Checkout Integration

The most common way to integrate Gale. Create a checkout session via API, redirect your customer to Gale’s hosted page, and we handle the rest—including card collection, eligibility detection, and LMN flow for dual-purpose products.

How It Works

Customer clicks “Checkout” on your site
Your site creates a checkout session via POST /api/v2/checkout
Gale returns a checkout_url
Your site redirects customer to the checkout URL
Customer completes payment on Gale’s hosted page
Gale sends webhook with order.created event
Your system fulfills the order
Customer is redirected back to your success_url

When to Use Checkout

Using Shopify or WooCommerce? Install our plugin instead:

The Checkout API is for custom platforms and sites not supported by our plugins.

Perfect for:

Custom e-commerce platforms
Membership and subscription platforms
SaaS applications
Next.js, React, or custom-built sites
Adding HSA/FSA payments alongside existing payment methods

Use cases:

Next.js membership site with monthly subscriptions
Custom healthcare e-commerce store
Wellness platform built on custom stack
Telehealth service with custom checkout

Quick Start

1. Create Checkout Session

const createCheckout = async (cart) => {
  const response = await fetch('https://api.withgale.com/api/v2/checkout', {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${process.env.GALE_API_KEY}`,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({
      reference_id: cart.id,
      customer: {
        email: cart.customerEmail,
        first_name: cart.firstName,
        last_name: cart.lastName
      },
      line_items: cart.items.map(item => ({
        product_id: item.sku,
        name: item.name,
        quantity: item.quantity,
        price: item.price,
        currency: 'USD'
      })),
      shipping_info: cart.shippingAddress,
      shipping: cart.shipping,
      tax: cart.tax,
      success_url: 'https://yoursite.com/order/success',
      failure_url: 'https://yoursite.com/cart'
    })
  });

  const checkout = await response.json();
  return checkout.checkout_url;
};

2. Redirect Customer

// Redirect to Gale's hosted checkout
const checkoutUrl = await createCheckout(cart);
window.location.href = checkoutUrl;

3. Handle Webhook

app.post('/webhooks/gale', async (req, res) => {
  const event = req.body;

  if (event.type === 'order.created') {
    const order = event.data;

    // Fulfill the order
    await fulfillOrder(order.id, {
      items: order.line_items,
      shipping: order.customer.shipping_address
    });

    // Send confirmation email
    await sendEmail({
      to: order.customer.email,
      subject: `Order ${order.order_number} Confirmed`,
      template: 'order_confirmation'
    });
  }

  res.status(200).send('OK');
});

Integration Examples

Next.js Membership Site

// app/checkout/route.ts
import { NextResponse } from 'next/server';

export async function POST(request: Request) {
  const { tier, customerId } = await request.json();

  const membershipPlans = {
    basic: { productId: 'BASIC-001', price: 2900 },
    premium: { productId: 'PREMIUM-001', price: 4900 },
    elite: { productId: 'ELITE-001', price: 9900 }
  };

  const plan = membershipPlans[tier];

  const response = await fetch('https://api.withgale.com/api/v2/checkout', {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${process.env.GALE_API_KEY}`,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({
      customer: await getCustomer(customerId),
      line_items: [{
        product_id: plan.productId,
        name: `${tier} Membership`,
        quantity: 1,
        price: plan.price,
        currency: 'USD'
      }],
      payment_type: 'subscription',
      subscription: {
        interval: 'monthly'
      },
      success_url: `${process.env.BASE_URL}/welcome?tier=${tier}`,
      failure_url: `${process.env.BASE_URL}/pricing`
    })
  });

  const checkout = await response.json();
  return NextResponse.json({ url: checkout.checkout_url });
}

React E-commerce Checkout

function CheckoutButton({ cart }) {
  const handleCheckout = async () => {
    const response = await fetch('/api/create-checkout', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ cart })
    });

    const { checkout_url } = await response.json();
    window.location.href = checkout_url;
  };

  return (
    <button onClick={handleCheckout} className="checkout-btn">
      Pay with HSA/FSA
    </button>
  );
}

Shopify Integration

// Add Gale as payment option
const addGalePaymentMethod = () => {
  // In checkout page
  const galeButton = document.createElement('button');
  galeButton.textContent = 'Pay with HSA/FSA';
  galeButton.onclick = async () => {
    const cart = await fetch('/cart.js').then(r => r.json());

    const checkout = await createGaleCheckout({
      customer: {
        email: cart.customer.email,
        first_name: cart.customer.first_name,
        last_name: cart.customer.last_name
      },
      line_items: cart.items.map(item => ({
        product_id: item.sku,
        name: item.title,
        quantity: item.quantity,
        price: item.price,
        currency: 'USD'
      })),
      success_url: window.location.origin + '/thank-you',
      failure_url: window.location.origin + '/cart'
    });

    window.location.href = checkout.checkout_url;
  };

  document.querySelector('.payment-methods').appendChild(galeButton);
};

What Gale Handles

When customers reach the hosted checkout page, Gale automatically:

Collects payment information - Secure card entry
Detects HSA/FSA eligibility - Real-time SIGIS verification
Handles dual-purpose items - LMN flow when required
Processes payment - Charges appropriate payment method(s)
Creates order - Sends webhook notification to your system

Checkout URL Customization

Pre-fill customer information to streamline checkout:

{
  customer: {
    email: "customer@example.com",
    first_name: "Jane",
    last_name: "Doe",
    phone: "+1-555-123-4567"
  },
  shipping_info: {
    address_line_1: "123 Main St",
    city: "New York",
    state: "NY",
    postal_code: "10001",
    country: "US"
  }
}

Customer only needs to enter payment details.

Subscription Support

For recurring payments, add subscription parameters:

{
  payment_type: "subscription",
  subscription: {
    interval: "monthly",
    interval_count: 1,
    trial_period_days: 14
  }
}

Testing

Use test API keys and test cards:

// Test card numbers
const testCards = {
  success: '4111111111111111',
  decline: '4000000000000002',
  requiresAuth: '4000002500003155'
};

See Test Cards for full list.

Support

Questions about checkout integration?

📧 Email: support@withgale.com
💬 Contact Support

Getting Started

Integration Guides

Core Objects

Checkout

Payment Links

Orders

Products

Subscriptions

Webhooks & Errors

Checkout (Hosted Page)

Checkout Integration

How It Works

When to Use Checkout

Quick Start

1. Create Checkout Session

2. Redirect Customer

3. Handle Webhook

Integration Examples

Next.js Membership Site

React E-commerce Checkout

Shopify Integration

What Gale Handles

Checkout URL Customization

Subscription Support

Testing

Support

​Checkout Integration

​How It Works

​When to Use Checkout

​Quick Start

​1. Create Checkout Session

​2. Redirect Customer

​3. Handle Webhook

​Integration Examples

​Next.js Membership Site

​React E-commerce Checkout

​Shopify Integration

​What Gale Handles

​Checkout URL Customization

​Subscription Support

​Testing

​Related Resources

​Support

Checkout Integration

How It Works

When to Use Checkout

Quick Start

1. Create Checkout Session

2. Redirect Customer

3. Handle Webhook

Integration Examples

Next.js Membership Site

React E-commerce Checkout

Shopify Integration

What Gale Handles

Checkout URL Customization

Subscription Support

Testing

Related Resources

Support