From 1e5c432e1029601a664454388ae366ef69618d62 Mon Sep 17 00:00:00 2001 From: Christopher Speller Date: Mon, 25 Jun 2018 12:33:13 -0700 Subject: MM-10702 Moving plugins to use hashicorp go-plugin. (#8978) * Moving plugins to use hashicorp go-plugin. * Tweaks from feedback. --- .../grpc/grpclb_remote_balancer.go | 266 +++++++++++++++++++++ 1 file changed, 266 insertions(+) create mode 100644 vendor/google.golang.org/grpc/grpclb_remote_balancer.go (limited to 'vendor/google.golang.org/grpc/grpclb_remote_balancer.go') diff --git a/vendor/google.golang.org/grpc/grpclb_remote_balancer.go b/vendor/google.golang.org/grpc/grpclb_remote_balancer.go new file mode 100644 index 000000000..b8dd4f18c --- /dev/null +++ b/vendor/google.golang.org/grpc/grpclb_remote_balancer.go @@ -0,0 +1,266 @@ +/* + * + * 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" + "net" + "reflect" + "time" + + "golang.org/x/net/context" + "google.golang.org/grpc/balancer" + "google.golang.org/grpc/channelz" + + "google.golang.org/grpc/connectivity" + lbpb "google.golang.org/grpc/grpclb/grpc_lb_v1/messages" + "google.golang.org/grpc/grpclog" + "google.golang.org/grpc/metadata" + "google.golang.org/grpc/resolver" +) + +// processServerList updates balaner's internal state, create/remove SubConns +// and regenerates picker using the received serverList. +func (lb *lbBalancer) processServerList(l *lbpb.ServerList) { + grpclog.Infof("lbBalancer: processing server list: %+v", l) + lb.mu.Lock() + defer lb.mu.Unlock() + + // Set serverListReceived to true so fallback will not take effect if it has + // not hit timeout. + lb.serverListReceived = true + + // If the new server list == old server list, do nothing. + if reflect.DeepEqual(lb.fullServerList, l.Servers) { + grpclog.Infof("lbBalancer: new serverlist same as the previous one, ignoring") + return + } + lb.fullServerList = l.Servers + + var backendAddrs []resolver.Address + for _, s := range l.Servers { + if s.DropForLoadBalancing || s.DropForRateLimiting { + continue + } + + md := metadata.Pairs(lbTokeyKey, s.LoadBalanceToken) + ip := net.IP(s.IpAddress) + ipStr := ip.String() + if ip.To4() == nil { + // Add square brackets to ipv6 addresses, otherwise net.Dial() and + // net.SplitHostPort() will return too many colons error. + ipStr = fmt.Sprintf("[%s]", ipStr) + } + addr := resolver.Address{ + Addr: fmt.Sprintf("%s:%d", ipStr, s.Port), + Metadata: &md, + } + + backendAddrs = append(backendAddrs, addr) + } + + // Call refreshSubConns to create/remove SubConns. + lb.refreshSubConns(backendAddrs) + // Regenerate and update picker no matter if there's update on backends (if + // any SubConn will be newed/removed). Because since the full serverList was + // different, there might be updates in drops or pick weights(different + // number of duplicates). We need to update picker with the fulllist. + // + // Now with cache, even if SubConn was newed/removed, there might be no + // state changes. + lb.regeneratePicker() + lb.cc.UpdateBalancerState(lb.state, lb.picker) +} + +// refreshSubConns creates/removes SubConns with backendAddrs. It returns a bool +// indicating whether the backendAddrs are different from the cached +// backendAddrs (whether any SubConn was newed/removed). +// Caller must hold lb.mu. +func (lb *lbBalancer) refreshSubConns(backendAddrs []resolver.Address) bool { + lb.backendAddrs = nil + var backendsUpdated bool + // addrsSet is the set converted from backendAddrs, it's used to quick + // lookup for an address. + addrsSet := make(map[resolver.Address]struct{}) + // Create new SubConns. + for _, addr := range backendAddrs { + addrWithoutMD := addr + addrWithoutMD.Metadata = nil + addrsSet[addrWithoutMD] = struct{}{} + lb.backendAddrs = append(lb.backendAddrs, addrWithoutMD) + + if _, ok := lb.subConns[addrWithoutMD]; !ok { + backendsUpdated = true + + // Use addrWithMD to create the SubConn. + sc, err := lb.cc.NewSubConn([]resolver.Address{addr}, balancer.NewSubConnOptions{}) + if err != nil { + grpclog.Warningf("roundrobinBalancer: failed to create new SubConn: %v", err) + continue + } + lb.subConns[addrWithoutMD] = sc // Use the addr without MD as key for the map. + if _, ok := lb.scStates[sc]; !ok { + // Only set state of new sc to IDLE. The state could already be + // READY for cached SubConns. + lb.scStates[sc] = connectivity.Idle + } + sc.Connect() + } + } + + for a, sc := range lb.subConns { + // a was removed by resolver. + if _, ok := addrsSet[a]; !ok { + backendsUpdated = true + + lb.cc.RemoveSubConn(sc) + delete(lb.subConns, a) + // Keep the state of this sc in b.scStates until sc's state becomes Shutdown. + // The entry will be deleted in HandleSubConnStateChange. + } + } + + return backendsUpdated +} + +func (lb *lbBalancer) readServerList(s *balanceLoadClientStream) error { + for { + reply, err := s.Recv() + if err != nil { + return fmt.Errorf("grpclb: failed to recv server list: %v", err) + } + if serverList := reply.GetServerList(); serverList != nil { + lb.processServerList(serverList) + } + } +} + +func (lb *lbBalancer) sendLoadReport(s *balanceLoadClientStream, interval time.Duration) { + ticker := time.NewTicker(interval) + defer ticker.Stop() + for { + select { + case <-ticker.C: + case <-s.Context().Done(): + return + } + stats := lb.clientStats.toClientStats() + t := time.Now() + stats.Timestamp = &lbpb.Timestamp{ + Seconds: t.Unix(), + Nanos: int32(t.Nanosecond()), + } + if err := s.Send(&lbpb.LoadBalanceRequest{ + LoadBalanceRequestType: &lbpb.LoadBalanceRequest_ClientStats{ + ClientStats: stats, + }, + }); err != nil { + return + } + } +} + +func (lb *lbBalancer) callRemoteBalancer() error { + lbClient := &loadBalancerClient{cc: lb.ccRemoteLB} + ctx, cancel := context.WithCancel(context.Background()) + defer cancel() + stream, err := lbClient.BalanceLoad(ctx, FailFast(false)) + if err != nil { + return fmt.Errorf("grpclb: failed to perform RPC to the remote balancer %v", err) + } + + // grpclb handshake on the stream. + initReq := &lbpb.LoadBalanceRequest{ + LoadBalanceRequestType: &lbpb.LoadBalanceRequest_InitialRequest{ + InitialRequest: &lbpb.InitialLoadBalanceRequest{ + Name: lb.target, + }, + }, + } + if err := stream.Send(initReq); err != nil { + return fmt.Errorf("grpclb: failed to send init request: %v", err) + } + reply, err := stream.Recv() + if err != nil { + return fmt.Errorf("grpclb: failed to recv init response: %v", err) + } + initResp := reply.GetInitialResponse() + if initResp == nil { + return fmt.Errorf("grpclb: reply from remote balancer did not include initial response") + } + if initResp.LoadBalancerDelegate != "" { + return fmt.Errorf("grpclb: Delegation is not supported") + } + + go func() { + if d := convertDuration(initResp.ClientStatsReportInterval); d > 0 { + lb.sendLoadReport(stream, d) + } + }() + return lb.readServerList(stream) +} + +func (lb *lbBalancer) watchRemoteBalancer() { + for { + err := lb.callRemoteBalancer() + select { + case <-lb.doneCh: + return + default: + if err != nil { + grpclog.Error(err) + } + } + + } +} + +func (lb *lbBalancer) dialRemoteLB(remoteLBName string) { + var dopts []DialOption + if creds := lb.opt.DialCreds; creds != nil { + if err := creds.OverrideServerName(remoteLBName); err == nil { + dopts = append(dopts, WithTransportCredentials(creds)) + } else { + grpclog.Warningf("grpclb: failed to override the server name in the credentials: %v, using Insecure", err) + dopts = append(dopts, WithInsecure()) + } + } else { + dopts = append(dopts, WithInsecure()) + } + if lb.opt.Dialer != nil { + // WithDialer takes a different type of function, so we instead use a + // special DialOption here. + dopts = append(dopts, withContextDialer(lb.opt.Dialer)) + } + // Explicitly set pickfirst as the balancer. + dopts = append(dopts, WithBalancerName(PickFirstBalancerName)) + dopts = append(dopts, withResolverBuilder(lb.manualResolver)) + if channelz.IsOn() { + dopts = append(dopts, WithChannelzParentID(lb.opt.ChannelzParentID)) + } + + // DialContext using manualResolver.Scheme, which is a random scheme generated + // when init grpclb. The target name is not important. + cc, err := DialContext(context.Background(), "grpclb:///grpclb.server", dopts...) + if err != nil { + grpclog.Fatalf("failed to dial: %v", err) + } + lb.ccRemoteLB = cc + go lb.watchRemoteBalancer() +} -- cgit v1.2.3-1-g7c22