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-rw-r--r--vendor/google.golang.org/grpc/clientconn.go1602
1 files changed, 0 insertions, 1602 deletions
diff --git a/vendor/google.golang.org/grpc/clientconn.go b/vendor/google.golang.org/grpc/clientconn.go
deleted file mode 100644
index 84ba9e5ad..000000000
--- a/vendor/google.golang.org/grpc/clientconn.go
+++ /dev/null
@@ -1,1602 +0,0 @@
-/*
- *
- * Copyright 2014 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 grpc
-
-import (
- "errors"
- "fmt"
- "math"
- "net"
- "reflect"
- "strings"
- "sync"
- "time"
-
- "golang.org/x/net/context"
- "golang.org/x/net/trace"
- "google.golang.org/grpc/balancer"
- _ "google.golang.org/grpc/balancer/roundrobin" // To register roundrobin.
- "google.golang.org/grpc/codes"
- "google.golang.org/grpc/connectivity"
- "google.golang.org/grpc/credentials"
- "google.golang.org/grpc/grpclog"
- "google.golang.org/grpc/internal"
- "google.golang.org/grpc/internal/backoff"
- "google.golang.org/grpc/internal/channelz"
- "google.golang.org/grpc/keepalive"
- "google.golang.org/grpc/resolver"
- _ "google.golang.org/grpc/resolver/dns" // To register dns resolver.
- _ "google.golang.org/grpc/resolver/passthrough" // To register passthrough resolver.
- "google.golang.org/grpc/stats"
- "google.golang.org/grpc/status"
- "google.golang.org/grpc/transport"
-)
-
-const (
- // minimum time to give a connection to complete
- minConnectTimeout = 20 * time.Second
- // must match grpclbName in grpclb/grpclb.go
- grpclbName = "grpclb"
-)
-
-var (
- // ErrClientConnClosing indicates that the operation is illegal because
- // the ClientConn is closing.
- //
- // Deprecated: this error should not be relied upon by users; use the status
- // code of Canceled instead.
- ErrClientConnClosing = status.Error(codes.Canceled, "grpc: the client connection is closing")
- // errConnDrain indicates that the connection starts to be drained and does not accept any new RPCs.
- errConnDrain = errors.New("grpc: the connection is drained")
- // errConnClosing indicates that the connection is closing.
- errConnClosing = errors.New("grpc: the connection is closing")
- // errConnUnavailable indicates that the connection is unavailable.
- errConnUnavailable = errors.New("grpc: the connection is unavailable")
- // errBalancerClosed indicates that the balancer is closed.
- errBalancerClosed = errors.New("grpc: balancer is closed")
- // We use an accessor so that minConnectTimeout can be
- // atomically read and updated while testing.
- getMinConnectTimeout = func() time.Duration {
- return minConnectTimeout
- }
-)
-
-// The following errors are returned from Dial and DialContext
-var (
- // errNoTransportSecurity indicates that there is no transport security
- // being set for ClientConn. Users should either set one or explicitly
- // call WithInsecure DialOption to disable security.
- errNoTransportSecurity = errors.New("grpc: no transport security set (use grpc.WithInsecure() explicitly or set credentials)")
- // errTransportCredentialsMissing indicates that users want to transmit security
- // information (e.g., oauth2 token) which requires secure connection on an insecure
- // connection.
- errTransportCredentialsMissing = errors.New("grpc: the credentials require transport level security (use grpc.WithTransportCredentials() to set)")
- // errCredentialsConflict indicates that grpc.WithTransportCredentials()
- // and grpc.WithInsecure() are both called for a connection.
- errCredentialsConflict = errors.New("grpc: transport credentials are set for an insecure connection (grpc.WithTransportCredentials() and grpc.WithInsecure() are both called)")
- // errNetworkIO indicates that the connection is down due to some network I/O error.
- errNetworkIO = errors.New("grpc: failed with network I/O error")
-)
-
-// dialOptions configure a Dial call. dialOptions are set by the DialOption
-// values passed to Dial.
-type dialOptions struct {
- unaryInt UnaryClientInterceptor
- streamInt StreamClientInterceptor
- cp Compressor
- dc Decompressor
- bs backoff.Strategy
- block bool
- insecure bool
- timeout time.Duration
- scChan <-chan ServiceConfig
- copts transport.ConnectOptions
- callOptions []CallOption
- // This is used by v1 balancer dial option WithBalancer to support v1
- // balancer, and also by WithBalancerName dial option.
- balancerBuilder balancer.Builder
- // This is to support grpclb.
- resolverBuilder resolver.Builder
- waitForHandshake bool
- channelzParentID int64
- disableServiceConfig bool
-}
-
-const (
- defaultClientMaxReceiveMessageSize = 1024 * 1024 * 4
- defaultClientMaxSendMessageSize = math.MaxInt32
-)
-
-// RegisterChannelz turns on channelz service.
-// This is an EXPERIMENTAL API.
-func RegisterChannelz() {
- channelz.TurnOn()
-}
-
-// DialOption configures how we set up the connection.
-type DialOption func(*dialOptions)
-
-// WithWaitForHandshake blocks until the initial settings frame is received from the
-// server before assigning RPCs to the connection.
-// Experimental API.
-func WithWaitForHandshake() DialOption {
- return func(o *dialOptions) {
- o.waitForHandshake = true
- }
-}
-
-// WithWriteBufferSize lets you set the size of write buffer, this determines how much data can be batched
-// before doing a write on the wire.
-func WithWriteBufferSize(s int) DialOption {
- return func(o *dialOptions) {
- o.copts.WriteBufferSize = s
- }
-}
-
-// WithReadBufferSize lets you set the size of read buffer, this determines how much data can be read at most
-// for each read syscall.
-func WithReadBufferSize(s int) DialOption {
- return func(o *dialOptions) {
- o.copts.ReadBufferSize = s
- }
-}
-
-// WithInitialWindowSize returns a DialOption which sets the value for initial window size on a stream.
-// The lower bound for window size is 64K and any value smaller than that will be ignored.
-func WithInitialWindowSize(s int32) DialOption {
- return func(o *dialOptions) {
- o.copts.InitialWindowSize = s
- }
-}
-
-// WithInitialConnWindowSize returns a DialOption which sets the value for initial window size on a connection.
-// The lower bound for window size is 64K and any value smaller than that will be ignored.
-func WithInitialConnWindowSize(s int32) DialOption {
- return func(o *dialOptions) {
- o.copts.InitialConnWindowSize = s
- }
-}
-
-// WithMaxMsgSize returns a DialOption which sets the maximum message size the client can receive.
-//
-// Deprecated: use WithDefaultCallOptions(MaxCallRecvMsgSize(s)) instead.
-func WithMaxMsgSize(s int) DialOption {
- return WithDefaultCallOptions(MaxCallRecvMsgSize(s))
-}
-
-// WithDefaultCallOptions returns a DialOption which sets the default CallOptions for calls over the connection.
-func WithDefaultCallOptions(cos ...CallOption) DialOption {
- return func(o *dialOptions) {
- o.callOptions = append(o.callOptions, cos...)
- }
-}
-
-// WithCodec returns a DialOption which sets a codec for message marshaling and unmarshaling.
-//
-// Deprecated: use WithDefaultCallOptions(CallCustomCodec(c)) instead.
-func WithCodec(c Codec) DialOption {
- return WithDefaultCallOptions(CallCustomCodec(c))
-}
-
-// WithCompressor returns a DialOption which sets a Compressor to use for
-// message compression. It has lower priority than the compressor set by
-// the UseCompressor CallOption.
-//
-// Deprecated: use UseCompressor instead.
-func WithCompressor(cp Compressor) DialOption {
- return func(o *dialOptions) {
- o.cp = cp
- }
-}
-
-// WithDecompressor returns a DialOption which sets a Decompressor to use for
-// incoming message decompression. If incoming response messages are encoded
-// using the decompressor's Type(), it will be used. Otherwise, the message
-// encoding will be used to look up the compressor registered via
-// encoding.RegisterCompressor, which will then be used to decompress the
-// message. If no compressor is registered for the encoding, an Unimplemented
-// status error will be returned.
-//
-// Deprecated: use encoding.RegisterCompressor instead.
-func WithDecompressor(dc Decompressor) DialOption {
- return func(o *dialOptions) {
- o.dc = dc
- }
-}
-
-// WithBalancer returns a DialOption which sets a load balancer with the v1 API.
-// Name resolver will be ignored if this DialOption is specified.
-//
-// Deprecated: use the new balancer APIs in balancer package and WithBalancerName.
-func WithBalancer(b Balancer) DialOption {
- return func(o *dialOptions) {
- o.balancerBuilder = &balancerWrapperBuilder{
- b: b,
- }
- }
-}
-
-// WithBalancerName sets the balancer that the ClientConn will be initialized
-// with. Balancer registered with balancerName will be used. This function
-// panics if no balancer was registered by balancerName.
-//
-// The balancer cannot be overridden by balancer option specified by service
-// config.
-//
-// This is an EXPERIMENTAL API.
-func WithBalancerName(balancerName string) DialOption {
- builder := balancer.Get(balancerName)
- if builder == nil {
- panic(fmt.Sprintf("grpc.WithBalancerName: no balancer is registered for name %v", balancerName))
- }
- return func(o *dialOptions) {
- o.balancerBuilder = builder
- }
-}
-
-// withResolverBuilder is only for grpclb.
-func withResolverBuilder(b resolver.Builder) DialOption {
- return func(o *dialOptions) {
- o.resolverBuilder = b
- }
-}
-
-// WithServiceConfig returns a DialOption which has a channel to read the service configuration.
-//
-// Deprecated: service config should be received through name resolver, as specified here.
-// https://github.com/grpc/grpc/blob/master/doc/service_config.md
-func WithServiceConfig(c <-chan ServiceConfig) DialOption {
- return func(o *dialOptions) {
- o.scChan = c
- }
-}
-
-// WithBackoffMaxDelay configures the dialer to use the provided maximum delay
-// when backing off after failed connection attempts.
-func WithBackoffMaxDelay(md time.Duration) DialOption {
- return WithBackoffConfig(BackoffConfig{MaxDelay: md})
-}
-
-// WithBackoffConfig configures the dialer to use the provided backoff
-// parameters after connection failures.
-//
-// Use WithBackoffMaxDelay until more parameters on BackoffConfig are opened up
-// for use.
-func WithBackoffConfig(b BackoffConfig) DialOption {
-
- return withBackoff(backoff.Exponential{
- MaxDelay: b.MaxDelay,
- })
-}
-
-// withBackoff sets the backoff strategy used for connectRetryNum after a
-// failed connection attempt.
-//
-// This can be exported if arbitrary backoff strategies are allowed by gRPC.
-func withBackoff(bs backoff.Strategy) DialOption {
- return func(o *dialOptions) {
- o.bs = bs
- }
-}
-
-// WithBlock returns a DialOption which makes caller of Dial blocks until the underlying
-// connection is up. Without this, Dial returns immediately and connecting the server
-// happens in background.
-func WithBlock() DialOption {
- return func(o *dialOptions) {
- o.block = true
- }
-}
-
-// WithInsecure returns a DialOption which disables transport security for this ClientConn.
-// Note that transport security is required unless WithInsecure is set.
-func WithInsecure() DialOption {
- return func(o *dialOptions) {
- o.insecure = true
- }
-}
-
-// WithTransportCredentials returns a DialOption which configures a
-// connection level security credentials (e.g., TLS/SSL).
-func WithTransportCredentials(creds credentials.TransportCredentials) DialOption {
- return func(o *dialOptions) {
- o.copts.TransportCredentials = creds
- }
-}
-
-// WithPerRPCCredentials returns a DialOption which sets
-// credentials and places auth state on each outbound RPC.
-func WithPerRPCCredentials(creds credentials.PerRPCCredentials) DialOption {
- return func(o *dialOptions) {
- o.copts.PerRPCCredentials = append(o.copts.PerRPCCredentials, creds)
- }
-}
-
-// WithTimeout returns a DialOption that configures a timeout for dialing a ClientConn
-// initially. This is valid if and only if WithBlock() is present.
-//
-// Deprecated: use DialContext and context.WithTimeout instead.
-func WithTimeout(d time.Duration) DialOption {
- return func(o *dialOptions) {
- o.timeout = d
- }
-}
-
-func withContextDialer(f func(context.Context, string) (net.Conn, error)) DialOption {
- return func(o *dialOptions) {
- o.copts.Dialer = f
- }
-}
-
-func init() {
- internal.WithContextDialer = withContextDialer
- internal.WithResolverBuilder = withResolverBuilder
-}
-
-// WithDialer returns a DialOption that specifies a function to use for dialing network addresses.
-// If FailOnNonTempDialError() is set to true, and an error is returned by f, gRPC checks the error's
-// Temporary() method to decide if it should try to reconnect to the network address.
-func WithDialer(f func(string, time.Duration) (net.Conn, error)) DialOption {
- return withContextDialer(
- func(ctx context.Context, addr string) (net.Conn, error) {
- if deadline, ok := ctx.Deadline(); ok {
- return f(addr, deadline.Sub(time.Now()))
- }
- return f(addr, 0)
- })
-}
-
-// WithStatsHandler returns a DialOption that specifies the stats handler
-// for all the RPCs and underlying network connections in this ClientConn.
-func WithStatsHandler(h stats.Handler) DialOption {
- return func(o *dialOptions) {
- o.copts.StatsHandler = h
- }
-}
-
-// FailOnNonTempDialError returns a DialOption that specifies if gRPC fails on non-temporary dial errors.
-// If f is true, and dialer returns a non-temporary error, gRPC will fail the connection to the network
-// address and won't try to reconnect.
-// The default value of FailOnNonTempDialError is false.
-// This is an EXPERIMENTAL API.
-func FailOnNonTempDialError(f bool) DialOption {
- return func(o *dialOptions) {
- o.copts.FailOnNonTempDialError = f
- }
-}
-
-// WithUserAgent returns a DialOption that specifies a user agent string for all the RPCs.
-func WithUserAgent(s string) DialOption {
- return func(o *dialOptions) {
- o.copts.UserAgent = s
- }
-}
-
-// WithKeepaliveParams returns a DialOption that specifies keepalive parameters for the client transport.
-func WithKeepaliveParams(kp keepalive.ClientParameters) DialOption {
- return func(o *dialOptions) {
- o.copts.KeepaliveParams = kp
- }
-}
-
-// WithUnaryInterceptor returns a DialOption that specifies the interceptor for unary RPCs.
-func WithUnaryInterceptor(f UnaryClientInterceptor) DialOption {
- return func(o *dialOptions) {
- o.unaryInt = f
- }
-}
-
-// WithStreamInterceptor returns a DialOption that specifies the interceptor for streaming RPCs.
-func WithStreamInterceptor(f StreamClientInterceptor) DialOption {
- return func(o *dialOptions) {
- o.streamInt = f
- }
-}
-
-// WithAuthority returns a DialOption that specifies the value to be used as
-// the :authority pseudo-header. This value only works with WithInsecure and
-// has no effect if TransportCredentials are present.
-func WithAuthority(a string) DialOption {
- return func(o *dialOptions) {
- o.copts.Authority = a
- }
-}
-
-// WithChannelzParentID returns a DialOption that specifies the channelz ID of current ClientConn's
-// parent. This function is used in nested channel creation (e.g. grpclb dial).
-func WithChannelzParentID(id int64) DialOption {
- return func(o *dialOptions) {
- o.channelzParentID = id
- }
-}
-
-// WithDisableServiceConfig returns a DialOption that causes grpc to ignore any
-// service config provided by the resolver and provides a hint to the resolver
-// to not fetch service configs.
-func WithDisableServiceConfig() DialOption {
- return func(o *dialOptions) {
- o.disableServiceConfig = true
- }
-}
-
-// Dial creates a client connection to the given target.
-func Dial(target string, opts ...DialOption) (*ClientConn, error) {
- return DialContext(context.Background(), target, opts...)
-}
-
-// 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 := &ClientConn{
- target: target,
- csMgr: &connectivityStateManager{},
- conns: make(map[*addrConn]struct{}),
-
- blockingpicker: newPickerWrapper(),
- }
- cc.ctx, cc.cancel = context.WithCancel(context.Background())
-
- for _, opt := range opts {
- opt(&cc.dopts)
- }
-
- if channelz.IsOn() {
- if cc.dopts.channelzParentID != 0 {
- cc.channelzID = channelz.RegisterChannel(cc, cc.dopts.channelzParentID, target)
- } else {
- cc.channelzID = channelz.RegisterChannel(cc, 0, target)
- }
- }
-
- if !cc.dopts.insecure {
- if cc.dopts.copts.TransportCredentials == nil {
- return nil, errNoTransportSecurity
- }
- } else {
- if cc.dopts.copts.TransportCredentials != nil {
- return nil, errCredentialsConflict
- }
- for _, cd := range cc.dopts.copts.PerRPCCredentials {
- if cd.RequireTransportSecurity() {
- return nil, errTransportCredentialsMissing
- }
- }
- }
-
- cc.mkp = cc.dopts.copts.KeepaliveParams
-
- if cc.dopts.copts.Dialer == nil {
- cc.dopts.copts.Dialer = newProxyDialer(
- func(ctx context.Context, addr string) (net.Conn, error) {
- network, addr := parseDialTarget(addr)
- return dialContext(ctx, network, addr)
- },
- )
- }
-
- if cc.dopts.copts.UserAgent != "" {
- cc.dopts.copts.UserAgent += " " + grpcUA
- } else {
- cc.dopts.copts.UserAgent = grpcUA
- }
-
- if cc.dopts.timeout > 0 {
- var cancel context.CancelFunc
- ctx, cancel = context.WithTimeout(ctx, cc.dopts.timeout)
- defer cancel()
- }
-
- defer func() {
- select {
- case <-ctx.Done():
- conn, err = nil, ctx.Err()
- default:
- }
-
- if err != nil {
- cc.Close()
- }
- }()
-
- scSet := false
- if cc.dopts.scChan != nil {
- // Try to get an initial service config.
- select {
- case sc, ok := <-cc.dopts.scChan:
- if ok {
- cc.sc = sc
- scSet = true
- }
- default:
- }
- }
- if cc.dopts.bs == nil {
- cc.dopts.bs = backoff.Exponential{
- MaxDelay: DefaultBackoffConfig.MaxDelay,
- }
- }
- if cc.dopts.resolverBuilder == nil {
- // Only try to parse target when resolver builder is not already set.
- cc.parsedTarget = parseTarget(cc.target)
- grpclog.Infof("parsed scheme: %q", cc.parsedTarget.Scheme)
- cc.dopts.resolverBuilder = resolver.Get(cc.parsedTarget.Scheme)
- if cc.dopts.resolverBuilder == nil {
- // If resolver builder is still nil, the parse target's scheme is
- // not registered. Fallback to default resolver and set Endpoint to
- // the original unparsed target.
- grpclog.Infof("scheme %q not registered, fallback to default scheme", cc.parsedTarget.Scheme)
- cc.parsedTarget = resolver.Target{
- Scheme: resolver.GetDefaultScheme(),
- Endpoint: target,
- }
- cc.dopts.resolverBuilder = resolver.Get(cc.parsedTarget.Scheme)
- }
- } else {
- cc.parsedTarget = resolver.Target{Endpoint: target}
- }
- creds := cc.dopts.copts.TransportCredentials
- if creds != nil && creds.Info().ServerName != "" {
- cc.authority = creds.Info().ServerName
- } else if cc.dopts.insecure && cc.dopts.copts.Authority != "" {
- cc.authority = cc.dopts.copts.Authority
- } else {
- // Use endpoint from "scheme://authority/endpoint" as the default
- // authority for ClientConn.
- cc.authority = cc.parsedTarget.Endpoint
- }
-
- if cc.dopts.scChan != nil && !scSet {
- // Blocking wait for the initial service config.
- select {
- case sc, ok := <-cc.dopts.scChan:
- if ok {
- cc.sc = sc
- }
- case <-ctx.Done():
- return nil, ctx.Err()
- }
- }
- if cc.dopts.scChan != nil {
- go cc.scWatcher()
- }
-
- var credsClone credentials.TransportCredentials
- if creds := cc.dopts.copts.TransportCredentials; creds != nil {
- credsClone = creds.Clone()
- }
- cc.balancerBuildOpts = balancer.BuildOptions{
- DialCreds: credsClone,
- Dialer: cc.dopts.copts.Dialer,
- ChannelzParentID: cc.channelzID,
- }
-
- // Build the resolver.
- cc.resolverWrapper, err = newCCResolverWrapper(cc)
- if err != nil {
- return nil, fmt.Errorf("failed to build resolver: %v", err)
- }
- // Start the resolver wrapper goroutine after resolverWrapper is created.
- //
- // If the goroutine is started before resolverWrapper is ready, the
- // following may happen: The goroutine sends updates to cc. cc forwards
- // those to balancer. Balancer creates new addrConn. addrConn fails to
- // connect, and calls resolveNow(). resolveNow() tries to use the non-ready
- // resolverWrapper.
- cc.resolverWrapper.start()
-
- // A blocking dial blocks until the clientConn is ready.
- if cc.dopts.block {
- for {
- s := cc.GetState()
- if s == connectivity.Ready {
- break
- }
- if !cc.WaitForStateChange(ctx, s) {
- // ctx got timeout or canceled.
- return nil, ctx.Err()
- }
- }
- }
-
- return cc, nil
-}
-
-// connectivityStateManager keeps the connectivity.State of ClientConn.
-// This struct will eventually be exported so the balancers can access it.
-type connectivityStateManager struct {
- mu sync.Mutex
- state connectivity.State
- notifyChan chan struct{}
-}
-
-// updateState updates the connectivity.State of ClientConn.
-// If there's a change it notifies goroutines waiting on state change to
-// happen.
-func (csm *connectivityStateManager) updateState(state connectivity.State) {
- csm.mu.Lock()
- defer csm.mu.Unlock()
- if csm.state == connectivity.Shutdown {
- return
- }
- if csm.state == state {
- return
- }
- csm.state = state
- if csm.notifyChan != nil {
- // There are other goroutines waiting on this channel.
- close(csm.notifyChan)
- csm.notifyChan = nil
- }
-}
-
-func (csm *connectivityStateManager) getState() connectivity.State {
- csm.mu.Lock()
- defer csm.mu.Unlock()
- return csm.state
-}
-
-func (csm *connectivityStateManager) getNotifyChan() <-chan struct{} {
- csm.mu.Lock()
- defer csm.mu.Unlock()
- if csm.notifyChan == nil {
- csm.notifyChan = make(chan struct{})
- }
- return csm.notifyChan
-}
-
-// ClientConn represents a client connection to an RPC server.
-type ClientConn struct {
- ctx context.Context
- cancel context.CancelFunc
-
- target string
- parsedTarget resolver.Target
- authority string
- dopts dialOptions
- csMgr *connectivityStateManager
-
- balancerBuildOpts balancer.BuildOptions
- resolverWrapper *ccResolverWrapper
- blockingpicker *pickerWrapper
-
- mu sync.RWMutex
- sc ServiceConfig
- scRaw string
- conns map[*addrConn]struct{}
- // Keepalive parameter can be updated if a GoAway is received.
- mkp keepalive.ClientParameters
- curBalancerName string
- preBalancerName string // previous balancer name.
- curAddresses []resolver.Address
- balancerWrapper *ccBalancerWrapper
-
- channelzID int64 // channelz unique identification number
- czmu sync.RWMutex
- callsStarted int64
- callsSucceeded int64
- callsFailed int64
- lastCallStartedTime time.Time
-}
-
-// 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.
-// This is an EXPERIMENTAL API.
-func (cc *ClientConn) WaitForStateChange(ctx context.Context, sourceState connectivity.State) bool {
- ch := cc.csMgr.getNotifyChan()
- if cc.csMgr.getState() != sourceState {
- return true
- }
- select {
- case <-ctx.Done():
- return false
- case <-ch:
- return true
- }
-}
-
-// GetState returns the connectivity.State of ClientConn.
-// This is an EXPERIMENTAL API.
-func (cc *ClientConn) GetState() connectivity.State {
- return cc.csMgr.getState()
-}
-
-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 revist this decision in the future.
- cc.sc = sc
- cc.scRaw = ""
- cc.mu.Unlock()
- case <-cc.ctx.Done():
- return
- }
- }
-}
-
-func (cc *ClientConn) handleResolvedAddrs(addrs []resolver.Address, err error) {
- cc.mu.Lock()
- defer cc.mu.Unlock()
- if cc.conns == nil {
- // cc was closed.
- return
- }
-
- if reflect.DeepEqual(cc.curAddresses, addrs) {
- return
- }
-
- cc.curAddresses = addrs
-
- if cc.dopts.balancerBuilder == nil {
- // Only look at balancer types and switch balancer if balancer dial
- // option is not set.
- var isGRPCLB bool
- for _, a := range addrs {
- if a.Type == resolver.GRPCLB {
- isGRPCLB = true
- break
- }
- }
- var newBalancerName string
- if isGRPCLB {
- newBalancerName = grpclbName
- } else {
- // Address list doesn't contain grpclb address. Try to pick a
- // non-grpclb balancer.
- newBalancerName = cc.curBalancerName
- // If current balancer is grpclb, switch to the previous one.
- if newBalancerName == grpclbName {
- newBalancerName = cc.preBalancerName
- }
- // The following could be true in two cases:
- // - the first time handling resolved addresses
- // (curBalancerName="")
- // - the first time handling non-grpclb addresses
- // (curBalancerName="grpclb", preBalancerName="")
- if newBalancerName == "" {
- newBalancerName = PickFirstBalancerName
- }
- }
- cc.switchBalancer(newBalancerName)
- } else if cc.balancerWrapper == nil {
- // Balancer dial option was set, and this is the first time handling
- // resolved addresses. Build a balancer with dopts.balancerBuilder.
- cc.balancerWrapper = newCCBalancerWrapper(cc, cc.dopts.balancerBuilder, cc.balancerBuildOpts)
- }
-
- cc.balancerWrapper.handleResolvedAddrs(addrs, nil)
-}
-
-// switchBalancer starts the switching from current balancer to the balancer
-// with the given name.
-//
-// It will NOT send the current address list to the new balancer. If needed,
-// caller of this function should send address list to the new balancer after
-// this function returns.
-//
-// Caller must hold cc.mu.
-func (cc *ClientConn) switchBalancer(name string) {
- if cc.conns == nil {
- return
- }
-
- if strings.ToLower(cc.curBalancerName) == strings.ToLower(name) {
- return
- }
-
- grpclog.Infof("ClientConn switching balancer to %q", name)
- if cc.dopts.balancerBuilder != nil {
- grpclog.Infoln("ignoring balancer switching: Balancer DialOption used instead")
- return
- }
- // TODO(bar switching) change this to two steps: drain and close.
- // Keep track of sc in wrapper.
- if cc.balancerWrapper != nil {
- cc.balancerWrapper.close()
- }
- // Clear all stickiness state.
- cc.blockingpicker.clearStickinessState()
-
- builder := balancer.Get(name)
- if builder == nil {
- grpclog.Infof("failed to get balancer builder for: %v, using pick_first instead", name)
- builder = newPickfirstBuilder()
- }
- cc.preBalancerName = cc.curBalancerName
- cc.curBalancerName = builder.Name()
- cc.balancerWrapper = newCCBalancerWrapper(cc, builder, cc.balancerBuildOpts)
-}
-
-func (cc *ClientConn) handleSubConnStateChange(sc balancer.SubConn, s connectivity.State) {
- cc.mu.Lock()
- if cc.conns == nil {
- cc.mu.Unlock()
- return
- }
- // TODO(bar switching) send updates to all balancer wrappers when balancer
- // gracefully switching is supported.
- cc.balancerWrapper.handleSubConnStateChange(sc, s)
- cc.mu.Unlock()
-}
-
-// newAddrConn 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) (*addrConn, error) {
- ac := &addrConn{
- cc: cc,
- addrs: addrs,
- dopts: cc.dopts,
- }
- 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()
- if cc.conns == nil {
- cc.mu.Unlock()
- return nil, ErrClientConnClosing
- }
- if channelz.IsOn() {
- ac.channelzID = channelz.RegisterSubChannel(ac, cc.channelzID, "")
- }
- cc.conns[ac] = struct{}{}
- cc.mu.Unlock()
- return ac, nil
-}
-
-// removeAddrConn removes the addrConn in the subConn from clientConn.
-// It also tears down the ac with the given error.
-func (cc *ClientConn) removeAddrConn(ac *addrConn, err error) {
- cc.mu.Lock()
- if cc.conns == nil {
- cc.mu.Unlock()
- return
- }
- delete(cc.conns, ac)
- cc.mu.Unlock()
- ac.tearDown(err)
-}
-
-// ChannelzMetric returns ChannelInternalMetric of current ClientConn.
-// This is an EXPERIMENTAL API.
-func (cc *ClientConn) ChannelzMetric() *channelz.ChannelInternalMetric {
- state := cc.GetState()
- cc.czmu.RLock()
- defer cc.czmu.RUnlock()
- return &channelz.ChannelInternalMetric{
- State: state,
- Target: cc.target,
- CallsStarted: cc.callsStarted,
- CallsSucceeded: cc.callsSucceeded,
- CallsFailed: cc.callsFailed,
- LastCallStartedTimestamp: cc.lastCallStartedTime,
- }
-}
-
-func (cc *ClientConn) incrCallsStarted() {
- cc.czmu.Lock()
- cc.callsStarted++
- // TODO(yuxuanli): will make this a time.Time pointer improve performance?
- cc.lastCallStartedTime = time.Now()
- cc.czmu.Unlock()
-}
-
-func (cc *ClientConn) incrCallsSucceeded() {
- cc.czmu.Lock()
- cc.callsSucceeded++
- cc.czmu.Unlock()
-}
-
-func (cc *ClientConn) incrCallsFailed() {
- cc.czmu.Lock()
- cc.callsFailed++
- cc.czmu.Unlock()
-}
-
-// connect starts to creating transport and also starts the transport monitor
-// goroutine for this ac.
-// It does nothing if the ac is not IDLE.
-// TODO(bar) Move this to the addrConn section.
-// This was part of resetAddrConn, keep it here to make the diff look clean.
-func (ac *addrConn) connect() error {
- ac.mu.Lock()
- if ac.state == connectivity.Shutdown {
- ac.mu.Unlock()
- return errConnClosing
- }
- if ac.state != connectivity.Idle {
- ac.mu.Unlock()
- return nil
- }
- ac.state = connectivity.Connecting
- ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
- ac.mu.Unlock()
-
- // Start a goroutine connecting to the server asynchronously.
- go func() {
- if err := ac.resetTransport(); err != nil {
- grpclog.Warningf("Failed to dial %s: %v; please retry.", ac.addrs[0].Addr, err)
- if err != errConnClosing {
- // Keep this ac in cc.conns, to get the reason it's torn down.
- ac.tearDown(err)
- }
- return
- }
- ac.transportMonitor()
- }()
- return nil
-}
-
-// tryUpdateAddrs tries to update ac.addrs with the new addresses list.
-//
-// It checks whether current connected address of ac is in the new addrs list.
-// - If true, it updates ac.addrs and returns true. The ac will keep using
-// the existing connection.
-// - If false, it does nothing and returns false.
-func (ac *addrConn) tryUpdateAddrs(addrs []resolver.Address) bool {
- ac.mu.Lock()
- defer ac.mu.Unlock()
- grpclog.Infof("addrConn: tryUpdateAddrs curAddr: %v, addrs: %v", ac.curAddr, addrs)
- if ac.state == connectivity.Shutdown {
- ac.addrs = addrs
- return true
- }
-
- var curAddrFound bool
- for _, a := range addrs {
- if reflect.DeepEqual(ac.curAddr, a) {
- curAddrFound = true
- break
- }
- }
- grpclog.Infof("addrConn: tryUpdateAddrs curAddrFound: %v", curAddrFound)
- if curAddrFound {
- ac.addrs = addrs
- ac.reconnectIdx = 0 // Start reconnecting from beginning in the new list.
- }
-
- return curAddrFound
-}
-
-// GetMethodConfig gets the method config of the input method.
-// If there's an exact match for input method (i.e. /service/method), we return
-// the corresponding MethodConfig.
-// If there isn't an exact match for the input method, we look for the default config
-// under the service (i.e /service/). If there is a default MethodConfig for
-// the service, we return it.
-// Otherwise, we return an empty MethodConfig.
-func (cc *ClientConn) GetMethodConfig(method string) MethodConfig {
- // TODO: Avoid the locking here.
- cc.mu.RLock()
- defer cc.mu.RUnlock()
- m, ok := cc.sc.Methods[method]
- if !ok {
- i := strings.LastIndex(method, "/")
- m = cc.sc.Methods[method[:i+1]]
- }
- return m
-}
-
-func (cc *ClientConn) getTransport(ctx context.Context, failfast bool) (transport.ClientTransport, func(balancer.DoneInfo), error) {
- t, done, err := cc.blockingpicker.pick(ctx, failfast, balancer.PickOptions{})
- if err != nil {
- return nil, nil, toRPCErr(err)
- }
- return t, done, nil
-}
-
-// handleServiceConfig parses the service config string in JSON format to Go native
-// struct ServiceConfig, and store both the struct and the JSON string in ClientConn.
-func (cc *ClientConn) handleServiceConfig(js string) error {
- if cc.dopts.disableServiceConfig {
- return nil
- }
- sc, err := parseServiceConfig(js)
- if err != nil {
- return err
- }
- cc.mu.Lock()
- cc.scRaw = js
- cc.sc = sc
- if sc.LB != nil && *sc.LB != grpclbName { // "grpclb" is not a valid balancer option in service config.
- if cc.curBalancerName == grpclbName {
- // If current balancer is grpclb, there's at least one grpclb
- // balancer address in the resolved list. Don't switch the balancer,
- // but change the previous balancer name, so if a new resolved
- // address list doesn't contain grpclb address, balancer will be
- // switched to *sc.LB.
- cc.preBalancerName = *sc.LB
- } else {
- cc.switchBalancer(*sc.LB)
- cc.balancerWrapper.handleResolvedAddrs(cc.curAddresses, nil)
- }
- }
-
- if envConfigStickinessOn {
- var newStickinessMDKey string
- if sc.stickinessMetadataKey != nil && *sc.stickinessMetadataKey != "" {
- newStickinessMDKey = *sc.stickinessMetadataKey
- }
- // newStickinessMDKey is "" if one of the following happens:
- // - stickinessMetadataKey is set to ""
- // - stickinessMetadataKey field doesn't exist in service config
- cc.blockingpicker.updateStickinessMDKey(strings.ToLower(newStickinessMDKey))
- }
-
- cc.mu.Unlock()
- return nil
-}
-
-func (cc *ClientConn) resolveNow(o resolver.ResolveNowOption) {
- cc.mu.RLock()
- r := cc.resolverWrapper
- cc.mu.RUnlock()
- if r == nil {
- return
- }
- go r.resolveNow(o)
-}
-
-// Close tears down the ClientConn and all underlying connections.
-func (cc *ClientConn) Close() error {
- defer cc.cancel()
-
- cc.mu.Lock()
- if cc.conns == nil {
- cc.mu.Unlock()
- return ErrClientConnClosing
- }
- conns := cc.conns
- cc.conns = nil
- cc.csMgr.updateState(connectivity.Shutdown)
-
- rWrapper := cc.resolverWrapper
- cc.resolverWrapper = nil
- bWrapper := cc.balancerWrapper
- cc.balancerWrapper = nil
- cc.mu.Unlock()
-
- cc.blockingpicker.close()
-
- if rWrapper != nil {
- rWrapper.close()
- }
- if bWrapper != nil {
- bWrapper.close()
- }
-
- for ac := range conns {
- ac.tearDown(ErrClientConnClosing)
- }
- if channelz.IsOn() {
- channelz.RemoveEntry(cc.channelzID)
- }
- return nil
-}
-
-// addrConn is a network connection to a given address.
-type addrConn struct {
- ctx context.Context
- cancel context.CancelFunc
-
- cc *ClientConn
- addrs []resolver.Address
- dopts dialOptions
- events trace.EventLog
- acbw balancer.SubConn
-
- mu sync.Mutex
- curAddr resolver.Address
- reconnectIdx int // The index in addrs list to start reconnecting from.
- state connectivity.State
- // ready is closed and becomes nil when a new transport is up or failed
- // due to timeout.
- ready chan struct{}
- transport transport.ClientTransport
-
- // The reason this addrConn is torn down.
- tearDownErr error
-
- connectRetryNum int
- // backoffDeadline is the time until which resetTransport needs to
- // wait before increasing connectRetryNum count.
- backoffDeadline time.Time
- // connectDeadline is the time by which all connection
- // negotiations must complete.
- connectDeadline time.Time
-
- channelzID int64 // channelz unique identification number
- czmu sync.RWMutex
- callsStarted int64
- callsSucceeded int64
- callsFailed int64
- lastCallStartedTime time.Time
-}
-
-// adjustParams updates parameters used to create transports upon
-// receiving a GoAway.
-func (ac *addrConn) adjustParams(r transport.GoAwayReason) {
- switch r {
- case transport.GoAwayTooManyPings:
- v := 2 * ac.dopts.copts.KeepaliveParams.Time
- ac.cc.mu.Lock()
- if v > ac.cc.mkp.Time {
- ac.cc.mkp.Time = v
- }
- ac.cc.mu.Unlock()
- }
-}
-
-// printf records an event in ac's event log, unless ac has been closed.
-// REQUIRES ac.mu is held.
-func (ac *addrConn) printf(format string, a ...interface{}) {
- if ac.events != nil {
- ac.events.Printf(format, a...)
- }
-}
-
-// errorf records an error in ac's event log, unless ac has been closed.
-// REQUIRES ac.mu is held.
-func (ac *addrConn) errorf(format string, a ...interface{}) {
- if ac.events != nil {
- ac.events.Errorf(format, a...)
- }
-}
-
-// resetTransport recreates a transport to the address for ac. The old
-// transport will close itself on error or when the clientconn is closed.
-// The created transport must receive initial settings frame from the server.
-// In case that doesn't happen, transportMonitor will kill the newly created
-// transport after connectDeadline has expired.
-// In case there was an error on the transport before the settings frame was
-// received, resetTransport resumes connecting to backends after the one that
-// was previously connected to. In case end of the list is reached, resetTransport
-// backs off until the original deadline.
-// If the DialOption WithWaitForHandshake was set, resetTrasport returns
-// successfully only after server settings are received.
-//
-// TODO(bar) make sure all state transitions are valid.
-func (ac *addrConn) resetTransport() error {
- ac.mu.Lock()
- if ac.state == connectivity.Shutdown {
- ac.mu.Unlock()
- return errConnClosing
- }
- if ac.ready != nil {
- close(ac.ready)
- ac.ready = nil
- }
- ac.transport = nil
- ridx := ac.reconnectIdx
- ac.mu.Unlock()
- ac.cc.mu.RLock()
- ac.dopts.copts.KeepaliveParams = ac.cc.mkp
- ac.cc.mu.RUnlock()
- var backoffDeadline, connectDeadline time.Time
- for connectRetryNum := 0; ; connectRetryNum++ {
- ac.mu.Lock()
- if ac.backoffDeadline.IsZero() {
- // This means either a successful HTTP2 connection was established
- // or this is the first time this addrConn is trying to establish a
- // connection.
- backoffFor := ac.dopts.bs.Backoff(connectRetryNum) // time.Duration.
- // This will be the duration that dial gets to finish.
- dialDuration := getMinConnectTimeout()
- if backoffFor > dialDuration {
- // Give dial more time as we keep failing to connect.
- dialDuration = backoffFor
- }
- start := time.Now()
- backoffDeadline = start.Add(backoffFor)
- connectDeadline = start.Add(dialDuration)
- ridx = 0 // Start connecting from the beginning.
- } else {
- // Continue trying to connect with the same deadlines.
- connectRetryNum = ac.connectRetryNum
- backoffDeadline = ac.backoffDeadline
- connectDeadline = ac.connectDeadline
- ac.backoffDeadline = time.Time{}
- ac.connectDeadline = time.Time{}
- ac.connectRetryNum = 0
- }
- if ac.state == connectivity.Shutdown {
- ac.mu.Unlock()
- return errConnClosing
- }
- ac.printf("connecting")
- if ac.state != connectivity.Connecting {
- ac.state = connectivity.Connecting
- ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
- }
- // copy ac.addrs in case of race
- addrsIter := make([]resolver.Address, len(ac.addrs))
- copy(addrsIter, ac.addrs)
- copts := ac.dopts.copts
- ac.mu.Unlock()
- connected, err := ac.createTransport(connectRetryNum, ridx, backoffDeadline, connectDeadline, addrsIter, copts)
- if err != nil {
- return err
- }
- if connected {
- return nil
- }
- }
-}
-
-// createTransport creates a connection to one of the backends in addrs.
-// It returns true if a connection was established.
-func (ac *addrConn) createTransport(connectRetryNum, ridx int, backoffDeadline, connectDeadline time.Time, addrs []resolver.Address, copts transport.ConnectOptions) (bool, error) {
- for i := ridx; i < len(addrs); i++ {
- addr := addrs[i]
- target := transport.TargetInfo{
- Addr: addr.Addr,
- Metadata: addr.Metadata,
- Authority: ac.cc.authority,
- }
- done := make(chan struct{})
- onPrefaceReceipt := func() {
- ac.mu.Lock()
- close(done)
- if !ac.backoffDeadline.IsZero() {
- // If we haven't already started reconnecting to
- // other backends.
- // Note, this can happen when writer notices an error
- // and triggers resetTransport while at the same time
- // reader receives the preface and invokes this closure.
- ac.backoffDeadline = time.Time{}
- ac.connectDeadline = time.Time{}
- ac.connectRetryNum = 0
- }
- ac.mu.Unlock()
- }
- // Do not cancel in the success path because of
- // this issue in Go1.6: https://github.com/golang/go/issues/15078.
- connectCtx, cancel := context.WithDeadline(ac.ctx, connectDeadline)
- if channelz.IsOn() {
- copts.ChannelzParentID = ac.channelzID
- }
- newTr, err := transport.NewClientTransport(connectCtx, ac.cc.ctx, target, copts, onPrefaceReceipt)
- if err != nil {
- cancel()
- ac.cc.blockingpicker.updateConnectionError(err)
- ac.mu.Lock()
- if ac.state == connectivity.Shutdown {
- // ac.tearDown(...) has been invoked.
- ac.mu.Unlock()
- return false, errConnClosing
- }
- ac.mu.Unlock()
- grpclog.Warningf("grpc: addrConn.createTransport failed to connect to %v. Err :%v. Reconnecting...", addr, err)
- continue
- }
- if ac.dopts.waitForHandshake {
- select {
- case <-done:
- case <-connectCtx.Done():
- // Didn't receive server preface, must kill this new transport now.
- grpclog.Warningf("grpc: addrConn.createTransport failed to receive server preface before deadline.")
- newTr.Close()
- break
- case <-ac.ctx.Done():
- }
- }
- ac.mu.Lock()
- if ac.state == connectivity.Shutdown {
- ac.mu.Unlock()
- // ac.tearDonn(...) has been invoked.
- newTr.Close()
- return false, errConnClosing
- }
- ac.printf("ready")
- ac.state = connectivity.Ready
- ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
- ac.transport = newTr
- ac.curAddr = addr
- if ac.ready != nil {
- close(ac.ready)
- ac.ready = nil
- }
- select {
- case <-done:
- // If the server has responded back with preface already,
- // don't set the reconnect parameters.
- default:
- ac.connectRetryNum = connectRetryNum
- ac.backoffDeadline = backoffDeadline
- ac.connectDeadline = connectDeadline
- ac.reconnectIdx = i + 1 // Start reconnecting from the next backend in the list.
- }
- ac.mu.Unlock()
- return true, nil
- }
- ac.mu.Lock()
- if ac.state == connectivity.Shutdown {
- ac.mu.Unlock()
- return false, errConnClosing
- }
- ac.state = connectivity.TransientFailure
- ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
- ac.cc.resolveNow(resolver.ResolveNowOption{})
- if ac.ready != nil {
- close(ac.ready)
- ac.ready = nil
- }
- ac.mu.Unlock()
- timer := time.NewTimer(backoffDeadline.Sub(time.Now()))
- select {
- case <-timer.C:
- case <-ac.ctx.Done():
- timer.Stop()
- return false, ac.ctx.Err()
- }
- return false, nil
-}
-
-// Run in a goroutine to track the error in transport and create the
-// new transport if an error happens. It returns when the channel is closing.
-func (ac *addrConn) transportMonitor() {
- for {
- var timer *time.Timer
- var cdeadline <-chan time.Time
- ac.mu.Lock()
- t := ac.transport
- if !ac.connectDeadline.IsZero() {
- timer = time.NewTimer(ac.connectDeadline.Sub(time.Now()))
- cdeadline = timer.C
- }
- ac.mu.Unlock()
- // Block until we receive a goaway or an error occurs.
- select {
- case <-t.GoAway():
- done := t.Error()
- cleanup := t.Close
- // Since this transport will be orphaned (won't have a transportMonitor)
- // we need to launch a goroutine to keep track of clientConn.Close()
- // happening since it might not be noticed by any other goroutine for a while.
- go func() {
- <-done
- cleanup()
- }()
- case <-t.Error():
- // In case this is triggered because clientConn.Close()
- // was called, we want to immeditately close the transport
- // since no other goroutine might notice it for a while.
- t.Close()
- case <-cdeadline:
- ac.mu.Lock()
- // This implies that client received server preface.
- if ac.backoffDeadline.IsZero() {
- ac.mu.Unlock()
- continue
- }
- ac.mu.Unlock()
- timer = nil
- // No server preface received until deadline.
- // Kill the connection.
- grpclog.Warningf("grpc: addrConn.transportMonitor didn't get server preface after waiting. Closing the new transport now.")
- t.Close()
- }
- if timer != nil {
- timer.Stop()
- }
- // If a GoAway happened, regardless of error, adjust our keepalive
- // parameters as appropriate.
- select {
- case <-t.GoAway():
- ac.adjustParams(t.GetGoAwayReason())
- default:
- }
- ac.mu.Lock()
- if ac.state == connectivity.Shutdown {
- ac.mu.Unlock()
- return
- }
- // Set connectivity state to TransientFailure before calling
- // resetTransport. Transition READY->CONNECTING is not valid.
- ac.state = connectivity.TransientFailure
- ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
- ac.cc.resolveNow(resolver.ResolveNowOption{})
- ac.curAddr = resolver.Address{}
- ac.mu.Unlock()
- if err := ac.resetTransport(); err != nil {
- ac.mu.Lock()
- ac.printf("transport exiting: %v", err)
- ac.mu.Unlock()
- grpclog.Warningf("grpc: addrConn.transportMonitor exits due to: %v", err)
- if err != errConnClosing {
- // Keep this ac in cc.conns, to get the reason it's torn down.
- ac.tearDown(err)
- }
- return
- }
- }
-}
-
-// wait blocks until i) the new transport is up or ii) ctx is done or iii) ac is closed or
-// iv) transport is in connectivity.TransientFailure and there is a balancer/failfast is true.
-func (ac *addrConn) wait(ctx context.Context, hasBalancer, failfast bool) (transport.ClientTransport, error) {
- for {
- ac.mu.Lock()
- switch {
- case ac.state == connectivity.Shutdown:
- if failfast || !hasBalancer {
- // RPC is failfast or balancer is nil. This RPC should fail with ac.tearDownErr.
- err := ac.tearDownErr
- ac.mu.Unlock()
- return nil, err
- }
- ac.mu.Unlock()
- return nil, errConnClosing
- case ac.state == connectivity.Ready:
- ct := ac.transport
- ac.mu.Unlock()
- return ct, nil
- case ac.state == connectivity.TransientFailure:
- if failfast || hasBalancer {
- ac.mu.Unlock()
- return nil, errConnUnavailable
- }
- }
- ready := ac.ready
- if ready == nil {
- ready = make(chan struct{})
- ac.ready = ready
- }
- ac.mu.Unlock()
- select {
- case <-ctx.Done():
- return nil, toRPCErr(ctx.Err())
- // Wait until the new transport is ready or failed.
- case <-ready:
- }
- }
-}
-
-// getReadyTransport returns the transport if ac's state is READY.
-// Otherwise it returns nil, false.
-// If ac's state is IDLE, it will trigger ac to connect.
-func (ac *addrConn) getReadyTransport() (transport.ClientTransport, bool) {
- ac.mu.Lock()
- if ac.state == connectivity.Ready {
- t := ac.transport
- ac.mu.Unlock()
- return t, true
- }
- var idle bool
- if ac.state == connectivity.Idle {
- idle = true
- }
- ac.mu.Unlock()
- // Trigger idle ac to connect.
- if idle {
- ac.connect()
- }
- return nil, false
-}
-
-// tearDown starts to tear down the addrConn.
-// TODO(zhaoq): Make this synchronous to avoid unbounded memory consumption in
-// some edge cases (e.g., the caller opens and closes many addrConn's in a
-// tight loop.
-// tearDown doesn't remove ac from ac.cc.conns.
-func (ac *addrConn) tearDown(err error) {
- ac.cancel()
- ac.mu.Lock()
- defer ac.mu.Unlock()
- if ac.state == connectivity.Shutdown {
- return
- }
- ac.curAddr = resolver.Address{}
- if err == errConnDrain && ac.transport != nil {
- // GracefulClose(...) may be executed multiple times when
- // i) receiving multiple GoAway frames from the server; or
- // ii) there are concurrent name resolver/Balancer triggered
- // address removal and GoAway.
- ac.transport.GracefulClose()
- }
- ac.state = connectivity.Shutdown
- ac.tearDownErr = err
- ac.cc.handleSubConnStateChange(ac.acbw, ac.state)
- if ac.events != nil {
- ac.events.Finish()
- ac.events = nil
- }
- if ac.ready != nil {
- close(ac.ready)
- ac.ready = nil
- }
- if channelz.IsOn() {
- channelz.RemoveEntry(ac.channelzID)
- }
-}
-
-func (ac *addrConn) getState() connectivity.State {
- ac.mu.Lock()
- defer ac.mu.Unlock()
- return ac.state
-}
-
-func (ac *addrConn) getCurAddr() (ret resolver.Address) {
- ac.mu.Lock()
- ret = ac.curAddr
- ac.mu.Unlock()
- return
-}
-
-func (ac *addrConn) ChannelzMetric() *channelz.ChannelInternalMetric {
- ac.mu.Lock()
- addr := ac.curAddr.Addr
- ac.mu.Unlock()
- state := ac.getState()
- ac.czmu.RLock()
- defer ac.czmu.RUnlock()
- return &channelz.ChannelInternalMetric{
- State: state,
- Target: addr,
- CallsStarted: ac.callsStarted,
- CallsSucceeded: ac.callsSucceeded,
- CallsFailed: ac.callsFailed,
- LastCallStartedTimestamp: ac.lastCallStartedTime,
- }
-}
-
-func (ac *addrConn) incrCallsStarted() {
- ac.czmu.Lock()
- ac.callsStarted++
- ac.lastCallStartedTime = time.Now()
- ac.czmu.Unlock()
-}
-
-func (ac *addrConn) incrCallsSucceeded() {
- ac.czmu.Lock()
- ac.callsSucceeded++
- ac.czmu.Unlock()
-}
-
-func (ac *addrConn) incrCallsFailed() {
- ac.czmu.Lock()
- ac.callsFailed++
- ac.czmu.Unlock()
-}
-
-// ErrClientConnTimeout indicates that the ClientConn cannot establish the
-// underlying connections within the specified timeout.
-//
-// Deprecated: This error is never returned by grpc and should not be
-// referenced by users.
-var ErrClientConnTimeout = errors.New("grpc: timed out when dialing")