Support for WebLN on the payment page

[bumi]

"WebLN is a library and set of specifications for lightning apps and client providers to facilitate communication between apps and users' lightning nodes in a secure way. It provides a programmatic, permissioned interface for letting applications ask users to send payments, generate invoices to receive payments, and much more."

It seems the payment page currently does not implement the WebLN spec but simply provides a lightning: link.
The WebLN spec provides a simple specification on how to request payments from a user programmatically.

It can be added unobtrusively and enhances the checkout experience for people with a Browser supporting WebLN.

[MaxHillebrand]

idk, it says This spec is in early stages, and is subject to change., but the last commit to the repo was June 2019...

I don't know where else it is implemented, other than Joule [which is also not really worked on anymore...]

[MaxHillebrand]

I'm happy to hear that there's such an uptick in usage and implementations! Well done.

I agree that such a UX flow is useful. I can't speak for the technical feasibility / concerns of adding it to btcpay.

Potentially, this could be done in a plugin, but maybe it's a "core feature" worth to put in the main software.

[bumi]

If somebody could point me to the code of the checkout screens I could try to make a PR showing how it could work.

[dennisreimann]

@bumi The template and JS is located here, it's basically a Vue.js app. In general we try to be rather conservative with changes to the checkout. Let me know if you have questions or need help implementing a proof of concept :)

[bumi]

thanks for the pointer. where does it show the lightning invoice?

Is there an API that I maybe do not even have to go through the checkout page? and the checkout page is only the fallback if webln is not available?

[pavlenex]

@bumi There's an API https://docs.btcpayserver.org/API/Greenfield/v1/

[kingonly]

What's the status of this?
Merchants using btcpay are asking us to add them to the Breez marketplace, but we need them to be webln compatible.

[dennisreimann]

Can you elaborate on what exactly is needed? I remember working on integrating WebLN, but to us there was no direct benefit, because the general use cases seemed to work well enough with the lightning: scheme and the existing handlers.

[kingonly]

It's super simple: integrate this in your checkout screen.

It has nothing to do with lightning: scheme. This is for allowing webln hosts (Breez, Alby, Blixt) to seamlessly pay BTC Pay merchants. Bitrefill, LNM, Wavlake, FixedFloat, Boltz, TBC, Geyser, sms4sats, Lightsats, LNCal are just a few examples of sites that have makeInvoice integration and accept funds using webln.

This will allow us (Breez) to embed BTC Pay widgets in our marketplace.