17.1. Overview
Payment systems are used by Kartris to accept payment (or in some cases, a promise of payment) through the store.
Kartris supports a number of different payment systems and has a flexible open plugin architecture that allows more to be added in future. There are four broad types:
- Remote – e.g. RBS Worldpay, SagePay VSP Form – these redirect customers to a secure page at the payment gateway's site, with the successful payment being communicated back to Kartris via some kind of 'callback'.
- Local – e.g. SagePay VSP Direct – the customer enters card details directly into Kartris and Kartris then communicates with the payment system server-to-server. Since card details are entered through Kartris itself, SSL is obligatory.
- Alternative Checkout – e.g. Google Checkout (now no longer available) – the customer is routed to the payment system's web at the start of the checkout and stays there for the entire process, with information such as pricing and shipping options, as well as payment success/failure communicated between the payment system and Kartris using server-to-server communication. Although the card details are not entered directly into Kartris, Google Checkout still requires that all communication between Kartris and the payment system be done under SSL.
- Special – this typically describes certain payment methods through Kartris that don't require a third party payment system. For example, payment by 'PO' (purchase order – to take an order where actual payment will be invoiced or made offline).
17.1.1. Payment Gateway - Common Settings
17.1.1.1. Status
This lets you switch the operation of the payment system as follows:
- ON – the payment system is active and is available for customers to select for payment
- OFF – the payment system is disabled
- TEST – the payment system is set in test mode; it will only be visible at checkout if you are logged in as a store admin. Orders will be passed with a 'test' flag so cards will not be billed.
- FAKE – an additional test setting; this simulates an order callback without sending anything to the payment gateway. It is a useful way to test the settings and see what happens with successful orders but without having to repeatedly go through the payment stage on the remote site.
17.1.1.2. Process currency
Most payment systems have a process currency. If you leave this blank, Kartris will pass orders to the payment system in whatever currency the user selects on your site. For that to work, your payment system provider must support multiple currencies, and your account with them must permit orders in all the currencies available on your site.
You should set the process currency from blank, if:
- Your payment system account only supports one currency
- Your store offers customers a choice of at least one currency that your payment system account does not support
- Your payment system provider provides very poor currency conversion rates, so you prefer to pass all orders in a single currency as customers will get better conversion rates from their credit card providers.
The process currency (if not blank) should be a three-letter ISO code for the appropriate currency.
Customers will be alerted at the last step of the checkout that the actual amount they will pay will be converted, and they will be shown the converted amount in that currency, as well as the order total in their preferred currency. This conversion will be done at the rate in your currency settings.
17.1.1.3. Encrypting the settings file
17.1.2. Installing Further Payment Systems
Unzip the files and copy the folder for the payment system to the 'Plugins' folder in the Kartris web. Then go to 'Configuration > Payment and Shipping Gateways'.
Click the 'Refresh' link and Kartris should find the new payment system. Once in the list, you can click 'Edit' to change its settings. Each payment system has its own settings, which vary from system to system. This information is not stored in the database; instead it is stored as XML within the payment system itself. This makes installation simpler since you don't need to add new database records for each new payment system.
If you receive an error when you try to save changes to the settings of a payment system, it is most likely caused by there not being 'write' permission to the 'Plugins' folder. You will need to adjust this from the 'properties' dialog in Windows Explorer, or (if on shared hosting) contact your host's technical support team.