Currently, we write out the Channel's `ChannelTypeFeatures` as an
odd type, implying clients which don't understand the
`ChannelTypeFeatures` field can simply ignore it. This is obviously
nonsense if the channel type is some future version - the client
needs to fail to deserialize as it doesn't understand the channel's
type.
We adapt the serialization logic here to only write out the
`ChannelTypeFeatures` field if it is something other than
only-static-remote-key, and simply consider that "default" (as it
is the only supported type today). Then, we write out the channel
type as an even TLV, implying clients which do not understand it
must fail to read the `Channel`.
Note that we do not need to bother reserving the TLV type no longer
written as it never appeared in a release (merged post-0.0.103).
In order to test Scorer hermetically, sleeps must be avoided. Add a
SinceEpoch abstraction for manually advancing time. Implement the Time
trait for SinceEpoch so that it can be used with ScorerUsingTime in
tests.
The bindings don't currently support passing `Vec`s of objects
which it mappes as "opaque types". This is because it will require
clones to convert its own list of references to Rust's list of
objects.
In the near future we should resolve this limitation, allowing us
to revert this (and make `find_route`'s method signature similarly
cleaner), but for now we must avoid `Vec<OpaqueType>`.
Scorer should be serialized to retain penalty data between restarts.
Implement (de)serialization for Scorer by serializing last failure times
as duration since the UNIX epoch. For no-std, the zero-Duration is used.
Scorer uses time to determine how much to penalize a channel after a
failure occurs. Parameterizing it by time cleans up the code such that
no-std support is in a single AlwaysPresent struct, which implements the
Time trait. Time is implemented for std::time::Instant when std is
available.
This parameterization also allows for deterministic testing since a
clock could be devised to advance forward as needed.
Move channel failure penalty logic into a ChannelFailure abstraction.
This encapsulates the logic for accumulating penalties and decaying them
over time. It also is responsible for the no-std behavior. This cleans
up Scorer and will make it easier to serialize it.
NetworkGraph is owned by NetGraphMsgHandler, but DefaultRouter requires
a reference to it. Introduce shared ownership to NetGraphMsgHandler so
that both can use the same NetworkGraph.
This rewrites a good chunk of the retry logic in `InvoicePayer` to
address two issues:
* it was not considering the return value of `send_payment` (and
`retry_payment`) may indicate a failure on some paths but not
others,
* it was not considering that more failures may still come later
when removing elements from the retry count map. This could
result in us seeing an MPP-partial-failure, failing to retry,
removing the retries count entry, and then retrying other parts,
potentially forever.
Users can provide anything they want as `RouteParameters` so we
shouldn't assume any fields are set any particular way, including
`expiry_time` set at all.
As payments fail, the channel responsible for the failure may be
penalized. Implement Scorer::payment_path_failed to penalize the failed
channel using a configured penalty. As time passes, the penalty is
reduced using exponential decay, though penalties will accumulate if the
channel continues to fail. The decay interval is also configurable.
Upon receiving a PaymentPathFailed event, the failing payment may be
retried on a different path. To avoid using the channel responsible for
the failure, a scorer should be notified of the failure before being
used to find a new route.
Add a payment_path_failed method to routing::Score and call it in
InvoicePayer's event handler. Introduce a LockableScore parameterization
to InvoicePayer so the scorer is locked only once before calling
find_route.
This ensures we don't let a hung connection stick around forever if
the peer never completes the initial handshake.
This also resolves a race where, on receiving a second connection
from a peer, we may reset their_node_id to None to prevent sending
messages even though the `channel_encryptor`
`is_ready_for_encryption()`. Sending pings only checks the
`channel_encryptor` status, not `their_node_id` resulting in an
`unwrap` on `None` in `enqueue_message`.
