diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/resolver_conn_wrapper.go')
-rw-r--r-- | vendor/google.golang.org/grpc/resolver_conn_wrapper.go | 155 |
1 files changed, 155 insertions, 0 deletions
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 000000000..9d7602539 --- /dev/null +++ b/vendor/google.golang.org/grpc/resolver_conn_wrapper.go @@ -0,0 +1,155 @@ +/* + * + * 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" + + "google.golang.org/grpc/grpclog" + "google.golang.org/grpc/internal/channelz" + "google.golang.org/grpc/resolver" +) + +// 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 chan struct{} + lastAddressesCount int +} + +// split2 returns the values from strings.SplitN(s, sep, 2). +// If sep is not found, it returns ("", s, 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 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. +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, + addrCh: make(chan []resolver.Address, 1), + scCh: make(chan string, 1), + done: make(chan struct{}), + } + + var err error + ccr.resolver, err = rb.Build(cc.parsedTarget, ccr, resolver.BuildOption{DisableServiceConfig: cc.dopts.disableServiceConfig}) + if err != nil { + return nil, err + } + return ccr, nil +} + +func (ccr *ccResolverWrapper) resolveNow(o resolver.ResolveNowOption) { + ccr.resolver.ResolveNow(o) +} + +func (ccr *ccResolverWrapper) close() { + ccr.resolver.Close() + close(ccr.done) +} + +// NewAddress is called by the resolver implemenetion to send addresses to gRPC. +func (ccr *ccResolverWrapper) NewAddress(addrs []resolver.Address) { + select { + case <-ccr.done: + return + default: + } + grpclog.Infof("ccResolverWrapper: sending new addresses to cc: %v", addrs) + if channelz.IsOn() { + ccr.addChannelzTraceEvent(addrs) + } + ccr.cc.handleResolvedAddrs(addrs, nil) +} + +// NewServiceConfig is called by the resolver implemenetion to send service +// configs to gRPC. +func (ccr *ccResolverWrapper) NewServiceConfig(sc string) { + select { + case <-ccr.done: + return + default: + } + grpclog.Infof("ccResolverWrapper: got new service config: %v", sc) + ccr.cc.handleServiceConfig(sc) +} + +func (ccr *ccResolverWrapper) addChannelzTraceEvent(addrs []resolver.Address) { + if len(addrs) == 0 && ccr.lastAddressesCount != 0 { + channelz.AddTraceEvent(ccr.cc.channelzID, &channelz.TraceEventDesc{ + Desc: "Resolver returns an empty address list", + Severity: channelz.CtWarning, + }) + } else if len(addrs) != 0 && ccr.lastAddressesCount == 0 { + var s string + for i, a := range addrs { + if a.ServerName != "" { + s += a.Addr + "(" + a.ServerName + ")" + } else { + s += a.Addr + } + if i != len(addrs)-1 { + s += " " + } + } + channelz.AddTraceEvent(ccr.cc.channelzID, &channelz.TraceEventDesc{ + Desc: fmt.Sprintf("Resolver returns a non-empty address list (previous one was empty) %q", s), + Severity: channelz.CtINFO, + }) + } + ccr.lastAddressesCount = len(addrs) +} |