In app purchase - listen for the payment process

Hello,

We use server side verification for apple in-app purchase. In our app we initialize payment as

gonative.iap.purchase({'productID': 'product_id'});

It works really slow - when user clicks the button to pay, he needs to wait 2-3 seconds or more to see in-app purchase modal.

Can we somehow listen for what is happening in communication between gonative and ios in-app purchase functionality? Something like

gonative.iap.purchase().then().catch()

It is not working, but we need something similar just to show user that something is happening and he needs to wait.