Generate paymentRequest after clicking googlepay button

[evleen13]

Is there any way that I fetch data on clicking the google pay button and then update the payment request based on the data fetched and then pop up should open with new payment request data.

any help would be appreciated. thanks

[socsieng]

This is something that is discouraged. The reason for that is the browser requires that the payment sheet/payment window is triggered by a user gesture (e.g. button click). The behavior is inconsistent between different browsers, but the user gesture may not be recognized after a fetch.

Which parts of the payment request data are you looking to update? If you are looking to update the total price or shipping options, then one alternative may be to use onPaymentDataChanged callback to achieve this.

Another alternative is to proactively update the payment request when other context in the page changes. For example, if the payment request data is dependent on the value of a checkbox, then fetch the data and update the payment request data when the state of the checkbox changes.

[vsashyn]

Correct me if I'm wrong, but onPaymentDataChanged is triggered only when next callback intents are passed:

  paymentDataRequest.callbackIntents = ["SHIPPING_ADDRESS",  "SHIPPING_OPTION"];

In our flow with digital product we want to avoid requesting shipping address (since it's not needed), so we have only "PAYMENT_AUTHORIZATION". During onPaymentAuthorized callback it's not possible to update price.

[dmengelt]

Aha I see now. The callback is also getting triggered for promo codes/offers if you use callbackIntents: ['OFFER'].

But I guess this is not sufficient for your use case. So I guess you have to proactively update the payment request when there is a discount based on your backend logic. Just as suggested in the initial answer.

1. Call your backend to get the new price
2. Initialize Google Pay with the updated payment request

[vsashyn]

So currently the only way to cover this use case is during rendering. There is no way to do it after click on button, correct ?

[dmengelt]

thats right. but you can always dynamically create a new payment request and call loadPaymentData(paymentRequest)

[vsashyn]

@dmengelt thank you!