//! and payee using information provided by the payer and from the payee's [`Invoice`], when
//! applicable.
//!
+//! [`InvoicePayer`] is parameterized by a [`LockableScore`], which it uses for scoring failed and
+//! successful payment paths upon receiving [`Event::PaymentPathFailed`] and
+//! [`Event::PaymentPathSuccessful`] events, respectively.
+//!
//! [`InvoicePayer`] is capable of retrying failed payments. It accomplishes this by implementing
//! [`EventHandler`] which decorates a user-provided handler. It will intercept any
//! [`Event::PaymentPathFailed`] events and retry the failed paths for a fixed number of total
//! # &self, _short_channel_id: u64, _send_amt: u64, _chan_amt: Option<u64>, _source: &NodeId, _target: &NodeId
//! # ) -> u64 { 0 }
//! # fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
+//! # fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
//! # }
//! #
//! # struct FakeLogger {}
use std::time::{Duration, SystemTime};
/// A utility for paying [`Invoice`]s and sending spontaneous payments.
+///
+/// See [module-level documentation] for details.
+///
+/// [module-level documentation]: crate::payment
pub struct InvoicePayer<P: Deref, R, S: Deref, L: Deref, E>
where
P::Target: Payer,
if *all_paths_failed { self.payment_cache.lock().unwrap().remove(payment_hash); }
},
+ Event::PaymentPathSuccessful { path, .. } => {
+ let path = path.iter().collect::<Vec<_>>();
+ self.scorer.lock().payment_path_successful(&path);
+ },
Event::PaymentSent { payment_hash, .. } => {
let mut payment_cache = self.payment_cache.lock().unwrap();
let attempts = payment_cache
.expect_send(Amount::ForInvoice(final_value_msat))
.expect_send(Amount::OnRetry(final_value_msat / 2));
let router = TestRouter {};
- let scorer = RefCell::new(TestScorer::new().expect_channel_failure(short_channel_id.unwrap()));
+ let scorer = RefCell::new(TestScorer::new().expect(PaymentPath::Failure {
+ path: path.clone(), short_channel_id: path[0].short_channel_id,
+ }));
let logger = TestLogger::new();
let invoice_payer =
InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(2));
invoice_payer.handle_event(&event);
}
+ #[test]
+ fn scores_successful_channels() {
+ let event_handled = core::cell::RefCell::new(false);
+ let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
+
+ let payment_preimage = PaymentPreimage([1; 32]);
+ let invoice = invoice(payment_preimage);
+ let payment_hash = Some(PaymentHash(invoice.payment_hash().clone().into_inner()));
+ let final_value_msat = invoice.amount_milli_satoshis().unwrap();
+ let route = TestRouter::route_for_value(final_value_msat);
+
+ // Expect that scorer is given short_channel_id upon handling the event.
+ let payer = TestPayer::new().expect_send(Amount::ForInvoice(final_value_msat));
+ let router = TestRouter {};
+ let scorer = RefCell::new(TestScorer::new()
+ .expect(PaymentPath::Success { path: route.paths[0].clone() })
+ .expect(PaymentPath::Success { path: route.paths[1].clone() })
+ );
+ let logger = TestLogger::new();
+ let invoice_payer =
+ InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(2));
+
+ let payment_id = invoice_payer.pay_invoice(&invoice).unwrap();
+ let event = Event::PaymentPathSuccessful {
+ payment_id, payment_hash, path: route.paths[0].clone()
+ };
+ invoice_payer.handle_event(&event);
+ let event = Event::PaymentPathSuccessful {
+ payment_id, payment_hash, path: route.paths[1].clone()
+ };
+ invoice_payer.handle_event(&event);
+ }
+
struct TestRouter;
impl TestRouter {
}
struct TestScorer {
- expectations: VecDeque<u64>,
+ expectations: Option<VecDeque<PaymentPath>>,
+ }
+
+ #[derive(Debug)]
+ enum PaymentPath {
+ Failure { path: Vec<RouteHop>, short_channel_id: u64 },
+ Success { path: Vec<RouteHop> },
}
impl TestScorer {
fn new() -> Self {
Self {
- expectations: VecDeque::new(),
+ expectations: None,
}
}
- fn expect_channel_failure(mut self, short_channel_id: u64) -> Self {
- self.expectations.push_back(short_channel_id);
+ fn expect(mut self, expectation: PaymentPath) -> Self {
+ self.expectations.get_or_insert_with(|| VecDeque::new()).push_back(expectation);
self
}
}
impl lightning::util::ser::Writeable for TestScorer {
fn write<W: lightning::util::ser::Writer>(&self, _: &mut W) -> Result<(), std::io::Error> { unreachable!(); }
}
+
impl Score for TestScorer {
fn channel_penalty_msat(
&self, _short_channel_id: u64, _send_amt: u64, _chan_amt: Option<u64>, _source: &NodeId, _target: &NodeId
) -> u64 { 0 }
- fn payment_path_failed(&mut self, _path: &[&RouteHop], short_channel_id: u64) {
- if let Some(expected_short_channel_id) = self.expectations.pop_front() {
- assert_eq!(short_channel_id, expected_short_channel_id);
+ fn payment_path_failed(&mut self, actual_path: &[&RouteHop], actual_short_channel_id: u64) {
+ if let Some(expectations) = &mut self.expectations {
+ match expectations.pop_front() {
+ Some(PaymentPath::Failure { path, short_channel_id }) => {
+ assert_eq!(actual_path, &path.iter().collect::<Vec<_>>()[..]);
+ assert_eq!(actual_short_channel_id, short_channel_id);
+ },
+ Some(PaymentPath::Success { path }) => {
+ panic!("Unexpected successful payment path: {:?}", path)
+ },
+ None => panic!("Unexpected payment_path_failed call: {:?}", actual_path),
+ }
+ }
+ }
+
+ fn payment_path_successful(&mut self, actual_path: &[&RouteHop]) {
+ if let Some(expectations) = &mut self.expectations {
+ match expectations.pop_front() {
+ Some(PaymentPath::Failure { path, .. }) => {
+ panic!("Unexpected payment path failure: {:?}", path)
+ },
+ Some(PaymentPath::Success { path }) => {
+ assert_eq!(actual_path, &path.iter().collect::<Vec<_>>()[..]);
+ },
+ None => panic!("Unexpected payment_path_successful call: {:?}", actual_path),
+ }
}
}
}
return;
}
- if !self.expectations.is_empty() {
- panic!("Unsatisfied channel failure expectations: {:?}", self.expectations);
+ if let Some(expectations) = &self.expectations {
+ if !expectations.is_empty() {
+ panic!("Unsatisfied scorer expectations: {:?}", expectations);
+ }
}
}
}
/// Handles updating channel penalties after failing to route through a channel.
fn payment_path_failed(&mut self, path: &[&RouteHop], short_channel_id: u64);
+
+ /// Handles updating channel penalties after successfully routing along a path.
+ fn payment_path_successful(&mut self, path: &[&RouteHop]);
}
impl<S: Score, T: DerefMut<Target=S> $(+ $supertrait)*> Score for T {
fn payment_path_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
self.deref_mut().payment_path_failed(path, short_channel_id)
}
+
+ fn payment_path_successful(&mut self, path: &[&RouteHop]) {
+ self.deref_mut().payment_path_successful(path)
+ }
}
} }
/// Used to apply a fixed penalty to each channel, thus avoiding long paths when shorter paths with
/// slightly higher fees are available. Will further penalize channels that fail to relay payments.
///
-/// See [module-level documentation] for usage.
+/// See [module-level documentation] for usage and [`ScoringParameters`] for customization.
///
/// [module-level documentation]: crate::routing::scoring
#[cfg(feature = "no-std")]
/// A penalty in msats to apply to a channel upon failing to relay a payment.
///
/// This accumulates for each failure but may be reduced over time based on
- /// [`failure_penalty_half_life`].
+ /// [`failure_penalty_half_life`] or when successfully routing through a channel.
///
/// Default value: 1,024,000 msat
///
/// The time required to elapse before any accumulated [`failure_penalty_msat`] penalties are
/// cut in half.
///
+ /// Successfully routing through a channel will immediately cut the penalty in half as well.
+ ///
/// # Note
///
/// When built with the `no-std` feature, time will never elapse. Therefore, this penalty will
///
/// Penalties decay over time, though accumulate as more failures occur.
struct ChannelFailure<T: Time> {
- /// Accumulated penalty in msats for the channel as of `last_failed`.
+ /// Accumulated penalty in msats for the channel as of `last_updated`.
undecayed_penalty_msat: u64,
- /// Last time the channel failed. Used to decay `undecayed_penalty_msat`.
- last_failed: T,
+ /// Last time the channel either failed to route or successfully routed a payment. Used to decay
+ /// `undecayed_penalty_msat`.
+ last_updated: T,
}
impl<T: Time> ScorerUsingTime<T> {
fn new(failure_penalty_msat: u64) -> Self {
Self {
undecayed_penalty_msat: failure_penalty_msat,
- last_failed: T::now(),
+ last_updated: T::now(),
}
}
fn add_penalty(&mut self, failure_penalty_msat: u64, half_life: Duration) {
self.undecayed_penalty_msat = self.decayed_penalty_msat(half_life) + failure_penalty_msat;
- self.last_failed = T::now();
+ self.last_updated = T::now();
+ }
+
+ fn reduce_penalty(&mut self, half_life: Duration) {
+ self.undecayed_penalty_msat = self.decayed_penalty_msat(half_life) >> 1;
+ self.last_updated = T::now();
}
fn decayed_penalty_msat(&self, half_life: Duration) -> u64 {
- let decays = self.last_failed.elapsed().as_secs().checked_div(half_life.as_secs());
- match decays {
- Some(decays) => self.undecayed_penalty_msat >> decays,
- None => 0,
- }
+ self.last_updated.elapsed().as_secs()
+ .checked_div(half_life.as_secs())
+ .and_then(|decays| self.undecayed_penalty_msat.checked_shr(decays as u32))
+ .unwrap_or(0)
}
}
.and_modify(|failure| failure.add_penalty(failure_penalty_msat, half_life))
.or_insert_with(|| ChannelFailure::new(failure_penalty_msat));
}
+
+ fn payment_path_successful(&mut self, path: &[&RouteHop]) {
+ let half_life = self.params.failure_penalty_half_life;
+ for hop in path.iter() {
+ self.channel_failures
+ .entry(hop.short_channel_id)
+ .and_modify(|failure| failure.reduce_penalty(half_life));
+ }
+ }
}
impl<T: Time> Writeable for ScorerUsingTime<T> {
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();
+ let duration_since_epoch = T::duration_since_epoch() - self.last_updated.elapsed();
write_tlv_fields!(w, {
(0, self.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),
+ last_updated: T::now() - (T::duration_since_epoch() - duration_since_epoch),
})
}
}
use super::{ScoringParameters, ScorerUsingTime, Time};
use super::time::Eternity;
+ use ln::features::{ChannelFeatures, NodeFeatures};
use routing::scoring::Score;
use routing::network_graph::NodeId;
+ use routing::router::RouteHop;
use util::ser::{Readable, Writeable};
use bitcoin::secp256k1::PublicKey;
assert_eq!(scorer.channel_penalty_msat(42, 1, Some(1), &source, &target), 1_000);
}
+ #[test]
+ fn decays_channel_failure_penalties_without_shift_overflow() {
+ let mut scorer = Scorer::new(ScoringParameters {
+ base_penalty_msat: 1_000,
+ failure_penalty_msat: 512,
+ failure_penalty_half_life: Duration::from_secs(10),
+ overuse_penalty_start_1024th: 1024,
+ overuse_penalty_msat_per_1024th: 0,
+ });
+ let source = source_node_id();
+ let target = target_node_id();
+ assert_eq!(scorer.channel_penalty_msat(42, 1, Some(1), &source, &target), 1_000);
+
+ scorer.payment_path_failed(&[], 42);
+ assert_eq!(scorer.channel_penalty_msat(42, 1, Some(1), &source, &target), 1_512);
+
+ // An unchecked right shift 64 bits or more in ChannelFailure::decayed_penalty_msat would
+ // cause an overflow.
+ SinceEpoch::advance(Duration::from_secs(10 * 64));
+ assert_eq!(scorer.channel_penalty_msat(42, 1, Some(1), &source, &target), 1_000);
+
+ SinceEpoch::advance(Duration::from_secs(10));
+ assert_eq!(scorer.channel_penalty_msat(42, 1, Some(1), &source, &target), 1_000);
+ }
+
#[test]
fn accumulates_channel_failure_penalties_after_decay() {
let mut scorer = Scorer::new(ScoringParameters {
assert_eq!(scorer.channel_penalty_msat(42, 1, Some(1), &source, &target), 1_384);
}
+ #[test]
+ fn reduces_channel_failure_penalties_after_success() {
+ let mut scorer = Scorer::new(ScoringParameters {
+ base_penalty_msat: 1_000,
+ failure_penalty_msat: 512,
+ failure_penalty_half_life: Duration::from_secs(10),
+ overuse_penalty_start_1024th: 1024,
+ overuse_penalty_msat_per_1024th: 0,
+ });
+ let source = source_node_id();
+ let target = target_node_id();
+ assert_eq!(scorer.channel_penalty_msat(42, 1, Some(1), &source, &target), 1_000);
+
+ scorer.payment_path_failed(&[], 42);
+ assert_eq!(scorer.channel_penalty_msat(42, 1, Some(1), &source, &target), 1_512);
+
+ SinceEpoch::advance(Duration::from_secs(10));
+ assert_eq!(scorer.channel_penalty_msat(42, 1, Some(1), &source, &target), 1_256);
+
+ let hop = RouteHop {
+ pubkey: PublicKey::from_slice(target.as_slice()).unwrap(),
+ node_features: NodeFeatures::known(),
+ short_channel_id: 42,
+ channel_features: ChannelFeatures::known(),
+ fee_msat: 1,
+ cltv_expiry_delta: 18,
+ };
+ scorer.payment_path_successful(&[&hop]);
+ assert_eq!(scorer.channel_penalty_msat(42, 1, Some(1), &source, &target), 1_128);
+
+ SinceEpoch::advance(Duration::from_secs(10));
+ assert_eq!(scorer.channel_penalty_msat(42, 1, Some(1), &source, &target), 1_064);
+ }
+
#[test]
fn restores_persisted_channel_failure_penalties() {
let mut scorer = Scorer::new(ScoringParameters {
projects / rust-lightning / commitdiff