In this commit we fix a compatibility issue with other implementations.
Before this commit, when writing out an onion error that includes a
`ChannelUpdate` we would use the `MaxPayloadLength` to get the length to
encode. However, a recent update has modified that to be the max
`brontide` payload length as it's possible to pad out the message with
optional fields we're unaware of. As a result, we would always write out
a length of 65KB or so. This didn't effect our parser as we ignore the
length and decode the channel update directly as we don't need the
length to do that. However, other implementations depended on the length
rather than just reading the channel update, meaning that they weren't
able to decode our onion errors that had channel updates.
In this commit we fix that by introducing a new
`writeOnionErrorChanUpdate` which will write out the precise length
instead of using the max payload size.
Fixes#2450.
In this commit, we modify the peer's writeMessage
method to properly handle errors returned from
encoding an lnwire message and from setting the
write deadline on the connection. Since an error
would likely result in an empty byte slice, the
worse case seems to be that we may have tried to
send an empty message on the wire.
Lastly, we correct the way we compute bytes sent
on the wire to properly count the number of bytes
*written*, and not just the length of the encoded
message.
Since NodeScores no longer returns fully populated AttachmentDirectives,
we make this explicit by defining a new type NodeScore that includes a
subset of what the AttachmentDirective does.
We create a new type NodeScore which is a tuple (NodeID, score). The
weightedChoice and chooseN algorithms are altered to expect this type.
This is done in order to simplify the types we are using, since we were
only using a subset of the fields in AttachmentDirective.
Since we want to combine scores from multiple heuristics, things get
complicated if the heuristics report their own individual channel sizes.
Therefore we change the NodeScores interface slightly, letting the agent
specify the wanted channel size, and let the heuristic score the nodes
accordingly.
We let the agent call ChannelBudget on its constraints directly, and
not go through the heuristic. This is needed since when we want to have
multiple active heuristics concurrently, it won't make sense anymore to
ask each of the heuristics.
The mockConstraints are also updated to act as the mockHeuristic did
before, by making it possible to control the responses it gives by
sending them on the contained channels.
To decouple the autopilot heuristic from the constraints, we start by
abstracting them behind an interface to make them easier to mock. We
also rename them HeuristicConstraints->AgentConstraints to make it clear
that they are now constraints the agent must adhere to.
In this commit, we ensure that when we read node aliases from the wire,
we ensure that they're valid. Before this commit, we would read the raw
bytes without checking for validity which could result in us writing in
invalid node alias to disk. We've fixed this, and also updated the
quickcheck tests to generate valid strings.