perf: cache translated chapter responses for 1 hour

Translation content is immutable once generated — add Cache-Control: public,
max-age=3600, stale-while-revalidate=86400 to handleTranslationRead so the
browser and any CDN reuse the response without hitting MinIO on repeat views.
Forward the header through the SvelteKit /api/translation/[slug]/[n] proxy
which previously stripped it by constructing a bare Content-Type-only Response.

backend/cmd/backend/main.go

@@ -199,6 +199,7 @@ func run() error {
 			BookWriter:        store,
 			AIJobStore:        store,
 			BookAdminStore:    store,
+			NotificationStore: store,
 			Log:               log,
 		},
 	)

backend/internal/backend/handlers.go

@@ -1279,6 +1279,10 @@ func (s *Server) handleTranslationRead(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// Translated chapter content is immutable once generated — cache aggressively.
+	// The browser and any intermediary (CDN, SvelteKit fetch cache) can reuse this
+	// response for 1 hour without hitting MinIO again.
+	w.Header().Set("Cache-Control", "public, max-age=3600, stale-while-revalidate=86400")
 	writeJSON(w, 0, map[string]string{"html": buf.String(), "lang": lang})
 }
 

backend/internal/backend/handlers_notifications.go

@@ -3,8 +3,6 @@ package backend
 import (
 	"encoding/json"
 	"net/http"
-
-	"github.com/libnovel/backend/internal/storage"
 )
 
 // handleDismissNotification handles DELETE /api/notifications/{id}.
@@ -14,12 +12,11 @@ func (s *Server) handleDismissNotification(w http.ResponseWriter, r *http.Reques
 		jsonError(w, http.StatusBadRequest, "notification id required")
 		return
 	}
-	store, ok := s.deps.Producer.(*storage.Store)
-	if !ok {
-		jsonError(w, http.StatusInternalServerError, "storage not available")
+	if s.deps.NotificationStore == nil {
+		jsonError(w, http.StatusServiceUnavailable, "notification store not configured")
 		return
 	}
-	if err := store.DeleteNotification(r.Context(), id); err != nil {
+	if err := s.deps.NotificationStore.DeleteNotification(r.Context(), id); err != nil {
 		jsonError(w, http.StatusInternalServerError, "dismiss notification: "+err.Error())
 		return
 	}
@@ -33,12 +30,11 @@ func (s *Server) handleClearAllNotifications(w http.ResponseWriter, r *http.Requ
 		jsonError(w, http.StatusBadRequest, "user_id required")
 		return
 	}
-	store, ok := s.deps.Producer.(*storage.Store)
-	if !ok {
-		jsonError(w, http.StatusInternalServerError, "storage not available")
+	if s.deps.NotificationStore == nil {
+		jsonError(w, http.StatusServiceUnavailable, "notification store not configured")
 		return
 	}
-	if err := store.ClearAllNotifications(r.Context(), userID); err != nil {
+	if err := s.deps.NotificationStore.ClearAllNotifications(r.Context(), userID); err != nil {
 		jsonError(w, http.StatusInternalServerError, "clear notifications: "+err.Error())
 		return
 	}
@@ -52,12 +48,11 @@ func (s *Server) handleMarkAllNotificationsRead(w http.ResponseWriter, r *http.R
 		jsonError(w, http.StatusBadRequest, "user_id required")
 		return
 	}
-	store, ok := s.deps.Producer.(*storage.Store)
-	if !ok {
-		jsonError(w, http.StatusInternalServerError, "storage not available")
+	if s.deps.NotificationStore == nil {
+		jsonError(w, http.StatusServiceUnavailable, "notification store not configured")
 		return
 	}
-	if err := store.MarkAllNotificationsRead(r.Context(), userID); err != nil {
+	if err := s.deps.NotificationStore.MarkAllNotificationsRead(r.Context(), userID); err != nil {
 		jsonError(w, http.StatusInternalServerError, "mark all read: "+err.Error())
 		return
 	}
@@ -80,13 +75,12 @@ func (s *Server) handleListNotifications(w http.ResponseWriter, r *http.Request)
 		return
 	}
 
-	store, ok := s.deps.Producer.(*storage.Store)
-	if !ok {
-		jsonError(w, http.StatusInternalServerError, "storage not available")
+	if s.deps.NotificationStore == nil {
+		jsonError(w, http.StatusServiceUnavailable, "notification store not configured")
 		return
 	}
 
-	items, err := store.ListNotifications(r.Context(), userID, 50)
+	items, err := s.deps.NotificationStore.ListNotifications(r.Context(), userID, 50)
 	if err != nil {
 		jsonError(w, http.StatusInternalServerError, "list notifications: "+err.Error())
 		return
@@ -97,7 +91,7 @@ func (s *Server) handleListNotifications(w http.ResponseWriter, r *http.Request)
 	for _, item := range items {
 		b, _ := json.Marshal(item)
 		var n notification
-		json.Unmarshal(b, &n)
+		json.Unmarshal(b, &n) //nolint:errcheck
 		notifications = append(notifications, n)
 	}
 
@@ -111,16 +105,15 @@ func (s *Server) handleMarkNotificationRead(w http.ResponseWriter, r *http.Reque
 		return
 	}
 
-	store, ok := s.deps.Producer.(*storage.Store)
-	if !ok {
-		jsonError(w, http.StatusInternalServerError, "storage not available")
+	if s.deps.NotificationStore == nil {
+		jsonError(w, http.StatusServiceUnavailable, "notification store not configured")
 		return
 	}
 
-	if err := store.MarkNotificationRead(r.Context(), id); err != nil {
+	if err := s.deps.NotificationStore.MarkNotificationRead(r.Context(), id); err != nil {
 		jsonError(w, http.StatusInternalServerError, "mark read: "+err.Error())
 		return
 	}
 
 	writeJSON(w, 0, map[string]any{"success": true})
-}
+}

backend/internal/backend/handlers_textgen.go

@@ -313,6 +313,8 @@ func (s *Server) handleAdminTextGenChapterNames(w http.ResponseWriter, r *http.R
 	}
 
 	// Mark job as done in PB, persisting results so the Review button works.
+	// Use context.Background() — r.Context() may be cancelled if the SSE client
+	// disconnected before processing finished, which would silently drop results.
 	if jobID != "" && s.deps.AIJobStore != nil {
 		status := domain.TaskStatusDone
 		if jobCtx.Err() != nil {
@@ -321,7 +323,7 @@ func (s *Server) handleAdminTextGenChapterNames(w http.ResponseWriter, r *http.R
 		resultsJSON, _ := json.Marshal(allResults)
 		finalPayload := fmt.Sprintf(`{"pattern":%q,"slug":%q,"results":%s}`,
 			req.Pattern, req.Slug, string(resultsJSON))
-		_ = s.deps.AIJobStore.UpdateAIJob(r.Context(), jobID, map[string]any{
+		_ = s.deps.AIJobStore.UpdateAIJob(context.Background(), jobID, map[string]any{
 			"status":     string(status),
 			"items_done": chaptersDone,
 			"finished":   time.Now().Format(time.RFC3339),

backend/internal/backend/server.go

@@ -94,6 +94,10 @@ type Dependencies struct {
 	// BookAdminStore provides admin-only operations: archive, unarchive, hard-delete.
 	// If nil, the admin book management endpoints return 503.
 	BookAdminStore bookstore.BookAdminStore
+	// NotificationStore manages per-user in-app notifications.
+	// Always wired directly to *storage.Store (not the Asynq wrapper) so
+	// notification endpoints work regardless of whether Redis/Asynq is in use.
+	NotificationStore bookstore.NotificationStore
 	// Log is the structured logger.
 	Log *slog.Logger
 }

backend/internal/bookstore/bookstore.go

@@ -247,3 +247,14 @@ type ImportFileStore interface {
 	// GetImportChapters retrieves the pre-parsed chapters JSON.
 	GetImportChapters(ctx context.Context, key string) ([]byte, error)
 }
+
+// NotificationStore manages per-user in-app notifications.
+// Always wired directly to the concrete *storage.Store so it works
+// regardless of whether the Asynq task-queue wrapper is in use.
+type NotificationStore interface {
+	ListNotifications(ctx context.Context, userID string, limit int) ([]map[string]any, error)
+	MarkNotificationRead(ctx context.Context, id string) error
+	MarkAllNotificationsRead(ctx context.Context, userID string) error
+	DeleteNotification(ctx context.Context, id string) error
+	ClearAllNotifications(ctx context.Context, userID string) error
+}

backend/internal/storage/store.go

@@ -773,7 +773,7 @@ func (s *Store) CreateNotification(ctx context.Context, userID, title, message,
 
 // ListNotifications returns notifications for a user.
 func (s *Store) ListNotifications(ctx context.Context, userID string, limit int) ([]map[string]any, error) {
-	filter := fmt.Sprintf("user_id='%s'", userID)
+	filter := fmt.Sprintf(`user_id="%s"`, userID)
 	items, err := s.pb.listAll(ctx, "notifications", filter, "-created")
 	if err != nil {
 		return nil, err
@@ -805,7 +805,7 @@ func (s *Store) DeleteNotification(ctx context.Context, id string) error {
 
 // ClearAllNotifications deletes all notifications for a user.
 func (s *Store) ClearAllNotifications(ctx context.Context, userID string) error {
-	filter := fmt.Sprintf("user_id='%s'", userID)
+	filter := fmt.Sprintf(`user_id="%s"`, userID)
 	items, err := s.pb.listAll(ctx, "notifications", filter, "")
 	if err != nil {
 		return fmt.Errorf("ClearAllNotifications list: %w", err)
@@ -823,7 +823,7 @@ func (s *Store) ClearAllNotifications(ctx context.Context, userID string) error
 
 // MarkAllNotificationsRead marks all notifications for a user as read.
 func (s *Store) MarkAllNotificationsRead(ctx context.Context, userID string) error {
-	filter := fmt.Sprintf("user_id='%s'&&read=false", userID)
+	filter := fmt.Sprintf(`user_id="%s"&&read=false`, userID)
 	items, err := s.pb.listAll(ctx, "notifications", filter, "")
 	if err != nil {
 		return fmt.Errorf("MarkAllNotificationsRead list: %w", err)

ui/src/routes/admin/ai-jobs/+page.server.ts

@@ -6,8 +6,7 @@ export type { AIJob };
 
 export const load: PageServerLoad = async () => {
 	// Parent layout already guards admin role.
-	// Stream jobs so navigation is instant; list populates a moment later.
-	const jobs = listAIJobs().catch((e): AIJob[] => {
+	const jobs = await listAIJobs().catch((e): AIJob[] => {
 		log.warn('admin/ai-jobs', 'failed to load ai jobs', { err: String(e) });
 		return [];
 	});

ui/src/routes/admin/ai-jobs/+page.svelte

@@ -9,9 +9,9 @@
 
 	let jobs = $state<AIJob[]>([]);
 
-	// Resolve streamed promise on load and on server reloads (invalidateAll)
+	// data.jobs is a plain AIJob[] (resolved on server); re-sync on invalidateAll
 	$effect(() => {
-		data.jobs.then((resolved) => { jobs = resolved; });
+		jobs = data.jobs;
 	});
 
 	// ── Live-poll while any job is in-flight ─────────────────────────────────────

ui/src/routes/api/translation/[slug]/[n]/+server.ts

@@ -23,9 +23,12 @@ export const GET: RequestHandler = async ({ params, url }) => {
 		return new Response(null, { status: res.status });
 	}
 	const data = await res.json();
-	return new Response(JSON.stringify(data), {
-		headers: { 'Content-Type': 'application/json' }
-	});
+	const headers: Record<string, string> = { 'Content-Type': 'application/json' };
+	// Forward the immutable cache header from the backend so browsers and CDNs
+	// can cache translated chapter content without hitting MinIO on every load.
+	const cc = res.headers.get('Cache-Control');
+	if (cc) headers['Cache-Control'] = cc;
+	return new Response(JSON.stringify(data), { headers });
 };
 
 export const POST: RequestHandler = async ({ params, url, locals }) => {