Skip to content

Plugins

On this page

OpenCart Plugin

Install the official Paymos extension for OpenCart, connect the store without copying secrets, and validate payment status updates in test mode.

1. Requirements

  • OpenCart 4 and a public HTTPS Store URL
  • A Paymos account with a project selected in the dashboard
  • The official package from GitHub Releases

Official packages are identical for every merchant and contain no API keys, API secrets, project IDs, webhook secrets, OAuth tokens, or device codes.

2. Install

Upload the .ocmod.zip release with Extension Installer, install Paymos under Extensions → Payments, open its settings, and click Connect Paymos.

3. Connect

  1. Open the project you want to connect in the Paymos dashboard. The plugin uses that current project automatically; it never asks you to select it again.
  2. Click Connect Paymos in OpenCart.
  3. Approve the displayed store URL and current project in Paymos. There is no second project selector.
  4. Return to the CMS after the connected status appears.

For Sandbox and Live, Paymos reuses the merchant's single active Payment key or creates one when none exists. It reuses a webhook only when the exact callback URL, Invoice category, and current project match; otherwise it creates a dedicated Invoice webhook. A conflicting webhook at the same URL is never silently overwritten:

https://your-store.example/index.php?route=extension/paymos/payment/paymos.callback

OAuth device authorization is only the one-time delivery channel. The short-lived token is discarded; runtime Merchant API calls remain HMAC signed.

4. Secret storage

Credentials and temporary device state are stored in an AES-256-GCM encrypted OpenCart setting keyed from config_encryption. Saved secrets are not rendered back into the administration page.

5. Test and go live

Select Sandbox, place a test order, and confirm the invoice and webhook-driven status update. Switch the same installation to Live when ready; reconnect only after changing the store URL, revoking a Payment key, or rotating a webhook secret.

WHMCS Plugin Easy Digital Downloads Plugin