chore: 初始化 Cloudreve 源码仓库

pkg/balancer/balancer.go

@@ -0,0 +1,15 @@
+package balancer
+
+type Balancer interface {
+	NextPeer(nodes interface{}) (error, interface{})
+}
+
+// NewBalancer 根据策略标识返回新的负载均衡器
+func NewBalancer(strategy string) Balancer {
+	switch strategy {
+	case "RoundRobin":
+		return &RoundRobin{}
+	default:
+		return &RoundRobin{}
+	}
+}

pkg/balancer/balancer_test.go

@@ -0,0 +1,12 @@
+package balancer
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestNewBalancer(t *testing.T) {
+	a := assert.New(t)
+	a.NotNil(NewBalancer(""))
+	a.IsType(&RoundRobin{}, NewBalancer("RoundRobin"))
+}

pkg/balancer/errors.go

@@ -0,0 +1,8 @@
+package balancer
+
+import "errors"
+
+var (
+	ErrInputNotSlice   = errors.New("Input value is not silice")
+	ErrNoAvaliableNode = errors.New("No nodes avaliable")
+)

pkg/balancer/roundrobin.go

@@ -0,0 +1,30 @@
+package balancer
+
+import (
+	"reflect"
+	"sync/atomic"
+)
+
+type RoundRobin struct {
+	current uint64
+}
+
+// NextPeer 返回轮盘的下一节点
+func (r *RoundRobin) NextPeer(nodes interface{}) (error, interface{}) {
+	v := reflect.ValueOf(nodes)
+	if v.Kind() != reflect.Slice {
+		return ErrInputNotSlice, nil
+	}
+
+	if v.Len() == 0 {
+		return ErrNoAvaliableNode, nil
+	}
+
+	next := r.NextIndex(v.Len())
+	return nil, v.Index(next).Interface()
+}
+
+// NextIndex 返回下一个节点下标
+func (r *RoundRobin) NextIndex(total int) int {
+	return int(atomic.AddUint64(&r.current, uint64(1)) % uint64(total))
+}

pkg/balancer/roundrobin_test.go

@@ -0,0 +1,42 @@
+package balancer
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestRoundRobin_NextIndex(t *testing.T) {
+	a := assert.New(t)
+	r := &RoundRobin{}
+	total := 5
+	for i := 1; i < total; i++ {
+		a.Equal(i, r.NextIndex(total))
+	}
+	for i := 0; i < total; i++ {
+		a.Equal(i, r.NextIndex(total))
+	}
+}
+
+func TestRoundRobin_NextPeer(t *testing.T) {
+	a := assert.New(t)
+	r := &RoundRobin{}
+
+	// not slice
+	{
+		err, _ := r.NextPeer("s")
+		a.Equal(ErrInputNotSlice, err)
+	}
+
+	// no nodes
+	{
+		err, _ := r.NextPeer([]string{})
+		a.Equal(ErrNoAvaliableNode, err)
+	}
+
+	// pass
+	{
+		err, res := r.NextPeer([]string{"a"})
+		a.NoError(err)
+		a.Equal("a", res.(string))
+	}
+}