feat(config): improve config reload handling and introduce async management save hook

- Refactored `ConfigReloadHook` to use `reloadConfigFromWatcher` for consistency.
- Added async `reloadConfigAfterManagementSaveAsync` to handle post-save operations.
- Introduced `ReloadConfigIfChanged` in watcher for manual trigger support.
- Enhanced config reload paths to separate auth synthesis from standard updates.
- Updated `applyConfigUpdate` logic to allow more granular reload behaviors.

Closes: router-for-me#3235

Author: luispater

internal/api/handlers/management/handler.go

@@ -411,7 +411,13 @@ func (h *Handler) persistLocked(c *gin.Context) bool {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": fmt.Sprintf("failed to save config: %v", err)})
 		return false
 	}
+	snapshot := h.reloadSnapshotConfigLocked()
 	c.JSON(http.StatusOK, gin.H{"status": "ok"})
+	var reqCtx context.Context
+	if c != nil && c.Request != nil {
+		reqCtx = c.Request.Context()
+	}
+	h.reloadConfigAfterManagementSaveAsync(reqCtx, snapshot)
 	return true
 }
 

internal/watcher/config_reload.go

@@ -40,6 +40,14 @@ func (w *Watcher) scheduleConfigReload() {
 	})
 }
 
+// ReloadConfigIfChanged runs the same config reload path used by filesystem events.
+func (w *Watcher) ReloadConfigIfChanged() {
+	if w == nil {
+		return
+	}
+	w.reloadConfigIfChanged()
+}
+
 func (w *Watcher) reloadConfigIfChanged() {
 	data, err := os.ReadFile(w.configPath)
 	if err != nil {

sdk/cliproxy/builder.go

@@ -289,8 +289,8 @@ func (b *Builder) Build() (*Service, error) {
 	service.serverOptions = append(service.serverOptions,
 		api.WithPostAuthPersistHook(service.runtimeAuthSyncHook()),
 		api.WithPluginHost(pluginHost),
-		api.WithConfigReloadHook(func(ctx context.Context, cfg *config.Config) {
-			service.applyConfigUpdate(cfg)
+		api.WithConfigReloadHook(func(_ context.Context, _ *config.Config) {
+			service.reloadConfigFromWatcher()
 		}),
 	)
 	return service, nil

sdk/cliproxy/service.go

@@ -1097,6 +1097,14 @@ func (s *Service) tryRegisterPluginModelsForAuth(ctx context.Context, a *coreaut
 }
 
 func (s *Service) applyConfigUpdate(newCfg *config.Config) {
+	s.applyConfigUpdateWithAuthSynthesis(newCfg, true)
+}
+
+func (s *Service) applyWatcherConfigUpdate(newCfg *config.Config) {
+	s.applyConfigUpdateWithAuthSynthesis(newCfg, false)
+}
+
+func (s *Service) applyConfigUpdateWithAuthSynthesis(newCfg *config.Config, synthesizeConfigAuths bool) {
 	if s == nil {
 		return
 	}
@@ -1190,10 +1198,19 @@ func (s *Service) applyConfigUpdate(newCfg *config.Config) {
 		auths:             auths,
 	})
 	ctx := coreauth.WithSkipPersist(context.Background())
-	s.registerConfigAPIKeyAuths(ctx, newCfg)
+	if synthesizeConfigAuths {
+		s.registerConfigAPIKeyAuths(ctx, newCfg)
+	}
 	s.syncPluginRuntime(ctx)
 }
 
+func (s *Service) reloadConfigFromWatcher() bool {
+	if s == nil || s.watcher == nil {
+		return false
+	}
+	return s.watcher.ReloadConfigIfChanged()
+}
+
 func (s *Service) registerConfigAPIKeyAuths(ctx context.Context, cfg *config.Config) {
 	if s == nil || s.coreManager == nil || cfg == nil {
 		return
@@ -1442,6 +1459,7 @@ func (s *Service) Run(ctx context.Context) error {
 		if errLoad := s.coreManager.Load(ctx); errLoad != nil {
 			log.Warnf("failed to load auth store: %v", errLoad)
 		}
+		s.registerConfigAPIKeyAuths(coreauth.WithSkipPersist(ctx), s.cfg)
 	}
 
 	if !homeEnabled {
@@ -1532,7 +1550,7 @@ func (s *Service) Run(ctx context.Context) error {
 
 	if !homeEnabled {
 		var watcherWrapper *WatcherWrapper
-		reloadCallback := func(newCfg *config.Config) { s.applyConfigUpdate(newCfg) }
+		reloadCallback := func(newCfg *config.Config) { s.applyWatcherConfigUpdate(newCfg) }
 
 		watcherWrapper, errCreate := s.watcherFactory(s.configPath, s.cfg.AuthDir, reloadCallback)
 		if errCreate != nil {

sdk/cliproxy/types.go

@@ -97,6 +97,7 @@ type WatcherWrapper struct {
 	dispatchRuntimeUpdate func(update watcher.AuthUpdate) bool
 	dispatchPersistedAuth func(update watcher.AuthUpdate) bool
 	setPluginAuthParser   func(parser PluginAuthParser)
+	reloadConfigIfChanged func()
 }
 
 // Start proxies to the underlying watcher Start implementation.
@@ -123,6 +124,15 @@ func (w *WatcherWrapper) SetConfig(cfg *config.Config) {
 	w.setConfig(cfg)
 }
 
+// ReloadConfigIfChanged asks the underlying watcher to reload config from disk.
+func (w *WatcherWrapper) ReloadConfigIfChanged() bool {
+	if w == nil || w.reloadConfigIfChanged == nil {
+		return false
+	}
+	w.reloadConfigIfChanged()
+	return true
+}
+
 // SetPluginAuthParser updates the plugin auth parser used by the watcher.
 func (w *WatcherWrapper) SetPluginAuthParser(parser PluginAuthParser) {
 	if w == nil || w.setPluginAuthParser == nil {

sdk/cliproxy/watcher.go

@@ -37,5 +37,8 @@ func defaultWatcherFactory(configPath, authDir string, reload func(*config.Confi
 		setPluginAuthParser: func(parser PluginAuthParser) {
 			w.SetPluginAuthParser(parser)
 		},
+		reloadConfigIfChanged: func() {
+			w.ReloadConfigIfChanged()
+		},
 	}, nil
 }