Xray-core/app/router/balancing.go
Hossin Asaadi 01c14a5994
add Round-Robin Strategy to balancer (#2844)
* add Round-Robin Strategy

* clean up
2023-12-24 15:29:10 -05:00

87 lines
1.7 KiB
Go

package router
import (
"context"
sync "sync"
"github.com/xtls/xray-core/common/dice"
"github.com/xtls/xray-core/features/extension"
"github.com/xtls/xray-core/features/outbound"
)
type BalancingStrategy interface {
PickOutbound([]string) string
}
type RandomStrategy struct{}
func (s *RandomStrategy) PickOutbound(tags []string) string {
n := len(tags)
if n == 0 {
panic("0 tags")
}
return tags[dice.Roll(n)]
}
type RoundRobinStrategy struct {
mu sync.Mutex
tags []string
index int
roundRobin *RoundRobinStrategy
}
func NewRoundRobin(tags []string) *RoundRobinStrategy {
return &RoundRobinStrategy{
tags: tags,
}
}
func (r *RoundRobinStrategy) NextTag() string {
r.mu.Lock()
defer r.mu.Unlock()
tags := r.tags[r.index]
r.index = (r.index + 1) % len(r.tags)
return tags
}
func (s *RoundRobinStrategy) PickOutbound(tags []string) string {
if len(tags) == 0 {
panic("0 tags")
}
if s.roundRobin == nil {
s.roundRobin = NewRoundRobin(tags)
}
tag := s.roundRobin.NextTag()
return tag
}
type Balancer struct {
selectors []string
strategy BalancingStrategy
ohm outbound.Manager
}
func (b *Balancer) PickOutbound() (string, error) {
hs, ok := b.ohm.(outbound.HandlerSelector)
if !ok {
return "", newError("outbound.Manager is not a HandlerSelector")
}
tags := hs.Select(b.selectors)
if len(tags) == 0 {
return "", newError("no available outbounds selected")
}
tag := b.strategy.PickOutbound(tags)
if tag == "" {
return "", newError("balancing strategy returns empty tag")
}
return tag, nil
}
func (b *Balancer) InjectContext(ctx context.Context) {
if contextReceiver, ok := b.strategy.(extension.ContextReceiver); ok {
contextReceiver.InjectContext(ctx)
}
}