As part of the preparation to the switch interceptor feature, this
function is changed to return error instead of error channel that
is closed automatically.
Returning an error channel has become complex to maintain and
implement when adding more asynchronous flows to the switch.
The change doesn't affect the current behavior which logs the
errors as before.
This commit extends the link with a new synchronous delivery point for
local UpdateAddHTLC messages. The switch method SendHTLC is updated to
use this delivery point and thereby becomes a synchronous call.
For MPP payments, synchronous hand-off is important. Otherwise the next
pathfinding round could start without the channel balance updated yet.
This fixes an issue where the contract court could leave a completely
swept commit tx unresolved if it was swept by the remote party.
This could happen if (our) commit tx just published was actually a
previously revoked state, in which case the remote party would claim the
funds via a justice transaction.
This manifested itself in the testRevokedCloseRetribution integration
test where at the end of the test Bob was left with a pending channel
that never resolved itself.
The message in the response stream changed. Rename the calls themselves,
to prevent older applications from getting decode errors. Especially
troublesome is the case where the request is executed (send payment),
but the application can't read the outcome (payment sent or not?)
This commit fixes the inconsistency between the payment state as
reported by routerrpc.SendPayment/routerrpc.TrackPayment and the main
rpc ListPayments call.
In addition to that, payment state changes are now sent out for every
state change. This opens the door to user interfaces giving more
feedback to the user about the payment process. This is especially
interesting for multi-part payments.
This commit removes the overflowQueue from the link. We do so in order
to promote better UX for senders, so that HTLCs are failed faster when
the commitment is full. This gives the sender the opportunity to try
another, more open path, rather than perceive the HTLC as being stuck.
At the same time, we remove the total number of active goroutines in lnd
by a factor of N where N is the number of active channels.
