diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/clientconn.go')
-rw-r--r-- | vendor/google.golang.org/grpc/clientconn.go | 518 |
1 files changed, 178 insertions, 340 deletions
diff --git a/vendor/google.golang.org/grpc/clientconn.go b/vendor/google.golang.org/grpc/clientconn.go index 429c389e4..f6e815e6b 100644 --- a/vendor/google.golang.org/grpc/clientconn.go +++ b/vendor/google.golang.org/grpc/clientconn.go @@ -33,9 +33,7 @@ import ( "google.golang.org/grpc/balancer/base" "google.golang.org/grpc/codes" "google.golang.org/grpc/connectivity" - "google.golang.org/grpc/credentials" "google.golang.org/grpc/internal" - "google.golang.org/grpc/internal/backoff" "google.golang.org/grpc/internal/channelz" "google.golang.org/grpc/internal/grpcsync" "google.golang.org/grpc/internal/idle" @@ -48,9 +46,9 @@ import ( "google.golang.org/grpc/status" _ "google.golang.org/grpc/balancer/roundrobin" // To register roundrobin. - _ "google.golang.org/grpc/internal/resolver/dns" // To register dns resolver. _ "google.golang.org/grpc/internal/resolver/passthrough" // To register passthrough resolver. _ "google.golang.org/grpc/internal/resolver/unix" // To register unix resolver. + _ "google.golang.org/grpc/resolver/dns" // To register dns resolver. ) const ( @@ -119,23 +117,8 @@ func (dcs *defaultConfigSelector) SelectConfig(rpcInfo iresolver.RPCInfo) (*ires }, 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. -// -// In the non-blocking case, the ctx does not act against the connection. It -// only controls the setup steps. -// -// 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. -// -// 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. -func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *ClientConn, err error) { +// newClient returns a new client in idle mode. +func newClient(target string, opts ...DialOption) (conn *ClientConn, err error) { cc := &ClientConn{ target: target, conns: make(map[*addrConn]struct{}), @@ -143,23 +126,11 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn * czData: new(channelzData), } - // We start the channel off in idle mode, but kick it out of idle at the end - // of this method, 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, if at all we ever get to do that. - cc.idlenessState = ccIdlenessStateIdle - cc.retryThrottler.Store((*retryThrottler)(nil)) cc.safeConfigSelector.UpdateConfigSelector(&defaultConfigSelector{nil}) cc.ctx, cc.cancel = context.WithCancel(context.Background()) - cc.exitIdleCond = sync.NewCond(&cc.mu) + // Apply dial options. disableGlobalOpts := false for _, opt := range opts { if _, ok := opt.(*disableGlobalDialOptions); ok { @@ -177,21 +148,9 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn * for _, opt := range opts { opt.apply(&cc.dopts) } - chainUnaryClientInterceptors(cc) chainStreamClientInterceptors(cc) - defer func() { - if err != nil { - cc.Close() - } - }() - - // Register ClientConn with channelz. - cc.channelzRegistration(target) - - cc.csMgr = newConnectivityStateManager(cc.ctx, cc.channelzID) - if err := cc.validateTransportCredentials(); err != nil { return nil, err } @@ -205,10 +164,80 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn * } cc.mkp = cc.dopts.copts.KeepaliveParams - if cc.dopts.copts.UserAgent != "" { - cc.dopts.copts.UserAgent += " " + grpcUA - } else { - cc.dopts.copts.UserAgent = grpcUA + // Register ClientConn with channelz. + cc.channelzRegistration(target) + + // TODO: Ideally it should be impossible to error from this function after + // channelz registration. This will require removing some channelz logs + // from the following functions that can error. Errors can be returned to + // the user, and successful logs can be emitted here, after the checks have + // passed and channelz is subsequently registered. + + // Determine the resolver to use. + if err := cc.parseTargetAndFindResolver(); err != nil { + channelz.RemoveEntry(cc.channelzID) + return nil, err + } + if err = cc.determineAuthority(); err != nil { + channelz.RemoveEntry(cc.channelzID) + return nil, err + } + + cc.csMgr = newConnectivityStateManager(cc.ctx, cc.channelzID) + cc.pickerWrapper = newPickerWrapper(cc.dopts.copts.StatsHandlers) + + cc.initIdleStateLocked() // Safe to call without the lock, since nothing else has a reference to cc. + cc.idlenessMgr = idle.NewManager((*idler)(cc), cc.dopts.idleTimeout) + 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. +// +// In the non-blocking case, the ctx does not act against the connection. It +// only controls the setup steps. +// +// 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. +// +// 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. +func DialContext(ctx context.Context, target string, opts ...DialOption) (conn *ClientConn, err error) { + 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. + + defer func() { + if err != nil { + cc.Close() + } + }() + + // This creates the name resolver, load balancer, etc. + if err := cc.idlenessMgr.ExitIdleMode(); err != nil { + return nil, err + } + + // Return now for non-blocking dials. + if !cc.dopts.block { + return cc, nil } if cc.dopts.timeout > 0 { @@ -231,49 +260,6 @@ func DialContext(ctx context.Context, target string, opts ...DialOption) (conn * } }() - if cc.dopts.bs == nil { - cc.dopts.bs = backoff.DefaultExponential - } - - // Determine the resolver to use. - if err := cc.parseTargetAndFindResolver(); err != nil { - return nil, err - } - if err = cc.determineAuthority(); err != nil { - return nil, err - } - - if cc.dopts.scChan != nil { - // Blocking wait for the initial service config. - select { - case sc, ok := <-cc.dopts.scChan: - if ok { - cc.sc = &sc - cc.safeConfigSelector.UpdateConfigSelector(&defaultConfigSelector{&sc}) - } - case <-ctx.Done(): - return nil, ctx.Err() - } - } - if cc.dopts.scChan != nil { - go cc.scWatcher() - } - - // This creates the name resolver, load balancer, blocking picker etc. - if err := cc.exitIdleMode(); err != nil { - return nil, err - } - - // Configure idleness support with configured idle timeout or default idle - // timeout duration. Idleness can be explicitly disabled by the user, by - // setting the dial option to 0. - cc.idlenessMgr = idle.NewManager(idle.ManagerOptions{Enforcer: (*idler)(cc), Timeout: cc.dopts.idleTimeout, Logger: logger}) - - // Return early for non-blocking dials. - if !cc.dopts.block { - return cc, nil - } - // A blocking dial blocks until the clientConn is ready. for { s := cc.GetState() @@ -320,8 +306,8 @@ func (cc *ClientConn) addTraceEvent(msg string) { type idler ClientConn -func (i *idler) EnterIdleMode() error { - return (*ClientConn)(i).enterIdleMode() +func (i *idler) EnterIdleMode() { + (*ClientConn)(i).enterIdleMode() } func (i *idler) ExitIdleMode() error { @@ -329,117 +315,71 @@ func (i *idler) ExitIdleMode() error { } // exitIdleMode moves the channel out of idle mode by recreating the name -// resolver and load balancer. -func (cc *ClientConn) exitIdleMode() error { +// resolver and load balancer. This should never be called directly; use +// cc.idlenessMgr.ExitIdleMode instead. +func (cc *ClientConn) exitIdleMode() (err error) { cc.mu.Lock() if cc.conns == nil { cc.mu.Unlock() return errConnClosing } - if cc.idlenessState != ccIdlenessStateIdle { - channelz.Infof(logger, cc.channelzID, "ClientConn asked to exit idle mode, current mode is %v", cc.idlenessState) - cc.mu.Unlock() - return nil - } - - defer func() { - // When Close() and exitIdleMode() race against each other, one of the - // following two can happen: - // - Close() wins the race and runs first. exitIdleMode() runs after, and - // sees that the ClientConn is already closed and hence returns early. - // - exitIdleMode() wins the race and runs first and recreates the balancer - // and releases the lock before recreating the resolver. If Close() runs - // in this window, it will wait for exitIdleMode to complete. - // - // We achieve this synchronization using the below condition variable. - cc.mu.Lock() - cc.idlenessState = ccIdlenessStateActive - cc.exitIdleCond.Signal() - cc.mu.Unlock() - }() - - cc.idlenessState = ccIdlenessStateExitingIdle - exitedIdle := false - if cc.blockingpicker == nil { - cc.blockingpicker = newPickerWrapper(cc.dopts.copts.StatsHandlers) - } else { - cc.blockingpicker.exitIdleMode() - exitedIdle = true - } - - var credsClone credentials.TransportCredentials - if creds := cc.dopts.copts.TransportCredentials; creds != nil { - credsClone = creds.Clone() - } - if cc.balancerWrapper == nil { - cc.balancerWrapper = newCCBalancerWrapper(cc, balancer.BuildOptions{ - DialCreds: credsClone, - CredsBundle: cc.dopts.copts.CredsBundle, - Dialer: cc.dopts.copts.Dialer, - Authority: cc.authority, - CustomUserAgent: cc.dopts.copts.UserAgent, - ChannelzParentID: cc.channelzID, - Target: cc.parsedTarget, - }) - } else { - cc.balancerWrapper.exitIdleMode() - } - cc.firstResolveEvent = grpcsync.NewEvent() cc.mu.Unlock() // This needs to be called without cc.mu because this builds a new resolver - // which might update state or report error inline which needs to be handled - // by cc.updateResolverState() which also grabs cc.mu. - if err := cc.initResolverWrapper(credsClone); err != nil { + // which might update state or report error inline, which would then need to + // acquire cc.mu. + if err := cc.resolverWrapper.start(); err != nil { return err } - if exitedIdle { - cc.addTraceEvent("exiting idle mode") - } + cc.addTraceEvent("exiting idle mode") return nil } +// initIdleStateLocked initializes common state to how it should be while idle. +func (cc *ClientConn) initIdleStateLocked() { + cc.resolverWrapper = newCCResolverWrapper(cc) + cc.balancerWrapper = newCCBalancerWrapper(cc) + cc.firstResolveEvent = grpcsync.NewEvent() + // cc.conns == nil is a proxy for the ClientConn being closed. So, instead + // of setting it to nil here, we recreate the map. This also means that we + // don't have to do this when exiting idle mode. + cc.conns = make(map[*addrConn]struct{}) +} + // enterIdleMode puts the channel in idle mode, and as part of it shuts down the -// name resolver, load balancer and any subchannels. -func (cc *ClientConn) enterIdleMode() error { +// name resolver, load balancer, and any subchannels. This should never be +// called directly; use cc.idlenessMgr.EnterIdleMode instead. +func (cc *ClientConn) enterIdleMode() { cc.mu.Lock() - defer cc.mu.Unlock() if cc.conns == nil { - return ErrClientConnClosing - } - if cc.idlenessState != ccIdlenessStateActive { - channelz.Warningf(logger, cc.channelzID, "ClientConn asked to enter idle mode, current mode is %v", cc.idlenessState) - return nil + cc.mu.Unlock() + return } - // cc.conns == nil is a proxy for the ClientConn being closed. So, instead - // of setting it to nil here, we recreate the map. This also means that we - // don't have to do this when exiting idle mode. conns := cc.conns - cc.conns = make(map[*addrConn]struct{}) - // TODO: Currently, we close the resolver wrapper upon entering idle mode - // and create a new one upon exiting idle mode. This means that the - // `cc.resolverWrapper` field would be overwritten everytime we exit idle - // mode. While this means that we need to hold `cc.mu` when accessing - // `cc.resolverWrapper`, it makes the code simpler in the wrapper. We should - // try to do the same for the balancer and picker wrappers too. - cc.resolverWrapper.close() - cc.blockingpicker.enterIdleMode() - cc.balancerWrapper.enterIdleMode() + rWrapper := cc.resolverWrapper + rWrapper.close() + cc.pickerWrapper.reset() + bWrapper := cc.balancerWrapper + bWrapper.close() cc.csMgr.updateState(connectivity.Idle) - cc.idlenessState = ccIdlenessStateIdle cc.addTraceEvent("entering idle mode") - go func() { - for ac := range conns { - ac.tearDown(errConnIdling) - } - }() + cc.initIdleStateLocked() - return nil + cc.mu.Unlock() + + // Block until the name resolver and LB policy are closed. + <-rWrapper.serializer.Done() + <-bWrapper.serializer.Done() + + // Close all subchannels after the LB policy is closed. + for ac := range conns { + ac.tearDown(errConnIdling) + } } // validateTransportCredentials performs a series of checks on the configured @@ -649,66 +589,35 @@ type ClientConn struct { dopts dialOptions // Default and user specified dial options. channelzID *channelz.Identifier // Channelz identifier for the channel. resolverBuilder resolver.Builder // See parseTargetAndFindResolver(). - balancerWrapper *ccBalancerWrapper // Uses gracefulswitch.balancer underneath. - idlenessMgr idle.Manager + idlenessMgr *idle.Manager // The following provide their own synchronization, and therefore don't // require cc.mu to be held to access them. csMgr *connectivityStateManager - blockingpicker *pickerWrapper + pickerWrapper *pickerWrapper safeConfigSelector iresolver.SafeConfigSelector czData *channelzData retryThrottler atomic.Value // Updated from service config. - // firstResolveEvent is used to track whether the name resolver sent us at - // least one update. RPCs block on this event. - firstResolveEvent *grpcsync.Event - // mu protects the following fields. // TODO: split mu so the same mutex isn't used for everything. mu sync.RWMutex - resolverWrapper *ccResolverWrapper // Initialized in Dial; cleared in Close. + resolverWrapper *ccResolverWrapper // Always recreated whenever entering idle to simplify Close. + balancerWrapper *ccBalancerWrapper // Always recreated whenever entering idle to simplify Close. sc *ServiceConfig // Latest service config received from the resolver. conns map[*addrConn]struct{} // Set to nil on close. mkp keepalive.ClientParameters // May be updated upon receipt of a GoAway. - idlenessState ccIdlenessState // Tracks idleness state of the channel. - exitIdleCond *sync.Cond // Signalled when channel exits idle. + // firstResolveEvent is used to track whether the name resolver sent us at + // least one update. RPCs block on this event. May be accessed without mu + // if we know we cannot be asked to enter idle mode while accessing it (e.g. + // when the idle manager has already been closed, or if we are already + // entering idle mode). + firstResolveEvent *grpcsync.Event lceMu sync.Mutex // protects lastConnectionError lastConnectionError error } -// ccIdlenessState tracks the idleness state of the channel. -// -// Channels start off in `active` and move to `idle` after a period of -// inactivity. When moving back to `active` upon an incoming RPC, they -// transition through `exiting_idle`. This state is useful for synchronization -// with Close(). -// -// This state tracking is mostly for self-protection. The idlenessManager is -// expected to keep track of the state as well, and is expected not to call into -// the ClientConn unnecessarily. -type ccIdlenessState int8 - -const ( - ccIdlenessStateActive ccIdlenessState = iota - ccIdlenessStateIdle - ccIdlenessStateExitingIdle -) - -func (s ccIdlenessState) String() string { - switch s { - case ccIdlenessStateActive: - return "active" - case ccIdlenessStateIdle: - return "idle" - case ccIdlenessStateExitingIdle: - return "exitingIdle" - default: - return "unknown" - } -} - // WaitForStateChange waits until the connectivity.State of ClientConn changes from sourceState or // ctx expires. A true value is returned in former case and false in latter. // @@ -748,29 +657,15 @@ func (cc *ClientConn) GetState() connectivity.State { // Notice: This API is EXPERIMENTAL and may be changed or removed in a later // release. func (cc *ClientConn) Connect() { - cc.exitIdleMode() + if err := cc.idlenessMgr.ExitIdleMode(); err != nil { + cc.addTraceEvent(err.Error()) + return + } // If the ClientConn was not in idle mode, we need to call ExitIdle on the // LB policy so that connections can be created. - cc.balancerWrapper.exitIdleMode() -} - -func (cc *ClientConn) scWatcher() { - for { - select { - case sc, ok := <-cc.dopts.scChan: - if !ok { - return - } - cc.mu.Lock() - // TODO: load balance policy runtime change is ignored. - // We may revisit this decision in the future. - cc.sc = &sc - cc.safeConfigSelector.UpdateConfigSelector(&defaultConfigSelector{&sc}) - cc.mu.Unlock() - case <-cc.ctx.Done(): - return - } - } + cc.mu.Lock() + cc.balancerWrapper.exitIdle() + cc.mu.Unlock() } // waitForResolvedAddrs blocks until the resolver has provided addresses or the @@ -804,11 +699,11 @@ func init() { internal.SubscribeToConnectivityStateChanges = func(cc *ClientConn, s grpcsync.Subscriber) func() { return cc.csMgr.pubSub.Subscribe(s) } - internal.EnterIdleModeForTesting = func(cc *ClientConn) error { - return cc.enterIdleMode() + internal.EnterIdleModeForTesting = func(cc *ClientConn) { + cc.idlenessMgr.EnterIdleModeForTesting() } internal.ExitIdleModeForTesting = func(cc *ClientConn) error { - return cc.exitIdleMode() + return cc.idlenessMgr.ExitIdleMode() } } @@ -824,9 +719,8 @@ func (cc *ClientConn) maybeApplyDefaultServiceConfig(addrs []resolver.Address) { } } -func (cc *ClientConn) updateResolverState(s resolver.State, err error) error { +func (cc *ClientConn) updateResolverStateAndUnlock(s resolver.State, err error) error { defer cc.firstResolveEvent.Fire() - cc.mu.Lock() // Check if the ClientConn is already closed. Some fields (e.g. // balancerWrapper) are set to nil when closing the ClientConn, and could // cause nil pointer panic if we don't have this check. @@ -872,7 +766,7 @@ func (cc *ClientConn) updateResolverState(s resolver.State, err error) error { if cc.sc == nil { // Apply the failing LB only if we haven't received valid service config // from the name resolver in the past. - cc.applyFailingLB(s.ServiceConfig) + cc.applyFailingLBLocked(s.ServiceConfig) cc.mu.Unlock() return ret } @@ -894,15 +788,13 @@ func (cc *ClientConn) updateResolverState(s resolver.State, err error) error { return ret } -// applyFailingLB is akin to configuring an LB policy on the channel which +// applyFailingLBLocked is akin to configuring an LB policy on the channel which // always fails RPCs. Here, an actual LB policy is not configured, but an always // erroring picker is configured, which returns errors with information about // what was invalid in the received service config. A config selector with no // service config is configured, and the connectivity state of the channel is // set to TransientFailure. -// -// Caller must hold cc.mu. -func (cc *ClientConn) applyFailingLB(sc *serviceconfig.ParseResult) { +func (cc *ClientConn) applyFailingLBLocked(sc *serviceconfig.ParseResult) { var err error if sc.Err != nil { err = status.Errorf(codes.Unavailable, "error parsing service config: %v", sc.Err) @@ -910,14 +802,10 @@ func (cc *ClientConn) applyFailingLB(sc *serviceconfig.ParseResult) { err = status.Errorf(codes.Unavailable, "illegal service config type: %T", sc.Config) } cc.safeConfigSelector.UpdateConfigSelector(&defaultConfigSelector{nil}) - cc.blockingpicker.updatePicker(base.NewErrPicker(err)) + cc.pickerWrapper.updatePicker(base.NewErrPicker(err)) cc.csMgr.updateState(connectivity.TransientFailure) } -func (cc *ClientConn) handleSubConnStateChange(sc balancer.SubConn, s connectivity.State, err error) { - cc.balancerWrapper.updateSubConnState(sc, s, err) -} - // Makes a copy of the input addresses slice and clears out the balancer // attributes field. Addresses are passed during subconn creation and address // update operations. In both cases, we will clear the balancer attributes by @@ -932,10 +820,14 @@ func copyAddressesWithoutBalancerAttributes(in []resolver.Address) []resolver.Ad return out } -// newAddrConn creates an addrConn for addrs and adds it to cc.conns. +// newAddrConnLocked creates an addrConn for addrs and adds it to cc.conns. // // Caller needs to make sure len(addrs) > 0. -func (cc *ClientConn) newAddrConn(addrs []resolver.Address, opts balancer.NewSubConnOptions) (*addrConn, error) { +func (cc *ClientConn) newAddrConnLocked(addrs []resolver.Address, opts balancer.NewSubConnOptions) (*addrConn, error) { + if cc.conns == nil { + return nil, ErrClientConnClosing + } + ac := &addrConn{ state: connectivity.Idle, cc: cc, @@ -947,12 +839,6 @@ func (cc *ClientConn) newAddrConn(addrs []resolver.Address, opts balancer.NewSub stateChan: make(chan struct{}), } ac.ctx, ac.cancel = context.WithCancel(cc.ctx) - // Track ac in cc. This needs to be done before any getTransport(...) is called. - cc.mu.Lock() - defer cc.mu.Unlock() - if cc.conns == nil { - return nil, ErrClientConnClosing - } var err error ac.channelzID, err = channelz.RegisterSubChannel(ac, cc.channelzID, "") @@ -968,6 +854,7 @@ func (cc *ClientConn) newAddrConn(addrs []resolver.Address, opts balancer.NewSub }, }) + // Track ac in cc. This needs to be done before any getTransport(...) is called. cc.conns[ac] = struct{}{} return ac, nil } @@ -1174,7 +1061,7 @@ func (cc *ClientConn) healthCheckConfig() *healthCheckConfig { } func (cc *ClientConn) getTransport(ctx context.Context, failfast bool, method string) (transport.ClientTransport, balancer.PickResult, error) { - return cc.blockingpicker.pick(ctx, failfast, balancer.PickInfo{ + return cc.pickerWrapper.pick(ctx, failfast, balancer.PickInfo{ Ctx: ctx, FullMethodName: method, }) @@ -1216,12 +1103,12 @@ func (cc *ClientConn) applyServiceConfigAndBalancer(sc *ServiceConfig, configSel func (cc *ClientConn) resolveNow(o resolver.ResolveNowOptions) { cc.mu.RLock() - r := cc.resolverWrapper + cc.resolverWrapper.resolveNow(o) cc.mu.RUnlock() - if r == nil { - return - } - go r.resolveNow(o) +} + +func (cc *ClientConn) resolveNowLocked(o resolver.ResolveNowOptions) { + cc.resolverWrapper.resolveNow(o) } // ResetConnectBackoff wakes up all subchannels in transient failure and causes @@ -1253,40 +1140,32 @@ func (cc *ClientConn) Close() error { <-cc.csMgr.pubSub.Done() }() + // Prevent calls to enter/exit idle immediately, and ensure we are not + // currently entering/exiting idle mode. + cc.idlenessMgr.Close() + cc.mu.Lock() if cc.conns == nil { cc.mu.Unlock() return ErrClientConnClosing } - for cc.idlenessState == ccIdlenessStateExitingIdle { - cc.exitIdleCond.Wait() - } - conns := cc.conns cc.conns = nil cc.csMgr.updateState(connectivity.Shutdown) - pWrapper := cc.blockingpicker - rWrapper := cc.resolverWrapper - bWrapper := cc.balancerWrapper - idlenessMgr := cc.idlenessMgr + // We can safely unlock and continue to access all fields now as + // cc.conns==nil, preventing any further operations on cc. cc.mu.Unlock() + cc.resolverWrapper.close() // The order of closing matters here since the balancer wrapper assumes the // picker is closed before it is closed. - if pWrapper != nil { - pWrapper.close() - } - if bWrapper != nil { - bWrapper.close() - } - if rWrapper != nil { - rWrapper.close() - } - if idlenessMgr != nil { - idlenessMgr.Close() - } + cc.pickerWrapper.close() + cc.balancerWrapper.close() + + <-cc.resolverWrapper.serializer.Done() + <-cc.balancerWrapper.serializer.Done() for ac := range conns { ac.tearDown(ErrClientConnClosing) @@ -1307,7 +1186,7 @@ type addrConn struct { cc *ClientConn dopts dialOptions - acbw balancer.SubConn + acbw *acBalancerWrapper scopts balancer.NewSubConnOptions // transport is set when there's a viable transport (note: ac state may not be READY as LB channel @@ -1345,7 +1224,7 @@ func (ac *addrConn) updateConnectivityState(s connectivity.State, lastErr error) } else { channelz.Infof(logger, ac.channelzID, "Subchannel Connectivity change to %v, last error: %s", s, lastErr) } - ac.cc.handleSubConnStateChange(ac.acbw, s, lastErr) + ac.acbw.updateState(s, lastErr) } // adjustParams updates parameters used to create transports upon @@ -1849,7 +1728,7 @@ func (cc *ClientConn) parseTargetAndFindResolver() error { if err != nil { channelz.Infof(logger, cc.channelzID, "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.channelzID, "parsed dial target is: %#v", parsedTarget) rb = cc.getResolver(parsedTarget.URL.Scheme) if rb != nil { cc.parsedTarget = parsedTarget @@ -1981,58 +1860,17 @@ 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) return nil } - -// initResolverWrapper creates a ccResolverWrapper, which builds the name -// resolver. This method grabs the lock to assign the newly built resolver -// wrapper to the cc.resolverWrapper field. -func (cc *ClientConn) initResolverWrapper(creds credentials.TransportCredentials) error { - rw, err := newCCResolverWrapper(cc, ccResolverWrapperOpts{ - target: cc.parsedTarget, - builder: cc.resolverBuilder, - bOpts: resolver.BuildOptions{ - DisableServiceConfig: cc.dopts.disableServiceConfig, - DialCreds: creds, - CredsBundle: cc.dopts.copts.CredsBundle, - Dialer: cc.dopts.copts.Dialer, - }, - channelzID: cc.channelzID, - }) - if err != nil { - return fmt.Errorf("failed to build resolver: %v", err) - } - // Resolver implementations may report state update or error inline when - // built (or right after), and this is handled in cc.updateResolverState. - // Also, an error from the resolver might lead to a re-resolution request - // from the balancer, which is handled in resolveNow() where - // `cc.resolverWrapper` is accessed. Hence, we need to hold the lock here. - cc.mu.Lock() - cc.resolverWrapper = rw - cc.mu.Unlock() - return nil -} |