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Diffstat (limited to 'vendor/google.golang.org/grpc/grpclb.go')
| -rw-r--r-- | vendor/google.golang.org/grpc/grpclb.go | 341 |
1 files changed, 0 insertions, 341 deletions
diff --git a/vendor/google.golang.org/grpc/grpclb.go b/vendor/google.golang.org/grpc/grpclb.go deleted file mode 100644 index bc2b44525..000000000 --- a/vendor/google.golang.org/grpc/grpclb.go +++ /dev/null @@ -1,341 +0,0 @@ -/* - * - * Copyright 2016 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 ( - "strconv" - "strings" - "sync" - "time" - - "golang.org/x/net/context" - "google.golang.org/grpc/balancer" - "google.golang.org/grpc/connectivity" - lbpb "google.golang.org/grpc/grpclb/grpc_lb_v1/messages" - "google.golang.org/grpc/grpclog" - "google.golang.org/grpc/resolver" -) - -const ( - lbTokeyKey = "lb-token" - defaultFallbackTimeout = 10 * time.Second - grpclbName = "grpclb" -) - -func convertDuration(d *lbpb.Duration) time.Duration { - if d == nil { - return 0 - } - return time.Duration(d.Seconds)*time.Second + time.Duration(d.Nanos)*time.Nanosecond -} - -// Client API for LoadBalancer service. -// Mostly copied from generated pb.go file. -// To avoid circular dependency. -type loadBalancerClient struct { - cc *ClientConn -} - -func (c *loadBalancerClient) BalanceLoad(ctx context.Context, opts ...CallOption) (*balanceLoadClientStream, error) { - desc := &StreamDesc{ - StreamName: "BalanceLoad", - ServerStreams: true, - ClientStreams: true, - } - stream, err := c.cc.NewStream(ctx, desc, "/grpc.lb.v1.LoadBalancer/BalanceLoad", opts...) - if err != nil { - return nil, err - } - x := &balanceLoadClientStream{stream} - return x, nil -} - -type balanceLoadClientStream struct { - ClientStream -} - -func (x *balanceLoadClientStream) Send(m *lbpb.LoadBalanceRequest) error { - return x.ClientStream.SendMsg(m) -} - -func (x *balanceLoadClientStream) Recv() (*lbpb.LoadBalanceResponse, error) { - m := new(lbpb.LoadBalanceResponse) - if err := x.ClientStream.RecvMsg(m); err != nil { - return nil, err - } - return m, nil -} - -func init() { - balancer.Register(newLBBuilder()) -} - -// newLBBuilder creates a builder for grpclb. -func newLBBuilder() balancer.Builder { - return NewLBBuilderWithFallbackTimeout(defaultFallbackTimeout) -} - -// NewLBBuilderWithFallbackTimeout creates a grpclb builder with the given -// fallbackTimeout. If no response is received from the remote balancer within -// fallbackTimeout, the backend addresses from the resolved address list will be -// used. -// -// Only call this function when a non-default fallback timeout is needed. -func NewLBBuilderWithFallbackTimeout(fallbackTimeout time.Duration) balancer.Builder { - return &lbBuilder{ - fallbackTimeout: fallbackTimeout, - } -} - -type lbBuilder struct { - fallbackTimeout time.Duration -} - -func (b *lbBuilder) Name() string { - return grpclbName -} - -func (b *lbBuilder) Build(cc balancer.ClientConn, opt balancer.BuildOptions) balancer.Balancer { - // This generates a manual resolver builder with a random scheme. This - // scheme will be used to dial to remote LB, so we can send filtered address - // updates to remote LB ClientConn using this manual resolver. - scheme := "grpclb_internal_" + strconv.FormatInt(time.Now().UnixNano(), 36) - r := &lbManualResolver{scheme: scheme, ccb: cc} - - var target string - targetSplitted := strings.Split(cc.Target(), ":///") - if len(targetSplitted) < 2 { - target = cc.Target() - } else { - target = targetSplitted[1] - } - - lb := &lbBalancer{ - cc: newLBCacheClientConn(cc), - target: target, - opt: opt, - fallbackTimeout: b.fallbackTimeout, - doneCh: make(chan struct{}), - - manualResolver: r, - csEvltr: &connectivityStateEvaluator{}, - subConns: make(map[resolver.Address]balancer.SubConn), - scStates: make(map[balancer.SubConn]connectivity.State), - picker: &errPicker{err: balancer.ErrNoSubConnAvailable}, - clientStats: &rpcStats{}, - } - - return lb -} - -type lbBalancer struct { - cc *lbCacheClientConn - target string - opt balancer.BuildOptions - fallbackTimeout time.Duration - doneCh chan struct{} - - // manualResolver is used in the remote LB ClientConn inside grpclb. When - // resolved address updates are received by grpclb, filtered updates will be - // send to remote LB ClientConn through this resolver. - manualResolver *lbManualResolver - // The ClientConn to talk to the remote balancer. - ccRemoteLB *ClientConn - - // Support client side load reporting. Each picker gets a reference to this, - // and will update its content. - clientStats *rpcStats - - mu sync.Mutex // guards everything following. - // The full server list including drops, used to check if the newly received - // serverList contains anything new. Each generate picker will also have - // reference to this list to do the first layer pick. - fullServerList []*lbpb.Server - // All backends addresses, with metadata set to nil. This list contains all - // backend addresses in the same order and with the same duplicates as in - // serverlist. When generating picker, a SubConn slice with the same order - // but with only READY SCs will be gerenated. - backendAddrs []resolver.Address - // Roundrobin functionalities. - csEvltr *connectivityStateEvaluator - state connectivity.State - subConns map[resolver.Address]balancer.SubConn // Used to new/remove SubConn. - scStates map[balancer.SubConn]connectivity.State // Used to filter READY SubConns. - picker balancer.Picker - // Support fallback to resolved backend addresses if there's no response - // from remote balancer within fallbackTimeout. - fallbackTimerExpired bool - serverListReceived bool - // resolvedBackendAddrs is resolvedAddrs minus remote balancers. It's set - // when resolved address updates are received, and read in the goroutine - // handling fallback. - resolvedBackendAddrs []resolver.Address -} - -// regeneratePicker takes a snapshot of the balancer, and generates a picker from -// it. The picker -// - always returns ErrTransientFailure if the balancer is in TransientFailure, -// - does two layer roundrobin pick otherwise. -// Caller must hold lb.mu. -func (lb *lbBalancer) regeneratePicker() { - if lb.state == connectivity.TransientFailure { - lb.picker = &errPicker{err: balancer.ErrTransientFailure} - return - } - var readySCs []balancer.SubConn - for _, a := range lb.backendAddrs { - if sc, ok := lb.subConns[a]; ok { - if st, ok := lb.scStates[sc]; ok && st == connectivity.Ready { - readySCs = append(readySCs, sc) - } - } - } - - if len(lb.fullServerList) <= 0 { - if len(readySCs) <= 0 { - lb.picker = &errPicker{err: balancer.ErrNoSubConnAvailable} - return - } - lb.picker = &rrPicker{subConns: readySCs} - return - } - lb.picker = &lbPicker{ - serverList: lb.fullServerList, - subConns: readySCs, - stats: lb.clientStats, - } -} - -func (lb *lbBalancer) HandleSubConnStateChange(sc balancer.SubConn, s connectivity.State) { - grpclog.Infof("lbBalancer: handle SubConn state change: %p, %v", sc, s) - lb.mu.Lock() - defer lb.mu.Unlock() - - oldS, ok := lb.scStates[sc] - if !ok { - grpclog.Infof("lbBalancer: got state changes for an unknown SubConn: %p, %v", sc, s) - return - } - lb.scStates[sc] = s - switch s { - case connectivity.Idle: - sc.Connect() - case connectivity.Shutdown: - // When an address was removed by resolver, b called RemoveSubConn but - // kept the sc's state in scStates. Remove state for this sc here. - delete(lb.scStates, sc) - } - - oldAggrState := lb.state - lb.state = lb.csEvltr.recordTransition(oldS, s) - - // Regenerate picker when one of the following happens: - // - this sc became ready from not-ready - // - this sc became not-ready from ready - // - the aggregated state of balancer became TransientFailure from non-TransientFailure - // - the aggregated state of balancer became non-TransientFailure from TransientFailure - if (oldS == connectivity.Ready) != (s == connectivity.Ready) || - (lb.state == connectivity.TransientFailure) != (oldAggrState == connectivity.TransientFailure) { - lb.regeneratePicker() - } - - lb.cc.UpdateBalancerState(lb.state, lb.picker) -} - -// fallbackToBackendsAfter blocks for fallbackTimeout and falls back to use -// resolved backends (backends received from resolver, not from remote balancer) -// if no connection to remote balancers was successful. -func (lb *lbBalancer) fallbackToBackendsAfter(fallbackTimeout time.Duration) { - timer := time.NewTimer(fallbackTimeout) - defer timer.Stop() - select { - case <-timer.C: - case <-lb.doneCh: - return - } - lb.mu.Lock() - if lb.serverListReceived { - lb.mu.Unlock() - return - } - lb.fallbackTimerExpired = true - lb.refreshSubConns(lb.resolvedBackendAddrs) - lb.mu.Unlock() -} - -// HandleResolvedAddrs sends the updated remoteLB addresses to remoteLB -// clientConn. The remoteLB clientConn will handle creating/removing remoteLB -// connections. -func (lb *lbBalancer) HandleResolvedAddrs(addrs []resolver.Address, err error) { - grpclog.Infof("lbBalancer: handleResolvedResult: %+v", addrs) - if len(addrs) <= 0 { - return - } - - var remoteBalancerAddrs, backendAddrs []resolver.Address - for _, a := range addrs { - if a.Type == resolver.GRPCLB { - remoteBalancerAddrs = append(remoteBalancerAddrs, a) - } else { - backendAddrs = append(backendAddrs, a) - } - } - - if lb.ccRemoteLB == nil { - if len(remoteBalancerAddrs) <= 0 { - grpclog.Errorf("grpclb: no remote balancer address is available, should never happen") - return - } - // First time receiving resolved addresses, create a cc to remote - // balancers. - lb.dialRemoteLB(remoteBalancerAddrs[0].ServerName) - // Start the fallback goroutine. - go lb.fallbackToBackendsAfter(lb.fallbackTimeout) - } - - // cc to remote balancers uses lb.manualResolver. Send the updated remote - // balancer addresses to it through manualResolver. - lb.manualResolver.NewAddress(remoteBalancerAddrs) - - lb.mu.Lock() - lb.resolvedBackendAddrs = backendAddrs - // If serverListReceived is true, connection to remote balancer was - // successful and there's no need to do fallback anymore. - // If fallbackTimerExpired is false, fallback hasn't happened yet. - if !lb.serverListReceived && lb.fallbackTimerExpired { - // This means we received a new list of resolved backends, and we are - // still in fallback mode. Need to update the list of backends we are - // using to the new list of backends. - lb.refreshSubConns(lb.resolvedBackendAddrs) - } - lb.mu.Unlock() -} - -func (lb *lbBalancer) Close() { - select { - case <-lb.doneCh: - return - default: - } - close(lb.doneCh) - if lb.ccRemoteLB != nil { - lb.ccRemoteLB.Close() - } - lb.cc.close() -} |