diff options
author | JoramWilander <jwawilander@gmail.com> | 2018-07-10 15:01:43 -0400 |
---|---|---|
committer | JoramWilander <jwawilander@gmail.com> | 2018-07-10 15:01:43 -0400 |
commit | 6c7dc2d29ccac5f9925402f6be1a4c2a3c46c005 (patch) | |
tree | 5564a47257bf6e85aaef711980c5b0fcb4d07dcc /vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go | |
parent | c042ffa460296587579aff54b157a5109e022f7e (diff) | |
parent | 1e1a5e5e85240f25c4faddcb24c5a29a915fe6e4 (diff) | |
download | chat-6c7dc2d29ccac5f9925402f6be1a4c2a3c46c005.tar.gz chat-6c7dc2d29ccac5f9925402f6be1a4c2a3c46c005.tar.bz2 chat-6c7dc2d29ccac5f9925402f6be1a4c2a3c46c005.zip |
Merge branch 'plugins-2'
Diffstat (limited to 'vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go')
-rw-r--r-- | vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go b/vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go new file mode 100644 index 000000000..2eda0a1c2 --- /dev/null +++ b/vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go @@ -0,0 +1,79 @@ +/* + * + * 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 roundrobin defines a roundrobin balancer. Roundrobin balancer is +// installed as one of the default balancers in gRPC, users don't need to +// explicitly install this balancer. +package roundrobin + +import ( + "sync" + + "golang.org/x/net/context" + "google.golang.org/grpc/balancer" + "google.golang.org/grpc/balancer/base" + "google.golang.org/grpc/grpclog" + "google.golang.org/grpc/resolver" +) + +// Name is the name of round_robin balancer. +const Name = "round_robin" + +// newBuilder creates a new roundrobin balancer builder. +func newBuilder() balancer.Builder { + return base.NewBalancerBuilder(Name, &rrPickerBuilder{}) +} + +func init() { + balancer.Register(newBuilder()) +} + +type rrPickerBuilder struct{} + +func (*rrPickerBuilder) Build(readySCs map[resolver.Address]balancer.SubConn) balancer.Picker { + grpclog.Infof("roundrobinPicker: newPicker called with readySCs: %v", readySCs) + var scs []balancer.SubConn + for _, sc := range readySCs { + scs = append(scs, sc) + } + return &rrPicker{ + subConns: scs, + } +} + +type rrPicker struct { + // subConns is the snapshot of the roundrobin balancer when this picker was + // created. The slice is immutable. Each Get() will do a round robin + // selection from it and return the selected SubConn. + subConns []balancer.SubConn + + mu sync.Mutex + next int +} + +func (p *rrPicker) Pick(ctx context.Context, opts balancer.PickOptions) (balancer.SubConn, func(balancer.DoneInfo), error) { + if len(p.subConns) <= 0 { + return nil, nil, balancer.ErrNoSubConnAvailable + } + + p.mu.Lock() + sc := p.subConns[p.next] + p.next = (p.next + 1) % len(p.subConns) + p.mu.Unlock() + return sc, nil, nil +} |