This commit modified the condition to whether drop an existing
connection to a peer when a new connection to this peer is
established.
The previous algorithm used public keys comparison for this decision
which determines that between every two nodes only one of them will
ever drop the connection in such cases.
The problematic case is when a node disconnects and reconnects in a
short interval which is the case of mobile devices.
In such case it takes as much as the "timeout" configured value for
the remote node to detect the "disconnection" (and try to reconnect
if this connection is persistent). In the case this node is also the
one that has the "smaller" public key the reconnect attempts of the
other node will be rejected causing it impossible to fast reconnect.
The solution is to only drop the connection if if we already have a
connected peer that is of the opposite direction from the this new
connection. By doing so the "initiator" will be enabled to replace
the connection and recconnect immediately.
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.
In this commit, we extend the DerivePrivKey method to allow callers that
don't know the full KeyLocator information to attempt to derive a
private key via a brute force mechanism. If we don't now the full
KeyLoactor, then given the KeyFamily, we can walk down the derivation
path and compare keys one by one. In order to ensure we don' t enter an
infinite loop when given an unknown public key, we cap the number of
keys derived at 100k.
An upcoming feature to lnd that adds static channel backups will utilize
this feature, as we need to derive the shachain root given only the
public key and key family, as we don't currently store this KeyLocator
on disk.
