Multiple `InvoiceReceived` events for single `pay_for_offer` call

[benthecarman]

I had a simple unit test that would spin up 2 nodes and pay a bolt12 offer between them. My InvoiceReceived event handler was not idempotent and would throw if duplicates came in, this caused me to notice that I was receiving multiples of the same event. Found this when upgrading from 0.0.125 to 0.1.1. Can provide logs and code if more info is needed.

Edit: it seems send_payment_for_bolt12_invoice is not idempotent either so this would effect everyone using manually_handle_bolt12_invoices

[jkczyz]

Yeah, we need to check PendingOutboundPayment before generating that event.

We're currently looking into dropping manually_handle_bolt12_invoices and the InvoiceReceived event in favor of a different way of examining BOLT12 messages. Could you describe your use case for needing manually_handle_bolt12_invoices?

[vincenzopalazzo]

Interested in this because I was planning to open an RFC PR to propose removing the ``

Due with #3593 we receive the invoice anyway through the PaymentSend event

[jkczyz]

Thinking about this more, we'll probably want to transition to PendingOutboundPayment::InvoiceReceived in this case, which is currently only used as an ephemeral state. And then allow paying an invoice in this state.

Interested in this because I was planning to open an RFC PR to propose removing the ``

Due with #3593 we receive the invoice anyway through the PaymentSend event

We are iterating on a couple ideas, namely #3412 and #3639.

[benthecarman]

Could you describe your use case for needing manually_handle_bolt12_invoices?

It's so I can save the bolt12 invoice and track the payment

https://github.com/benthecarman/rld/blob/master/src/events.rs#L764