| /* |
| * 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 ringhash |
| |
| import ( |
| "math" |
| ) |
| |
| import ( |
| "github.com/dubbogo/gost/hash/consistent" |
| ) |
| |
| import ( |
| "github.com/apache/dubbo-go-pixiu/pixiu/pkg/cluster/loadbalancer" |
| "github.com/apache/dubbo-go-pixiu/pixiu/pkg/logger" |
| "github.com/apache/dubbo-go-pixiu/pixiu/pkg/model" |
| ) |
| |
| func init() { |
| loadbalancer.RegisterLoadBalancer(model.LoadBalancerRingHashing, RingHashing{}) |
| loadbalancer.RegisterConsistentHashInit(model.LoadBalancerRingHashing, NewRingHash) |
| } |
| |
| func NewRingHash(config model.ConsistentHash, endpoints []*model.Endpoint) model.LbConsistentHash { |
| var ops []consistent.Option |
| |
| if config.ReplicaNum != 0 { |
| ops = append(ops, consistent.WithReplicaNum(config.ReplicaNum)) |
| } |
| |
| if config.MaxVnodeNum != 0 { |
| ops = append(ops, consistent.WithMaxVnodeNum(int(config.MaxVnodeNum))) |
| } else { |
| config.MaxVnodeNum = math.MinInt32 |
| } |
| |
| h := consistent.NewConsistentHash(ops...) |
| for _, endpoint := range endpoints { |
| h.Add(endpoint.GetHost()) |
| } |
| return h |
| } |
| |
| type RingHashing struct{} |
| |
| func (r RingHashing) Handler(c *model.ClusterConfig, policy model.LbPolicy) *model.Endpoint { |
| u := c.ConsistentHash.Hash.Hash(policy.GenerateHash()) |
| hash, err := c.ConsistentHash.Hash.GetHash(u) |
| if err != nil { |
| logger.Warnf("[dubbo-go-pixiu] error of getting from ring hash: %v", err) |
| return nil |
| } |
| |
| endpoints := c.GetEndpoint(true) |
| |
| for _, endpoint := range endpoints { |
| if endpoint.GetHost() == hash { |
| return endpoint |
| } |
| } |
| |
| if len(endpoints) == 0 { |
| return nil |
| } |
| |
| return endpoints[0] |
| } |