//! # }
//! ```
//!
+//! # Note
+//!
+//! If persisting [`Scorer`], it must be restored using the same [`Time`] parameterization. Using a
+//! different type results in undefined behavior. Specifically, persisting when built with feature
+//! `no-std` and restoring without it, or vice versa, uses different types and thus is undefined.
+//!
//! [`find_route`]: crate::routing::router::find_route
use routing;
+use ln::msgs::DecodeError;
use routing::network_graph::NodeId;
use routing::router::RouteHop;
+use util::ser::{Readable, Writeable, Writer};
use prelude::*;
+use core::ops::Sub;
use core::time::Duration;
+use io::{self, Read};
/// [`routing::Score`] implementation that provides reasonable default behavior.
///
/// [`routing::Score`] implementation parameterized by [`Time`].
///
/// See [`Scorer`] for details.
+///
+/// # Note
+///
+/// Mixing [`Time`] types between serialization and deserialization results in undefined behavior.
pub struct ScorerUsingTime<T: Time> {
params: ScoringParameters,
// TODO: Remove entries of closed channels.
pub failure_penalty_half_life: Duration,
}
+impl_writeable_tlv_based!(ScoringParameters, {
+ (0, base_penalty_msat, required),
+ (2, failure_penalty_msat, required),
+ (4, failure_penalty_half_life, required),
+});
+
/// Accounting for penalties against a channel for failing to relay any payments.
///
/// Penalties decay over time, though accumulate as more failures occur.
}
/// A measurement of time.
-pub trait Time {
+pub trait Time: Sub<Duration, Output = Self> where Self: Sized {
/// Returns an instance corresponding to the current moment.
fn now() -> Self;
/// Returns the amount of time elapsed since `self` was created.
fn elapsed(&self) -> Duration;
+
+ /// Returns the amount of time passed since the beginning of [`Time`].
+ ///
+ /// Used during (de-)serialization.
+ fn duration_since_epoch() -> Duration;
}
impl<T: Time> ScorerUsingTime<T> {
self.params.base_penalty_msat + failure_penalty_msat
}
- fn payment_path_failed(&mut self, _path: &Vec<RouteHop>, short_channel_id: u64) {
+ fn payment_path_failed(&mut self, _path: &[&RouteHop], short_channel_id: u64) {
let failure_penalty_msat = self.params.failure_penalty_msat;
let half_life = self.params.failure_penalty_half_life;
self.channel_failures
std::time::Instant::now()
}
+ fn duration_since_epoch() -> Duration {
+ use std::time::SystemTime;
+ SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap()
+ }
+
fn elapsed(&self) -> Duration {
std::time::Instant::elapsed(self)
}
}
/// A state in which time has no meaning.
+#[derive(Debug, PartialEq, Eq)]
pub struct Eternity;
impl Time for Eternity {
Self
}
+ fn duration_since_epoch() -> Duration {
+ Duration::from_secs(0)
+ }
+
fn elapsed(&self) -> Duration {
Duration::from_secs(0)
}
}
+
+impl Sub<Duration> for Eternity {
+ type Output = Self;
+
+ fn sub(self, _other: Duration) -> Self {
+ self
+ }
+}
+
+impl<T: Time> Writeable for ScorerUsingTime<T> {
+ #[inline]
+ fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+ self.params.write(w)?;
+ self.channel_failures.write(w)?;
+ write_tlv_fields!(w, {});
+ Ok(())
+ }
+}
+
+impl<T: Time> Readable for ScorerUsingTime<T> {
+ #[inline]
+ fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+ let res = Ok(Self {
+ params: Readable::read(r)?,
+ channel_failures: Readable::read(r)?,
+ });
+ read_tlv_fields!(r, {});
+ res
+ }
+}
+
+impl<T: Time> Writeable for ChannelFailure<T> {
+ #[inline]
+ fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+ let duration_since_epoch = T::duration_since_epoch() - self.last_failed.elapsed();
+ write_tlv_fields!(w, {
+ (0, self.undecayed_penalty_msat, required),
+ (2, duration_since_epoch, required),
+ });
+ Ok(())
+ }
+}
+
+impl<T: Time> Readable for ChannelFailure<T> {
+ #[inline]
+ fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+ let mut undecayed_penalty_msat = 0;
+ let mut duration_since_epoch = Duration::from_secs(0);
+ read_tlv_fields!(r, {
+ (0, undecayed_penalty_msat, required),
+ (2, duration_since_epoch, required),
+ });
+ Ok(Self {
+ undecayed_penalty_msat,
+ last_failed: T::now() - (T::duration_since_epoch() - duration_since_epoch),
+ })
+ }
+}
+
+#[cfg(test)]
+mod tests {
+ use super::{Eternity, ScoringParameters, ScorerUsingTime, Time};
+
+ use routing::Score;
+ use routing::network_graph::NodeId;
+ use util::ser::{Readable, Writeable};
+
+ use bitcoin::secp256k1::PublicKey;
+ use core::cell::Cell;
+ use core::ops::Sub;
+ use core::time::Duration;
+ use io;
+
+ /// Time that can be advanced manually in tests.
+ #[derive(Debug, PartialEq, Eq)]
+ struct SinceEpoch(Duration);
+
+ impl SinceEpoch {
+ thread_local! {
+ static ELAPSED: Cell<Duration> = core::cell::Cell::new(Duration::from_secs(0));
+ }
+
+ fn advance(duration: Duration) {
+ Self::ELAPSED.with(|elapsed| elapsed.set(elapsed.get() + duration))
+ }
+ }
+
+ impl Time for SinceEpoch {
+ fn now() -> Self {
+ Self(Self::duration_since_epoch())
+ }
+
+ fn duration_since_epoch() -> Duration {
+ Self::ELAPSED.with(|elapsed| elapsed.get())
+ }
+
+ fn elapsed(&self) -> Duration {
+ Self::duration_since_epoch() - self.0
+ }
+ }
+
+ impl Sub<Duration> for SinceEpoch {
+ type Output = Self;
+
+ fn sub(self, other: Duration) -> Self {
+ Self(self.0 - other)
+ }
+ }
+
+ #[test]
+ fn time_passes_when_advanced() {
+ let now = SinceEpoch::now();
+ assert_eq!(now.elapsed(), Duration::from_secs(0));
+
+ SinceEpoch::advance(Duration::from_secs(1));
+ SinceEpoch::advance(Duration::from_secs(1));
+
+ let elapsed = now.elapsed();
+ let later = SinceEpoch::now();
+
+ assert_eq!(elapsed, Duration::from_secs(2));
+ assert_eq!(later - elapsed, now);
+ }
+
+ #[test]
+ fn time_never_passes_in_an_eternity() {
+ let now = Eternity::now();
+ let elapsed = now.elapsed();
+ let later = Eternity::now();
+
+ assert_eq!(now.elapsed(), Duration::from_secs(0));
+ assert_eq!(later - elapsed, now);
+ }
+
+ /// A scorer for testing with time that can be manually advanced.
+ type Scorer = ScorerUsingTime::<SinceEpoch>;
+
+ fn source_node_id() -> NodeId {
+ NodeId::from_pubkey(&PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap())
+ }
+
+ fn target_node_id() -> NodeId {
+ NodeId::from_pubkey(&PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap())
+ }
+
+ #[test]
+ fn penalizes_without_channel_failures() {
+ let scorer = Scorer::new(ScoringParameters {
+ base_penalty_msat: 1_000,
+ failure_penalty_msat: 512,
+ failure_penalty_half_life: Duration::from_secs(1),
+ });
+ let source = source_node_id();
+ let target = target_node_id();
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_000);
+
+ SinceEpoch::advance(Duration::from_secs(1));
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_000);
+ }
+
+ #[test]
+ fn accumulates_channel_failure_penalties() {
+ let mut scorer = Scorer::new(ScoringParameters {
+ base_penalty_msat: 1_000,
+ failure_penalty_msat: 64,
+ failure_penalty_half_life: Duration::from_secs(10),
+ });
+ let source = source_node_id();
+ let target = target_node_id();
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_000);
+
+ scorer.payment_path_failed(&[], 42);
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_064);
+
+ scorer.payment_path_failed(&[], 42);
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_128);
+
+ scorer.payment_path_failed(&[], 42);
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_192);
+ }
+
+ #[test]
+ fn decays_channel_failure_penalties_over_time() {
+ let mut scorer = Scorer::new(ScoringParameters {
+ base_penalty_msat: 1_000,
+ failure_penalty_msat: 512,
+ failure_penalty_half_life: Duration::from_secs(10),
+ });
+ let source = source_node_id();
+ let target = target_node_id();
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_000);
+
+ scorer.payment_path_failed(&[], 42);
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_512);
+
+ SinceEpoch::advance(Duration::from_secs(9));
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_512);
+
+ SinceEpoch::advance(Duration::from_secs(1));
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_256);
+
+ SinceEpoch::advance(Duration::from_secs(10 * 8));
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_001);
+
+ SinceEpoch::advance(Duration::from_secs(10));
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_000);
+
+ SinceEpoch::advance(Duration::from_secs(10));
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_000);
+ }
+
+ #[test]
+ fn accumulates_channel_failure_penalties_after_decay() {
+ let mut scorer = Scorer::new(ScoringParameters {
+ base_penalty_msat: 1_000,
+ failure_penalty_msat: 512,
+ failure_penalty_half_life: Duration::from_secs(10),
+ });
+ let source = source_node_id();
+ let target = target_node_id();
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_000);
+
+ scorer.payment_path_failed(&[], 42);
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_512);
+
+ SinceEpoch::advance(Duration::from_secs(10));
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_256);
+
+ scorer.payment_path_failed(&[], 42);
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_768);
+
+ SinceEpoch::advance(Duration::from_secs(10));
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_384);
+ }
+
+ #[test]
+ fn restores_persisted_channel_failure_penalties() {
+ let mut scorer = Scorer::new(ScoringParameters {
+ base_penalty_msat: 1_000,
+ failure_penalty_msat: 512,
+ failure_penalty_half_life: Duration::from_secs(10),
+ });
+ let source = source_node_id();
+ let target = target_node_id();
+
+ scorer.payment_path_failed(&[], 42);
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_512);
+
+ SinceEpoch::advance(Duration::from_secs(10));
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_256);
+
+ scorer.payment_path_failed(&[], 43);
+ assert_eq!(scorer.channel_penalty_msat(43, &source, &target), 1_512);
+
+ let mut serialized_scorer = Vec::new();
+ scorer.write(&mut serialized_scorer).unwrap();
+
+ let deserialized_scorer = <Scorer>::read(&mut io::Cursor::new(&serialized_scorer)).unwrap();
+ assert_eq!(deserialized_scorer.channel_penalty_msat(42, &source, &target), 1_256);
+ assert_eq!(deserialized_scorer.channel_penalty_msat(43, &source, &target), 1_512);
+ }
+
+ #[test]
+ fn decays_persisted_channel_failure_penalties() {
+ let mut scorer = Scorer::new(ScoringParameters {
+ base_penalty_msat: 1_000,
+ failure_penalty_msat: 512,
+ failure_penalty_half_life: Duration::from_secs(10),
+ });
+ let source = source_node_id();
+ let target = target_node_id();
+
+ scorer.payment_path_failed(&[], 42);
+ assert_eq!(scorer.channel_penalty_msat(42, &source, &target), 1_512);
+
+ let mut serialized_scorer = Vec::new();
+ scorer.write(&mut serialized_scorer).unwrap();
+
+ SinceEpoch::advance(Duration::from_secs(10));
+
+ let deserialized_scorer = <Scorer>::read(&mut io::Cursor::new(&serialized_scorer)).unwrap();
+ assert_eq!(deserialized_scorer.channel_penalty_msat(42, &source, &target), 1_256);
+
+ SinceEpoch::advance(Duration::from_secs(10));
+ assert_eq!(deserialized_scorer.channel_penalty_msat(42, &source, &target), 1_128);
+ }
+}
projects / rust-lightning / blobdiff