
+			logger.Infof("Client received GoAway with http2.ErrCodeEnhanceYourCalm.")
+		}
 	}
 	id := f.LastStreamID
-	if id > 0 && id%2 != 1 {
+	if id > 0 && id%2 == 0 {
 		t.mu.Unlock()
-		t.Close()
+		t.Close(connectionErrorf(true, nil, "received goaway with non-zero even-numbered numbered stream id: %v", id))
 		return
 	}
 	// A client can receive multiple GoAways from the server (see
@@ -1097,7 +1209,7 @@ func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
 		// If there are multiple GoAways the first one should always have an ID greater than the following ones.
 		if id > t.prevGoAwayID {
 			t.mu.Unlock()
-			t.Close()
+			t.Close(connectionErrorf(true, nil, "received goaway with stream id: %v, which exceeds stream id of previous goaway: %v", id, t.prevGoAwayID))
 			return
 		}
 	default:
@@ -1127,7 +1239,7 @@ func (t *http2Client) handleGoAway(f *http2.GoAwayFrame) {
 	active := len(t.activeStreams)
 	t.mu.Unlock()
 	if active == 0 {
-		t.Close()
+		t.Close(connectionErrorf(true, nil, "received goaway and there are no active streams"))
 	}
 }
 
@@ -1143,12 +1255,17 @@ func (t *http2Client) setGoAwayReason(f *http2.GoAwayFrame) {
 			t.goAwayReason = GoAwayTooManyPings
 		}
 	}
+	if len(f.DebugData()) == 0 {
+		t.goAwayDebugMessage = fmt.Sprintf("code: %s", f.ErrCode)
+	} else {
+		t.goAwayDebugMessage = fmt.Sprintf("code: %s, debug data: %q", f.ErrCode, string(f.DebugData()))
+	}
 }
 
-func (t *http2Client) GetGoAwayReason() GoAwayReason {
+func (t *http2Client) GetGoAwayReason() (GoAwayReason, string) {
 	t.mu.Lock()
 	defer t.mu.Unlock()
-	return t.goAwayReason
+	return t.goAwayReason, t.goAwayDebugMessage
 }
 
 func (t *http2Client) handleWindowUpdate(f *http2.WindowUpdateFrame) {
@@ -1175,34 +1292,128 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		return
 	}
 
-	state := &decodeState{}
-	// Initialize isGRPC value to be !initialHeader, since if a gRPC Response-Headers has already been received, then it means that the peer is speaking gRPC and we are in gRPC mode.
-	state.data.isGRPC = !initialHeader
-	if err := state.decodeHeader(frame); err != nil {
-		t.closeStream(s, err, true, http2.ErrCodeProtocol, status.Convert(err), nil, endStream)
+	// frame.Truncated is set to true when framer detects that the current header
+	// list size hits MaxHeaderListSize limit.
+	if frame.Truncated {
+		se := status.New(codes.Internal, "peer header list size exceeded limit")
+		t.closeStream(s, se.Err(), true, http2.ErrCodeFrameSize, se, nil, endStream)
+		return
+	}
+
+	var (
+		// If a gRPC Response-Headers has already been received, then it means
+		// that the peer is speaking gRPC and we are in gRPC mode.
+		isGRPC         = !initialHeader
+		mdata          = make(map[string][]string)
+		contentTypeErr = "malformed header: missing HTTP content-type"
+		grpcMessage    string
+		statusGen      *status.Status
+		recvCompress   string
+		httpStatusCode *int
+		httpStatusErr  string
+		rawStatusCode  = codes.Unknown
+		// headerError is set if an error is encountered while parsing the headers
+		headerError string
+	)
+
+	if initialHeader {
+		httpStatusErr = "malformed header: missing HTTP status"
+	}
+
+	for _, hf := range frame.Fields {
+		switch hf.Name {
+		case "content-type":
+			if _, validContentType := grpcutil.ContentSubtype(hf.Value); !validContentType {
+				contentTypeErr = fmt.Sprintf("transport: received unexpected content-type %q", hf.Value)
+				break
+			}
+			contentTypeErr = ""
+			mdata[hf.Name] = append(mdata[hf.Name], hf.Value)
+			isGRPC = true
+		case "grpc-encoding":
+			recvCompress = hf.Value
+		case "grpc-status":
+			code, err := strconv.ParseInt(hf.Value, 10, 32)
+			if err != nil {
+				se := status.New(codes.Internal, fmt.Sprintf("transport: malformed grpc-status: %v", err))
+				t.closeStream(s, se.Err(), true, http2.ErrCodeProtocol, se, nil, endStream)
+				return
+			}
+			rawStatusCode = codes.Code(uint32(code))
+		case "grpc-message":
+			grpcMessage = decodeGrpcMessage(hf.Value)
+		case "grpc-status-details-bin":
+			var err error
+			statusGen, err = decodeGRPCStatusDetails(hf.Value)
+			if err != nil {
+				headerError = fmt.Sprintf("transport: malformed grpc-status-details-bin: %v", err)
+			}
+		case ":status":
+			if hf.Value == "200" {
+				httpStatusErr = ""
+				statusCode := 200
+				httpStatusCode = &statusCode
+				break
+			}
+
+			c, err := strconv.ParseInt(hf.Value, 10, 32)
+			if err != nil {
+				se := status.New(codes.Internal, fmt.Sprintf("transport: malformed http-status: %v", err))
+				t.closeStream(s, se.Err(), true, http2.ErrCodeProtocol, se, nil, endStream)
+				return
+			}
+			statusCode := int(c)
+			httpStatusCode = &statusCode
+
+			httpStatusErr = fmt.Sprintf(
+				"unexpected HTTP status code received from server: %d (%s)",
+				statusCode,
+				http.StatusText(statusCode),
+			)
+		default:
+			if isReservedHeader(hf.Name) && !isWhitelistedHeader(hf.Name) {
+				break
+			}
+			v, err := decodeMetadataHeader(hf.Name, hf.Value)
+			if err != nil {
+				headerError = fmt.Sprintf("transport: malformed %s: %v", hf.Name, err)
+				logger.Warningf("Failed to decode metadata header (%q, %q): %v", hf.Name, hf.Value, err)
+				break
+			}
+			mdata[hf.Name] = append(mdata[hf.Name], v)
+		}
+	}
+
+	if !isGRPC || httpStatusErr != "" {
+		var code = codes.Internal // when header does not include HTTP status, return INTERNAL
+
+		if httpStatusCode != nil {
+			var ok bool
+			code, ok = HTTPStatusConvTab[*httpStatusCode]
+			if !ok {
+				code = codes.Unknown
+			}
+		}
+		var errs []string
+		if httpStatusErr != "" {
+			errs = append(errs, httpStatusErr)
+		}
+		if contentTypeErr != "" {
+			errs = append(errs, contentTypeErr)
+		}
+		// Verify the HTTP response is a 200.
+		se := status.New(code, strings.Join(errs, "; "))
+		t.closeStream(s, se.Err(), true, http2.ErrCodeProtocol, se, nil, endStream)
+		return
+	}
+
+	if headerError != "" {
+		se := status.New(codes.Internal, headerError)
+		t.closeStream(s, se.Err(), true, http2.ErrCodeProtocol, se, nil, endStream)
 		return
 	}
 
 	isHeader := false
-	defer func() {
-		if t.statsHandler != nil {
-			if isHeader {
-				inHeader := &stats.InHeader{
-					Client:     true,
-					WireLength: int(frame.Header().Length),
-					Header:     s.header.Copy(),
-				}
-				t.statsHandler.HandleRPC(s.ctx, inHeader)
-			} else {
-				inTrailer := &stats.InTrailer{
-					Client:     true,
-					WireLength: int(frame.Header().Length),
-					Trailer:    s.trailer.Copy(),
-				}
-				t.statsHandler.HandleRPC(s.ctx, inTrailer)
-			}
-		}
-	}()
 
 	// If headerChan hasn't been closed yet
 	if atomic.CompareAndSwapUint32(&s.headerChanClosed, 0, 1) {
@@ -1213,9 +1424,9 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 			// These values can be set without any synchronization because
 			// stream goroutine will read it only after seeing a closed
 			// headerChan which we'll close after setting this.
-			s.recvCompress = state.data.encoding
-			if len(state.data.mdata) > 0 {
-				s.header = state.data.mdata
+			s.recvCompress = recvCompress
+			if len(mdata) > 0 {
+				s.header = mdata
 			}
 		} else {
 			// HEADERS frame block carries a Trailers-Only.
@@ -1224,13 +1435,36 @@ func (t *http2Client) operateHeaders(frame *http2.MetaHeadersFrame) {
 		close(s.headerChan)
 	}
 
+	for _, sh := range t.statsHandlers {
+		if isHeader {
+			inHeader := &stats.InHeader{
+				Client:      true,
+				WireLength:  int(frame.Header().Length),
+				Header:      metadata.MD(mdata).Copy(),
+				Compression: s.recvCompress,
+			}
+			sh.HandleRPC(s.ctx, inHeader)
+		} else {
+			inTrailer := &stats.InTrailer{
+				Client:     true,
+				WireLength: int(frame.Header().Length),
+				Trailer:    metadata.MD(mdata).Copy(),
+			}
+			sh.HandleRPC(s.ctx, inTrailer)
+		}
+	}
+
 	if !endStream {
 		return
 	}
 
+	if statusGen == nil {
+		statusGen = status.New(rawStatusCode, grpcMessage)
+	}
+
 	// if client received END_STREAM from server while stream was still active, send RST_STREAM
 	rst := s.getState() == streamActive
-	t.closeStream(s, io.EOF, rst, http2.ErrCodeNo, state.status(), state.data.mdata, true)
+	t.closeStream(s, io.EOF, rst, http2.ErrCodeNo, statusGen, mdata, true)
 }
 
 // reader runs as a separate goroutine in charge of reading data from network
@@ -1244,7 +1478,8 @@ func (t *http2Client) reader() {
 	// Check the validity of server preface.
 	frame, err := t.framer.fr.ReadFrame()
 	if err != nil {
-		t.Close() // this kicks off resetTransport, so must be last before return
+		err = connectionErrorf(true, err, "error reading server preface: %v", err)
+		t.Close(err) // this kicks off resetTransport, so must be last before return
 		return
 	}
 	t.conn.SetReadDeadline(time.Time{}) // reset deadline once we get the settings frame (we didn't time out, yay!)
@@ -1253,7 +1488,8 @@ func (t *http2Client) reader() {
 	}
 	sf, ok := frame.(*http2.SettingsFrame)
 	if !ok {
-		t.Close() // this kicks off resetTransport, so must be last before return
+		// this kicks off resetTransport, so must be last before return
+		t.Close(connectionErrorf(true, nil, "initial http2 frame from server is not a settings frame: %T", frame))
 		return
 	}
 	t.onPrefaceReceipt()
@@ -1277,13 +1513,19 @@ func (t *http2Client) reader() {
 				if s != nil {
 					// use error detail to provide better err message
 					code := http2ErrConvTab[se.Code]
-					msg := t.framer.fr.ErrorDetail().Error()
+					errorDetail := t.framer.fr.ErrorDetail()
+					var msg string
+					if errorDetail != nil {
+						msg = errorDetail.Error()
+					} else {
+						msg = "received invalid frame"
+					}
 					t.closeStream(s, status.Error(code, msg), true, http2.ErrCodeProtocol, status.New(code, msg), nil, false)
 				}
 				continue
 			} else {
 				// Transport error.
-				t.Close()
+				t.Close(connectionErrorf(true, err, "error reading from server: %v", err))
 				return
 			}
 		}
@@ -1303,7 +1545,9 @@ func (t *http2Client) reader() {
 		case *http2.WindowUpdateFrame:
 			t.handleWindowUpdate(frame)
 		default:
-			errorf("transport: http2Client.reader got unhandled frame type %v.", frame)
+			if logger.V(logLevel) {
+				logger.Errorf("transport: http2Client.reader got unhandled frame type %v.", frame)
+			}
 		}
 	}
 }
@@ -1315,7 +1559,7 @@ func minTime(a, b time.Duration) time.Duration {
 	return b
 }
 
-// keepalive running in a separate goroutune makes sure the connection is alive by sending pings.
+// keepalive running in a separate goroutine makes sure the connection is alive by sending pings.
 func (t *http2Client) keepalive() {
 	p := &ping{data: [8]byte{}}
 	// True iff a ping has been sent, and no data has been received since then.
@@ -1340,7 +1584,7 @@ func (t *http2Client) keepalive() {
 				continue
 			}
 			if outstandingPing && timeoutLeft <= 0 {
-				t.Close()
+				t.Close(connectionErrorf(true, nil, "keepalive ping failed to receive ACK within timeout"))
 				return
 			}
 			t.mu.Lock()

vendor/google.golang.org/grpc/internal/transport/http2_server.go

@@ -21,11 +21,11 @@ package transport
 import (
 	"bytes"
 	"context"
-	"errors"
 	"fmt"
 	"io"
 	"math"
 	"net"
+	"net/http"
 	"strconv"
 	"sync"
 	"sync/atomic"
@@ -34,12 +34,11 @@ import (
 	"github.com/golang/protobuf/proto"
 	"golang.org/x/net/http2"
 	"golang.org/x/net/http2/hpack"
+	"google.golang.org/grpc/internal/grpcutil"
+	"google.golang.org/grpc/internal/syscall"
 
-	spb "google.golang.org/genproto/googleapis/rpc/status"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
-	"google.golang.org/grpc/grpclog"
-	"google.golang.org/grpc/internal"
 	"google.golang.org/grpc/internal/channelz"
 	"google.golang.org/grpc/internal/grpcrand"
 	"google.golang.org/grpc/keepalive"
@@ -53,13 +52,10 @@ import (
 var (
 	// ErrIllegalHeaderWrite indicates that setting header is illegal because of
 	// the stream's state.
-	ErrIllegalHeaderWrite = errors.New("transport: the stream is done or WriteHeader was already called")
+	ErrIllegalHeaderWrite = status.Error(codes.Internal, "transport: SendHeader called multiple times")
 	// ErrHeaderListSizeLimitViolation indicates that the header list size is larger
 	// than the limit set by peer.
-	ErrHeaderListSizeLimitViolation = errors.New("transport: trying to send header list size larger than the limit set by peer")
-	// statusRawProto is a function to get to the raw status proto wrapped in a
-	// status.Status without a proto.Clone().
-	statusRawProto = internal.StatusRawProto.(func(*status.Status) *spb.Status)
+	ErrHeaderListSizeLimitViolation = status.Error(codes.Internal, "transport: trying to send header list size larger than the limit set by peer")
 )
 
 // serverConnectionCounter counts the number of connections a server has seen
@@ -77,7 +73,6 @@ type http2Server struct {
 	writerDone  chan struct{} // sync point to enable testing.
 	remoteAddr  net.Addr
 	localAddr   net.Addr
-	maxStreamID uint32               // max stream ID ever seen
 	authInfo    credentials.AuthInfo // auth info about the connection
 	inTapHandle tap.ServerInHandle
 	framer      *framer
@@ -87,7 +82,7 @@ type http2Server struct {
 	// updates, reset streams, and various settings) to the controller.
 	controlBuf *controlBuffer
 	fc         *trInFlow
-	stats      stats.Handler
+	stats      []stats.Handler
 	// Keepalive and max-age parameters for the server.
 	kp keepalive.ServerParameters
 	// Keepalive enforcement policy.
@@ -106,11 +101,11 @@ type http2Server struct {
 
 	mu sync.Mutex // guard the following
 
-	// drainChan is initialized when drain(...) is called the first time.
+	// drainChan is initialized when Drain() is called the first time.
 	// After which the server writes out the first GoAway(with ID 2^31-1) frame.
 	// Then an independent goroutine will be launched to later send the second GoAway.
 	// During this time we don't want to write another first GoAway(with ID 2^31 -1) frame.
-	// Thus call to drain(...) will be a no-op if drainChan is already initialized since draining is
+	// Thus call to Drain() will be a no-op if drainChan is already initialized since draining is
 	// already underway.
 	drainChan     chan struct{}
 	state         transportState
@@ -122,16 +117,42 @@ type http2Server struct {
 	idle time.Time
 
 	// Fields below are for channelz metric collection.
-	channelzID int64 // channelz unique identification number
+	channelzID *channelz.Identifier
 	czData     *channelzData
 	bufferPool *bufferPool
 
 	connectionID uint64
+
+	// maxStreamMu guards the maximum stream ID
+	// This lock may not be taken if mu is already held.
+	maxStreamMu sync.Mutex
+	maxStreamID uint32 // max stream ID ever seen
 }
 
-// newHTTP2Server constructs a ServerTransport based on HTTP2. ConnectionError is
-// returned if something goes wrong.
-func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err error) {
+// NewServerTransport creates a http2 transport with conn and configuration
+// options from config.
+//
+// It returns a non-nil transport and a nil error on success. On failure, it
+// returns a nil transport and a non-nil error. For a special case where the
+// underlying conn gets closed before the client preface could be read, it
+// returns a nil transport and a nil error.
+func NewServerTransport(conn net.Conn, config *ServerConfig) (_ ServerTransport, err error) {
+	var authInfo credentials.AuthInfo
+	rawConn := conn
+	if config.Credentials != nil {
+		var err error
+		conn, authInfo, err = config.Credentials.ServerHandshake(rawConn)
+		if err != nil {
+			// ErrConnDispatched means that the connection was dispatched away
+			// from gRPC; those connections should be left open. io.EOF means
+			// the connection was closed before handshaking completed, which can
+			// happen naturally from probers. Return these errors directly.
+			if err == credentials.ErrConnDispatched || err == io.EOF {
+				return nil, err
+			}
+			return nil, connectionErrorf(false, err, "ServerHandshake(%q) failed: %v", rawConn.RemoteAddr(), err)
+		}
+	}
 	writeBufSize := config.WriteBufferSize
 	readBufSize := config.ReadBufferSize
 	maxHeaderListSize := defaultServerMaxHeaderListSize
@@ -210,18 +231,24 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 	if kp.Timeout == 0 {
 		kp.Timeout = defaultServerKeepaliveTimeout
 	}
+	if kp.Time != infinity {
+		if err = syscall.SetTCPUserTimeout(conn, kp.Timeout); err != nil {
+			return nil, connectionErrorf(false, err, "transport: failed to set TCP_USER_TIMEOUT: %v", err)
+		}
+	}
 	kep := config.KeepalivePolicy
 	if kep.MinTime == 0 {
 		kep.MinTime = defaultKeepalivePolicyMinTime
 	}
+
 	done := make(chan struct{})
 	t := &http2Server{
-		ctx:               context.Background(),
+		ctx:               setConnection(context.Background(), rawConn),
 		done:              done,
 		conn:              conn,
 		remoteAddr:        conn.RemoteAddr(),
 		localAddr:         conn.LocalAddr(),
-		authInfo:          config.AuthInfo,
+		authInfo:          authInfo,
 		framer:            framer,
 		readerDone:        make(chan struct{}),
 		writerDone:        make(chan struct{}),
@@ -230,7 +257,7 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 		fc:                &trInFlow{limit: uint32(icwz)},
 		state:             reachable,
 		activeStreams:     make(map[uint32]*Stream),
-		stats:             config.StatsHandler,
+		stats:             config.StatsHandlers,
 		kp:                kp,
 		idle:              time.Now(),
 		kep:               kep,
@@ -245,20 +272,20 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 			updateFlowControl: t.updateFlowControl,
 		}
 	}
-	if t.stats != nil {
-		t.ctx = t.stats.TagConn(t.ctx, &stats.ConnTagInfo{
+	for _, sh := range t.stats {
+		t.ctx = sh.TagConn(t.ctx, &stats.ConnTagInfo{
 			RemoteAddr: t.remoteAddr,
 			LocalAddr:  t.localAddr,
 		})
 		connBegin := &stats.ConnBegin{}
-		t.stats.HandleConn(t.ctx, connBegin)
+		sh.HandleConn(t.ctx, connBegin)
 	}
-	if channelz.IsOn() {
-		t.channelzID = channelz.RegisterNormalSocket(t, config.ChannelzParentID, fmt.Sprintf("%s -> %s", t.remoteAddr, t.localAddr))
+	t.channelzID, err = channelz.RegisterNormalSocket(t, config.ChannelzParentID, fmt.Sprintf("%s -> %s", t.remoteAddr, t.localAddr))
+	if err != nil {
+		return nil, err
 	}
 
 	t.connectionID = atomic.AddUint64(&serverConnectionCounter, 1)
-
 	t.framer.writer.Flush()
 
 	defer func() {
@@ -270,6 +297,14 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 	// Check the validity of client preface.
 	preface := make([]byte, len(clientPreface))
 	if _, err := io.ReadFull(t.conn, preface); err != nil {
+		// In deployments where a gRPC server runs behind a cloud load balancer
+		// which performs regular TCP level health checks, the connection is
+		// closed immediately by the latter.  Returning io.EOF here allows the
+		// grpc server implementation to recognize this scenario and suppress
+		// logging to reduce spam.
+		if err == io.EOF {
+			return nil, io.EOF
+		}
 		return nil, connectionErrorf(false, err, "transport: http2Server.HandleStreams failed to receive the preface from client: %v", err)
 	}
 	if !bytes.Equal(preface, clientPreface) {
@@ -294,9 +329,12 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 		t.loopy = newLoopyWriter(serverSide, t.framer, t.controlBuf, t.bdpEst)
 		t.loopy.ssGoAwayHandler = t.outgoingGoAwayHandler
 		if err := t.loopy.run(); err != nil {
-			errorf("transport: loopyWriter.run returning. Err: %v", err)
+			if logger.V(logLevel) {
+				logger.Errorf("transport: loopyWriter.run returning. Err: %v", err)
+			}
 		}
 		t.conn.Close()
+		t.controlBuf.finish()
 		close(t.writerDone)
 	}()
 	go t.keepalive()
@@ -305,38 +343,145 @@ func newHTTP2Server(conn net.Conn, config *ServerConfig) (_ ServerTransport, err
 
 // operateHeader takes action on the decoded headers.
 func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(*Stream), traceCtx func(context.Context, string) context.Context) (fatal bool) {
+	// Acquire max stream ID lock for entire duration
+	t.maxStreamMu.Lock()
+	defer t.maxStreamMu.Unlock()
+
 	streamID := frame.Header().StreamID
-	state := &decodeState{
-		serverSide: true,
-	}
-	if err := state.decodeHeader(frame); err != nil {
-		if se, ok := status.FromError(err); ok {
-			t.controlBuf.put(&cleanupStream{
-				streamID: streamID,
-				rst:      true,
-				rstCode:  statusCodeConvTab[se.Code()],
-				onWrite:  func() {},
-			})
-		}
+
+	// frame.Truncated is set to true when framer detects that the current header
+	// list size hits MaxHeaderListSize limit.
+	if frame.Truncated {
+		t.controlBuf.put(&cleanupStream{
+			streamID: streamID,
+			rst:      true,
+			rstCode:  http2.ErrCodeFrameSize,
+			onWrite:  func() {},
+		})
 		return false
 	}
 
+	if streamID%2 != 1 || streamID <= t.maxStreamID {
+		// illegal gRPC stream id.
+		if logger.V(logLevel) {
+			logger.Errorf("transport: http2Server.HandleStreams received an illegal stream id: %v", streamID)
+		}
+		return true
+	}
+	t.maxStreamID = streamID
+
 	buf := newRecvBuffer()
 	s := &Stream{
-		id:             streamID,
-		st:             t,
-		buf:            buf,
-		fc:             &inFlow{limit: uint32(t.initialWindowSize)},
-		recvCompress:   state.data.encoding,
-		method:         state.data.method,
-		contentSubtype: state.data.contentSubtype,
+		id:  streamID,
+		st:  t,
+		buf: buf,
+		fc:  &inFlow{limit: uint32(t.initialWindowSize)},
 	}
+	var (
+		// If a gRPC Response-Headers has already been received, then it means
+		// that the peer is speaking gRPC and we are in gRPC mode.
+		isGRPC     = false
+		mdata      = make(map[string][]string)
+		httpMethod string
+		// headerError is set if an error is encountered while parsing the headers
+		headerError bool
+
+		timeoutSet bool
+		timeout    time.Duration
+	)
+
+	for _, hf := range frame.Fields {
+		switch hf.Name {
+		case "content-type":
+			contentSubtype, validContentType := grpcutil.ContentSubtype(hf.Value)
+			if !validContentType {
+				break
+			}
+			mdata[hf.Name] = append(mdata[hf.Name], hf.Value)
+			s.contentSubtype = contentSubtype
+			isGRPC = true
+		case "grpc-encoding":
+			s.recvCompress = hf.Value
+		case ":method":
+			httpMethod = hf.Value
+		case ":path":
+			s.method = hf.Value
+		case "grpc-timeout":
+			timeoutSet = true
+			var err error
+			if timeout, err = decodeTimeout(hf.Value); err != nil {
+				headerError = true
+			}
+		// "Transports must consider requests containing the Connection header
+		// as malformed." - A41
+		case "connection":
+			if logger.V(logLevel) {
+				logger.Errorf("transport: http2Server.operateHeaders parsed a :connection header which makes a request malformed as per the HTTP/2 spec")
+			}
+			headerError = true
+		default:
+			if isReservedHeader(hf.Name) && !isWhitelistedHeader(hf.Name) {
+				break
+			}
+			v, err := decodeMetadataHeader(hf.Name, hf.Value)
+			if err != nil {
+				headerError = true
+				logger.Warningf("Failed to decode metadata header (%q, %q): %v", hf.Name, hf.Value, err)
+				break
+			}
+			mdata[hf.Name] = append(mdata[hf.Name], v)
+		}
+	}
+
+	// "If multiple Host headers or multiple :authority headers are present, the
+	// request must be rejected with an HTTP status code 400 as required by Host
+	// validation in RFC 7230 §5.4, gRPC status code INTERNAL, or RST_STREAM
+	// with HTTP/2 error code PROTOCOL_ERROR." - A41. Since this is a HTTP/2
+	// error, this takes precedence over a client not speaking gRPC.
+	if len(mdata[":authority"]) > 1 || len(mdata["host"]) > 1 {
+		errMsg := fmt.Sprintf("num values of :authority: %v, num values of host: %v, both must only have 1 value as per HTTP/2 spec", len(mdata[":authority"]), len(mdata["host"]))
+		if logger.V(logLevel) {
+			logger.Errorf("transport: %v", errMsg)
+		}
+		t.controlBuf.put(&earlyAbortStream{
+			httpStatus:     400,
+			streamID:       streamID,
+			contentSubtype: s.contentSubtype,
+			status:         status.New(codes.Internal, errMsg),
+			rst:            !frame.StreamEnded(),
+		})
+		return false
+	}
+
+	if !isGRPC || headerError {
+		t.controlBuf.put(&cleanupStream{
+			streamID: streamID,
+			rst:      true,
+			rstCode:  http2.ErrCodeProtocol,
+			onWrite:  func() {},
+		})
+		return false
+	}
+
+	// "If :authority is missing, Host must be renamed to :authority." - A41
+	if len(mdata[":authority"]) == 0 {
+		// No-op if host isn't present, no eventual :authority header is a valid
+		// RPC.
+		if host, ok := mdata["host"]; ok {
+			mdata[":authority"] = host
+			delete(mdata, "host")
+		}
+	} else {
+		// "If :authority is present, Host must be discarded" - A41
+		delete(mdata, "host")
+	}
+
 	if frame.StreamEnded() {
 		// s is just created by the caller. No lock needed.
 		s.state = streamReadDone
 	}
-	if state.data.timeoutSet {
-		s.ctx, s.cancel = context.WithTimeout(t.ctx, state.data.timeout)
+	if timeoutSet {
+		s.ctx, s.cancel = context.WithTimeout(t.ctx, timeout)
 	} else {
 		s.ctx, s.cancel = context.WithCancel(t.ctx)
 	}
@@ -349,31 +494,13 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 	}
 	s.ctx = peer.NewContext(s.ctx, pr)
 	// Attach the received metadata to the context.
-	if len(state.data.mdata) > 0 {
-		s.ctx = metadata.NewIncomingContext(s.ctx, state.data.mdata)
-	}
-	if state.data.statsTags != nil {
-		s.ctx = stats.SetIncomingTags(s.ctx, state.data.statsTags)
-	}
-	if state.data.statsTrace != nil {
-		s.ctx = stats.SetIncomingTrace(s.ctx, state.data.statsTrace)
-	}
-	if t.inTapHandle != nil {
-		var err error
-		info := &tap.Info{
-			FullMethodName: state.data.method,
+	if len(mdata) > 0 {
+		s.ctx = metadata.NewIncomingContext(s.ctx, mdata)
+		if statsTags := mdata["grpc-tags-bin"]; len(statsTags) > 0 {
+			s.ctx = stats.SetIncomingTags(s.ctx, []byte(statsTags[len(statsTags)-1]))
 		}
-		s.ctx, err = t.inTapHandle(s.ctx, info)
-		if err != nil {
-			warningf("transport: http2Server.operateHeaders got an error from InTapHandle: %v", err)
-			t.controlBuf.put(&cleanupStream{
-				streamID: s.id,
-				rst:      true,
-				rstCode:  http2.ErrCodeRefusedStream,
-				onWrite:  func() {},
-			})
-			s.cancel()
-			return false
+		if statsTrace := mdata["grpc-trace-bin"]; len(statsTrace) > 0 {
+			s.ctx = stats.SetIncomingTrace(s.ctx, []byte(statsTrace[len(statsTrace)-1]))
 		}
 	}
 	t.mu.Lock()
@@ -393,14 +520,43 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 		s.cancel()
 		return false
 	}
-	if streamID%2 != 1 || streamID <= t.maxStreamID {
+	if httpMethod != http.MethodPost {
 		t.mu.Unlock()
-		// illegal gRPC stream id.
-		errorf("transport: http2Server.HandleStreams received an illegal stream id: %v", streamID)
+		errMsg := fmt.Sprintf("http2Server.operateHeaders parsed a :method field: %v which should be POST", httpMethod)
+		if logger.V(logLevel) {
+			logger.Infof("transport: %v", errMsg)
+		}
+		t.controlBuf.put(&earlyAbortStream{
+			httpStatus:     405,
+			streamID:       streamID,
+			contentSubtype: s.contentSubtype,
+			status:         status.New(codes.Internal, errMsg),
+			rst:            !frame.StreamEnded(),
+		})
 		s.cancel()
-		return true
+		return false
+	}
+	if t.inTapHandle != nil {
+		var err error
+		if s.ctx, err = t.inTapHandle(s.ctx, &tap.Info{FullMethodName: s.method}); err != nil {
+			t.mu.Unlock()
+			if logger.V(logLevel) {
+				logger.Infof("transport: http2Server.operateHeaders got an error from InTapHandle: %v", err)
+			}
+			stat, ok := status.FromError(err)
+			if !ok {
+				stat = status.New(codes.PermissionDenied, err.Error())
+			}
+			t.controlBuf.put(&earlyAbortStream{
+				httpStatus:     200,
+				streamID:       s.id,
+				contentSubtype: s.contentSubtype,
+				status:         stat,
+				rst:            !frame.StreamEnded(),
+			})
+			return false
+		}
 	}
-	t.maxStreamID = streamID
 	t.activeStreams[streamID] = s
 	if len(t.activeStreams) == 1 {
 		t.idle = time.Time{}
@@ -414,17 +570,17 @@ func (t *http2Server) operateHeaders(frame *http2.MetaHeadersFrame, handle func(
 		t.adjustWindow(s, uint32(n))
 	}
 	s.ctx = traceCtx(s.ctx, s.method)
-	if t.stats != nil {
-		s.ctx = t.stats.TagRPC(s.ctx, &stats.RPCTagInfo{FullMethodName: s.method})
+	for _, sh := range t.stats {
+		s.ctx = sh.TagRPC(s.ctx, &stats.RPCTagInfo{FullMethodName: s.method})
 		inHeader := &stats.InHeader{
 			FullMethod:  s.method,
 			RemoteAddr:  t.remoteAddr,
 			LocalAddr:   t.localAddr,
 			Compression: s.recvCompress,
 			WireLength:  int(frame.Header().Length),
-			Header:      metadata.MD(state.data.mdata).Copy(),
+			Header:      metadata.MD(mdata).Copy(),
 		}
-		t.stats.HandleRPC(s.ctx, inHeader)
+		sh.HandleRPC(s.ctx, inHeader)
 	}
 	s.ctxDone = s.ctx.Done()
 	s.wq = newWriteQuota(defaultWriteQuota, s.ctxDone)
@@ -459,7 +615,9 @@ func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.
 		atomic.StoreInt64(&t.lastRead, time.Now().UnixNano())
 		if err != nil {
 			if se, ok := err.(http2.StreamError); ok {
-				warningf("transport: http2Server.HandleStreams encountered http2.StreamError: %v", se)
+				if logger.V(logLevel) {
+					logger.Warningf("transport: http2Server.HandleStreams encountered http2.StreamError: %v", se)
+				}
 				t.mu.Lock()
 				s := t.activeStreams[se.StreamID]
 				t.mu.Unlock()
@@ -479,7 +637,9 @@ func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.
 				t.Close()
 				return
 			}
-			warningf("transport: http2Server.HandleStreams failed to read frame: %v", err)
+			if logger.V(logLevel) {
+				logger.Warningf("transport: http2Server.HandleStreams failed to read frame: %v", err)
+			}
 			t.Close()
 			return
 		}
@@ -502,7 +662,9 @@ func (t *http2Server) HandleStreams(handle func(*Stream), traceCtx func(context.
 		case *http2.GoAwayFrame:
 			// TODO: Handle GoAway from the client appropriately.
 		default:
-			errorf("transport: http2Server.HandleStreams found unhandled frame type %v.", frame)
+			if logger.V(logLevel) {
+				logger.Errorf("transport: http2Server.HandleStreams found unhandled frame type %v.", frame)
+			}
 		}
 	}
 }
@@ -604,6 +766,10 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 	if !ok {
 		return
 	}
+	if s.getState() == streamReadDone {
+		t.closeStream(s, true, http2.ErrCodeStreamClosed, false)
+		return
+	}
 	if size > 0 {
 		if err := s.fc.onData(size); err != nil {
 			t.closeStream(s, true, http2.ErrCodeFlowControl, false)
@@ -624,7 +790,7 @@ func (t *http2Server) handleData(f *http2.DataFrame) {
 			s.write(recvMsg{buffer: buffer})
 		}
 	}
-	if f.Header().Flags.Has(http2.FlagDataEndStream) {
+	if f.StreamEnded() {
 		// Received the end of stream from the client.
 		s.compareAndSwapState(streamActive, streamReadDone)
 		s.write(recvMsg{err: io.EOF})
@@ -724,7 +890,9 @@ func (t *http2Server) handlePing(f *http2.PingFrame) {
 
 	if t.pingStrikes > maxPingStrikes {
 		// Send goaway and close the connection.
-		errorf("transport: Got too many pings from the client, closing the connection.")
+		if logger.V(logLevel) {
+			logger.Errorf("transport: Got too many pings from the client, closing the connection.")
+		}
 		t.controlBuf.put(&goAway{code: http2.ErrCodeEnhanceYourCalm, debugData: []byte("too_many_pings"), closeConn: true})
 	}
 }
@@ -757,18 +925,34 @@ func (t *http2Server) checkForHeaderListSize(it interface{}) bool {
 	var sz int64
 	for _, f := range hdrFrame.hf {
 		if sz += int64(f.Size()); sz > int64(*t.maxSendHeaderListSize) {
-			errorf("header list size to send violates the maximum size (%d bytes) set by client", *t.maxSendHeaderListSize)
+			if logger.V(logLevel) {
+				logger.Errorf("header list size to send violates the maximum size (%d bytes) set by client", *t.maxSendHeaderListSize)
+			}
 			return false
 		}
 	}
 	return true
 }
 
+func (t *http2Server) streamContextErr(s *Stream) error {
+	select {
+	case <-t.done:
+		return ErrConnClosing
+	default:
+	}
+	return ContextErr(s.ctx.Err())
+}
+
 // WriteHeader sends the header metadata md back to the client.
 func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error {
-	if s.updateHeaderSent() || s.getState() == streamDone {
+	if s.updateHeaderSent() {
 		return ErrIllegalHeaderWrite
 	}
+
+	if s.getState() == streamDone {
+		return t.streamContextErr(s)
+	}
+
 	s.hdrMu.Lock()
 	if md.Len() > 0 {
 		if s.header.Len() > 0 {
@@ -779,7 +963,7 @@ func (t *http2Server) WriteHeader(s *Stream, md metadata.MD) error {
 	}
 	if err := t.writeHeaderLocked(s); err != nil {
 		s.hdrMu.Unlock()
-		return err
+		return status.Convert(err).Err()
 	}
 	s.hdrMu.Unlock()
 	return nil
@@ -794,7 +978,7 @@ func (t *http2Server) writeHeaderLocked(s *Stream) error {
 	// first and create a slice of that exact size.
 	headerFields := make([]hpack.HeaderField, 0, 2) // at least :status, content-type will be there if none else.
 	headerFields = append(headerFields, hpack.HeaderField{Name: ":status", Value: "200"})
-	headerFields = append(headerFields, hpack.HeaderField{Name: "content-type", Value: contentType(s.contentSubtype)})
+	headerFields = append(headerFields, hpack.HeaderField{Name: "content-type", Value: grpcutil.ContentType(s.contentSubtype)})
 	if s.sendCompress != "" {
 		headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-encoding", Value: s.sendCompress})
 	}
@@ -812,13 +996,14 @@ func (t *http2Server) writeHeaderLocked(s *Stream) error {
 		t.closeStream(s, true, http2.ErrCodeInternal, false)
 		return ErrHeaderListSizeLimitViolation
 	}
-	if t.stats != nil {
-		// Note: WireLength is not set in outHeader.
-		// TODO(mmukhi): Revisit this later, if needed.
+	for _, sh := range t.stats {
+		// Note: Headers are compressed with hpack after this call returns.
+		// No WireLength field is set here.
 		outHeader := &stats.OutHeader{
-			Header: s.header.Copy(),
+			Header:      s.header.Copy(),
+			Compression: s.sendCompress,
 		}
-		t.stats.HandleRPC(s.Context(), outHeader)
+		sh.HandleRPC(s.Context(), outHeader)
 	}
 	return nil
 }
@@ -843,17 +1028,17 @@ func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 			}
 		} else { // Send a trailer only response.
 			headerFields = append(headerFields, hpack.HeaderField{Name: ":status", Value: "200"})
-			headerFields = append(headerFields, hpack.HeaderField{Name: "content-type", Value: contentType(s.contentSubtype)})
+			headerFields = append(headerFields, hpack.HeaderField{Name: "content-type", Value: grpcutil.ContentType(s.contentSubtype)})
 		}
 	}
 	headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-status", Value: strconv.Itoa(int(st.Code()))})
 	headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-message", Value: encodeGrpcMessage(st.Message())})
 
-	if p := statusRawProto(st); p != nil && len(p.Details) > 0 {
+	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.
-			grpclog.Errorf("transport: failed to marshal rpc status: %v, error: %v", p, err)
+			logger.Errorf("transport: failed to marshal rpc status: %v, error: %v", p, err)
 		} else {
 			headerFields = append(headerFields, hpack.HeaderField{Name: "grpc-status-details-bin", Value: encodeBinHeader(stBytes)})
 		}
@@ -879,8 +1064,10 @@ func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 	// Send a RST_STREAM after the trailers if the client has not already half-closed.
 	rst := s.getState() == streamActive
 	t.finishStream(s, rst, http2.ErrCodeNo, trailingHeader, true)
-	if t.stats != nil {
-		t.stats.HandleRPC(s.Context(), &stats.OutTrailer{
+	for _, sh := range t.stats {
+		// Note: The trailer fields are compressed with hpack after this call returns.
+		// No WireLength field is set here.
+		sh.HandleRPC(s.Context(), &stats.OutTrailer{
 			Trailer: s.trailer.Copy(),
 		})
 	}
@@ -892,32 +1079,14 @@ func (t *http2Server) WriteStatus(s *Stream, st *status.Status) error {
 func (t *http2Server) Write(s *Stream, hdr []byte, data []byte, opts *Options) error {
 	if !s.isHeaderSent() { // Headers haven't been written yet.
 		if err := t.WriteHeader(s, nil); err != nil {
-			if _, ok := err.(ConnectionError); ok {
-				return err
-			}
-			// TODO(mmukhi, dfawley): Make sure this is the right code to return.
-			return status.Errorf(codes.Internal, "transport: %v", err)
+			return err
 		}
 	} else {
 		// Writing headers checks for this condition.
 		if s.getState() == streamDone {
-			// TODO(mmukhi, dfawley): Should the server write also return io.EOF?
-			s.cancel()
-			select {
-			case <-t.done:
-				return ErrConnClosing
-			default:
-			}
-			return ContextErr(s.ctx.Err())
+			return t.streamContextErr(s)
 		}
 	}
-	// Add some data to header frame so that we can equally distribute bytes across frames.
-	emptyLen := http2MaxFrameLen - len(hdr)
-	if emptyLen > len(data) {
-		emptyLen = len(data)
-	}
-	hdr = append(hdr, data[:emptyLen]...)
-	data = data[emptyLen:]
 	df := &dataFrame{
 		streamID:    s.id,
 		h:           hdr,
@@ -925,12 +1094,7 @@ func (t *http2Server) Write(s *Stream, hdr []byte, data []byte, opts *Options) e
 		onEachWrite: t.setResetPingStrikes,
 	}
 	if err := s.wq.get(int32(len(hdr) + len(data))); err != nil {
-		select {
-		case <-t.done:
-			return ErrConnClosing
-		default:
-		}
-		return ContextErr(s.ctx.Err())
+		return t.streamContextErr(s)
 	}
 	return t.controlBuf.put(df)
 }
@@ -979,17 +1143,19 @@ func (t *http2Server) keepalive() {
 			if val <= 0 {
 				// The connection has been idle for a duration of keepalive.MaxConnectionIdle or more.
 				// Gracefully close the connection.
-				t.drain(http2.ErrCodeNo, []byte{})
+				t.Drain()
 				return
 			}
 			idleTimer.Reset(val)
 		case <-ageTimer.C:
-			t.drain(http2.ErrCodeNo, []byte{})
+			t.Drain()
 			ageTimer.Reset(t.kp.MaxConnectionAgeGrace)
 			select {
 			case <-ageTimer.C:
 				// Close the connection after grace period.
-				infof("transport: closing server transport due to maximum connection age.")
+				if logger.V(logLevel) {
+					logger.Infof("transport: closing server transport due to maximum connection age.")
+				}
 				t.Close()
 			case <-t.done:
 			}
@@ -1006,7 +1172,9 @@ func (t *http2Server) keepalive() {
 				continue
 			}
 			if outstandingPing && kpTimeoutLeft <= 0 {
-				infof("transport: closing server transport due to idleness.")
+				if logger.V(logLevel) {
+					logger.Infof("transport: closing server transport due to idleness.")
+				}
 				t.Close()
 				return
 			}
@@ -1034,11 +1202,11 @@ func (t *http2Server) keepalive() {
 // Close starts shutting down the http2Server transport.
 // TODO(zhaoq): Now the destruction is not blocked on any pending streams. This
 // could cause some resource issue. Revisit this later.
-func (t *http2Server) Close() error {
+func (t *http2Server) Close() {
 	t.mu.Lock()
 	if t.state == closing {
 		t.mu.Unlock()
-		return errors.New("transport: Close() was already called")
+		return
 	}
 	t.state = closing
 	streams := t.activeStreams
@@ -1046,27 +1214,22 @@ func (t *http2Server) Close() error {
 	t.mu.Unlock()
 	t.controlBuf.finish()
 	close(t.done)
-	err := t.conn.Close()
-	if channelz.IsOn() {
-		channelz.RemoveEntry(t.channelzID)
+	if err := t.conn.Close(); err != nil && logger.V(logLevel) {
+		logger.Infof("transport: error closing conn during Close: %v", err)
 	}
+	channelz.RemoveEntry(t.channelzID)
 	// Cancel all active streams.
 	for _, s := range streams {
 		s.cancel()
 	}
-	if t.stats != nil {
+	for _, sh := range t.stats {
 		connEnd := &stats.ConnEnd{}
-		t.stats.HandleConn(t.ctx, connEnd)
+		sh.HandleConn(t.ctx, connEnd)
 	}
-	return err
 }
 
 // deleteStream deletes the stream s from transport's active streams.
 func (t *http2Server) deleteStream(s *Stream, eosReceived bool) {
-	// In case stream sending and receiving are invoked in separate
-	// goroutines (e.g., bi-directional streaming), cancel needs to be
-	// called to interrupt the potential blocking on other goroutines.
-	s.cancel()
 
 	t.mu.Lock()
 	if _, ok := t.activeStreams[s.id]; ok {
@@ -1088,6 +1251,11 @@ func (t *http2Server) deleteStream(s *Stream, eosReceived bool) {
 
 // finishStream closes the stream and puts the trailing headerFrame into controlbuf.
 func (t *http2Server) finishStream(s *Stream, rst bool, rstCode http2.ErrCode, hdr *headerFrame, eosReceived bool) {
+	// In case stream sending and receiving are invoked in separate
+	// goroutines (e.g., bi-directional streaming), cancel needs to be
+	// called to interrupt the potential blocking on other goroutines.
+	s.cancel()
+
 	oldState := s.swapState(streamDone)
 	if oldState == streamDone {
 		// If the stream was already done, return.
@@ -1107,6 +1275,11 @@ func (t *http2Server) finishStream(s *Stream, rst bool, rstCode http2.ErrCode, h
 
 // closeStream clears the footprint of a stream when the stream is not needed any more.
 func (t *http2Server) closeStream(s *Stream, rst bool, rstCode http2.ErrCode, eosReceived bool) {
+	// In case stream sending and receiving are invoked in separate
+	// goroutines (e.g., bi-directional streaming), cancel needs to be
+	// called to interrupt the potential blocking on other goroutines.
+	s.cancel()
+
 	s.swapState(streamDone)
 	t.deleteStream(s, eosReceived)
 
@@ -1123,17 +1296,13 @@ func (t *http2Server) RemoteAddr() net.Addr {
 }
 
 func (t *http2Server) Drain() {
-	t.drain(http2.ErrCodeNo, []byte{})
-}
-
-func (t *http2Server) drain(code http2.ErrCode, debugData []byte) {
 	t.mu.Lock()
 	defer t.mu.Unlock()
 	if t.drainChan != nil {
 		return
 	}
 	t.drainChan = make(chan struct{})
-	t.controlBuf.put(&goAway{code: code, debugData: debugData, headsUp: true})
+	t.controlBuf.put(&goAway{code: http2.ErrCodeNo, debugData: []byte{}, headsUp: true})
 }
 
 var goAwayPing = &ping{data: [8]byte{1, 6, 1, 8, 0, 3, 3, 9}}
@@ -1141,20 +1310,23 @@ var goAwayPing = &ping{data: [8]byte{1, 6, 1, 8, 0, 3, 3, 9}}
 // Handles outgoing GoAway and returns true if loopy needs to put itself
 // in draining mode.
 func (t *http2Server) outgoingGoAwayHandler(g *goAway) (bool, error) {
+	t.maxStreamMu.Lock()
 	t.mu.Lock()
 	if t.state == closing { // TODO(mmukhi): This seems unnecessary.
 		t.mu.Unlock()
+		t.maxStreamMu.Unlock()
 		// The transport is closing.
 		return false, ErrConnClosing
 	}
-	sid := t.maxStreamID
 	if !g.headsUp {
 		// Stop accepting more streams now.
 		t.state = draining
+		sid := t.maxStreamID
 		if len(t.activeStreams) == 0 {
 			g.closeConn = true
 		}
 		t.mu.Unlock()
+		t.maxStreamMu.Unlock()
 		if err := t.framer.fr.WriteGoAway(sid, g.code, g.debugData); err != nil {
 			return false, err
 		}
@@ -1167,6 +1339,7 @@ func (t *http2Server) outgoingGoAwayHandler(g *goAway) (bool, error) {
 		return true, nil
 	}
 	t.mu.Unlock()
+	t.maxStreamMu.Unlock()
 	// For a graceful close, send out a GoAway with stream ID of MaxUInt32,
 	// Follow that with a ping and wait for the ack to come back or a timer
 	// to expire. During this time accept new streams since they might have
@@ -1251,3 +1424,18 @@ func getJitter(v time.Duration) time.Duration {
 	j := grpcrand.Int63n(2*r) - r
 	return time.Duration(j)
 }
+
+type connectionKey struct{}
+
+// GetConnection gets the connection from the context.
+func GetConnection(ctx context.Context) net.Conn {
+	conn, _ := ctx.Value(connectionKey{}).(net.Conn)
+	return conn
+}
+
+// SetConnection adds the connection to the context to be able to get
+// information about the destination ip and port for an incoming RPC. This also
+// allows any unary or streaming interceptors to see the connection.
+func setConnection(ctx context.Context, conn net.Conn) context.Context {
+	return context.WithValue(ctx, connectionKey{}, conn)
+}

vendor/google.golang.org/grpc/internal/transport/http_util.go

@@ -27,6 +27,7 @@ import (
 	"math"
 	"net"
 	"net/http"
+	"net/url"
 	"strconv"
 	"strings"
 	"time"
@@ -37,6 +38,7 @@ import (
 	"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/status"
 )
 
@@ -50,7 +52,7 @@ const (
 	// "proto" as a suffix after "+" or ";".  See
 	// https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests
 	// for more details.
-	baseContentType = "application/grpc"
+
 )
 
 var (
@@ -71,13 +73,6 @@ var (
 		http2.ErrCodeInadequateSecurity: codes.PermissionDenied,
 		http2.ErrCodeHTTP11Required:     codes.Internal,
 	}
-	statusCodeConvTab = map[codes.Code]http2.ErrCode{
-		codes.Internal:          http2.ErrCodeInternal,
-		codes.Canceled:          http2.ErrCodeCancel,
-		codes.Unavailable:       http2.ErrCodeRefusedStream,
-		codes.ResourceExhausted: http2.ErrCodeEnhanceYourCalm,
-		codes.PermissionDenied:  http2.ErrCodeInadequateSecurity,
-	}
 	// HTTPStatusConvTab is the HTTP status code to gRPC error code conversion table.
 	HTTPStatusConvTab = map[int]codes.Code{
 		// 400 Bad Request - INTERNAL.
@@ -97,54 +92,9 @@ var (
 		// 504 Gateway timeout - UNAVAILABLE.
 		http.StatusGatewayTimeout: codes.Unavailable,
 	}
+	logger = grpclog.Component("transport")
 )
 
-type parsedHeaderData struct {
-	encoding string
-	// statusGen caches the stream status received from the trailer the server
-	// sent.  Client side only.  Do not access directly.  After all trailers are
-	// 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 *int
-	rawStatusMsg  string
-	httpStatus    *int
-	// Server side only fields.
-	timeoutSet bool
-	timeout    time.Duration
-	method     string
-	// key-value metadata map from the peer.
-	mdata          map[string][]string
-	statsTags      []byte
-	statsTrace     []byte
-	contentSubtype string
-
-	// isGRPC field indicates whether the peer is speaking gRPC (otherwise HTTP).
-	//
-	// We are in gRPC mode (peer speaking gRPC) if:
-	// 	* We are client side and have already received a HEADER frame that indicates gRPC peer.
-	//  * The header contains valid  a content-type, i.e. a string starts with "application/grpc"
-	// And we should handle error specific to gRPC.
-	//
-	// Otherwise (i.e. a content-type string starts without "application/grpc", or does not exist), we
-	// are in HTTP fallback mode, and should handle error specific to HTTP.
-	isGRPC         bool
-	grpcErr        error
-	httpErr        error
-	contentTypeErr string
-}
-
-// decodeState configures decoding criteria and records the decoded data.
-type decodeState struct {
-	// whether decoding on server side or not
-	serverSide bool
-
-	// Records the states during HPACK decoding. It will be filled with info parsed from HTTP HEADERS
-	// frame once decodeHeader function has been invoked and returned.
-	data parsedHeaderData
-}
-
 // isReservedHeader checks whether hdr belongs to HTTP2 headers
 // reserved by gRPC protocol. Any other headers are classified as the
 // user-specified metadata.
@@ -182,54 +132,6 @@ func isWhitelistedHeader(hdr string) bool {
 	}
 }
 
-// contentSubtype returns the content-subtype for the given content-type.  The
-// given content-type must be a valid content-type that starts with
-// "application/grpc". A content-subtype will follow "application/grpc" after a
-// "+" or ";". See
-// https://github.com/grpc/grpc/blob/master/doc/PROTOCOL-HTTP2.md#requests for
-// more details.
-//
-// If contentType is not a valid content-type for gRPC, the boolean
-// will be false, otherwise true. If content-type == "application/grpc",
-// "application/grpc+", or "application/grpc;", the boolean will be true,
-// but no content-subtype will be returned.
-//
-// contentType is assumed to be lowercase already.
-func contentSubtype(contentType string) (string, bool) {
-	if contentType == baseContentType {
-		return "", true
-	}
-	if !strings.HasPrefix(contentType, baseContentType) {
-		return "", false
-	}
-	// guaranteed since != baseContentType and has baseContentType prefix
-	switch contentType[len(baseContentType)] {
-	case '+', ';':
-		// this will return true for "application/grpc+" or "application/grpc;"
-		// which the previous validContentType function tested to be valid, so we
-		// just say that no content-subtype is specified in this case
-		return contentType[len(baseContentType)+1:], true
-	default:
-		return "", false
-	}
-}
-
-// contentSubtype is assumed to be lowercase
-func contentType(contentSubtype string) string {
-	if contentSubtype == "" {
-		return baseContentType
-	}
-	return baseContentType + "+" + contentSubtype
-}
-
-func (d *decodeState) status() *status.Status {
-	if d.data.statusGen == nil {
-		// No status-details were provided; generate status using code/msg.
-		d.data.statusGen = status.New(codes.Code(int32(*(d.data.rawStatusCode))), d.data.rawStatusMsg)
-	}
-	return d.data.statusGen
-}
-
 const binHdrSuffix = "-bin"
 
 func encodeBinHeader(v []byte) string {
@@ -259,164 +161,16 @@ func decodeMetadataHeader(k, v string) (string, error) {
 	return v, nil
 }
 
-func (d *decodeState) decodeHeader(frame *http2.MetaHeadersFrame) error {
-	// frame.Truncated is set to true when framer detects that the current header
-	// list size hits MaxHeaderListSize limit.
-	if frame.Truncated {
-		return status.Error(codes.Internal, "peer header list size exceeded limit")
+func decodeGRPCStatusDetails(rawDetails string) (*status.Status, error) {
+	v, err := decodeBinHeader(rawDetails)
+	if err != nil {
+		return nil, err
 	}
-
-	for _, hf := range frame.Fields {
-		d.processHeaderField(hf)
-	}
-
-	if d.data.isGRPC {
-		if d.data.grpcErr != nil {
-			return d.data.grpcErr
-		}
-		if d.serverSide {
-			return nil
-		}
-		if d.data.rawStatusCode == nil && d.data.statusGen == nil {
-			// gRPC status doesn't exist.
-			// Set rawStatusCode to be unknown and return nil error.
-			// So that, if the stream has ended this Unknown status
-			// will be propagated to the user.
-			// Otherwise, it will be ignored. In which case, status from
-			// a later trailer, that has StreamEnded flag set, is propagated.
-			code := int(codes.Unknown)
-			d.data.rawStatusCode = &code
-		}
-		return nil
-	}
-
-	// HTTP fallback mode
-	if d.data.httpErr != nil {
-		return d.data.httpErr
-	}
-
-	var (
-		code = codes.Internal // when header does not include HTTP status, return INTERNAL
-		ok   bool
-	)
-
-	if d.data.httpStatus != nil {
-		code, ok = HTTPStatusConvTab[*(d.data.httpStatus)]
-		if !ok {
-			code = codes.Unknown
-		}
-	}
-
-	return status.Error(code, d.constructHTTPErrMsg())
-}
-
-// constructErrMsg constructs error message to be returned in HTTP fallback mode.
-// Format: HTTP status code and its corresponding message + content-type error message.
-func (d *decodeState) constructHTTPErrMsg() string {
-	var errMsgs []string
-
-	if d.data.httpStatus == nil {
-		errMsgs = append(errMsgs, "malformed header: missing HTTP status")
-	} else {
-		errMsgs = append(errMsgs, fmt.Sprintf("%s: HTTP status code %d", http.StatusText(*(d.data.httpStatus)), *d.data.httpStatus))
-	}
-
-	if d.data.contentTypeErr == "" {
-		errMsgs = append(errMsgs, "transport: missing content-type field")
-	} else {
-		errMsgs = append(errMsgs, d.data.contentTypeErr)
-	}
-
-	return strings.Join(errMsgs, "; ")
-}
-
-func (d *decodeState) addMetadata(k, v string) {
-	if d.data.mdata == nil {
-		d.data.mdata = make(map[string][]string)
-	}
-	d.data.mdata[k] = append(d.data.mdata[k], v)
-}
-
-func (d *decodeState) processHeaderField(f hpack.HeaderField) {
-	switch f.Name {
-	case "content-type":
-		contentSubtype, validContentType := contentSubtype(f.Value)
-		if !validContentType {
-			d.data.contentTypeErr = fmt.Sprintf("transport: received the unexpected content-type %q", f.Value)
-			return
-		}
-		d.data.contentSubtype = contentSubtype
-		// TODO: do we want to propagate the whole content-type in the metadata,
-		// or come up with a way to just propagate the content-subtype if it was set?
-		// ie {"content-type": "application/grpc+proto"} or {"content-subtype": "proto"}
-		// in the metadata?
-		d.addMetadata(f.Name, f.Value)
-		d.data.isGRPC = true
-	case "grpc-encoding":
-		d.data.encoding = f.Value
-	case "grpc-status":
-		code, err := strconv.Atoi(f.Value)
-		if err != nil {
-			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-status: %v", err)
-			return
-		}
-		d.data.rawStatusCode = &code
-	case "grpc-message":
-		d.data.rawStatusMsg = decodeGrpcMessage(f.Value)
-	case "grpc-status-details-bin":
-		v, err := decodeBinHeader(f.Value)
-		if err != nil {
-			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
-			return
-		}
-		s := &spb.Status{}
-		if err := proto.Unmarshal(v, s); err != nil {
-			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-status-details-bin: %v", err)
-			return
-		}
-		d.data.statusGen = status.FromProto(s)
-	case "grpc-timeout":
-		d.data.timeoutSet = true
-		var err error
-		if d.data.timeout, err = decodeTimeout(f.Value); err != nil {
-			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed time-out: %v", err)
-		}
-	case ":path":
-		d.data.method = f.Value
-	case ":status":
-		code, err := strconv.Atoi(f.Value)
-		if err != nil {
-			d.data.httpErr = status.Errorf(codes.Internal, "transport: malformed http-status: %v", err)
-			return
-		}
-		d.data.httpStatus = &code
-	case "grpc-tags-bin":
-		v, err := decodeBinHeader(f.Value)
-		if err != nil {
-			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-tags-bin: %v", err)
-			return
-		}
-		d.data.statsTags = v
-		d.addMetadata(f.Name, string(v))
-	case "grpc-trace-bin":
-		v, err := decodeBinHeader(f.Value)
-		if err != nil {
-			d.data.grpcErr = status.Errorf(codes.Internal, "transport: malformed grpc-trace-bin: %v", err)
-			return
-		}
-		d.data.statsTrace = v
-		d.addMetadata(f.Name, string(v))
-	default:
-		if isReservedHeader(f.Name) && !isWhitelistedHeader(f.Name) {
-			break
-		}
-		v, err := decodeMetadataHeader(f.Name, f.Value)
-		if err != nil {
-			errorf("Failed to decode metadata header (%q, %q): %v", f.Name, f.Value, err)
-			return
-		}
-		d.addMetadata(f.Name, v)
+	st := &spb.Status{}
+	if err = proto.Unmarshal(v, st); err != nil {
+		return nil, err
 	}
+	return status.FromProto(st), nil
 }
 
 type timeoutUnit uint8
@@ -449,41 +203,6 @@ func timeoutUnitToDuration(u timeoutUnit) (d time.Duration, ok bool) {
 	return
 }
 
-const maxTimeoutValue int64 = 100000000 - 1
-
-// div does integer division and round-up the result. Note that this is
-// equivalent to (d+r-1)/r but has less chance to overflow.
-func div(d, r time.Duration) int64 {
-	if m := d % r; m > 0 {
-		return int64(d/r + 1)
-	}
-	return int64(d / r)
-}
-
-// TODO(zhaoq): It is the simplistic and not bandwidth efficient. Improve it.
-func encodeTimeout(t time.Duration) string {
-	if t <= 0 {
-		return "0n"
-	}
-	if d := div(t, time.Nanosecond); d <= maxTimeoutValue {
-		return strconv.FormatInt(d, 10) + "n"
-	}
-	if d := div(t, time.Microsecond); d <= maxTimeoutValue {
-		return strconv.FormatInt(d, 10) + "u"
-	}
-	if d := div(t, time.Millisecond); d <= maxTimeoutValue {
-		return strconv.FormatInt(d, 10) + "m"
-	}
-	if d := div(t, time.Second); d <= maxTimeoutValue {
-		return strconv.FormatInt(d, 10) + "S"
-	}
-	if d := div(t, time.Minute); d <= maxTimeoutValue {
-		return strconv.FormatInt(d, 10) + "M"
-	}
-	// Note that maxTimeoutValue * time.Hour > MaxInt64.
-	return strconv.FormatInt(div(t, time.Hour), 10) + "H"
-}
-
 func decodeTimeout(s string) (time.Duration, error) {
 	size := len(s)
 	if size < 2 {
@@ -603,8 +322,6 @@ type bufWriter struct {
 	batchSize int
 	conn      net.Conn
 	err       error
-
-	onFlush func()
 }
 
 func newBufWriter(conn net.Conn, batchSize int) *bufWriter {
@@ -641,9 +358,6 @@ func (w *bufWriter) Flush() error {
 	if w.offset == 0 {
 		return nil
 	}
-	if w.onFlush != nil {
-		w.onFlush()
-	}
 	_, w.err = w.conn.Write(w.buf[:w.offset])
 	w.offset = 0
 	return w.err
@@ -675,3 +389,31 @@ func newFramer(conn net.Conn, writeBufferSize, readBufferSize int, maxHeaderList
 	f.fr.ReadMetaHeaders = hpack.NewDecoder(http2InitHeaderTableSize, nil)
 	return f
 }
+
+// parseDialTarget returns the network and address to pass to dialer.
+func parseDialTarget(target string) (string, string) {
+	net := "tcp"
+	m1 := strings.Index(target, ":")
+	m2 := strings.Index(target, ":/")
+	// handle unix:addr which will fail with url.Parse
+	if m1 >= 0 && m2 < 0 {
+		if n := target[0:m1]; n == "unix" {
+			return n, target[m1+1:]
+		}
+	}
+	if m2 >= 0 {
+		t, err := url.Parse(target)
+		if err != nil {
+			return net, target
+		}
+		scheme := t.Scheme
+		addr := t.Path
+		if scheme == "unix" {
+			if addr == "" {
+				addr = t.Host
+			}
+			return scheme, addr
+		}
+	}
+	return net, target
+}

vendor/google.golang.org/grpc/internal/transport/networktype/networktype.go

@@ -0,0 +1,46 @@
+/*
+ *
+ * Copyright 2020 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package networktype declares the network type to be used in the default
+// dialer. Attribute of a resolver.Address.
+package networktype
+
+import (
+	"google.golang.org/grpc/resolver"
+)
+
+// keyType is the key to use for storing State in Attributes.
+type keyType string
+
+const key = keyType("grpc.internal.transport.networktype")
+
+// Set returns a copy of the provided address with attributes containing networkType.
+func Set(address resolver.Address, networkType string) resolver.Address {
+	address.Attributes = address.Attributes.WithValue(key, networkType)
+	return address
+}
+
+// Get returns the network type in the resolver.Address and true, or "", false
+// if not present.
+func Get(address resolver.Address) (string, bool) {
+	v := address.Attributes.Value(key)
+	if v == nil {
+		return "", false
+	}
+	return v.(string), true
+}

vendor/google.golang.org/grpc/internal/transport/proxy.go

@@ -0,0 +1,142 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package transport
+
+import (
+	"bufio"
+	"context"
+	"encoding/base64"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"net/http/httputil"
+	"net/url"
+)
+
+const proxyAuthHeaderKey = "Proxy-Authorization"
+
+var (
+	// The following variable will be overwritten in the tests.
+	httpProxyFromEnvironment = http.ProxyFromEnvironment
+)
+
+func mapAddress(address string) (*url.URL, error) {
+	req := &http.Request{
+		URL: &url.URL{
+			Scheme: "https",
+			Host:   address,
+		},
+	}
+	url, err := httpProxyFromEnvironment(req)
+	if err != nil {
+		return nil, err
+	}
+	return url, nil
+}
+
+// To read a response from a net.Conn, http.ReadResponse() takes a bufio.Reader.
+// It's possible that this reader reads more than what's need for the response and stores
+// those bytes in the buffer.
+// bufConn wraps the original net.Conn and the bufio.Reader to make sure we don't lose the
+// bytes in the buffer.
+type bufConn struct {
+	net.Conn
+	r io.Reader
+}
+
+func (c *bufConn) Read(b []byte) (int, error) {
+	return c.r.Read(b)
+}
+
+func basicAuth(username, password string) string {
+	auth := username + ":" + password
+	return base64.StdEncoding.EncodeToString([]byte(auth))
+}
+
+func doHTTPConnectHandshake(ctx context.Context, conn net.Conn, backendAddr string, proxyURL *url.URL, grpcUA string) (_ net.Conn, err error) {
+	defer func() {
+		if err != nil {
+			conn.Close()
+		}
+	}()
+
+	req := &http.Request{
+		Method: http.MethodConnect,
+		URL:    &url.URL{Host: backendAddr},
+		Header: map[string][]string{"User-Agent": {grpcUA}},
+	}
+	if t := proxyURL.User; t != nil {
+		u := t.Username()
+		p, _ := t.Password()
+		req.Header.Add(proxyAuthHeaderKey, "Basic "+basicAuth(u, p))
+	}
+
+	if err := sendHTTPRequest(ctx, req, conn); err != nil {
+		return nil, fmt.Errorf("failed to write the HTTP request: %v", err)
+	}
+
+	r := bufio.NewReader(conn)
+	resp, err := http.ReadResponse(r, req)
+	if err != nil {
+		return nil, fmt.Errorf("reading server HTTP response: %v", err)
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		dump, err := httputil.DumpResponse(resp, true)
+		if err != nil {
+			return nil, fmt.Errorf("failed to do connect handshake, status code: %s", resp.Status)
+		}
+		return nil, fmt.Errorf("failed to do connect handshake, response: %q", dump)
+	}
+
+	return &bufConn{Conn: conn, r: r}, nil
+}
+
+// proxyDial dials, connecting to a proxy first if necessary. Checks if a proxy
+// is necessary, dials, does the HTTP CONNECT handshake, and returns the
+// connection.
+func proxyDial(ctx context.Context, addr string, grpcUA string) (conn net.Conn, err error) {
+	newAddr := addr
+	proxyURL, err := mapAddress(addr)
+	if err != nil {
+		return nil, err
+	}
+	if proxyURL != nil {
+		newAddr = proxyURL.Host
+	}
+
+	conn, err = (&net.Dialer{}).DialContext(ctx, "tcp", newAddr)
+	if err != nil {
+		return
+	}
+	if proxyURL != nil {
+		// proxy is disabled if proxyURL is nil.
+		conn, err = doHTTPConnectHandshake(ctx, conn, addr, proxyURL, grpcUA)
+	}
+	return
+}
+
+func sendHTTPRequest(ctx context.Context, req *http.Request, conn net.Conn) error {
+	req = req.WithContext(ctx)
+	if err := req.Write(conn); err != nil {
+		return fmt.Errorf("failed to write the HTTP request: %v", err)
+	}
+	return nil
+}

vendor/google.golang.org/grpc/internal/transport/transport.go

@@ -30,16 +30,21 @@ import (
 	"net"
 	"sync"
 	"sync/atomic"
+	"time"
 
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
+	"google.golang.org/grpc/internal/channelz"
 	"google.golang.org/grpc/keepalive"
 	"google.golang.org/grpc/metadata"
+	"google.golang.org/grpc/resolver"
 	"google.golang.org/grpc/stats"
 	"google.golang.org/grpc/status"
 	"google.golang.org/grpc/tap"
 )
 
+const logLevel = 2
+
 type bufferPool struct {
 	pool sync.Pool
 }
@@ -238,6 +243,7 @@ type Stream struct {
 	ctx          context.Context    // the associated context of the stream
 	cancel       context.CancelFunc // always nil for client side Stream
 	done         chan struct{}      // closed at the end of stream to unblock writers. On the client side.
+	doneFunc     func()             // invoked at the end of stream on client side.
 	ctxDone      <-chan struct{}    // same as done chan but for server side. Cache of ctx.Done() (for performance)
 	method       string             // the associated RPC method of the stream
 	recvCompress string
@@ -514,26 +520,21 @@ const (
 // ServerConfig consists of all the configurations to establish a server transport.
 type ServerConfig struct {
 	MaxStreams            uint32
-	AuthInfo              credentials.AuthInfo
+	ConnectionTimeout     time.Duration
+	Credentials           credentials.TransportCredentials
 	InTapHandle           tap.ServerInHandle
-	StatsHandler          stats.Handler
+	StatsHandlers         []stats.Handler
 	KeepaliveParams       keepalive.ServerParameters
 	KeepalivePolicy       keepalive.EnforcementPolicy
 	InitialWindowSize     int32
 	InitialConnWindowSize int32
 	WriteBufferSize       int
 	ReadBufferSize        int
-	ChannelzParentID      int64
+	ChannelzParentID      *channelz.Identifier
 	MaxHeaderListSize     *uint32
 	HeaderTableSize       *uint32
 }
 
-// NewServerTransport creates a ServerTransport with conn or non-nil error
-// if it fails.
-func NewServerTransport(protocol string, conn net.Conn, config *ServerConfig) (ServerTransport, error) {
-	return newHTTP2Server(conn, config)
-}
-
 // ConnectOptions covers all relevant options for communicating with the server.
 type ConnectOptions struct {
 	// UserAgent is the application user agent.
@@ -552,8 +553,8 @@ type ConnectOptions struct {
 	CredsBundle credentials.Bundle
 	// KeepaliveParams stores the keepalive parameters.
 	KeepaliveParams keepalive.ClientParameters
-	// StatsHandler stores the handler for stats.
-	StatsHandler stats.Handler
+	// StatsHandlers stores the handler for stats.
+	StatsHandlers []stats.Handler
 	// InitialWindowSize sets the initial window size for a stream.
 	InitialWindowSize int32
 	// InitialConnWindowSize sets the initial window size for a connection.
@@ -563,22 +564,17 @@ type ConnectOptions struct {
 	// ReadBufferSize sets the size of read buffer, which in turn determines how much data can be read at most for one read syscall.
 	ReadBufferSize int
 	// ChannelzParentID sets the addrConn id which initiate the creation of this client transport.
-	ChannelzParentID int64
+	ChannelzParentID *channelz.Identifier
 	// MaxHeaderListSize sets the max (uncompressed) size of header list that is prepared to be received.
 	MaxHeaderListSize *uint32
-}
-
-// TargetInfo contains the information of the target such as network address and metadata.
-type TargetInfo struct {
-	Addr      string
-	Metadata  interface{}
-	Authority string
+	// UseProxy specifies if a proxy should be used.
+	UseProxy bool
 }
 
 // NewClientTransport establishes the transport with the required ConnectOptions
 // and returns it to the caller.
-func NewClientTransport(connectCtx, ctx context.Context, target TargetInfo, opts ConnectOptions, onPrefaceReceipt func(), onGoAway func(GoAwayReason), onClose func()) (ClientTransport, error) {
-	return newHTTP2Client(connectCtx, ctx, target, opts, onPrefaceReceipt, onGoAway, onClose)
+func NewClientTransport(connectCtx, ctx context.Context, addr resolver.Address, opts ConnectOptions, onPrefaceReceipt func(), onGoAway func(GoAwayReason), onClose func()) (ClientTransport, error) {
+	return newHTTP2Client(connectCtx, ctx, addr, opts, onPrefaceReceipt, onGoAway, onClose)
 }
 
 // Options provides additional hints and information for message
@@ -613,6 +609,8 @@ type CallHdr struct {
 	ContentSubtype string
 
 	PreviousAttempts int // value of grpc-previous-rpc-attempts header to set
+
+	DoneFunc func() // called when the stream is finished
 }
 
 // ClientTransport is the common interface for all gRPC client-side transport
@@ -621,7 +619,7 @@ type ClientTransport interface {
 	// Close tears down this transport. Once it returns, the transport
 	// should not be accessed any more. The caller must make sure this
 	// is called only once.
-	Close() error
+	Close(err error)
 
 	// GracefulClose starts to tear down the transport: the transport will stop
 	// accepting new RPCs and NewStream will return error. Once all streams are
@@ -655,8 +653,9 @@ type ClientTransport interface {
 	// HTTP/2).
 	GoAway() <-chan struct{}
 
-	// GetGoAwayReason returns the reason why GoAway frame was received.
-	GetGoAwayReason() GoAwayReason
+	// GetGoAwayReason returns the reason why GoAway frame was received, along
+	// with a human readable string with debug info.
+	GetGoAwayReason() (GoAwayReason, string)
 
 	// RemoteAddr returns the remote network address.
 	RemoteAddr() net.Addr
@@ -692,7 +691,7 @@ type ServerTransport interface {
 	// Close tears down the transport. Once it is called, the transport
 	// should not be accessed any more. All the pending streams and their
 	// handlers will be terminated asynchronously.
-	Close() error
+	Close()
 
 	// RemoteAddr returns the remote network address.
 	RemoteAddr() net.Addr
@@ -743,6 +742,12 @@ func (e ConnectionError) Origin() error {
 	return e.err
 }
 
+// Unwrap returns the original error of this connection error or nil when the
+// origin is nil.
+func (e ConnectionError) Unwrap() error {
+	return e.err
+}
+
 var (
 	// ErrConnClosing indicates that the transport is closing.
 	ErrConnClosing = connectionErrorf(true, nil, "transport is closing")

vendor/google.golang.org/grpc/internal/xds_handshake_cluster.go

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2021 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package internal
+
+import (
+	"google.golang.org/grpc/attributes"
+	"google.golang.org/grpc/resolver"
+)
+
+// handshakeClusterNameKey is the type used as the key to store cluster name in
+// the Attributes field of resolver.Address.
+type handshakeClusterNameKey struct{}
+
+// SetXDSHandshakeClusterName returns a copy of addr in which the Attributes field
+// is updated with the cluster name.
+func SetXDSHandshakeClusterName(addr resolver.Address, clusterName string) resolver.Address {
+	addr.Attributes = addr.Attributes.WithValue(handshakeClusterNameKey{}, clusterName)
+	return addr
+}
+
+// GetXDSHandshakeClusterName returns cluster name stored in attr.
+func GetXDSHandshakeClusterName(attr *attributes.Attributes) (string, bool) {
+	v := attr.Value(handshakeClusterNameKey{})
+	name, ok := v.(string)
+	return name, ok
+}