bkper-js library is a simple and secure way to access the Bkper REST API on Node.js and modern browsers.

It provides a set of classes and functions to interact with the Bkper API, including authentication, authorization, and data manipulation.

Documentation

• Developer Docs
• API Reference

Installation

Add the package:

npm i -S bkper-js

bun add bkper-js

pnpm add bkper-js

yarn add bkper-js

Usage

CDN / Browser

The simplest way to use bkper-js in a browser — no build tools, no npm, just a <script> tag and a valid access token. Works on any domain.

<script src="https://cdn.jsdelivr.net/npm/bkper-js@2/dist/bkper.min.js"></script>
<script>
    const { Bkper } = bkperjs;

    async function listBooks(token) {
        Bkper.setConfig({
            oauthTokenProvider: async () => token,
        });
        const bkper = new Bkper();
        return await bkper.getBooks();
    }

    // Example: prompt for a token and list books
    document.addEventListener('DOMContentLoaded', () => {
        document.getElementById('go').addEventListener('click', async () => {
            const token = document.getElementById('token').value;
            const books = await listBooks(token);
            document.getElementById('output').textContent = books.map(b => b.getName()).join('\n');
        });
    });
</script>

<input id="token" placeholder="Paste your access token" />
<button id="go">List Books</button>
<pre id="output"></pre>

Get an access token with the Bkper CLI:

bkper auth login   # one-time setup
bkper auth token   # prints a token (valid for 1 hour)

Pin to a specific version by replacing @2 with e.g. @2.31.0.

Node.js / CLI Scripts

For local scripts and CLI tools, use the bkper CLI package for authentication:

import { Bkper } from 'bkper-js';
import { getOAuthToken } from 'bkper';

// Configure with CLI authentication
Bkper.setConfig({
    oauthTokenProvider: async () => getOAuthToken(),
});

// Create Bkper instance
const bkper = new Bkper();

// Get a book and work with it
const book = await bkper.getBook('your-book-id');
console.log(`Book: ${book.getName()}`);

// List all books
const books = await bkper.getBooks();
console.log(`You have ${books.length} books`);

First, login via CLI: bkper auth login

npm + Bundler

If you are using a bundler (Vite, webpack, esbuild, etc.), install from npm and provide an access token the same way as the CDN example:

import { Bkper } from 'bkper-js';

Bkper.setConfig({
    oauthTokenProvider: async () => 'your-access-token',
});

const bkper = new Bkper();
const books = await bkper.getBooks();

Web Applications on *.bkper.app

Note: @bkper/web-auth only works on *.bkper.app subdomains. Its session cookies are scoped to the .bkper.app domain and will not work on any other domain. For apps on other domains, use the CDN / Browser approach with an access token instead.

For apps hosted on *.bkper.app subdomains, use the @bkper/web-auth SDK for built-in OAuth login flow:

import { Bkper } from 'bkper-js';
import { BkperAuth } from '@bkper/web-auth';

// Initialize authentication
const auth = new BkperAuth({
    onLoginSuccess: () => initializeApp(),
    onLoginRequired: () => showLoginButton(),
});

// Restore session on app load
await auth.init();

// Configure Bkper with web auth
Bkper.setConfig({
    oauthTokenProvider: async () => auth.getAccessToken(),
});

// Create Bkper instance and use it
const bkper = new Bkper();
const books = await bkper.getBooks();

See the @bkper/web-auth documentation for more details.

API Key (Optional)

API keys are optional and only needed for dedicated quota limits. If not provided, requests use a shared managed quota via the Bkper API proxy.

Bkper.setConfig({
    oauthTokenProvider: async () => getOAuthToken(),
    apiKeyProvider: async () => process.env.BKPER_API_KEY, // Optional - for dedicated quota
});