fix(web): install the share-link provider before the panel serves (#6914)

The panel started answering requests before the share-link generator was
registered, so an "all links", client sub-links or Telegram link request that
arrived during start-up got "sub link provider not registered". NewServer now
takes the provider and installs it before anything listens, and the provider
registry is guarded by a lock, since start-up writes it while requests read it.

internal/web/node_contract_test.go

@@ -43,7 +43,7 @@ func startContractNode(t *testing.T) *nodeUnderContract {
 	t.Cleanup(func() { runtime.SetManager(prevMgr) })
 
 	previous := global.GetWebServer()
-	s := NewServer()
+	s := NewServer(nil)
 	s.cron = cron.New(cron.WithLocation(time.Local), cron.WithSeconds())
 	global.SetWebServer(s)
 	t.Cleanup(func() {

internal/web/routes_contract_test.go

@@ -47,7 +47,7 @@ func registeredContractRoutes(t *testing.T) map[string]bool {
 	dbtest.InitDB(t, filepath.Join(t.TempDir(), "x-ui.db"))
 
 	previous := global.GetWebServer()
-	s := NewServer()
+	s := NewServer(nil)
 	s.cron = cron.New(cron.WithLocation(time.Local), cron.WithSeconds())
 	global.SetWebServer(s)
 	t.Cleanup(func() {

internal/web/service/inbound_sublink.go

@@ -1,6 +1,8 @@
 package service
 
 import (
+	"sync"
+
 	"github.com/mhsanaei/3x-ui/v3/internal/database/model"
 	"github.com/mhsanaei/3x-ui/v3/internal/util/common"
 )
@@ -11,35 +13,50 @@ type SubLinkProvider interface {
 	LinksForInbounds(host string, inbounds []*model.Inbound) []string
 }
 
-var registeredSubLinkProvider SubLinkProvider
+var (
+	subLinkProviderMu         sync.RWMutex
+	registeredSubLinkProvider SubLinkProvider
+)
 
 func RegisterSubLinkProvider(p SubLinkProvider) {
+	subLinkProviderMu.Lock()
+	defer subLinkProviderMu.Unlock()
 	registeredSubLinkProvider = p
 }
 
+// subLinkProvider guards the registry: startup writes it while link requests read it.
+func subLinkProvider() SubLinkProvider {
+	subLinkProviderMu.RLock()
+	defer subLinkProviderMu.RUnlock()
+	return registeredSubLinkProvider
+}
+
 func (s *InboundService) GetSubLinks(host, subId string) ([]string, error) {
-	if registeredSubLinkProvider == nil {
+	provider := subLinkProvider()
+	if provider == nil {
 		return nil, common.NewError("sub link provider not registered")
 	}
-	return registeredSubLinkProvider.SubLinksForSubId(host, subId)
+	return provider.SubLinksForSubId(host, subId)
 }
 
 func (s *InboundService) GetAllInboundLinks(host string, userId int) ([]string, error) {
-	if registeredSubLinkProvider == nil {
+	provider := subLinkProvider()
+	if provider == nil {
 		return nil, common.NewError("sub link provider not registered")
 	}
 	inbounds, err := s.GetInbounds(userId)
 	if err != nil {
 		return nil, err
 	}
-	return registeredSubLinkProvider.LinksForInbounds(host, inbounds), nil
+	return provider.LinksForInbounds(host, inbounds), nil
 }
 
 func (s *InboundService) GetAllClientLinks(host string, email string) ([]string, error) {
 	if email == "" {
 		return nil, common.NewError("client email is required")
 	}
-	if registeredSubLinkProvider == nil {
+	provider := subLinkProvider()
+	if provider == nil {
 		return nil, common.NewError("sub link provider not registered")
 	}
 	rec, err := s.clientService.GetRecordByEmail(nil, email)
@@ -56,7 +73,7 @@ func (s *InboundService) GetAllClientLinks(host string, email string) ([]string,
 		if getErr != nil {
 			return nil, getErr
 		}
-		links = append(links, registeredSubLinkProvider.LinksForClient(host, inbound, email)...)
+		links = append(links, provider.LinksForClient(host, inbound, email)...)
 	}
 	return links, nil
 }

internal/web/service/sublink_registry_test.go

@@ -0,0 +1,44 @@
+package service
+
+import (
+	"sync"
+	"testing"
+
+	"github.com/mhsanaei/3x-ui/v3/internal/database/model"
+)
+
+type fakeSubLinkProvider struct {
+	links []string
+}
+
+func (f fakeSubLinkProvider) SubLinksForSubId(host, subId string) ([]string, error) {
+	return f.links, nil
+}
+
+func (f fakeSubLinkProvider) LinksForClient(host string, inbound *model.Inbound, email string) []string {
+	return f.links
+}
+
+func (f fakeSubLinkProvider) LinksForInbounds(host string, inbounds []*model.Inbound) []string {
+	return f.links
+}
+
+// Startup writes the provider registry while link requests read it; under -race an
+// unguarded registry fails here.
+func TestSubLinkProviderRegistrationIsRaceFree(t *testing.T) {
+	t.Cleanup(func() { RegisterSubLinkProvider(nil) })
+
+	var wg sync.WaitGroup
+	for range 8 {
+		wg.Add(2)
+		go func() {
+			defer wg.Done()
+			RegisterSubLinkProvider(fakeSubLinkProvider{links: []string{"vless://example"}})
+		}()
+		go func() {
+			defer wg.Done()
+			_, _ = (&InboundService{}).GetSubLinks("panel.example", "subid")
+		}()
+	}
+	wg.Wait()
+}

internal/web/web.go

@@ -138,8 +138,12 @@ type Server struct {
 	cancel context.CancelFunc
 }
 
-// NewServer creates a new web server instance with a cancellable context.
+// NewServer installs the share-link provider before anything serves, so an early link request
-func NewServer() *Server {
+// no longer gets "sub link provider not registered".
+func NewServer(subLinkProvider service.SubLinkProvider) *Server {
+	if subLinkProvider != nil {
+		service.RegisterSubLinkProvider(subLinkProvider)
+	}
 	ctx, cancel := context.WithCancel(context.Background())
 	return &Server{
 		ctx:    ctx,
@@ -550,11 +554,12 @@ func (s *Server) start(restartXray bool, startTgBot bool) (err error) {
 	// add/update/delete to either the local xray or a remote node panel.
 	// The closures bridge into XrayService (which owns the running xray
 	// process state) without forcing the runtime package to import service.
-	runtime.SetManager(runtime.NewManager(runtime.LocalDeps{
+	mgr := runtime.NewManager(runtime.LocalDeps{
 		APIPort:        func() int { return s.xrayService.GetXrayAPIPort() },
 		SetNeedRestart: func() { s.xrayService.SetToNeedRestart() },
-	}))
+	})
-	runtime.GetManager().SetNodeEgressResolver(&s.settingService)
+	runtime.SetManager(mgr)
+	mgr.SetNodeEgressResolver(&s.settingService)
 	// Supply the master client certificate for nodes in mtls mode. Issued lazily
 	// from the node CA on first use; runtime stays free of a service import.
 	runtime.SetMasterClientCertProvider(func() (tls.Certificate, error) {

internal/web/web_shutdown_test.go

@@ -10,7 +10,7 @@ import (
 
 func TestServerStopWhenXrayNotRunningSucceeds(t *testing.T) {
 	t.Setenv("XUI_DB_FOLDER", t.TempDir())
-	s := NewServer()
+	s := NewServer(nil)
 	if err := s.Stop(); err != nil {
 		t.Fatalf("expected nil error when stopping server with unstarted xray, got: %v", err)
 	}
@@ -18,7 +18,7 @@ func TestServerStopWhenXrayNotRunningSucceeds(t *testing.T) {
 
 func TestServerStopPanelOnlyWithPreclosedListenerSucceeds(t *testing.T) {
 	t.Setenv("XUI_DB_FOLDER", t.TempDir())
-	s := NewServer()
+	s := NewServer(nil)
 	ln, err := net.Listen("tcp", "127.0.0.1:0")
 	if err != nil {
 		t.Fatalf("net.Listen failed: %v", err)

internal/web/web_sublink_test.go

@@ -0,0 +1,40 @@
+package web
+
+import (
+	"testing"
+
+	"github.com/mhsanaei/3x-ui/v3/internal/database/model"
+	"github.com/mhsanaei/3x-ui/v3/internal/web/service"
+)
+
+type fakeSubLinkProvider struct {
+	links []string
+}
+
+func (f fakeSubLinkProvider) SubLinksForSubId(host, subId string) ([]string, error) {
+	return f.links, nil
+}
+
+func (f fakeSubLinkProvider) LinksForClient(host string, inbound *model.Inbound, email string) []string {
+	return f.links
+}
+
+func (f fakeSubLinkProvider) LinksForInbounds(host string, inbounds []*model.Inbound) []string {
+	return f.links
+}
+
+// A link request can arrive as soon as the panel serves, so NewServer must install the provider.
+func TestNewServerInstallsTheShareLinkProviderBeforeServing(t *testing.T) {
+	service.RegisterSubLinkProvider(nil)
+	t.Cleanup(func() { service.RegisterSubLinkProvider(nil) })
+
+	NewServer(fakeSubLinkProvider{links: []string{"vless://example"}})
+
+	links, err := (&service.InboundService{}).GetSubLinks("panel.example", "subid")
+	if err != nil {
+		t.Fatalf("the share-link provider must be installed before the panel serves: %v", err)
+	}
+	if len(links) != 1 || links[0] != "vless://example" {
+		t.Fatalf("links = %v, want the provider's links", links)
+	}
+}

internal/web/web_tuic_shutdown_test.go

@@ -74,7 +74,7 @@ func TestGracefulShutdownPersistsFinalTuicTraffic(t *testing.T) {
 		t.Fatal("TUIC listener did not start")
 	}
 
-	if err := NewServer().Stop(); err != nil {
+	if err := NewServer(nil).Stop(); err != nil {
 		t.Fatalf("graceful server shutdown: %v", err)
 	}
 

main.go

@@ -121,7 +121,7 @@ func runWebServer() {
 		log.Printf("No panel user existed, so one was generated. Username: %s  Password: %s  (shown once; change it in Panel Settings)", username, password)
 	}
 
-	server := web.NewServer()
+	server := web.NewServer(sub.NewLinkProvider())
 	global.SetWebServer(server)
 	err = server.Start()
 	if err != nil {
@@ -129,7 +129,6 @@ func runWebServer() {
 	}
 
 	sub.SetDistFS(web.EmbeddedDist())
-	service.RegisterSubLinkProvider(sub.NewLinkProvider())
 	subServer := sub.NewServer()
 	global.SetSubServer(subServer)
 	err = subServer.Start()
@@ -183,7 +182,7 @@ func runWebServer() {
 				logger.Debug("Error stopping sub server:", err)
 			}
 
-			server = web.NewServer()
+			server = web.NewServer(sub.NewLinkProvider())
 			global.SetWebServer(server)
 			err = server.StartPanelOnly()
 			if err != nil {