USAEPAY blank page on checkout error after upgrade to php7 by host.

[webstorm]

My site address is https://carburetorsandmore.com
My host recently updated me to v7 of php and now my epay module is giving me a blank page on checkout. I've checked and we don't appear to be able to downgrade to a previous version.
The url contains the error string that lets me know what's going on. I've traced it to this section of code.
if ( ($result == false) || ($result < 1) ) {
$payment_error_return = 'payment_error=' . $this->code . '&error=' . urlencode($error) . '&usaepay_api_cc_owner=' . urlencode($_POST['usaepay_api_cc_owner']) . '&usaepay_api_cc_expires_month=' . $_POST['usaepay_api_cc_expires_month'] . '&usaepay_api_cc_expires_year=' . $_POST['usaepay_api_cc_expires_year'];
zen_redirect(zen_href_link(FILENAME_CHECKOUT_PAYMENT, $payment_error_return, 'SSL', true, false));
}


If I comment that out the cart will display the error but won't process cards. With it enabled I get a white screen. Does anyone have any ideas how I could fix it? My ZC is 1.55 and previous to the upgrade to v7 was working properly. The debug log gives me this but it's not a fatal error so I'm not sure if it's an issue. [04-Dec-2017 22:24:54 UTC] PHP Warning: implode(): Invalid arguments passed in /home/carburet/public_html/includes/modules/payment/usaepay_api.php on line 246

[carlwhat]

when posting code, enclose it in code brackets... makes it easier for some of us to read.... see:

https://www.bbcode.org/
https://www.zen-cart.com/misc.php?do=bbcode

i think your supposition, that you can not go back to a php5.6 (or similar version) might be incorrect. your site looks to be hosted here:

http://in2net.com/

and i'm guessing you are probably getting your hosting from a reseller.... whether your reseller has it configured to allow you to go back is up to debate. i'm not sure how tied you are to your host, but if they can not go to 5.6, i think the easiest thing would be to find one that can....

i'm guessing there should be another error logged somewhere to indicate the actual problem. as i would agree that it is probably not the implode.

your payment module (from the ZC plugin downloads) was last updated over 4 years ago, which is a lifetime in payment module code. it is not surprising that it does not work with php7. in addition, the implode line is at 240; while your error log has it at 246, so it looks like it was modified to something different that what i'm looking at.

in addition, i'm guessing that the page that is choking is FILENAME_CHECKOUT_PAYMENT (checkout_payment.php).... but it is hard to tell without more information.... if you could find the actual log, that would be helpful.

finally you could change the implode line to:

//FROM:
    $description = implode("\n", $attrs);
//TO:
    if (is_array($attrs)) { $description = implode("\n", $attrs); }

good luck!