This commit adds a channel event store to the channel fitness
package which is used to manage tracking of a node's channels.
It adds tracking for channel open/closed and peer online/offline
events for all channels that a node has open.
Events are consumed from channelNotifier and peerNotifier event
subscriptions. If either of these subscriptions is cancelled,
channel scoring stops, because both subscriptions are expected
to run until node shutdown.
Two functions are exposed to allow external callers to get uptime
information about a channel. GetLifespan returns the period over
which the channel has been monitored. GetUptime returns the channel's
uptime over a specified period. Callers can use these functions to
get the channel's remote peer uptime over its entire lifetime, or
a subset of that period.
This commit adds a chanfitness package which will be used to track
channel health and performance metrics. It adds a channel event
structure which will be used to track channel opens/closes and peer
uptime.
The eventLog implements an uptime function which calcualtes uptime
over a given period and a lifespan function which returns the time
when the log began monitoring the channel and, if the channel is
closed, the time when it stopped moitoring it.
In the scenario where the requested channel does not have enough balance
and another channel towards the same node generates a different failure,
we erroneously returned UnknownNextPeer instead of the expected
TemporaryChannelFailure.
This commit rewrites the non-strict forwarding logic in the switch to
return the proper failure message. Part of this is moving the link
balance check inside the link.
This commit changes mission control to partially base the estimated
probability for untried connections on historical results obtained in
previous payment attempts. This incentivizes routing nodes to keep all
of their channels in good shape.
Probability estimates are amount dependent. Previously we assumed an
amount, but that starts to make less sense when we make probability more
dependent on amounts in the future.
This commit modifies the interpretation of node-level failures.
Previously only the failing node was marked. With this commit, also the
incoming and outgoing connections involved in the route are marked as
failed.
The change prepares for the removal of node-level failures in mission
control probability estimation.
This commit changes the in-memory structure of the mission control
state. It prepares for calculation of a node probability. For this we
need to be able to efficiently look up the last results for all channels
of a node.
Earlier GetCFilter could return a nil-error along with a nil-filter in
cases where we failed to fetch the filter. We would just ignore the
block causing us to miss potential crucial information.
Now that GetCFilter will return an error in cases where the fetch
failed, the filter will never be nil (even for blocks with only coinbase
transactions), and we'll instead return an error.
We also increase the number of retries for the filter from the default 2
to 5.
This sets the `jstype` option to `JS_STRING` for all `chan_id` fields
in the proto rpc definition. `chan_id` is a 64 bit integer, which is
not natively supported by javascript's floating-point `number` with
only 52 bit precision. Nevertheless, by default protobuf will use the
`number` type for 64 bit integer fields in javascript, which can cause
loss of precision problems with `chan_id`. Explicitly setting the type
for javascript as a string will prevent these issues, and should not
interfere with its use as an identifier.
