First Commit of Voltha-Go-Controller from Radisys
Change-Id: I8e2e908e7ab09a4fe3d86849da18b6d69dcf4ab0
diff --git a/vendor/google.golang.org/grpc/resolver_conn_wrapper.go b/vendor/google.golang.org/grpc/resolver_conn_wrapper.go
new file mode 100644
index 0000000..7dcefcf
--- /dev/null
+++ b/vendor/google.golang.org/grpc/resolver_conn_wrapper.go
@@ -0,0 +1,265 @@
+/*
+ *
+ * Copyright 2017 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package grpc
+
+import (
+ "fmt"
+ "strings"
+ "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
+ 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).
+// If sep is not found, it returns ("", "", false) instead.
+func split2(s, sep string) (string, string, bool) {
+ spl := strings.SplitN(s, sep, 2)
+ if len(spl) < 2 {
+ return "", "", false
+ }
+ return spl[0], spl[1], true
+}
+
+// parseTarget splits target into a struct containing scheme, authority and
+// endpoint.
+//
+// If target is not a valid scheme://authority/endpoint, it returns {Endpoint:
+// target}.
+func parseTarget(target string) (ret resolver.Target) {
+ var ok bool
+ ret.Scheme, ret.Endpoint, ok = split2(target, "://")
+ if !ok {
+ return resolver.Target{Endpoint: target}
+ }
+ ret.Authority, ret.Endpoint, ok = split2(ret.Endpoint, "/")
+ if !ok {
+ return resolver.Target{Endpoint: target}
+ }
+ return ret
+}
+
+// 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 {
+ return nil, fmt.Errorf("could not get resolver for scheme: %q", cc.parsedTarget.Scheme)
+ }
+
+ ccr := &ccResolverWrapper{
+ 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
+ // 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.resolverMu.Lock()
+ if !ccr.done.HasFired() {
+ ccr.resolver.ResolveNow(o)
+ }
+ ccr.resolverMu.Unlock()
+}
+
+func (ccr *ccResolverWrapper) close() {
+ ccr.resolverMu.Lock()
+ ccr.resolver.Close()
+ ccr.done.Fire()
+ ccr.resolverMu.Unlock()
+}
+
+// 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.done.HasFired() {
+ return
+ }
+ grpclog.Infof("ccResolverWrapper: sending update to cc: %v", s)
+ if channelz.IsOn() {
+ ccr.addChannelzTraceEvent(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.done.HasFired() {
+ return
+ }
+ grpclog.Infof("ccResolverWrapper: sending new addresses to cc: %v", addrs)
+ if channelz.IsOn() {
+ ccr.addChannelzTraceEvent(resolver.State{Addresses: addrs, ServiceConfig: ccr.curState.ServiceConfig})
+ }
+ ccr.curState.Addresses = addrs
+ 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.done.HasFired() {
+ return
+ }
+ grpclog.Infof("ccResolverWrapper: got new service config: %v", sc)
+ 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: scpr})
+ }
+ 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
+ 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")
+ }
+ if len(ccr.curState.Addresses) > 0 && len(s.Addresses) == 0 {
+ updates = append(updates, "resolver returned an empty address list")
+ } else if len(ccr.curState.Addresses) == 0 && len(s.Addresses) > 0 {
+ updates = append(updates, "resolver returned new addresses")
+ }
+ channelz.AddTraceEvent(ccr.cc.channelzID, &channelz.TraceEventDesc{
+ Desc: fmt.Sprintf("Resolver state updated: %+v (%v)", s, strings.Join(updates, "; ")),
+ Severity: channelz.CtINFO,
+ })
+}