Invoice payment choices and method discovery

Source version and installed-release boundary

This manual covers the reviewed newer product source workflow. It requires its matching released core, additive database structure and signed modules where applicable. The separately approved licensed 1.3.8 archive can have an earlier workflow. Do not assume these screens or commands exist merely from a numeric version label, and do not copy newer source files over a signed installation. Documentation publication does not upgrade the product or enable any external account.

Storefront checkout opens the issued invoice directly after placing the order and clearing the cart. A success message confirms the order and directs the payer to payment choices. Paid or zero-charge invoices confirm that no payment is due. Existing order placement, ownership, review and idempotency checks remain in force.

Payable customer invoices show visible grouped choices for online payments and bank transfers. Every eligible gateway and bank remains named before selection. Selecting a bank shows its account holder, transfer instructions and private payment-slip form. A submitted reference opens the existing billing verification ticket; submission alone never settles the invoice or activates a service. Payment activity remains separate from settled payments. Without JavaScript, the choices link to their usable method panels on the same page.

Eligibility follows the stored invoice's seller, storefront, legal country and currency. Disabled, incomplete or unrelated offline methods are not substituted. Existing pending gateway attempts and offline submissions retain their payment-exclusion controls. Invoice viewers, including an authorised staff customer preview, can read public method labels; payment submissions and hosted checkout retain their separate payer permissions and impersonation restrictions.

Online gateways may implement the optional PaymentMethodDiscovery contract. Initial invoice HTML uses cached provider-confirmed previews without provider I/O. An authenticated read-only invoice endpoint refreshes them asynchronously. Airwallex returns active account methods for the invoice currency and customer billing country, with card networks when supplied. Visa, Mastercard, American Express, wallets and buy now pay later methods are shown only when returned for that account and invoice context. Wallets and buy now pay later methods remain conditional on device, country and checkout eligibility; the secure checkout determines final availability.

Preview and hosted checkout use the same shopper country from the frozen invoice customer snapshot, with the profile used only for legacy invoices without a country. The seller's country, current website and currency do not substitute for shopper location. Unknown or malformed shopper country is omitted.

Discovery does not start checkout, reserve a payment or change an invoice. Successes are cached for fifteen minutes and failures for one minute, separated by connection, configuration, module version, currency and country. Provider work has a bounded time budget. A failure leaves the payment button usable and directs the customer to the methods shown at secure checkout. Provider bodies, credentials and raw diagnostics are excluded from the customer response. Omitting the connection identifier returns cached previews without provider requests.

Validation uses synthetic in-memory records and intercepted browser requests. The invoice payment suites cover method selection, bank details, receipt controls, permissions, unresolved payment guards, provider discovery, caching, escaping and failure fallback. No merchant bank details or live business configuration belong in product source.