Allow paying before fee is estimated

[bezysoftware]

Often while paying the fee estimation takes a very long time even though it ends up being 1 or even zero hops. It would be nice to set a maximum allowed fee (percentage?) and enable to pay button even while fee estimation is running. This would greatly improve experience while paying for coffee with a line of ppl behind me.

[michaelWuensch]

Thanks for the input.
It is already possible to set a fee limit for lightning transactions in the settings.
From your perspective, what would be the preferred User experience?
A: Don't show a fee estimate at all and just ensure the limit.
B: Calculate the exact fee, but unable to send while it does so (current situation).
C: Calculate fee estimate that can differ from actual fee, but allows sending while calculating.

[bezysoftware]

I would prefer option c). It can keep the ui as is, but enable the send button even when fee is being calculated (progress ring is spinning). Bonus would be showing the maximum possible fee calculated from settings and the invoice amount.

[michaelWuensch]

Ok, thanks.
I'll see what I can do.
After the change, expect the payment to take about as long as the fee calculation did.
The fee calculation was basically sending a payment that fails on purpose. And then using the route it found to actually do the payment. This way it is possible to calculate the fee exactly, but with the drawback of waiting longer.

[bezysoftware]

Thanks. Yes that was my guess, sending a failed payment. But technically the fee is still just a guess because the route might no longer be eligible when I actually pay, right?

[michaelWuensch]

This is done now and shipped with v0.8.0!