Feature: add experimental provider

adapters/outboundgroup/loadbalance.go

@@ -0,0 +1,125 @@
+package outboundgroup
+
+import (
+	"context"
+	"encoding/json"
+	"net"
+
+	"github.com/Dreamacro/clash/adapters/outbound"
+	"github.com/Dreamacro/clash/adapters/provider"
+	"github.com/Dreamacro/clash/common/murmur3"
+	C "github.com/Dreamacro/clash/constant"
+
+	"golang.org/x/net/publicsuffix"
+)
+
+type LoadBalance struct {
+	*outbound.Base
+	maxRetry  int
+	providers []provider.ProxyProvider
+}
+
+func getKey(metadata *C.Metadata) string {
+	if metadata.Host != "" {
+		// ip host
+		if ip := net.ParseIP(metadata.Host); ip != nil {
+			return metadata.Host
+		}
+
+		if etld, err := publicsuffix.EffectiveTLDPlusOne(metadata.Host); err == nil {
+			return etld
+		}
+	}
+
+	if metadata.DstIP == nil {
+		return ""
+	}
+
+	return metadata.DstIP.String()
+}
+
+func jumpHash(key uint64, buckets int32) int32 {
+	var b, j int64
+
+	for j < int64(buckets) {
+		b = j
+		key = key*2862933555777941757 + 1
+		j = int64(float64(b+1) * (float64(int64(1)<<31) / float64((key>>33)+1)))
+	}
+
+	return int32(b)
+}
+
+func (lb *LoadBalance) DialContext(ctx context.Context, metadata *C.Metadata) (c C.Conn, err error) {
+	defer func() {
+		if err == nil {
+			c.AppendToChains(lb)
+		}
+	}()
+
+	key := uint64(murmur3.Sum32([]byte(getKey(metadata))))
+	proxies := lb.proxies()
+	buckets := int32(len(proxies))
+	for i := 0; i < lb.maxRetry; i, key = i+1, key+1 {
+		idx := jumpHash(key, buckets)
+		proxy := proxies[idx]
+		if proxy.Alive() {
+			c, err = proxy.DialContext(ctx, metadata)
+			return
+		}
+	}
+	c, err = proxies[0].DialContext(ctx, metadata)
+	return
+}
+
+func (lb *LoadBalance) DialUDP(metadata *C.Metadata) (pc C.PacketConn, addr net.Addr, err error) {
+	defer func() {
+		if err == nil {
+			pc.AppendToChains(lb)
+		}
+	}()
+
+	key := uint64(murmur3.Sum32([]byte(getKey(metadata))))
+	proxies := lb.proxies()
+	buckets := int32(len(proxies))
+	for i := 0; i < lb.maxRetry; i, key = i+1, key+1 {
+		idx := jumpHash(key, buckets)
+		proxy := proxies[idx]
+		if proxy.Alive() {
+			return proxy.DialUDP(metadata)
+		}
+	}
+
+	return proxies[0].DialUDP(metadata)
+}
+
+func (lb *LoadBalance) SupportUDP() bool {
+	return true
+}
+
+func (lb *LoadBalance) proxies() []C.Proxy {
+	proxies := []C.Proxy{}
+	for _, provider := range lb.providers {
+		proxies = append(proxies, provider.Proxies()...)
+	}
+	return proxies
+}
+
+func (lb *LoadBalance) MarshalJSON() ([]byte, error) {
+	var all []string
+	for _, proxy := range lb.proxies() {
+		all = append(all, proxy.Name())
+	}
+	return json.Marshal(map[string]interface{}{
+		"type": lb.Type().String(),
+		"all":  all,
+	})
+}
+
+func NewLoadBalance(name string, providers []provider.ProxyProvider) *LoadBalance {
+	return &LoadBalance{
+		Base:      outbound.NewBase(name, C.LoadBalance, false),
+		maxRetry:  3,
+		providers: providers,
+	}
+}