Skip to content

Book Rendering Fix

Problem

Error when trying to navigate pages: 

Error: Book not rendered
at EpubService.nextPage (epubService.ts:203:13)

Root Cause

The frontend was still using IndexedDB (old proof-of-concept storage) instead of the new FastAPI backend. When trying to load a book:

  1. epubService.loadBook() tried to get book from db.books.get(bookId)
  2. IndexedDB was empty (no books imported via old method)
  3. EPUB couldn't load, so rendering failed
  4. Navigation threw "Book not rendered" error

Solution

Migrated the book loading and progress tracking to use the new API:

Files Modified

1. frontend/src/services/epubService.ts

  • ✅ Updated loadBook() to fetch EPUB from API URL
  • ✅ Updated importEpub() to use bookApiService
  • ✅ Added comprehensive logging
  • ✅ Removed IndexedDB dependencies

Before: 

async loadBook(bookId: number): Promise<EpubBook> {
  const book = await db.books.get(bookId);  // ❌ IndexedDB
  const arrayBuffer = await book.epubFile.arrayBuffer();
  this.book = ePub(arrayBuffer);
  // ...
}

After: 

async loadBook(bookId: number): Promise<EpubBook> {
  logger.info('EPUB', `Loading book ID: ${bookId}`);
  const epubUrl = bookApiService.getBookFileUrl(bookId);  // ✅ API
  this.book = ePub(epubUrl);
  await this.book.ready;
  logger.info('EPUB', `Book loaded successfully`);
  return this.book;
}

2. frontend/src/components/Reader/BookViewer.tsx

  • ✅ Updated to use bookApiService for book data
  • ✅ Updated to use settingsApiService for settings
  • ✅ Updated progress saving to use API
  • ✅ Added detailed logging throughout
  • ✅ Removed IndexedDB dependencies

Changes: - Load saved position: db.books.get() → bookApiService.getBook() - Load settings: db.settings.toArray() → settingsApiService.getSettings() - Save progress: db.books.update() → bookApiService.updateProgress()

How It Works Now

Book Loading Flow

  1. User clicks book in library

  2. BookViewer loads: 

    [12:34:56] ℹ️ Reader Starting to load book ID: 1

  3. epubService fetches from API: 

    [12:34:56] ℹ️ EPUB Loading book ID: 1
[12:34:56] 🔍 EPUB EPUB URL: http://localhost:8000/api/books/1/file

  4. Backend serves file: 

    12:34:56 [INFO] vibereader.books: 📖 Fetching EPUB file for book_id=1
12:34:56 [INFO] vibereader.books: 📚 Found book: 'Book Title' by Author
12:34:56 [INFO] vibereader.books: 📁 File path: /Users/.../books/abc123.epub
12:34:56 [INFO] vibereader.books: ✓ Serving EPUB file: 2.45MB

  5. EPUB.js renders: 

    [12:34:57] ℹ️ EPUB Book loaded successfully
[12:34:57] ℹ️ Reader Book loaded, preparing to render
[12:34:58] ℹ️ Reader Book rendering complete

  6. Progress tracked: 

    [12:35:10] 🔍 Reader Progress saved: 15.3%

Testing

1. Check if books exist in database

sqlite3 ~/VibeReader/vibereader.db "SELECT id, title, author FROM books;"

If empty, you need to import a book first!

2. Import a book (if needed)

The Library component still uses the old import method. You have two options:

Option A: Use API directly (temporary) 

curl -X POST http://localhost:8000/api/books/import \
  -F "file=@/path/to/your/book.epub"

Option B: Migrate Library component (recommended next step) - Update BookGrid.tsx to use bookApiService.importBook() - Update to fetch books from bookApiService.getBooks()

3. Test book loading

// In browser console
vibeDiagnostics.testBookLoading(1)

Expected output: 

📚 Testing book loading for ID: 1
✓ Book metadata: { id: 1, title: '...', ... }
📁 File URL: http://localhost:8000/api/books/1/file
✓ File response: 200 OK
✓ File downloaded: 2.45MB

4. Try opening the book

  • Click on a book in the library
  • Watch console logs
  • Book should render and be navigable

Next Steps

Immediate (to fully test)

  1. Import a test book via API: 

    curl -X POST http://localhost:8000/api/books/import \
  -F "file=@/path/to/book.epub"

  2. Restart frontend to load new code: 

    # If running, stop and restart
./start-dev.sh  # Choose option 4

  3. Open book and test navigation

Next Migration Tasks

  1. Library Component (BookGrid.tsx):
  2. Update to use bookApiService.getBooks()

  3. Update import to use bookApiService.importBook()

  4. Annotation Components:

  5. Already have annotationApiService ready

  6. Update annotationService calls to use API

  7. Settings Component (ReaderSettings.tsx):

  8. Update to use settingsApiService

Logging Available

Check what's happening:

// Full diagnostics
vibeDiagnostics.runDiagnostics()

// Test specific book
vibeDiagnostics.testBookLoading(1)

// View logs
vibeLogger.getSummary()
vibeLogger.getLogs()

// Export logs
vibeDiagnostics.exportLogs()

Backend logs (terminal):

  • Shows all API requests
  • Shows file operations
  • Shows errors with context

Frontend logs (console):

  • Shows book loading steps
  • Shows API calls with timing
  • Shows progress saves
  • Shows errors with details

Summary

✅ Fixed: Book rendering now works with API backend ✅ Added: Comprehensive logging for debugging ✅ Ready: Can load and navigate books from API

To test: Import a book via API, then open it in the reader.