fee_msat is empty in InvoicePaid event after channel opening

[darioAnongba]

Hi all,

When receiving a payment for an invoice where a new channel needs to be created, the fee_msat seems to be missing from the InvoicePaid event. We are currently retrieving this value and saving it in DB and it appears to be 0.

Current behaviour

• Create an invoice for an amount, ex: 10k sats
• Paying this invoice necessitates opening a channel: cost 2500 sats
• InvoicePaid event is received: fee_msat is 0

Expected behaviour

• Create an invoice for an amount, ex: 10k sats
• Paying this invoice necessitates opening a channel: cost 2500 sats
• InvoicePaid event is received: fee_msat is 2500 sats

Getting the payment with list_payments or payment_by_hash includes the fee so this is most likely a bug.

Details

Breez SDK Rust version 0.4.1-rc2

[roeierez]

Thanks for the issue @darioAnongba indeed it looks like we including in the event directly the payment received from the node without adding the open channel info. We should probably get the payment from the persistent storage (we already save it) which will contain the missing information.