In ExpressCheckout mode there are no shipment costs and order items must be specified (even when doing do_express_checkout_payment()). I made some changes to the order, $params building and gave more infromation in the example.
PS. I also think the address 'www.paypal.com/incontext?token=' at which user is redirected after calling $express_checkout->set_express_checkout() should also be set as a constant in Payment class.
In ExpressCheckout mode there are no shipment costs and order items must be specified (even when doing
do_express_checkout_payment()
). I made some changes to the order,$params
building and gave more infromation in the example.PS. I also think the address 'www.paypal.com/incontext?token=' at which user is redirected after calling
$express_checkout->set_express_checkout()
should also be set as a constant in Payment class.