In this commit, we eliminate the three buffered chan error patterns in
the discovery package and replace them with actor.Promise[error]/
actor.Future[error]. The old pattern is error-prone: if a channel is
completed more than once (e.g. when a deferred message copy is
re-enqueued and processed again), the second write to a capacity-1
channel blocks forever. actor.Promise.Complete() is idempotent via
sync.Once, so the second call is always a safe no-op regardless of
whether anyone holds a reference to the Future.
Additionally, PropagateChanPolicyUpdate previously blocked on <-errChan
after enqueuing a policy update with no quit-channel check, creating a
latent deadlock if the gossiper shut down between enqueue and send. It
now uses AwaitGossipResult with a ContextFromQuit-derived context, so
shutdown is always respected.
This is an atomic migration that updates all callers in the same
commit so each commit builds standalone. The three main pieces are:
discovery
networkMsg.err chan error becomes errPromise actor.Promise[error].
chanPolicyUpdateRequest.errChan chan error becomes errPromise.
syncTransitionReq.errChan chan error becomes errPromise. All ~65 sites
that previously wrote to the error channel now call
completeGossipResult(nMsg.errPromise, err) instead.
ProcessRemoteAnnouncement and ProcessLocalAnnouncement now return
actor.Future[error] instead of chan error. The capacity-2 buffer
comment on ProcessRemoteAnnouncement, which was itself a workaround
for the old pattern, is removed along with the TODO referencing the
actor model redesign. ProcessSyncTransition in syncer.go follows the
same pattern: the errChan select is replaced with AwaitGossipResult
using a ContextFromQuit-derived context.
funding
The SendAnnouncement function type in funding.Config changes from
returning chan error to returning actor.Future[error]. The call sites
in addToGraph and announceChannel are updated to await the future with
AwaitGossipResult, passing a context derived from f.quit via
ContextFromQuit. Shutdown signals (context.Canceled and
discovery.ErrGossiperShuttingDown) are both mapped to
ErrFundingManagerShuttingDown via the new mapGossipError helper, which
also factors out the duplicated graph-rejected / unknown-error
handling. The three mock SendAnnouncement implementations in
manager_test.go are updated accordingly.
peer+server
In peer/brontide.go, the ProcessRemoteAnnouncement call in the gossip
stream handler intentionally discards the result since remote gossip
messages are fire-and-forget from the peer's perspective. The old
comment explaining why the chan error was unsafe to use is replaced
with a note that an unawaited Future[error] carries no overhead.
In server.go (applyChannelUpdate), the previous select on errChan and
the quit channel is replaced with ContextFromQuit + AwaitGossipResult.
This is in particular important when running with a postgres
backend.
This only works if you run LND with the native sql flag but
people should run it with this flag from 21 on anyways.
Introduce the WaitingProofInner interface and two concrete
implementations — V1WaitingProof (AnnounceSignatures1) and
V2WaitingProof (AnnounceSignatures2 + optional aggregate MuSig2 nonce).
WaitingProof.Encode/Decode now dispatch on the type prefix byte added
in the previous commit, so the store can transparently persist either
proof variant.
The gossiper is updated with a V1 type assertion to maintain existing
behaviour; full V2 gossiper integration will follow when taproot channel
announcements are wired up.
No live code path creates V2 waiting proofs yet — this commit only
lands the codec and storage readiness so the schema is in place before
new writers are introduced.
In this commit, we move the release note for the improved confirmation
scaling for cooperative closes (PR #10331) from the 0.20.1 release notes
to 0.21.0, where the change actually landed.
The previous commit stopped setting the channel capacity when
retrieving the route. This commit makes sure that in the next
release we remove the entries from the rpc interface.
