Golang加权轮询负载均衡的实现_Golang_

 package load_balance import ( "errors" "strconv" ) type WeightRoundRobinBalance struct { curIndex int rss []*WeightNode rsw []int //观察主体 conf LoadBalanceConf } // 配置主题 type LoadBalanceConf interface { GetConf() []string WatchConf() UpdateConf(conf []string) } type WeightNode struct { addr string // 服务器地址 weight int //权重值 currentWeight int //节点当前权重 effectiveWeight int //有效权重 } func (r *WeightRoundRobinBalance) Add(params ...string) error { if len(params) != 2 { return errors.New("param len need 2") } parInt, err := strconv.ParseInt(params[1], 10, 64) if err != nil { return err } node := &WeightNode{addr: params[0], weight: int(parInt)} node.effectiveWeight = node.weight r.rss = append(r.rss, node) return nil } func (r *WeightRoundRobinBalance) Next() string { total := 0 var best *WeightNode for i := 0; i < len(r.rss); i++ { w := r.rss[i] //step 1 统计所有有效权重之和 total += w.effectiveWeight //step 2 变更节点临时权重为的节点临时权重+节点有效权重 w.currentWeight += w.effectiveWeight //step 3 有效权重默认与权重相同，通讯异常时-1, 通讯成功+1，直到恢复到weight大小 if w.effectiveWeight < w.weight { w.effectiveWeight++ } //step 4 选择最大临时权重点节点 if best == nil || w.currentWeight > best.currentWeight { best = w } } if best == nil { return "" } //step 5 变更临时权重为 临时权重-有效权重之和 best.currentWeight -= total return best.addr } func (r *WeightRoundRobinBalance) Get(key string) (string, error) { return r.Next(), nil } func (r *WeightRoundRobinBalance) SetConf(conf LoadBalanceConf) { r.conf = conf }

 package load_balance import ( "fmt" "testing" ) func TestLB(t *testing.T) { rb := &WeightRoundRobinBalance{} rb.Add("127.0.0.1:2003", "4") //0 // rb.Add("127.0.0.1:2004", "3") //1 rb.Add("127.0.0.1:2005", "2") //2 fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) fmt.Println(rb.Next()) }