| /* |
| * |
| * Copyright 2019 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 grpclb |
| |
| import ( |
| "encoding/json" |
| |
| "google.golang.org/grpc" |
| "google.golang.org/grpc/balancer/roundrobin" |
| "google.golang.org/grpc/serviceconfig" |
| ) |
| |
| const ( |
| roundRobinName = roundrobin.Name |
| pickFirstName = grpc.PickFirstBalancerName |
| ) |
| |
| type grpclbServiceConfig struct { |
| serviceconfig.LoadBalancingConfig |
| ChildPolicy *[]map[string]json.RawMessage |
| } |
| |
| func (b *lbBuilder) ParseConfig(lbConfig json.RawMessage) (serviceconfig.LoadBalancingConfig, error) { |
| ret := &grpclbServiceConfig{} |
| if err := json.Unmarshal(lbConfig, ret); err != nil { |
| return nil, err |
| } |
| return ret, nil |
| } |
| |
| func childIsPickFirst(sc *grpclbServiceConfig) bool { |
| if sc == nil { |
| return false |
| } |
| childConfigs := sc.ChildPolicy |
| if childConfigs == nil { |
| return false |
| } |
| for _, childC := range *childConfigs { |
| // If round_robin exists before pick_first, return false |
| if _, ok := childC[roundRobinName]; ok { |
| return false |
| } |
| // If pick_first is before round_robin, return true |
| if _, ok := childC[pickFirstName]; ok { |
| return true |
| } |
| } |
| return false |
| } |