120728e1f7
The pickfirstBalancer and baseBalancer are logging a lot of messages under normal operation. Those messages can not be associated to a server connection because no connection address is part of the messages. They are messages that are only useful when debugging issues. Only log them when the verbose level is at least 2, to reduce the amount of log messages under normal operation.
119 lines
2.9 KiB
Go
119 lines
2.9 KiB
Go
/*
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*
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* Copyright 2017 gRPC authors.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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*/
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package grpc
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import (
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"context"
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"google.golang.org/grpc/balancer"
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"google.golang.org/grpc/connectivity"
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"google.golang.org/grpc/grpclog"
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"google.golang.org/grpc/resolver"
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)
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// PickFirstBalancerName is the name of the pick_first balancer.
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const PickFirstBalancerName = "pick_first"
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func newPickfirstBuilder() balancer.Builder {
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return &pickfirstBuilder{}
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}
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type pickfirstBuilder struct{}
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func (*pickfirstBuilder) Build(cc balancer.ClientConn, opt balancer.BuildOptions) balancer.Balancer {
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return &pickfirstBalancer{cc: cc}
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}
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func (*pickfirstBuilder) Name() string {
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return PickFirstBalancerName
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}
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type pickfirstBalancer struct {
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cc balancer.ClientConn
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sc balancer.SubConn
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}
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func (b *pickfirstBalancer) HandleResolvedAddrs(addrs []resolver.Address, err error) {
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if err != nil {
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if grpclog.V(2) {
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grpclog.Infof("pickfirstBalancer: HandleResolvedAddrs called with error %v", err)
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}
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return
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}
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if b.sc == nil {
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b.sc, err = b.cc.NewSubConn(addrs, balancer.NewSubConnOptions{})
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if err != nil {
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//TODO(yuxuanli): why not change the cc state to Idle?
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if grpclog.V(2) {
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grpclog.Errorf("pickfirstBalancer: failed to NewSubConn: %v", err)
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}
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return
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}
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b.cc.UpdateBalancerState(connectivity.Idle, &picker{sc: b.sc})
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b.sc.Connect()
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} else {
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b.sc.UpdateAddresses(addrs)
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b.sc.Connect()
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}
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}
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func (b *pickfirstBalancer) HandleSubConnStateChange(sc balancer.SubConn, s connectivity.State) {
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if grpclog.V(2) {
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grpclog.Infof("pickfirstBalancer: HandleSubConnStateChange: %p, %v", sc, s)
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}
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if b.sc != sc {
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if grpclog.V(2) {
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grpclog.Infof("pickfirstBalancer: ignored state change because sc is not recognized")
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}
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return
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}
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if s == connectivity.Shutdown {
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b.sc = nil
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return
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}
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switch s {
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case connectivity.Ready, connectivity.Idle:
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b.cc.UpdateBalancerState(s, &picker{sc: sc})
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case connectivity.Connecting:
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b.cc.UpdateBalancerState(s, &picker{err: balancer.ErrNoSubConnAvailable})
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case connectivity.TransientFailure:
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b.cc.UpdateBalancerState(s, &picker{err: balancer.ErrTransientFailure})
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}
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}
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func (b *pickfirstBalancer) Close() {
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}
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type picker struct {
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err error
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sc balancer.SubConn
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}
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func (p *picker) Pick(ctx context.Context, opts balancer.PickOptions) (balancer.SubConn, func(balancer.DoneInfo), error) {
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if p.err != nil {
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return nil, nil, p.err
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}
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return p.sc, nil, nil
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}
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func init() {
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balancer.Register(newPickfirstBuilder())
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}
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