Nova Stripe Checkout v2

WordPress plugin for Stripe Checkout subscriptions with per-seat pricing, three pricing tiers, and AU/NZ account routing.

Features

• ✅ Stripe Checkout integration for subscription payments
• ✅ Per-seat pricing with configurable quantity
• ✅ Three pricing tiers - Standard, Professional, and Ultimate
• ✅ Multi-country support - Route to Australian or New Zealand Stripe accounts
• ✅ Flexible billing - Quarterly or annual subscription periods
• ✅ Easy price management - Simple admin interface for price ID configuration
• ✅ Webhook handling - Automatic processing of Stripe events
• ✅ Secure - Input validation, webhook signature verification, no secret logging
• ✅ WordPress Coding Standards compliant
• ✅ PHPStan Level 7 static analysis
• ✅ Git Updater compatible

Requirements

• WordPress 6.0 or higher
• PHP 8.1 or higher
• Stripe account(s) for AU and/or NZ
• HTTPS enabled (required for Stripe)

Installation

Via Git Updater (Recommended)

1. Install Git Updater plugin
2. Add this repository URL to Git Updater
3. Install and activate the plugin

Manual Installation

1. Download the latest release
2. Upload to /wp-content/plugins/nova-checkout/
3. Run composer install --no-dev in the plugin directory
4. Activate the plugin through WordPress admin

Configuration

1. Stripe API Keys

Navigate to Settings → Nova Checkout and enter your Stripe API keys:

• Australia Secret Key - Your Stripe secret key for AU account
• New Zealand Secret Key - Your Stripe secret key for NZ account
• Australia Webhook Secret - Webhook signing secret for AU
• New Zealand Webhook Secret - Webhook signing secret for NZ

Alternative: Set via environment variables:

AU_STRIPE_SECRET_KEY=sk_live_...
NZ_STRIPE_SECRET_KEY=sk_live_...
AU_STRIPE_WEBHOOK_SECRET=whsec_...
NZ_STRIPE_WEBHOOK_SECRET=whsec_...

2. Price IDs

Navigate to Settings → Nova Prices and configure your Stripe price IDs for each tier:

Australia:

• Standard - Quarterly - Price ID for AU standard quarterly billing
• Standard - Annual - Price ID for AU standard annual billing
• Professional - Quarterly - Price ID for AU professional quarterly billing
• Professional - Annual - Price ID for AU professional annual billing
• Ultimate - Quarterly - Price ID for AU ultimate quarterly billing
• Ultimate - Annual - Price ID for AU ultimate annual billing

New Zealand:

• Standard - Quarterly - Price ID for NZ standard quarterly billing
• Standard - Annual - Price ID for NZ standard annual billing
• Professional - Quarterly - Price ID for NZ professional quarterly billing
• Professional - Annual - Price ID for NZ professional annual billing
• Ultimate - Quarterly - Price ID for NZ ultimate quarterly billing
• Ultimate - Annual - Price ID for NZ ultimate annual billing

Note: Create these prices in your Stripe dashboard first. You'll need 12 price IDs total (3 tiers × 2 periods × 2 countries).

3. Webhooks

Configure webhooks in your Stripe dashboard:

Australia Account:

• URL: https://yoursite.com/wp-json/nova/v1/stripe-webhook/au
• Events: checkout.session.completed, customer.subscription.*, invoice.payment_*

New Zealand Account:

• URL: https://yoursite.com/wp-json/nova/v1/stripe-webhook/nz
• Events: checkout.session.completed, customer.subscription.*, invoice.payment_*

Usage

Creating a Checkout Session

Make a POST request to /wp-json/nova/v1/checkout:

fetch('/wp-json/nova/v1/checkout', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    country: 'au',                    // 'au' or 'nz'
    tier: 'professional',             // 'standard', 'professional', or 'ultimate'
    billing_period: 'quarterly',      // 'quarterly' or 'annual'
    users: 5,                         // Number of seats
    success_url: 'https://example.com/success',
    cancel_url: 'https://example.com/cancel',
    customer_email: 'customer@example.com',  // Optional
    metadata: {                       // Optional
      source: 'website',
      campaign: 'spring2024'
    }
  })
})
.then(response => response.json())
.then(data => {
  if (data.success) {
    // Redirect to Stripe Checkout
    window.location.href = data.session_url;
  }
});

API Parameters

Parameter	Type	Required	Description
country	string	Yes	Country code: au or nz
tier	string	Yes	Pricing tier: standard, professional, or ultimate
billing_period	string	Yes	Billing period: quarterly or annual
users	integer	Yes	Number of seats/users (minimum: 1)
success_url	string	Yes	URL to redirect after successful checkout
cancel_url	string	Yes	URL to redirect if checkout is cancelled
customer_email	string	No	Pre-fill customer email address
metadata	object	No	Custom metadata to attach to the session

Response

Success:

{
  "success": true,
  "session_id": "cs_test_...",
  "session_url": "https://checkout.stripe.com/c/pay/cs_test_..."
}

Error:

{
  "code": "nova_checkout_error",
  "message": "Error message",
  "data": {
    "status": 400
  }
}

Example: Bricks Form Integration

Add this JavaScript to your Bricks form:

document.addEventListener('DOMContentLoaded', function() {
  const form = document.querySelector('#your-form-id');

  form.addEventListener('submit', async function(e) {
    e.preventDefault();

    const formData = new FormData(form);

    const response = await fetch('/wp-json/nova/v1/checkout', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({
        country: formData.get('country'),
        tier: formData.get('tier'),
        billing_period: formData.get('billing_period'),
        users: parseInt(formData.get('users')),
        success_url: window.location.origin + '/success',
        cancel_url: window.location.origin + '/cancel',
        customer_email: formData.get('email'),
      })
    });

    const data = await response.json();

    if (data.success) {
      window.location.href = data.session_url;
    } else {
      alert('Error: ' + data.message);
    }
  });
});

Webhook Events

The plugin fires WordPress actions for custom handling:

// Generic webhook event
add_action('nova_checkout_webhook_event', function($event, $country) {
  // Handle any webhook event
}, 10, 2);

// Specific events
add_action('nova_checkout_session_completed', function($session, $country) {
  // Checkout completed
}, 10, 2);

add_action('nova_checkout_subscription_created', function($subscription, $country) {
  // New subscription
}, 10, 2);

add_action('nova_checkout_subscription_updated', function($subscription, $country) {
  // Subscription updated
}, 10, 2);

add_action('nova_checkout_subscription_deleted', function($subscription, $country) {
  // Subscription cancelled
}, 10, 2);

add_action('nova_checkout_invoice_payment_succeeded', function($invoice, $country) {
  // Payment successful
}, 10, 2);

add_action('nova_checkout_invoice_payment_failed', function($invoice, $country) {
  // Payment failed
}, 10, 2);

Development

Setup

# Install dependencies
composer install

# Run all checks
composer test

# Individual checks
composer lint      # PHP syntax check
composer phpcs     # Coding standards
composer phpstan   # Static analysis
composer phpcpd    # Copy/paste detection
composer audit     # Security audit

Code Standards

• PHP 8.1+ with strict types
• WordPress Coding Standards
• PHPStan Level 7
• Comprehensive docblocks
• Early returns, explicit types
• No secrets in logs or errors

Security

• All inputs are sanitized and validated
• Webhook signatures are verified
• API keys never logged or exposed
• User-friendly error messages (no sensitive data)
• HTTPS required for production

Support

For issues, questions, or contributions, please use the GitHub repository.

License

GPL v2 or later

Credits

Built with:

• Stripe PHP SDK
• WordPress REST API
• Love and coffee ☕