After 2checkout was acquired, they revamped the interface and created a whole new API. The new docs can be found here https://knowledgecenter.2checkout.com/Integration/Start_using_the_2Checkout_API.

The migration is apparently quite old. See the announcement here https://knowledgecenter.2checkout.com/Integration/03SOAP_API/API_Migration_Guide

It seems that some people are still using the current 2checkout module without problems, so we should maintain backward compatibility. These are the changes I propose:

• Update the gateway management page to have a "API Version" dropdown.
  • The options should be "v1.0" and "v3.0"
  • The credential fields should be updated via js when the version changes. The new fields should be: 'Merchant Code' and 'Secret Key' (we made need other fields as well, we'll see as we develop)
• API interaction should be abstracted to separate classes (one class for each of the two API versions)
  • These two classes should be interchangable (inherit from the same parent) and should be selected based on the afore mentioned drop-down

See the github here for code examples and a php REST client https://github.com/avangate

Apparently 2Checkout was acquired a little while back and things have been changed with their api. See valid documentation here https://www.2checkout.com/documentation/

Known issues:

• Payments are not validating and being applied
• Demo orders are causing errors in the payment process