Add new admin panel, failover, dns fallback, providers, limiters. Update XHTTP

protocol/failover/strategy.go

@@ -0,0 +1,70 @@
+package failover
+
+import (
+	"context"
+	"net"
+	"time"
+
+	"github.com/sagernet/sing-box/adapter"
+	E "github.com/sagernet/sing/common/exceptions"
+	"github.com/sagernet/sing/common/logger"
+	M "github.com/sagernet/sing/common/metadata"
+)
+
+type DialStrategy = func(ctx context.Context, network string, destination M.Socksaddr) (net.Conn, error)
+
+func cycleStrategy(outbounds []adapter.Outbound, logger logger.ContextLogger, delay time.Duration) DialStrategy {
+	return func(ctx context.Context, network string, destination M.Socksaddr) (net.Conn, error) {
+		for {
+			for _, outbound := range outbounds {
+				conn, err := outbound.DialContext(ctx, network, destination)
+				if err != nil {
+					logger.InfoContext(ctx, err)
+					if delay > 0 {
+						select {
+						case <-time.After(delay):
+						case <-ctx.Done():
+							return nil, ctx.Err()
+						}
+					}
+					continue
+				}
+				return conn, nil
+			}
+		}
+	}
+}
+
+func sequentialStrategy(outbounds []adapter.Outbound, logger logger.ContextLogger, delay time.Duration) DialStrategy {
+	return func(ctx context.Context, network string, destination M.Socksaddr) (net.Conn, error) {
+		var err error
+		for _, outbound := range outbounds {
+			var conn net.Conn
+			conn, err = outbound.DialContext(ctx, network, destination)
+			if err != nil {
+				logger.InfoContext(ctx, err)
+				if delay > 0 {
+					select {
+					case <-time.After(delay):
+					case <-ctx.Done():
+						return nil, ctx.Err()
+					}
+				}
+				continue
+			}
+			return conn, nil
+		}
+		return nil, err
+	}
+}
+
+func CreateStrategy(strategy string, outbounds []adapter.Outbound, logger logger.ContextLogger, delay time.Duration) (DialStrategy, error) {
+	switch strategy {
+	case "cycle":
+		return cycleStrategy(outbounds, logger, delay), nil
+	case "sequential", "":
+		return sequentialStrategy(outbounds, logger, delay), nil
+	default:
+		return nil, E.New("strategy not found: ", strategy)
+	}
+}