In this commit we add a call to the new probe endpoint directly into the
loop-in quote call. Furthermore we add an option to include private
channels in the loopin swap payment request. This is also useful for when
users quote/probe directly using the client API and specify hop hints.
Formatting our error was stifling any grpc error returned by the
server. Instead, we bubble up our grpc error, setting an unknown
code if the server did not specifically return an error code.
Add a new failure state that the server may send to the client.
This state is sent for loop in swaps where the client has
erroneously published multiple outputs for a loop in swap (this
could happen if an end user created an external tx with too many
outputs). Failing the swap server side protects users from potential
footguns where they publish the hltc then the server can claim more
money than was paid out off chain. This can never happen when the
loop client publishes the htlc because it only ever contains one
output.
There is an open issue for Python gRPC clients that is
currently being debugged grpc/grpc#23172
It can be mitigated server-side by specifying h2 in the metadata header.
From lnd 0.13.0, the SubscribeSingleInvoice rpc will return an EOF
once it has served a final state to the stream. This is handled in
our lndclient wrapper by closing the channels that we send updates/
errors on. When we are exclusively consuming updates from these
streams, we don't need to handle this case because we will receive
our final update and exit. However, in the case where we continue
to listen on the update channels after consuming the final update,
we need to handle this EOF/closed channels case. This is done by
setting the channels to nil after they're closed so that we no
longer select on them but can continue waiting for our other cases
to complete.
We have similar handling in loopout's waitForHtlcSpendConfirmed.
We're going to want more information about our failures going
forward, so we refactor payInvoice to return a full payment
status. The primary change in this commit is that we surface
both types of payment failures (result.err when we fail immediately,
and lnrpc.Failure when our payment is failed back) and return them
in the failure() method, rather than combining this information
at a lower level.