[WIP] showPaymentUI() method

[romandev]

closes #299, #300

The following tasks have been completed:

• web platform tests (link)
• MDN Docs added (link)

Implementation commitment:

• Safari (link to issue)
• Chrome (link to issue)
• Firefox (link to issue)
• Edge (public signal)

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Preview | Diff

[romandev]

@rsolomakhin, @ianbjacobs PTAL

[rsolomakhin]

If both navigator.paymentHandler and navigator.paymentHandler.data are not promises, then the browser has to initialize these objects very early in page load, which can affect page loading performance. Can we make at least one of these into a promise, so that the browser can lazy-instantiate them after the page has loaded?

[dlongley]

paymentHandler.data should be a Promise, IMO. This seemed to work well with the Web Payment CG's original API design where the "payment request" could be retrieved via getPendingRequest:

const paymentRequest = await navigator.payment.getPendingRequest();
// ... handle payment request, generate acknowledgement

// acknowledge payment request handled
navigator.payment.acknowledge(acknowledgement);

https://github.com/Spec-Ops/payment-polyfill#getting-a-pending-payment-request

Here it would be:

const data = await navigator.paymentHandler.data;
// ... handle payment request, generate response

// respond to payment request
navigator.paymentHandler.respondWith(response);

[romandev]

Okay, I agree with this. I'll update this soon.

[ianbjacobs]

(I am going to defer to @rsolomakhin for the details!)

[rsolomakhin]

Does navigator.paymentHandler.respondWith(response) need its own algorithm?

[romandev]

This method simply passes the response data to SW thread. So, I thought that the method's explanation is enough.

[romandev]

To help your understanding, I have a plan to implement POC for this idea. Do you think that it's useful?

[romandev]

Okay, I agree with this. I'll update this soon.

[romandev]

This method simply passes the response data to SW thread. So, I thought that the method's explanation is enough.

[rsolomakhin]

@romandev : I agree that it might be useful to get implementation experience with this feature. Feel free to build it behind a flag. This can guide our discussions in W3C and we can also talk to the payment handler writers about trying out this part of the API.

[webpayments-specs]

Can you please remove me from this thread? Cece Cheam │ Executive Administrator to Ansar Ansari, SVP Digital Payment Products Office: (650)432-5580 │Mobile: (415)542-8167 │ Email: scheam@visa.com<mailto:scheam@visa.com> [https://insite.trusted.visa.com/content/dam/insite/news/Visa%20News/2017/June/email-signature/EmailSig-DynamicFlagVersion.png] From: Rouslan Solomakhin <notifications@github.com> Sent: Thursday, September 27, 2018 10:43 AM To: w3c/payment-handler <payment-handler@noreply.github.com> Cc: Subscribed <subscribed@noreply.github.com> Subject: Re: [w3c/payment-handler] [WIP] showPaymentUI() method (#325) @romandev<https://github.com/romandev> : I agree that it might be useful to get implementation experience with this feature. Feel free to build it behind a flag. This can guide our discussions in W3C and we can also talk to the payment handler writers about trying out this part of the API. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub<#325 (comment)>, or mute the thread<https://github.com/notifications/unsubscribe-auth/AQ8khq43l0EXLuNyUyGJLibfq_Qup-bLks5ufQ4zgaJpZM4W21YO>.