Fix legacy rule-set download_detour blocked by empty direct check

common/dialer/detour.go

@@ -20,17 +20,17 @@ type DetourDialer struct {
 	outboundManager         adapter.OutboundManager
 	detour                  string
 	defaultOutbound         bool
-	legacyDNSDialer bool
+	disableEmptyDirectCheck bool
 	dialer                  N.Dialer
 	initOnce                sync.Once
 	initErr                 error
 }
 
-func NewDetour(outboundManager adapter.OutboundManager, detour string, legacyDNSDialer bool) N.Dialer {
+func NewDetour(outboundManager adapter.OutboundManager, detour string, disableEmptyDirectCheck bool) N.Dialer {
 	return &DetourDialer{
 		outboundManager:         outboundManager,
 		detour:                  detour,
-		legacyDNSDialer: legacyDNSDialer,
+		disableEmptyDirectCheck: disableEmptyDirectCheck,
 	}
 }
 
@@ -66,7 +66,7 @@ func (d *DetourDialer) init() {
 	} else {
 		dialer = d.outboundManager.Default()
 	}
-	if !d.defaultOutbound && !d.legacyDNSDialer {
+	if !d.defaultOutbound && !d.disableEmptyDirectCheck {
 		if directDialer, isDirect := dialer.(DirectDialer); isDirect {
 			if directDialer.IsEmpty() {
 				d.initErr = E.New("detour to an empty direct outbound makes no sense")

common/dialer/dialer.go

@@ -23,7 +23,7 @@ type Options struct {
 	DirectResolver          bool
 	ResolverOnDetour        bool
 	NewDialer               bool
-	LegacyDNSDialer  bool
+	DisableEmptyDirectCheck bool
 	DirectOutbound          bool
 	DefaultOutbound         bool
 }
@@ -49,7 +49,7 @@ func NewWithOptions(options Options) (N.Dialer, error) {
 		if outboundManager == nil {
 			return nil, E.New("missing outbound manager")
 		}
-		dialer = NewDetour(outboundManager, dialOptions.Detour, options.LegacyDNSDialer)
+		dialer = NewDetour(outboundManager, dialOptions.Detour, options.DisableEmptyDirectCheck)
 	} else if options.DefaultOutbound {
 		outboundManager := service.FromContext[adapter.OutboundManager](options.Context)
 		if outboundManager == nil {

common/httpclient/client.go

@@ -22,6 +22,7 @@ func NewTransport(ctx context.Context, logger logger.ContextLogger, tag string,
 		DirectResolver:          options.DirectResolver,
 		ResolverOnDetour:        options.ResolveOnDetour,
 		NewDialer:               options.ResolveOnDetour,
+		DisableEmptyDirectCheck: options.DisableEmptyDirectCheck,
 		DefaultOutbound:         options.DefaultOutbound,
 	})
 	if err != nil {

option/http.go

@@ -33,6 +33,7 @@ type _HTTPClientOptions struct {
 	HTTP2Options            HTTP2Options         `json:"-"`
 	HTTP3Options            QUICOptions          `json:"-"`
 	DefaultOutbound         bool                 `json:"-"`
+	DisableEmptyDirectCheck bool                 `json:"-"`
 	ResolveOnDetour         bool                 `json:"-"`
 	DirectResolver          bool                 `json:"-"`
 	OutboundTLSOptionsContainer

route/rule/rule_set_remote.go

@@ -294,11 +294,12 @@ func (s *RemoteRuleSet) resolveTransport() (adapter.HTTPTransport, error) {
 	}
 	if s.options.RemoteOptions.DownloadDetour != "" { //nolint:staticcheck
 		deprecated.Report(s.ctx, deprecated.OptionLegacyRuleSetDownloadDetour)
-		var httpClientOptions option.HTTPClientOptions
-		httpClientOptions.DialerOptions = option.DialerOptions{
+		return httpClientManager.ResolveTransport(s.ctx, s.logger, option.HTTPClientOptions{
+			DialerOptions: option.DialerOptions{
 				Detour: s.options.RemoteOptions.DownloadDetour, //nolint:staticcheck
-		}
-		return httpClientManager.ResolveTransport(s.ctx, s.logger, httpClientOptions)
+			},
+			DisableEmptyDirectCheck: true,
+		})
 	}
 	defaultTransport := httpClientManager.DefaultTransport()
 	if defaultTransport == nil {