@drewsepsi/billing-sdk

TypeScript SDK for adding subscriptions and usage billing to your Next.js app. Integrate with Stripe in minutes, not days.

Quick Start

npm install @drewsepsi/billing-sdk

import { BillingSDK } from "@drewsepsi/billing-sdk";

const billing = new BillingSDK({
  baseUrl: process.env.NEXT_PUBLIC_API_URL,
});

// Create a checkout session
const url = await billing.createCheckout({
  priceId: "price_pro",
  userId: "user_123",
});

// Redirect user to Stripe
window.location.href = url;

Features

⚡ One-line checkout - Create Stripe checkout sessions instantly
📊 Usage tracking - Built-in metering for usage-based billing
🔐 License validation - Verify SDK licenses with tier-based features
🎨 React hooks - Ready-to-use useSubscription, useBilling hooks
🧪 Sandbox mode - Test billing flows without real charges
📝 TypeScript - Full type safety out of the box

Installation

npm install @drewsepsi/billing-sdk
# or
yarn add @drewsepsi/billing-sdk
# or
pnpm add @drewsepsi/billing-sdk

Basic Usage

1. Initialize the SDK

import { BillingSDK } from "@drewsepsi/billing-sdk";

const billing = new BillingSDK({
  baseUrl: process.env.NEXT_PUBLIC_API_URL || "http://localhost:3000",
  license: {
    licenseKey: process.env.DREW_BILLING_LICENSE_KEY, // Optional: for SDK features
  },
});

2. Create a Checkout

const checkout = await billing.createCheckout({
  priceId: "price_pro_monthly",
  userId: "user_123",
  successUrl: "/dashboard?success=true",
  cancelUrl: "/pricing?canceled=true",
});

// Redirect to Stripe
window.location.href = checkout.url;

3. Check Subscription Status

const subscription = await billing.getSubscription("user_123");

if (subscription.status === "active") {
  // Grant premium access
}

4. Track Usage

// Record an API call or feature usage
await billing.trackUsage({
  userId: "user_123",
  event: "api_call",
  quantity: 1,
});

// Check remaining quota
const usage = await billing.getUsage("user_123");
console.log(`Used ${usage.current} of ${usage.limit}`);

React Integration

Provider Setup

import { BillingProvider } from "@drewsepsi/billing-sdk/react";

function App() {
  return (
    <BillingProvider
      config={{
        baseUrl: process.env.NEXT_PUBLIC_API_URL,
      }}
    >
      <YourApp />
    </BillingProvider>
  );
}

Use Subscription Hook

import { useSubscription } from "@drewsepsi/billing-sdk/react";

function Dashboard() {
  const { subscription, isLoading, isActive } = useSubscription("user_123");

  if (isLoading) return <Spinner />;

  return (
    <div>
      <h1>Dashboard</h1>
      {isActive ? (
        <PremiumFeatures />
      ) : (
        <UpgradePrompt />
      )}
    </div>
  );
}

Server-Side Usage

For API routes and server components:

import { BillingSDK } from "@drewsepsi/billing-sdk/server";

// Server-side SDK (no React dependencies)
const billing = new BillingSDK({
  baseUrl: process.env.API_URL,
  apiKey: process.env.BILLING_API_KEY,
});

// Validate a license key
const license = await billing.validateLicense("license_key_here");

if (license.valid && license.tier === "pro") {
  // Grant pro features
}

Sandbox Mode

Test your billing integration without real charges:

import { createSandboxBilling } from "@drewsepsi/billing-sdk/sandbox";

const billing = createSandboxBilling({
  baseUrl: "http://localhost:3000",
});

// All operations work without hitting Stripe
const checkout = await billing.createCheckout({
  priceId: "test_price",
  userId: "test_user",
});

License Validation (SDK Customers)

If you've purchased a Drew Billing SDK license, validate it to unlock features:

const billing = new BillingSDK({
  baseUrl: "https://your-app.com",
  license: {
    licenseKey: process.env.DREW_BILLING_LICENSE_KEY,
  },
});

// The SDK automatically validates on initialization
// and enables features based on your tier (Pro/Team/Enterprise)

API Reference

`BillingSDK`

Main SDK class for billing operations.

Method	Description
`createCheckout(options)`	Create a Stripe checkout session
`getSubscription(userId)`	Get user's subscription status
`getUsage(userId)`	Get usage statistics
`trackUsage(event)`	Track a usage event
`validateLicense(key)`	Validate a license key
`createCustomerPortal(userId)`	Create customer portal session

React Hooks

Hook	Description
`useSubscription(userId)`	Get subscription state
`useBilling()`	Access SDK instance
`useUsage(userId)`	Track and display usage

Environment Variables

# Required
NEXT_PUBLIC_API_URL=https://your-app.com

# Optional (for SDK license validation)
DREW_BILLING_LICENSE_KEY=your-license-key-here

# Optional (for server-side)
BILLING_API_KEY=your-api-key

Examples

SaaS Starter

npx @drewsepsi/billing-cli init --template saas

API Product with Usage

npx @drewsepsi/billing-cli init --template api

AI Credits System

npx @drewsepsi/billing-cli init --template ai-credits

Documentation

License

MIT © Drew

Built with ❤️ by Drew Billing