gRPC migration update
Change-Id: Icdd1a824948fa994cd36bd121c962f5ecf74e3cf
diff --git a/vendor/google.golang.org/grpc/resolver_conn_wrapper.go b/vendor/google.golang.org/grpc/resolver_conn_wrapper.go
index 6934905..7dcefcf 100644
--- a/vendor/google.golang.org/grpc/resolver_conn_wrapper.go
+++ b/vendor/google.golang.org/grpc/resolver_conn_wrapper.go
@@ -21,22 +21,29 @@
import (
"fmt"
"strings"
- "sync/atomic"
+ "sync"
+ "time"
+ "google.golang.org/grpc/balancer"
+ "google.golang.org/grpc/credentials"
"google.golang.org/grpc/grpclog"
"google.golang.org/grpc/internal/channelz"
+ "google.golang.org/grpc/internal/grpcsync"
"google.golang.org/grpc/resolver"
+ "google.golang.org/grpc/serviceconfig"
)
// ccResolverWrapper is a wrapper on top of cc for resolvers.
// It implements resolver.ClientConnection interface.
type ccResolverWrapper struct {
- cc *ClientConn
- resolver resolver.Resolver
- addrCh chan []resolver.Address
- scCh chan string
- done uint32 // accessed atomically; set to 1 when closed.
- curState resolver.State
+ cc *ClientConn
+ resolverMu sync.Mutex
+ resolver resolver.Resolver
+ done *grpcsync.Event
+ curState resolver.State
+
+ pollingMu sync.Mutex
+ polling chan struct{}
}
// split2 returns the values from strings.SplitN(s, sep, 2).
@@ -67,12 +74,9 @@
return ret
}
-// newCCResolverWrapper parses cc.target for scheme and gets the resolver
-// builder for this scheme and builds the resolver. The monitoring goroutine
-// for it is not started yet and can be created by calling start().
-//
-// If withResolverBuilder dial option is set, the specified resolver will be
-// used instead.
+// newCCResolverWrapper uses the resolver.Builder stored in the ClientConn to
+// build a Resolver and returns a ccResolverWrapper object which wraps the
+// newly built resolver.
func newCCResolverWrapper(cc *ClientConn) (*ccResolverWrapper, error) {
rb := cc.dopts.resolverBuilder
if rb == nil {
@@ -80,47 +84,122 @@
}
ccr := &ccResolverWrapper{
- cc: cc,
- addrCh: make(chan []resolver.Address, 1),
- scCh: make(chan string, 1),
+ cc: cc,
+ done: grpcsync.NewEvent(),
+ }
+
+ var credsClone credentials.TransportCredentials
+ if creds := cc.dopts.copts.TransportCredentials; creds != nil {
+ credsClone = creds.Clone()
+ }
+ rbo := resolver.BuildOption{
+ DisableServiceConfig: cc.dopts.disableServiceConfig,
+ DialCreds: credsClone,
+ CredsBundle: cc.dopts.copts.CredsBundle,
+ Dialer: cc.dopts.copts.Dialer,
}
var err error
- ccr.resolver, err = rb.Build(cc.parsedTarget, ccr, resolver.BuildOption{DisableServiceConfig: cc.dopts.disableServiceConfig})
+ // We need to hold the lock here while we assign to the ccr.resolver field
+ // to guard against a data race caused by the following code path,
+ // rb.Build-->ccr.ReportError-->ccr.poll-->ccr.resolveNow, would end up
+ // accessing ccr.resolver which is being assigned here.
+ ccr.resolverMu.Lock()
+ ccr.resolver, err = rb.Build(cc.parsedTarget, ccr, rbo)
if err != nil {
return nil, err
}
+ ccr.resolverMu.Unlock()
return ccr, nil
}
func (ccr *ccResolverWrapper) resolveNow(o resolver.ResolveNowOption) {
- ccr.resolver.ResolveNow(o)
+ ccr.resolverMu.Lock()
+ if !ccr.done.HasFired() {
+ ccr.resolver.ResolveNow(o)
+ }
+ ccr.resolverMu.Unlock()
}
func (ccr *ccResolverWrapper) close() {
+ ccr.resolverMu.Lock()
ccr.resolver.Close()
- atomic.StoreUint32(&ccr.done, 1)
+ ccr.done.Fire()
+ ccr.resolverMu.Unlock()
}
-func (ccr *ccResolverWrapper) isDone() bool {
- return atomic.LoadUint32(&ccr.done) == 1
+// poll begins or ends asynchronous polling of the resolver based on whether
+// err is ErrBadResolverState.
+func (ccr *ccResolverWrapper) poll(err error) {
+ ccr.pollingMu.Lock()
+ defer ccr.pollingMu.Unlock()
+ if err != balancer.ErrBadResolverState {
+ // stop polling
+ if ccr.polling != nil {
+ close(ccr.polling)
+ ccr.polling = nil
+ }
+ return
+ }
+ if ccr.polling != nil {
+ // already polling
+ return
+ }
+ p := make(chan struct{})
+ ccr.polling = p
+ go func() {
+ for i := 0; ; i++ {
+ ccr.resolveNow(resolver.ResolveNowOption{})
+ t := time.NewTimer(ccr.cc.dopts.resolveNowBackoff(i))
+ select {
+ case <-p:
+ t.Stop()
+ return
+ case <-ccr.done.Done():
+ // Resolver has been closed.
+ t.Stop()
+ return
+ case <-t.C:
+ select {
+ case <-p:
+ return
+ default:
+ }
+ // Timer expired; re-resolve.
+ }
+ }
+ }()
}
func (ccr *ccResolverWrapper) UpdateState(s resolver.State) {
- if ccr.isDone() {
+ if ccr.done.HasFired() {
return
}
grpclog.Infof("ccResolverWrapper: sending update to cc: %v", s)
if channelz.IsOn() {
ccr.addChannelzTraceEvent(s)
}
- ccr.cc.updateResolverState(s)
ccr.curState = s
+ ccr.poll(ccr.cc.updateResolverState(ccr.curState, nil))
+}
+
+func (ccr *ccResolverWrapper) ReportError(err error) {
+ if ccr.done.HasFired() {
+ return
+ }
+ grpclog.Warningf("ccResolverWrapper: reporting error to cc: %v", err)
+ if channelz.IsOn() {
+ channelz.AddTraceEvent(ccr.cc.channelzID, &channelz.TraceEventDesc{
+ Desc: fmt.Sprintf("Resolver reported error: %v", err),
+ Severity: channelz.CtWarning,
+ })
+ }
+ ccr.poll(ccr.cc.updateResolverState(resolver.State{}, err))
}
// NewAddress is called by the resolver implementation to send addresses to gRPC.
func (ccr *ccResolverWrapper) NewAddress(addrs []resolver.Address) {
- if ccr.isDone() {
+ if ccr.done.HasFired() {
return
}
grpclog.Infof("ccResolverWrapper: sending new addresses to cc: %v", addrs)
@@ -128,31 +207,49 @@
ccr.addChannelzTraceEvent(resolver.State{Addresses: addrs, ServiceConfig: ccr.curState.ServiceConfig})
}
ccr.curState.Addresses = addrs
- ccr.cc.updateResolverState(ccr.curState)
+ ccr.poll(ccr.cc.updateResolverState(ccr.curState, nil))
}
// NewServiceConfig is called by the resolver implementation to send service
// configs to gRPC.
func (ccr *ccResolverWrapper) NewServiceConfig(sc string) {
- if ccr.isDone() {
+ if ccr.done.HasFired() {
return
}
grpclog.Infof("ccResolverWrapper: got new service config: %v", sc)
- c, err := parseServiceConfig(sc)
- if err != nil {
+ scpr := parseServiceConfig(sc)
+ if scpr.Err != nil {
+ grpclog.Warningf("ccResolverWrapper: error parsing service config: %v", scpr.Err)
+ if channelz.IsOn() {
+ channelz.AddTraceEvent(ccr.cc.channelzID, &channelz.TraceEventDesc{
+ Desc: fmt.Sprintf("Error parsing service config: %v", scpr.Err),
+ Severity: channelz.CtWarning,
+ })
+ }
+ ccr.poll(balancer.ErrBadResolverState)
return
}
if channelz.IsOn() {
- ccr.addChannelzTraceEvent(resolver.State{Addresses: ccr.curState.Addresses, ServiceConfig: c})
+ ccr.addChannelzTraceEvent(resolver.State{Addresses: ccr.curState.Addresses, ServiceConfig: scpr})
}
- ccr.curState.ServiceConfig = c
- ccr.cc.updateResolverState(ccr.curState)
+ ccr.curState.ServiceConfig = scpr
+ ccr.poll(ccr.cc.updateResolverState(ccr.curState, nil))
+}
+
+func (ccr *ccResolverWrapper) ParseServiceConfig(scJSON string) *serviceconfig.ParseResult {
+ return parseServiceConfig(scJSON)
}
func (ccr *ccResolverWrapper) addChannelzTraceEvent(s resolver.State) {
var updates []string
- oldSC, oldOK := ccr.curState.ServiceConfig.(*ServiceConfig)
- newSC, newOK := s.ServiceConfig.(*ServiceConfig)
+ var oldSC, newSC *ServiceConfig
+ var oldOK, newOK bool
+ if ccr.curState.ServiceConfig != nil {
+ oldSC, oldOK = ccr.curState.ServiceConfig.Config.(*ServiceConfig)
+ }
+ if s.ServiceConfig != nil {
+ newSC, newOK = s.ServiceConfig.Config.(*ServiceConfig)
+ }
if oldOK != newOK || (oldOK && newOK && oldSC.rawJSONString != newSC.rawJSONString) {
updates = append(updates, "service config updated")
}