增加loadbalance

Author: xfali

lb/loadbalance.go

@@ -0,0 +1,52 @@
+// Copyright (C) 2019-2020, Xiongfa Li.
+// @author xiongfa.li
+// @version V1.0
+// Description: 
+
+package lb
+
+import (
+	"math/rand"
+)
+
+type LoadBalance interface {
+	Select() interface{}
+}
+
+type BaseLoadBalance struct {
+	invokers []interface{}
+}
+
+func (lb *BaseLoadBalance) AddFactory(invokers ...interface{}) {
+	lb.invokers = append(lb.invokers, invokers...)
+}
+
+type RandomLoadBalance struct {
+	BaseLoadBalance
+	rand rand.Rand
+}
+
+func (lb *RandomLoadBalance) Select() interface{} {
+	size := len(lb.invokers)
+	if size == 0 {
+		return nil
+	}
+
+	return lb.invokers[lb.rand.Intn(size-1)]
+}
+
+type RoundRobbinLoadBalance struct {
+	BaseLoadBalance
+	i int
+}
+
+func (lb *RoundRobbinLoadBalance) Select() interface{} {
+	size := len(lb.invokers)
+	if size == 0 {
+		return nil
+	}
+
+	fac := lb.invokers[lb.i]
+	lb.i = (lb.i + 1) % size
+	return fac
+}