When Payage Trace Mode is switched on, an extra setting appears in the account settings for this gateway: Test Mode. To understand it, we have to explain how PayPal Standard works.
PayPal Standard has two separate ways that a payment can be processed by the originating application. One way is when the browser is redirected back to your site after payment - we call this "the return". Payage receives the request and verifies that the payment has been completed correctly. Payage then updates its payment record and notifies the calling application. But this process can fail, for example if the PayPal account is not configured correctly, or if the user prevents the return by closing the browser or navigating away before the return occurs. This does happen sometimes, so there is a "plan B" - IPN, or "Instant payment notification". IPN messages are requests that PayPal sends directly to your server, separately from any interaction with a user's browser. They can be used to notify payment status changes at any time, including immediately after a payment, or in the case of a refund, and sometimes for other reasons. In order to provide resilience against the "return" failing as described above, Payage handles payment completion by whichever method occurs first. Handling both methods makes the system highly reliable, but only if both methods are working correctly. Test Mode allows you to check this.
There are four options:
| Option | Description |
|---|---|
| Off | Test mode is off |
| Delay Return | Processing of the return from PayPal is delayed by 30 seconds to allow the IPN message to arrive before the return. This doesn't always work, because sometimes the IPN can arrive several minutes (or even longer) after the return, but it can be a useful test. |
| Ignore return | Ignore the return completely. This simulates the situation where the return request never arrives. |
| Delay IPN | Processing of the IPN notification is delayed by 30 seconds to allow the return to complete before the IPN arrives. |
| Ignore IPN | Ignore the IPN completely. This simulates the situation where the IPN request never arrives. |
In all cases, the payment should eventually complete correctly. Test mode is only activated while Trace Mode is switched on.