Spree Payments

Before writing code

Fetch live docs:

1. Fetch https://spreecommerce.org/docs/developer/core-concepts/payments for the Payment + PaymentSession model.
2. Fetch the integration repo README — https://github.com/spree/spree_stripe / spree_adyen / spree_paypal_checkout — for current install + config.
3. Check the gateway's own SDK docs (Stripe / Adyen / PayPal) for the latest API version.
4. Inspect the live Spree::Payment source for state transitions and column names.
5. Check the v5.4 announcement for the PaymentSession introduction.

Conceptual Architecture

PaymentMethod, Payment, PaymentSession

Payment State Machine

checkout → processing → pending → completed
                    ↓
                  failed | void | invalid

• checkout — initialized, waiting for capture
• processing — sent to gateway
• pending — gateway accepted, awaiting async confirmation (3DS, ACH)
• completed — captured
• failed — declined
• void — voided pre-capture
• invalid — gateway returned an unparseable response

Payment Sources

Most Payment rows have a polymorphic source:

• Spree::CreditCard — tokenized card data
• Spree::StoreCredit — user's store credit balance
• Spree::GiftCard — gift card balance
• Gateway-specific (Spree::PayPalCheckout::Order, etc.)

The v5.4 PaymentSession Flow

1. Storefront calls POST /api/v3/store/checkout/payment_sessions with payment_method_id.
2. Spree creates a PaymentSession, hits the gateway's session API (Stripe Payment Intent, Adyen /sessions, PayPal /v2/orders).
3. Storefront renders the gateway's hosted UI (Stripe Elements, Adyen Drop-in, PayPal Buttons) with the returned client secret / session data.
4. User authorizes (handles 3DS, SCA, Apple/Google Pay).
5. Storefront calls POST /api/v3/store/checkout/complete.
6. Spree captures the session into a Payment and advances the order.

Provider differences are hidden behind the PaymentSession envelope — the storefront code is gateway-agnostic above the UI layer.

Stripe via spree_stripe

• One-click installer in admin (Settings → Payment Methods → Stripe → Connect)
• Supports cards, Apple Pay, Google Pay, Link, Klarna, Affirm, SEPA
• Stripe Connect for marketplace payouts (Enterprise marketplace)
• Webhooks: payment_intent.succeeded, payment_intent.payment_failed, etc. routed to /webhooks/stripe

Adyen via spree_adyen

• Supports cards + many local payment methods
• Drop-in UI in the Next.js storefront
• HMAC-signed webhooks

PayPal via spree_paypal_checkout

• PayPal Checkout (Smart Buttons) + PayPal Credit
• Server-side order creation

Refunds

Refund a captured Payment:

refund = Spree::Refund.create!(
  payment: payment,
  amount: payment.amount,
  reason: Spree::RefundReason.first
)
refund.perform!

perform! hits the gateway's refund endpoint and updates the Payment#state if fully refunded.

Reimbursement vs Refund

• Refund — credits back the original payment method.
• Reimbursement — orchestrates the return flow; can issue a Refund OR a StoreCredit, on a CustomerReturn.

StoreCredit and GiftCard as Payment Methods

Both work as native payment sources. The checkout state machine skips the payment step if store credit fully covers the order.

Implementation Guidance

Adding Stripe to a Spree v5.4+ Project

# Gemfile
gem 'spree_stripe'

# Then
bundle install
bin/rails g spree_stripe:install
bin/rails db:migrate

In admin → Settings → Payment Methods → Stripe → connect via OAuth (Stripe Express / Standard). Set webhook endpoint in Stripe dashboard to https://yourdomain/webhooks/stripe. Verify the env vars (STRIPE_API_KEY, STRIPE_PUBLISHABLE_KEY, STRIPE_WEBHOOK_SECRET) — check the README for the current naming.

Creating a PaymentSession (v5.4+ headless)

// In a Server Action of the Next.js storefront
const session = await spree.checkout.createPaymentSession({
  paymentMethodId: 'pm_stripe',
});
// session.clientSecret used by Stripe Elements
// session.dropInPayload used by Adyen Drop-in

(Verify against @spree/sdk docs.)

Authoring a Custom Gateway

# app/models/my_app/payment_method/custom_gateway.rb
class MyApp::PaymentMethod::CustomGateway < Spree::PaymentMethod
  def payment_source_class
    Spree::CreditCard
  end

  def gateway_class
    MyApp::Gateways::CustomBilling
  end

  def supports?(source)
    source.is_a?(Spree::CreditCard)
  end

  def actions
    %w[capture void credit]
  end
end

# app/models/my_app/gateways/custom_billing.rb
class MyApp::Gateways::CustomBilling
  def initialize(options = {})
    @api_key = options[:api_key]
  end

  def authorize(amount_cents, source, options = {})
    # Hit the gateway's authorize endpoint
    # Return ActiveMerchant::Billing::Response.new(...)
  end

  def capture(amount_cents, authorization_token, options = {})
    # …
  end

  def void(authorization_token, options = {})
    # …
  end

  def credit(amount_cents, authorization_token, options = {})
    # refund
  end
end

Register the payment method type in an initializer:

Rails.application.config.spree.payment_methods << MyApp::PaymentMethod::CustomGateway

Webhook Handling

Spree gateway gems mount their own webhook routes (e.g., /webhooks/stripe). When customizing:

# Subscribe to Spree's own events after webhook processing
class PaymentSubscriber < Spree::Subscriber
  subscribes_to 'payment.paid'
  on 'payment.paid', :sync_to_accounting
end

Handling 3DS / SCA

Payment#state == 'pending' after authorize means the gateway is waiting for the customer to complete a challenge. The storefront polls or listens for the gateway's webhook, then either payment.complete! or payment.failure!.

Split Tender (StoreCredit + Card)

Spree natively supports multiple Payment rows per order. The order updater allocates outstanding balance across them in order of creation. The order state machine completes only when sum(payments.completed) == order.total.

Common Pitfalls

• Hardcoding gateway secrets in config/spree.rb — use Rails credentials or env vars.
• Manually setting Payment#state = 'completed' — bypasses the gateway flow; reconciliation breaks.
• Refunding more than the original Payment amount — gateway rejects; pre-validate.
• Forgetting webhook signature verification — gateway gems handle this, but custom integrations must verify HMAC.
• PaymentSession not cleaned up on cart abandonment — gateways have their own expiry; don't rely on Spree to release holds.
• Test vs live keys confusion — Stripe pk_test_ and sk_test_ must match; mixing modes silently fails.
• Wrong payment_method per store — multi-store deployments need a PaymentMethod per store unless you explicitly mark it shared.

Always re-fetch the gateway gem's README before writing integration code — gateway APIs and Spree wrapper versions drift independently.