TUN-8407: Upgrade go to version 1.22.2

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

@@ -67,7 +67,7 @@ var (
 	errConnDrain = errors.New("grpc: the connection is drained")
 	// errConnClosing indicates that the connection is closing.
 	errConnClosing = errors.New("grpc: the connection is closing")
-	// errConnIdling indicates the the connection is being closed as the channel
+	// errConnIdling indicates the connection is being closed as the channel
 	// is moving to an idle mode due to inactivity.
 	errConnIdling = errors.New("grpc: the connection is closing due to channel idleness")
 	// invalidDefaultServiceConfigErrPrefix is used to prefix the json parsing error for the default
@@ -101,11 +101,6 @@ const (
 	defaultReadBufSize  = 32 * 1024
 )
 
-// Dial creates a client connection to the given target.
-func Dial(target string, opts ...DialOption) (*ClientConn, error) {
-	return DialContext(context.Background(), target, opts...)
-}
-
 type defaultConfigSelector struct {
 	sc *ServiceConfig
 }
@@ -117,13 +112,22 @@ func (dcs *defaultConfigSelector) SelectConfig(rpcInfo iresolver.RPCInfo) (*ires
 	}, nil
 }
 
-// newClient returns a new client in idle mode.
-func newClient(target string, opts ...DialOption) (conn *ClientConn, err error) {
+// NewClient creates a new gRPC "channel" for the target URI provided.  No I/O
+// is performed.  Use of the ClientConn for RPCs will automatically cause it to
+// connect.  Connect may be used to manually create a connection, but for most
+// users this is unnecessary.
+//
+// The target name syntax is defined in
+// https://github.com/grpc/grpc/blob/master/doc/naming.md.  e.g. to use dns
+// resolver, a "dns:///" prefix should be applied to the target.
+//
+// The DialOptions returned by WithBlock, WithTimeout, and
+// WithReturnConnectionError are ignored by this function.
+func NewClient(target string, opts ...DialOption) (conn *ClientConn, err error) {
 	cc := &ClientConn{
 		target: target,
 		conns:  make(map[*addrConn]struct{}),
 		dopts:  defaultDialOptions(),
-		czData: new(channelzData),
 	}
 
 	cc.retryThrottler.Store((*retryThrottler)(nil))
@@ -175,15 +179,15 @@ func newClient(target string, opts ...DialOption) (conn *ClientConn, err error)
 
 	// Determine the resolver to use.
 	if err := cc.parseTargetAndFindResolver(); err != nil {
-		channelz.RemoveEntry(cc.channelzID)
+		channelz.RemoveEntry(cc.channelz.ID)
 		return nil, err
 	}
 	if err = cc.determineAuthority(); err != nil {
-		channelz.RemoveEntry(cc.channelzID)
+		channelz.RemoveEntry(cc.channelz.ID)
 		return nil, err
 	}
 
-	cc.csMgr = newConnectivityStateManager(cc.ctx, cc.channelzID)
+	cc.csMgr = newConnectivityStateManager(cc.ctx, cc.channelz)
 	cc.pickerWrapper = newPickerWrapper(cc.dopts.copts.StatsHandlers)
 
 	cc.initIdleStateLocked() // Safe to call without the lock, since nothing else has a reference to cc.
@@ -191,39 +195,36 @@ func newClient(target string, opts ...DialOption) (conn *ClientConn, err error)
 	return cc, nil
 }
 
-// DialContext creates a client connection to the given target. By default, it's
-// a non-blocking dial (the function won't wait for connections to be
-// established, and connecting happens in the background). To make it a blocking
-// dial, use WithBlock() dial option.
+// Dial calls DialContext(context.Background(), target, opts...).
 //
-// In the non-blocking case, the ctx does not act against the connection. It
-// only controls the setup steps.
+// Deprecated: use NewClient instead.  Will be supported throughout 1.x.
+func Dial(target string, opts ...DialOption) (*ClientConn, error) {
+	return DialContext(context.Background(), target, opts...)
+}
+
+// DialContext calls NewClient and then exits idle mode.  If WithBlock(true) is
+// used, it calls Connect and WaitForStateChange until either the context
+// expires or the state of the ClientConn is Ready.
 //
-// In the blocking case, ctx can be used to cancel or expire the pending
-// connection. Once this function returns, the cancellation and expiration of
-// ctx will be noop. Users should call ClientConn.Close to terminate all the
-// pending operations after this function returns.
+// One subtle difference between NewClient and Dial and DialContext is that the
+// former uses "dns" as the default name resolver, while the latter use
+// "passthrough" for backward compatibility.  This distinction should not matter
+// to most users, but could matter to legacy users that specify a custom dialer
+// and expect it to receive the target string directly.
 //
-// The target name syntax is defined in
-// https://github.com/grpc/grpc/blob/master/doc/naming.md.
-// e.g. to use dns resolver, a "dns:///" prefix should be applied to the target.
+// Deprecated: use NewClient instead.  Will be supported throughout 1.x.
 func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *ClientConn, err error) {
-	cc, err := newClient(target, opts...)
+	// At the end of this method, we kick the channel out of idle, rather than
+	// waiting for the first rpc.
+	opts = append([]DialOption{withDefaultScheme("passthrough")}, opts...)
+	cc, err := NewClient(target, opts...)
 	if err != nil {
 		return nil, err
 	}
 
 	// We start the channel off in idle mode, but kick it out of idle now,
-	// instead of waiting for the first RPC. Other gRPC implementations do wait
-	// for the first RPC to kick the channel out of idle. But doing so would be
-	// a major behavior change for our users who are used to seeing the channel
-	// active after Dial.
-	//
-	// Taking this approach of kicking it out of idle at the end of this method
-	// allows us to share the code between channel creation and exiting idle
-	// mode. This will also make it easy for us to switch to starting the
-	// channel off in idle, i.e. by making newClient exported.
-
+	// instead of waiting for the first RPC.  This is the legacy behavior of
+	// Dial.
 	defer func() {
 		if err != nil {
 			cc.Close()
@@ -291,17 +292,17 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *
 // addTraceEvent is a helper method to add a trace event on the channel. If the
 // channel is a nested one, the same event is also added on the parent channel.
 func (cc *ClientConn) addTraceEvent(msg string) {
-	ted := &channelz.TraceEventDesc{
+	ted := &channelz.TraceEvent{
 		Desc:     fmt.Sprintf("Channel %s", msg),
 		Severity: channelz.CtInfo,
 	}
-	if cc.dopts.channelzParentID != nil {
-		ted.Parent = &channelz.TraceEventDesc{
-			Desc:     fmt.Sprintf("Nested channel(id:%d) %s", cc.channelzID.Int(), msg),
+	if cc.dopts.channelzParent != nil {
+		ted.Parent = &channelz.TraceEvent{
+			Desc:     fmt.Sprintf("Nested channel(id:%d) %s", cc.channelz.ID, msg),
 			Severity: channelz.CtInfo,
 		}
 	}
-	channelz.AddTraceEvent(logger, cc.channelzID, 0, ted)
+	channelz.AddTraceEvent(logger, cc.channelz, 0, ted)
 }
 
 type idler ClientConn
@@ -418,14 +419,15 @@ func (cc *ClientConn) validateTransportCredentials() error {
 }
 
 // channelzRegistration registers the newly created ClientConn with channelz and
-// stores the returned identifier in `cc.channelzID` and `cc.csMgr.channelzID`.
-// A channelz trace event is emitted for ClientConn creation. If the newly
-// created ClientConn is a nested one, i.e a valid parent ClientConn ID is
-// specified via a dial option, the trace event is also added to the parent.
+// stores the returned identifier in `cc.channelz`.  A channelz trace event is
+// emitted for ClientConn creation. If the newly created ClientConn is a nested
+// one, i.e a valid parent ClientConn ID is specified via a dial option, the
+// trace event is also added to the parent.
 //
 // Doesn't grab cc.mu as this method is expected to be called only at Dial time.
 func (cc *ClientConn) channelzRegistration(target string) {
-	cc.channelzID = channelz.RegisterChannel(&channelzChannel{cc}, cc.dopts.channelzParentID, target)
+	parentChannel, _ := cc.dopts.channelzParent.(*channelz.Channel)
+	cc.channelz = channelz.RegisterChannel(parentChannel, target)
 	cc.addTraceEvent("created")
 }
 
@@ -492,11 +494,11 @@ func getChainStreamer(interceptors []StreamClientInterceptor, curr int, finalStr
 }
 
 // newConnectivityStateManager creates an connectivityStateManager with
-// the specified id.
-func newConnectivityStateManager(ctx context.Context, id *channelz.Identifier) *connectivityStateManager {
+// the specified channel.
+func newConnectivityStateManager(ctx context.Context, channel *channelz.Channel) *connectivityStateManager {
 	return &connectivityStateManager{
-		channelzID: id,
-		pubSub:     grpcsync.NewPubSub(ctx),
+		channelz: channel,
+		pubSub:   grpcsync.NewPubSub(ctx),
 	}
 }
 
@@ -510,7 +512,7 @@ type connectivityStateManager struct {
 	mu         sync.Mutex
 	state      connectivity.State
 	notifyChan chan struct{}
-	channelzID *channelz.Identifier
+	channelz   *channelz.Channel
 	pubSub     *grpcsync.PubSub
 }
 
@@ -527,9 +529,10 @@ func (csm *connectivityStateManager) updateState(state connectivity.State) {
 		return
 	}
 	csm.state = state
+	csm.channelz.ChannelMetrics.State.Store(&state)
 	csm.pubSub.Publish(state)
 
-	channelz.Infof(logger, csm.channelzID, "Channel Connectivity change to %v", state)
+	channelz.Infof(logger, csm.channelz, "Channel Connectivity change to %v", state)
 	if csm.notifyChan != nil {
 		// There are other goroutines waiting on this channel.
 		close(csm.notifyChan)
@@ -583,12 +586,12 @@ type ClientConn struct {
 	cancel context.CancelFunc // Cancelled on close.
 
 	// The following are initialized at dial time, and are read-only after that.
-	target          string               // User's dial target.
-	parsedTarget    resolver.Target      // See parseTargetAndFindResolver().
-	authority       string               // See determineAuthority().
-	dopts           dialOptions          // Default and user specified dial options.
-	channelzID      *channelz.Identifier // Channelz identifier for the channel.
-	resolverBuilder resolver.Builder     // See parseTargetAndFindResolver().
+	target          string            // User's dial target.
+	parsedTarget    resolver.Target   // See parseTargetAndFindResolver().
+	authority       string            // See determineAuthority().
+	dopts           dialOptions       // Default and user specified dial options.
+	channelz        *channelz.Channel // Channelz object.
+	resolverBuilder resolver.Builder  // See parseTargetAndFindResolver().
 	idlenessMgr     *idle.Manager
 
 	// The following provide their own synchronization, and therefore don't
@@ -596,7 +599,6 @@ type ClientConn struct {
 	csMgr              *connectivityStateManager
 	pickerWrapper      *pickerWrapper
 	safeConfigSelector iresolver.SafeConfigSelector
-	czData             *channelzData
 	retryThrottler     atomic.Value // Updated from service config.
 
 	// mu protects the following fields.
@@ -690,6 +692,7 @@ func (cc *ClientConn) waitForResolvedAddrs(ctx context.Context) error {
 var emptyServiceConfig *ServiceConfig
 
 func init() {
+	balancer.Register(pickfirstBuilder{})
 	cfg := parseServiceConfig("{}")
 	if cfg.Err != nil {
 		panic(fmt.Sprintf("impossible error parsing empty service config: %v", cfg.Err))
@@ -707,15 +710,15 @@ func init() {
 	}
 }
 
-func (cc *ClientConn) maybeApplyDefaultServiceConfig(addrs []resolver.Address) {
+func (cc *ClientConn) maybeApplyDefaultServiceConfig() {
 	if cc.sc != nil {
-		cc.applyServiceConfigAndBalancer(cc.sc, nil, addrs)
+		cc.applyServiceConfigAndBalancer(cc.sc, nil)
 		return
 	}
 	if cc.dopts.defaultServiceConfig != nil {
-		cc.applyServiceConfigAndBalancer(cc.dopts.defaultServiceConfig, &defaultConfigSelector{cc.dopts.defaultServiceConfig}, addrs)
+		cc.applyServiceConfigAndBalancer(cc.dopts.defaultServiceConfig, &defaultConfigSelector{cc.dopts.defaultServiceConfig})
 	} else {
-		cc.applyServiceConfigAndBalancer(emptyServiceConfig, &defaultConfigSelector{emptyServiceConfig}, addrs)
+		cc.applyServiceConfigAndBalancer(emptyServiceConfig, &defaultConfigSelector{emptyServiceConfig})
 	}
 }
 
@@ -733,7 +736,7 @@ func (cc *ClientConn) updateResolverStateAndUnlock(s resolver.State, err error)
 		// May need to apply the initial service config in case the resolver
 		// doesn't support service configs, or doesn't provide a service config
 		// with the new addresses.
-		cc.maybeApplyDefaultServiceConfig(nil)
+		cc.maybeApplyDefaultServiceConfig()
 
 		cc.balancerWrapper.resolverError(err)
 
@@ -744,10 +747,10 @@ func (cc *ClientConn) updateResolverStateAndUnlock(s resolver.State, err error)
 
 	var ret error
 	if cc.dopts.disableServiceConfig {
-		channelz.Infof(logger, cc.channelzID, "ignoring service config from resolver (%v) and applying the default because service config is disabled", s.ServiceConfig)
-		cc.maybeApplyDefaultServiceConfig(s.Addresses)
+		channelz.Infof(logger, cc.channelz, "ignoring service config from resolver (%v) and applying the default because service config is disabled", s.ServiceConfig)
+		cc.maybeApplyDefaultServiceConfig()
 	} else if s.ServiceConfig == nil {
-		cc.maybeApplyDefaultServiceConfig(s.Addresses)
+		cc.maybeApplyDefaultServiceConfig()
 		// TODO: do we need to apply a failing LB policy if there is no
 		// default, per the error handling design?
 	} else {
@@ -755,12 +758,12 @@ func (cc *ClientConn) updateResolverStateAndUnlock(s resolver.State, err error)
 			configSelector := iresolver.GetConfigSelector(s)
 			if configSelector != nil {
 				if len(s.ServiceConfig.Config.(*ServiceConfig).Methods) != 0 {
-					channelz.Infof(logger, cc.channelzID, "method configs in service config will be ignored due to presence of config selector")
+					channelz.Infof(logger, cc.channelz, "method configs in service config will be ignored due to presence of config selector")
 				}
 			} else {
 				configSelector = &defaultConfigSelector{sc}
 			}
-			cc.applyServiceConfigAndBalancer(sc, configSelector, s.Addresses)
+			cc.applyServiceConfigAndBalancer(sc, configSelector)
 		} else {
 			ret = balancer.ErrBadResolverState
 			if cc.sc == nil {
@@ -775,7 +778,7 @@ func (cc *ClientConn) updateResolverStateAndUnlock(s resolver.State, err error)
 
 	var balCfg serviceconfig.LoadBalancingConfig
 	if cc.sc != nil && cc.sc.lbConfig != nil {
-		balCfg = cc.sc.lbConfig.cfg
+		balCfg = cc.sc.lbConfig
 	}
 	bw := cc.balancerWrapper
 	cc.mu.Unlock()
@@ -834,22 +837,17 @@ func (cc *ClientConn) newAddrConnLocked(addrs []resolver.Address, opts balancer.
 		addrs:        copyAddressesWithoutBalancerAttributes(addrs),
 		scopts:       opts,
 		dopts:        cc.dopts,
-		czData:       new(channelzData),
+		channelz:     channelz.RegisterSubChannel(cc.channelz.ID, ""),
 		resetBackoff: make(chan struct{}),
 		stateChan:    make(chan struct{}),
 	}
 	ac.ctx, ac.cancel = context.WithCancel(cc.ctx)
 
-	var err error
-	ac.channelzID, err = channelz.RegisterSubChannel(ac, cc.channelzID, "")
-	if err != nil {
-		return nil, err
-	}
-	channelz.AddTraceEvent(logger, ac.channelzID, 0, &channelz.TraceEventDesc{
+	channelz.AddTraceEvent(logger, ac.channelz, 0, &channelz.TraceEvent{
 		Desc:     "Subchannel created",
 		Severity: channelz.CtInfo,
-		Parent: &channelz.TraceEventDesc{
-			Desc:     fmt.Sprintf("Subchannel(id:%d) created", ac.channelzID.Int()),
+		Parent: &channelz.TraceEvent{
+			Desc:     fmt.Sprintf("Subchannel(id:%d) created", ac.channelz.ID),
 			Severity: channelz.CtInfo,
 		},
 	})
@@ -872,38 +870,27 @@ func (cc *ClientConn) removeAddrConn(ac *addrConn, err error) {
 	ac.tearDown(err)
 }
 
-func (cc *ClientConn) channelzMetric() *channelz.ChannelInternalMetric {
-	return &channelz.ChannelInternalMetric{
-		State:                    cc.GetState(),
-		Target:                   cc.target,
-		CallsStarted:             atomic.LoadInt64(&cc.czData.callsStarted),
-		CallsSucceeded:           atomic.LoadInt64(&cc.czData.callsSucceeded),
-		CallsFailed:              atomic.LoadInt64(&cc.czData.callsFailed),
-		LastCallStartedTimestamp: time.Unix(0, atomic.LoadInt64(&cc.czData.lastCallStartedTime)),
-	}
-}
-
 // Target returns the target string of the ClientConn.
-//
-// # Experimental
-//
-// Notice: This API is EXPERIMENTAL and may be changed or removed in a
-// later release.
 func (cc *ClientConn) Target() string {
 	return cc.target
 }
 
+// CanonicalTarget returns the canonical target string of the ClientConn.
+func (cc *ClientConn) CanonicalTarget() string {
+	return cc.parsedTarget.String()
+}
+
 func (cc *ClientConn) incrCallsStarted() {
-	atomic.AddInt64(&cc.czData.callsStarted, 1)
-	atomic.StoreInt64(&cc.czData.lastCallStartedTime, time.Now().UnixNano())
+	cc.channelz.ChannelMetrics.CallsStarted.Add(1)
+	cc.channelz.ChannelMetrics.LastCallStartedTimestamp.Store(time.Now().UnixNano())
 }
 
 func (cc *ClientConn) incrCallsSucceeded() {
-	atomic.AddInt64(&cc.czData.callsSucceeded, 1)
+	cc.channelz.ChannelMetrics.CallsSucceeded.Add(1)
 }
 
 func (cc *ClientConn) incrCallsFailed() {
-	atomic.AddInt64(&cc.czData.callsFailed, 1)
+	cc.channelz.ChannelMetrics.CallsFailed.Add(1)
 }
 
 // connect starts creating a transport.
@@ -947,7 +934,7 @@ func equalAddresses(a, b []resolver.Address) bool {
 // connections or connection attempts.
 func (ac *addrConn) updateAddrs(addrs []resolver.Address) {
 	ac.mu.Lock()
-	channelz.Infof(logger, ac.channelzID, "addrConn: updateAddrs curAddr: %v, addrs: %v", pretty.ToJSON(ac.curAddr), pretty.ToJSON(addrs))
+	channelz.Infof(logger, ac.channelz, "addrConn: updateAddrs curAddr: %v, addrs: %v", pretty.ToJSON(ac.curAddr), pretty.ToJSON(addrs))
 
 	addrs = copyAddressesWithoutBalancerAttributes(addrs)
 	if equalAddresses(ac.addrs, addrs) {
@@ -1067,7 +1054,7 @@ func (cc *ClientConn) getTransport(ctx context.Context, failfast bool, method st
 	})
 }
 
-func (cc *ClientConn) applyServiceConfigAndBalancer(sc *ServiceConfig, configSelector iresolver.ConfigSelector, addrs []resolver.Address) {
+func (cc *ClientConn) applyServiceConfigAndBalancer(sc *ServiceConfig, configSelector iresolver.ConfigSelector) {
 	if sc == nil {
 		// should never reach here.
 		return
@@ -1088,17 +1075,6 @@ func (cc *ClientConn) applyServiceConfigAndBalancer(sc *ServiceConfig, configSel
 	} else {
 		cc.retryThrottler.Store((*retryThrottler)(nil))
 	}
-
-	var newBalancerName string
-	if cc.sc == nil || (cc.sc.lbConfig == nil && cc.sc.LB == nil) {
-		// No service config or no LB policy specified in config.
-		newBalancerName = PickFirstBalancerName
-	} else if cc.sc.lbConfig != nil {
-		newBalancerName = cc.sc.lbConfig.name
-	} else { // cc.sc.LB != nil
-		newBalancerName = *cc.sc.LB
-	}
-	cc.balancerWrapper.switchTo(newBalancerName)
 }
 
 func (cc *ClientConn) resolveNow(o resolver.ResolveNowOptions) {
@@ -1174,7 +1150,7 @@ func (cc *ClientConn) Close() error {
 	// TraceEvent needs to be called before RemoveEntry, as TraceEvent may add
 	// trace reference to the entity being deleted, and thus prevent it from being
 	// deleted right away.
-	channelz.RemoveEntry(cc.channelzID)
+	channelz.RemoveEntry(cc.channelz.ID)
 
 	return nil
 }
@@ -1206,8 +1182,7 @@ type addrConn struct {
 	backoffIdx   int // Needs to be stateful for resetConnectBackoff.
 	resetBackoff chan struct{}
 
-	channelzID *channelz.Identifier
-	czData     *channelzData
+	channelz *channelz.SubChannel
 }
 
 // Note: this requires a lock on ac.mu.
@@ -1219,10 +1194,11 @@ func (ac *addrConn) updateConnectivityState(s connectivity.State, lastErr error)
 	close(ac.stateChan)
 	ac.stateChan = make(chan struct{})
 	ac.state = s
+	ac.channelz.ChannelMetrics.State.Store(&s)
 	if lastErr == nil {
-		channelz.Infof(logger, ac.channelzID, "Subchannel Connectivity change to %v", s)
+		channelz.Infof(logger, ac.channelz, "Subchannel Connectivity change to %v", s)
 	} else {
-		channelz.Infof(logger, ac.channelzID, "Subchannel Connectivity change to %v, last error: %s", s, lastErr)
+		channelz.Infof(logger, ac.channelz, "Subchannel Connectivity change to %v, last error: %s", s, lastErr)
 	}
 	ac.acbw.updateState(s, lastErr)
 }
@@ -1335,7 +1311,7 @@ func (ac *addrConn) tryAllAddrs(ctx context.Context, addrs []resolver.Address, c
 		}
 		ac.mu.Unlock()
 
-		channelz.Infof(logger, ac.channelzID, "Subchannel picks a new address %q to connect", addr.Addr)
+		channelz.Infof(logger, ac.channelz, "Subchannel picks a new address %q to connect", addr.Addr)
 
 		err := ac.createTransport(ctx, addr, copts, connectDeadline)
 		if err == nil {
@@ -1388,7 +1364,7 @@ func (ac *addrConn) createTransport(ctx context.Context, addr resolver.Address,
 
 	connectCtx, cancel := context.WithDeadline(ctx, connectDeadline)
 	defer cancel()
-	copts.ChannelzParentID = ac.channelzID
+	copts.ChannelzParent = ac.channelz
 
 	newTr, err := transport.NewClientTransport(connectCtx, ac.cc.ctx, addr, copts, onClose)
 	if err != nil {
@@ -1397,7 +1373,7 @@ func (ac *addrConn) createTransport(ctx context.Context, addr resolver.Address,
 		}
 		// newTr is either nil, or closed.
 		hcancel()
-		channelz.Warningf(logger, ac.channelzID, "grpc: addrConn.createTransport failed to connect to %s. Err: %v", addr, err)
+		channelz.Warningf(logger, ac.channelz, "grpc: addrConn.createTransport failed to connect to %s. Err: %v", addr, err)
 		return err
 	}
 
@@ -1469,7 +1445,7 @@ func (ac *addrConn) startHealthCheck(ctx context.Context) {
 		// The health package is not imported to set health check function.
 		//
 		// TODO: add a link to the health check doc in the error message.
-		channelz.Error(logger, ac.channelzID, "Health check is requested but health check function is not set.")
+		channelz.Error(logger, ac.channelz, "Health check is requested but health check function is not set.")
 		return
 	}
 
@@ -1499,9 +1475,9 @@ func (ac *addrConn) startHealthCheck(ctx context.Context) {
 		err := ac.cc.dopts.healthCheckFunc(ctx, newStream, setConnectivityState, healthCheckConfig.ServiceName)
 		if err != nil {
 			if status.Code(err) == codes.Unimplemented {
-				channelz.Error(logger, ac.channelzID, "Subchannel health check is unimplemented at server side, thus health check is disabled")
+				channelz.Error(logger, ac.channelz, "Subchannel health check is unimplemented at server side, thus health check is disabled")
 			} else {
-				channelz.Errorf(logger, ac.channelzID, "Health checking failed: %v", err)
+				channelz.Errorf(logger, ac.channelz, "Health checking failed: %v", err)
 			}
 		}
 	}()
@@ -1566,18 +1542,18 @@ func (ac *addrConn) tearDown(err error) {
 	ac.cancel()
 	ac.curAddr = resolver.Address{}
 
-	channelz.AddTraceEvent(logger, ac.channelzID, 0, &channelz.TraceEventDesc{
+	channelz.AddTraceEvent(logger, ac.channelz, 0, &channelz.TraceEvent{
 		Desc:     "Subchannel deleted",
 		Severity: channelz.CtInfo,
-		Parent: &channelz.TraceEventDesc{
-			Desc:     fmt.Sprintf("Subchannel(id:%d) deleted", ac.channelzID.Int()),
+		Parent: &channelz.TraceEvent{
+			Desc:     fmt.Sprintf("Subchannel(id:%d) deleted", ac.channelz.ID),
 			Severity: channelz.CtInfo,
 		},
 	})
 	// TraceEvent needs to be called before RemoveEntry, as TraceEvent may add
 	// trace reference to the entity being deleted, and thus prevent it from
 	// being deleted right away.
-	channelz.RemoveEntry(ac.channelzID)
+	channelz.RemoveEntry(ac.channelz.ID)
 	ac.mu.Unlock()
 
 	// We have to release the lock before the call to GracefulClose/Close here
@@ -1604,39 +1580,6 @@ func (ac *addrConn) tearDown(err error) {
 	}
 }
 
-func (ac *addrConn) getState() connectivity.State {
-	ac.mu.Lock()
-	defer ac.mu.Unlock()
-	return ac.state
-}
-
-func (ac *addrConn) ChannelzMetric() *channelz.ChannelInternalMetric {
-	ac.mu.Lock()
-	addr := ac.curAddr.Addr
-	ac.mu.Unlock()
-	return &channelz.ChannelInternalMetric{
-		State:                    ac.getState(),
-		Target:                   addr,
-		CallsStarted:             atomic.LoadInt64(&ac.czData.callsStarted),
-		CallsSucceeded:           atomic.LoadInt64(&ac.czData.callsSucceeded),
-		CallsFailed:              atomic.LoadInt64(&ac.czData.callsFailed),
-		LastCallStartedTimestamp: time.Unix(0, atomic.LoadInt64(&ac.czData.lastCallStartedTime)),
-	}
-}
-
-func (ac *addrConn) incrCallsStarted() {
-	atomic.AddInt64(&ac.czData.callsStarted, 1)
-	atomic.StoreInt64(&ac.czData.lastCallStartedTime, time.Now().UnixNano())
-}
-
-func (ac *addrConn) incrCallsSucceeded() {
-	atomic.AddInt64(&ac.czData.callsSucceeded, 1)
-}
-
-func (ac *addrConn) incrCallsFailed() {
-	atomic.AddInt64(&ac.czData.callsFailed, 1)
-}
-
 type retryThrottler struct {
 	max    float64
 	thresh float64
@@ -1674,12 +1617,17 @@ func (rt *retryThrottler) successfulRPC() {
 	}
 }
 
-type channelzChannel struct {
-	cc *ClientConn
+func (ac *addrConn) incrCallsStarted() {
+	ac.channelz.ChannelMetrics.CallsStarted.Add(1)
+	ac.channelz.ChannelMetrics.LastCallStartedTimestamp.Store(time.Now().UnixNano())
 }
 
-func (c *channelzChannel) ChannelzMetric() *channelz.ChannelInternalMetric {
-	return c.cc.channelzMetric()
+func (ac *addrConn) incrCallsSucceeded() {
+	ac.channelz.ChannelMetrics.CallsSucceeded.Add(1)
+}
+
+func (ac *addrConn) incrCallsFailed() {
+	ac.channelz.ChannelMetrics.CallsFailed.Add(1)
 }
 
 // ErrClientConnTimeout indicates that the ClientConn cannot establish the
@@ -1721,14 +1669,14 @@ func (cc *ClientConn) connectionError() error {
 //
 // Doesn't grab cc.mu as this method is expected to be called only at Dial time.
 func (cc *ClientConn) parseTargetAndFindResolver() error {
-	channelz.Infof(logger, cc.channelzID, "original dial target is: %q", cc.target)
+	channelz.Infof(logger, cc.channelz, "original dial target is: %q", cc.target)
 
 	var rb resolver.Builder
 	parsedTarget, err := parseTarget(cc.target)
 	if err != nil {
-		channelz.Infof(logger, cc.channelzID, "dial target %q parse failed: %v", cc.target, err)
+		channelz.Infof(logger, cc.channelz, "dial target %q parse failed: %v", cc.target, err)
 	} else {
-		channelz.Infof(logger, cc.channelzID, "parsed dial target is: %#v", parsedTarget)
+		channelz.Infof(logger, cc.channelz, "parsed dial target is: %#v", parsedTarget)
 		rb = cc.getResolver(parsedTarget.URL.Scheme)
 		if rb != nil {
 			cc.parsedTarget = parsedTarget
@@ -1740,17 +1688,22 @@ func (cc *ClientConn) parseTargetAndFindResolver() error {
 	// We are here because the user's dial target did not contain a scheme or
 	// specified an unregistered scheme. We should fallback to the default
 	// scheme, except when a custom dialer is specified in which case, we should
-	// always use passthrough scheme.
-	defScheme := resolver.GetDefaultScheme()
-	channelz.Infof(logger, cc.channelzID, "fallback to scheme %q", defScheme)
+	// always use passthrough scheme. For either case, we need to respect any overridden
+	// global defaults set by the user.
+	defScheme := cc.dopts.defaultScheme
+	if internal.UserSetDefaultScheme {
+		defScheme = resolver.GetDefaultScheme()
+	}
+
+	channelz.Infof(logger, cc.channelz, "fallback to scheme %q", defScheme)
 	canonicalTarget := defScheme + ":///" + cc.target
 
 	parsedTarget, err = parseTarget(canonicalTarget)
 	if err != nil {
-		channelz.Infof(logger, cc.channelzID, "dial target %q parse failed: %v", canonicalTarget, err)
+		channelz.Infof(logger, cc.channelz, "dial target %q parse failed: %v", canonicalTarget, err)
 		return err
 	}
-	channelz.Infof(logger, cc.channelzID, "parsed dial target is: %+v", parsedTarget)
+	channelz.Infof(logger, cc.channelz, "parsed dial target is: %+v", parsedTarget)
 	rb = cc.getResolver(parsedTarget.URL.Scheme)
 	if rb == nil {
 		return fmt.Errorf("could not get resolver for default scheme: %q", parsedTarget.URL.Scheme)
@@ -1772,6 +1725,8 @@ func parseTarget(target string) (resolver.Target, error) {
 	return resolver.Target{URL: *u}, nil
 }
 
+// encodeAuthority escapes the authority string based on valid chars defined in
+// https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.
 func encodeAuthority(authority string) string {
 	const upperhex = "0123456789ABCDEF"
 
@@ -1860,29 +1815,17 @@ func (cc *ClientConn) determineAuthority() error {
 	}
 
 	endpoint := cc.parsedTarget.Endpoint()
-	target := cc.target
-	switch {
-	case authorityFromDialOption != "":
+	if authorityFromDialOption != "" {
 		cc.authority = authorityFromDialOption
-	case authorityFromCreds != "":
+	} else if authorityFromCreds != "" {
 		cc.authority = authorityFromCreds
-	case strings.HasPrefix(target, "unix:") || strings.HasPrefix(target, "unix-abstract:"):
-		// TODO: remove when the unix resolver implements optional interface to
-		// return channel authority.
-		cc.authority = "localhost"
-	case strings.HasPrefix(endpoint, ":"):
+	} else if auth, ok := cc.resolverBuilder.(resolver.AuthorityOverrider); ok {
+		cc.authority = auth.OverrideAuthority(cc.parsedTarget)
+	} else if strings.HasPrefix(endpoint, ":") {
 		cc.authority = "localhost" + endpoint
-	default:
-		// TODO: Define an optional interface on the resolver builder to return
-		// the channel authority given the user's dial target. For resolvers
-		// which don't implement this interface, we will use the endpoint from
-		// "scheme://authority/endpoint" as the default authority.
-		// Escape the endpoint to handle use cases where the endpoint
-		// might not be a valid authority by default.
-		// For example an endpoint which has multiple paths like
-		// 'a/b/c', which is not a valid authority by default.
+	} else {
 		cc.authority = encodeAuthority(endpoint)
 	}
-	channelz.Infof(logger, cc.channelzID, "Channel authority set to %q", cc.authority)
+	channelz.Infof(logger, cc.channelz, "Channel authority set to %q", cc.authority)
 	return nil
 }