bok

A React component library for reading EPUB files. Built with React, TypeScript, and Vite.

The reader that is spawned will render a column view, with each column representing a page of the book. The user is able to change the font size, font family, line spacing, top padding, side margin and toggle the reader in fullscreen.

Butt.

Installation

npm install bok
# or
yarn add bok

Usage

import React from "react";
import { BokReader } from "bok-reader";

function MyBookViewer() {
    const epubUrl = "https://www.path.com/to/your/book.epub"; // Can be a URL, File object, or ArrayBuffer

    return (
        <div style={{
            height: "100vh",
            width: "100vw",
        }}>
            <BokReader epubDataSource={epubUrl} />
        </div>
    );
}

export default MyBookViewer;

Props to BokReader

• epubDataSource: File | ArrayBuffer | string | null - The source of the EPUB file (File object, ArrayBuffer, or URL string).
• onTitleChange?: (title: string) => void - Callback when the book title is loaded.
• onLoadingChange?: (isLoading: boolean) => void - Callback when the loading state changes.
• onError?: (errorMsg: string) => void - Callback when an error occurs during loading or processing.
• onSyncEvent?: (event: BokReaderSyncEvent) => void - Emits semantic local mutations for sync queues (progress.set, highlight.add, highlight.remove, highlight.updateColor).
• syncState?: BokReaderSyncState | null - Host-provided remote/hydrated state for the current bookId.
• onConflictDetected?: (conflict: BokReaderSyncConflict) => void - Called when incoming syncState conflicts with non-empty local data and forceApply is not set.
• supportedFonts?: { displayName: string; name: string }[] - Array of custom fonts to make available in the options menu.
• defaultFontFamily?: string - Default reader font family used only when bok_global_font_family is not already set in localStorage (falls back to "Courier New").
• color?: string - Hexadecimal value. Color tint of the component.
• style?: React.CSSProperties - Optional inline styles for the main wrapper component.

Imperative Sync API (ref)

BokReader exposes a ref handle:

• getSyncSnapshot(): BokReaderSyncSnapshot | null
• applySyncState(syncState: BokReaderSyncState, options?: { forceApply?: boolean }): boolean (true means accepted: applied now or queued until reader is ready)
• getPendingSyncEvents(): BokReaderSyncEvent[]
• acknowledgeSyncEvents(mutationIds: string | string[]): void

Development Scripts

• npm run dev: Start development server.
• npm run build: Build the library for production.
• npm run lint: Lint the project files.
• npm run preview: Preview the production build locally.

Dependencies

• jszip

Peer Dependencies

• react >=18.3.1
• react-dom >=18.3.1