| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 random |
| |
| import ( |
| "math/rand" |
| "time" |
| ) |
| |
| import ( |
| "dubbo.apache.org/dubbo-go/v3/common" |
| "dubbo.apache.org/dubbo-go/v3/common/extension" |
| "dubbo.apache.org/dubbo-go/v3/registry" |
| "dubbo.apache.org/dubbo-go/v3/registry/servicediscovery/instance" |
| ) |
| |
| func init() { |
| rand.Seed(time.Now().UnixNano()) |
| extension.SetServiceInstanceSelector("random", NewRandomServiceInstanceSelector) |
| } |
| |
| // the ServiceInstanceSelector implementation based on Random algorithm |
| type RandomServiceInstanceSelector struct{} |
| |
| func NewRandomServiceInstanceSelector() instance.ServiceInstanceSelector { |
| return &RandomServiceInstanceSelector{} |
| } |
| |
| func (r *RandomServiceInstanceSelector) Select(url *common.URL, serviceInstances []registry.ServiceInstance) registry.ServiceInstance { |
| if len(serviceInstances) == 0 { |
| return nil |
| } |
| if len(serviceInstances) == 1 { |
| return serviceInstances[0] |
| } |
| index := rand.Intn(len(serviceInstances)) |
| return serviceInstances[index] |
| } |