In this commit, we refactor DeleteChannelEdge to use ChannelIDs rather
than ChannelPoints. We do this as the only use of DeleteChannelEdge is
when we are pruning zombie channels from our graph. When running under a
light client, we are unable to obtain the ChannelPoint of each edge due
to the expensive operations required to do so. As a stop-gap, we'll
resort towards using an edge's ChannelID instead, which is already
gossiped between nodes.
This commit removes the MarkEdgeZombie method from channeldb. This
method is currently not used in any live code paths in production, and
is only used in unit tests. However, incorrect usage of this method
could result in an edge being present in both the zombie and channel
indexes, which deviates from any state we would expect to see in
production. Removing the method will help mitigate the potential for
writing incorrect unit tests in the future, by forcing zombie edges to
be created via the relevant, production APIs, e.g. DeleteChannelEdge.
The existing unit tests that use this method have been modified to use
the DeleteChannelEdge instead. No regressions were discovered in the
process.
This commit modifies FetchChanInfos to skip any channels that are not in
the graph at the time of the call. Currently the entire call will fail
if the edge is not found, which stalls a gossip sync in the following
scenario:
1. Remote peer queries for a channel range
2. We return the set of channel ids in that range
3. A channel from that set is removed from the graph, e.g. via close.
4. Remote peer queries for removed edge, causing the query to fail.
To remedy this, we will now skip any edges that are not known in the
database at the time of the query. This prevents the syncer state
machines from halting, which otherwise could only be resolved by
disconnecting and reconnecting.
This commit modifies FilterKnownChanIDs to skip edges that
we ourselves have deemed zombies. This prevents us from requesting
the updates from them, as this wastes bandwidth and cpu cycles.
During the restore process, it may be possible that we have already
heard about our prior edge from a node on the network (or our channel
peers). As a result, we shouldn't exit if this happens, and instead
should continue with the rest of the restoration process.
In this commit, we modify the `AddrsForNode` method to not fail if no
graph node is found. We do this as when the backup is being
restored/created, it's possible that we don't yet have a
NodeAnnouncement for that node.
In this commit, we move the location where we restore the channel status
to within the `RestoreChannelShells` method itself. Before this commit,
we attempted to use `ApplyChanStatus` which creates a DB transaction and
relies on a fully populated channel state, which in the restoration
case, we don't yet have.
In this commit, we extend the graph's FetchChannelEdgesByID and
HasChannelEdge methods to also check the zombie index whenever the edge
to be looked up doesn't exist within the edge index. We do this to
signal to callers that the edge is known, but only as a zombie, and the
only information that we have about the edge are the node public keys of
the two parties involved in the edge.
In the event that an edge does exist within the zombie index, we make
an additional check on edge policies to ensure they are not within the
router's pruning window, indicating that it is a fresh update.
We mark the edges as zombies when pruning them to ensure we don't
attempt to reprocess them later on. This also applies to channels that
have been removed from the graph due to being stale.
In this commit, we add a zombie edge index to the database. This allows
us to quickly determine across restarts whether we're attempting to
process an edge we've previously deemed as zombie.
In this commit, we convert all the `Update` calls which are serial, to
use `Batch` calls which are optimistically batched together for
concurrent writers. This should increase performance slightly during the
initial graph sync, and also updates at tip as we can coalesce more of
these individual transactions into a single transaction.
This commit modifies the invoice registry to handle invoices for which
the preimage is not known yet (hodl invoices). In that case, the
resolution channel passed in from links and resolvers is stored until we
either learn the preimage or want to cancel the htlc.
In this commit, we update the `TestChanSyncFailure` method to pass given
the new behavior around updating borked channel states. In order to do
this, we add a new method to allow the test to clear an existing channel
state. This method may be of independent use in other areas in the
codebase in the future as well.
In this commit, we modify the WitnessCache's
AddPreimage method to accept a variadic number
of preimages. This enables callers to batch
preimage writes in performance critical areas
of the codebase, e.g. the htlcswitch.
Additionally, we lift the computation of the
witnesses' keys outside of the db transaction.
This saves us from having to do hashing inside
and blocking other callers, and limits extraneous
blocking at the call site.
In this commit, we introduce a migration for the message store
sub-bucket that will migrate all keys within it to a new key format.
This new key format is composed of the peer's public key, followed by
the short channel ID, followed by the message type. This migration is
needed in order to provide backwards-compatibility with messages that
were previously stored before the introduction of the new key format.
In this commit, we add a new type (ChannelShell) along with a new
method, RestoreChannelShells which allows a caller to insert a series of
channel shells into the database. These channel shells will allow a
restored node to initiate the DLP protocol and recover their set of
existing channels.
When we insert a channel shell, we re-create the original link node, and
also add the outgoing edge to the channel graph. This way we can be sure
that upon start up, we attempt to connect to the remote peers, and that
the normal graph query commands will operate as expected.
If the ChanStatusRestored flag is set, then we don't need to write or
read the set of commits for a channel as they won't exist. This will be
the case when we restore a channel from an SCB.
