_ Git - rust-lightning/blob - lightning-background-processor/src/lib.rs

   1 //! Utilities that take care of tasks that (1) need to happen periodically to keep Rust-Lightning
   2 //! running properly, and (2) either can or should be run in the background. See docs for
   3 //! [`BackgroundProcessor`] for more details on the nitty-gritty.
   4
   5 // Prefix these with `rustdoc::` when we update our MSRV to be >= 1.52 to remove warnings.
   6 #![deny(broken_intra_doc_links)]
   7 #![deny(private_intra_doc_links)]
   8
   9 #![deny(missing_docs)]
  10 #![cfg_attr(not(feature = "futures"), deny(unsafe_code))]
  11
  12 #![cfg_attr(docsrs, feature(doc_auto_cfg))]
  13
  14 #![cfg_attr(all(not(feature = "std"), not(test)), no_std)]
  15
  16 #[cfg(any(test, feature = "std"))]
  17 extern crate core;
  18
  19 #[cfg(not(feature = "std"))]
  20 extern crate alloc;
  21
  22 #[macro_use] extern crate lightning;
  23 extern crate lightning_rapid_gossip_sync;
  24
  25 use lightning::chain;
  26 use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
  27 use lightning::chain::chainmonitor::{ChainMonitor, Persist};
  28 use lightning::sign::{EntropySource, NodeSigner, SignerProvider};
  29 use lightning::events::{Event, PathFailure};
  30 #[cfg(feature = "std")]
  31 use lightning::events::{EventHandler, EventsProvider};
  32 use lightning::ln::channelmanager::ChannelManager;
  33 use lightning::ln::peer_handler::APeerManager;
  34 use lightning::routing::gossip::{NetworkGraph, P2PGossipSync};
  35 use lightning::routing::utxo::UtxoLookup;
  36 use lightning::routing::router::Router;
  37 use lightning::routing::scoring::{Score, WriteableScore};
  38 use lightning::util::logger::Logger;
  39 use lightning::util::persist::Persister;
  40 #[cfg(feature = "std")]
  41 use lightning::util::wakers::Sleeper;
  42 use lightning_rapid_gossip_sync::RapidGossipSync;
  43
  44 use core::ops::Deref;
  45 use core::time::Duration;
  46
  47 #[cfg(feature = "std")]
  48 use std::sync::Arc;
  49 #[cfg(feature = "std")]
  50 use core::sync::atomic::{AtomicBool, Ordering};
  51 #[cfg(feature = "std")]
  52 use std::thread::{self, JoinHandle};
  53 #[cfg(feature = "std")]
  54 use std::time::Instant;
  55
  56 #[cfg(not(feature = "std"))]
  57 use alloc::vec::Vec;
  58
  59 /// `BackgroundProcessor` takes care of tasks that (1) need to happen periodically to keep
  60 /// Rust-Lightning running properly, and (2) either can or should be run in the background. Its
  61 /// responsibilities are:
  62 /// * Processing [`Event`]s with a user-provided [`EventHandler`].
  63 /// * Monitoring whether the [`ChannelManager`] needs to be re-persisted to disk, and if so,
  64 ///   writing it to disk/backups by invoking the callback given to it at startup.
  65 ///   [`ChannelManager`] persistence should be done in the background.
  66 /// * Calling [`ChannelManager::timer_tick_occurred`], [`ChainMonitor::rebroadcast_pending_claims`]
  67 ///   and [`PeerManager::timer_tick_occurred`] at the appropriate intervals.
  68 /// * Calling [`NetworkGraph::remove_stale_channels_and_tracking`] (if a [`GossipSync`] with a
  69 ///   [`NetworkGraph`] is provided to [`BackgroundProcessor::start`]).
  70 ///
  71 /// It will also call [`PeerManager::process_events`] periodically though this shouldn't be relied
  72 /// upon as doing so may result in high latency.
  73 ///
  74 /// # Note
  75 ///
  76 /// If [`ChannelManager`] persistence fails and the persisted manager becomes out-of-date, then
  77 /// there is a risk of channels force-closing on startup when the manager realizes it's outdated.
  78 /// However, as long as [`ChannelMonitor`] backups are sound, no funds besides those used for
  79 /// unilateral chain closure fees are at risk.
  80 ///
  81 /// [`ChannelMonitor`]: lightning::chain::channelmonitor::ChannelMonitor
  82 /// [`Event`]: lightning::events::Event
  83 /// [`PeerManager::timer_tick_occurred`]: lightning::ln::peer_handler::PeerManager::timer_tick_occurred
  84 /// [`PeerManager::process_events`]: lightning::ln::peer_handler::PeerManager::process_events
  85 #[cfg(feature = "std")]
  86 #[must_use = "BackgroundProcessor will immediately stop on drop. It should be stored until shutdown."]
  87 pub struct BackgroundProcessor {
  88         stop_thread: Arc<AtomicBool>,
  89         thread_handle: Option<JoinHandle<Result<(), std::io::Error>>>,
  90 }
  91
  92 #[cfg(not(test))]
  93 const FRESHNESS_TIMER: u64 = 60;
  94 #[cfg(test)]
  95 const FRESHNESS_TIMER: u64 = 1;
  96
  97 #[cfg(all(not(test), not(debug_assertions)))]
  98 const PING_TIMER: u64 = 10;
  99 /// Signature operations take a lot longer without compiler optimisations.
 100 /// Increasing the ping timer allows for this but slower devices will be disconnected if the
 101 /// timeout is reached.
 102 #[cfg(all(not(test), debug_assertions))]
 103 const PING_TIMER: u64 = 30;
 104 #[cfg(test)]
 105 const PING_TIMER: u64 = 1;
 106
 107 /// Prune the network graph of stale entries hourly.
 108 const NETWORK_PRUNE_TIMER: u64 = 60 * 60;
 109
 110 #[cfg(not(test))]
 111 const SCORER_PERSIST_TIMER: u64 = 60 * 60;
 112 #[cfg(test)]
 113 const SCORER_PERSIST_TIMER: u64 = 1;
 114
 115 #[cfg(not(test))]
 116 const FIRST_NETWORK_PRUNE_TIMER: u64 = 60;
 117 #[cfg(test)]
 118 const FIRST_NETWORK_PRUNE_TIMER: u64 = 1;
 119
 120 #[cfg(not(test))]
 121 const REBROADCAST_TIMER: u64 = 30;
 122 #[cfg(test)]
 123 const REBROADCAST_TIMER: u64 = 1;
 124
 125 #[cfg(feature = "futures")]
 126 /// core::cmp::min is not currently const, so we define a trivial (and equivalent) replacement
 127 const fn min_u64(a: u64, b: u64) -> u64 { if a < b { a } else { b } }
 128 #[cfg(feature = "futures")]
 129 const FASTEST_TIMER: u64 = min_u64(min_u64(FRESHNESS_TIMER, PING_TIMER),
 130         min_u64(SCORER_PERSIST_TIMER, min_u64(FIRST_NETWORK_PRUNE_TIMER, REBROADCAST_TIMER)));
 131
 132 /// Either [`P2PGossipSync`] or [`RapidGossipSync`].
 133 pub enum GossipSync<
 134         P: Deref<Target = P2PGossipSync<G, U, L>>,
 135         R: Deref<Target = RapidGossipSync<G, L>>,
 136         G: Deref<Target = NetworkGraph<L>>,
 137         U: Deref,
 138         L: Deref,
 139 >
 140 where U::Target: UtxoLookup, L::Target: Logger {
 141         /// Gossip sync via the lightning peer-to-peer network as defined by BOLT 7.
 142         P2P(P),
 143         /// Rapid gossip sync from a trusted server.
 144         Rapid(R),
 145         /// No gossip sync.
 146         None,
 147 }
 148
 149 impl<
 150         P: Deref<Target = P2PGossipSync<G, U, L>>,
 151         R: Deref<Target = RapidGossipSync<G, L>>,
 152         G: Deref<Target = NetworkGraph<L>>,
 153         U: Deref,
 154         L: Deref,
 155 > GossipSync<P, R, G, U, L>
 156 where U::Target: UtxoLookup, L::Target: Logger {
 157         fn network_graph(&self) -> Option<&G> {
 158                 match self {
 159                         GossipSync::P2P(gossip_sync) => Some(gossip_sync.network_graph()),
 160                         GossipSync::Rapid(gossip_sync) => Some(gossip_sync.network_graph()),
 161                         GossipSync::None => None,
 162                 }
 163         }
 164
 165         fn prunable_network_graph(&self) -> Option<&G> {
 166                 match self {
 167                         GossipSync::P2P(gossip_sync) => Some(gossip_sync.network_graph()),
 168                         GossipSync::Rapid(gossip_sync) => {
 169                                 if gossip_sync.is_initial_sync_complete() {
 170                                         Some(gossip_sync.network_graph())
 171                                 } else {
 172                                         None
 173                                 }
 174                         },
 175                         GossipSync::None => None,
 176                 }
 177         }
 178 }
 179
 180 /// This is not exported to bindings users as the bindings concretize everything and have constructors for us
 181 impl<P: Deref<Target = P2PGossipSync<G, U, L>>, G: Deref<Target = NetworkGraph<L>>, U: Deref, L: Deref>
 182         GossipSync<P, &RapidGossipSync<G, L>, G, U, L>
 183 where
 184         U::Target: UtxoLookup,
 185         L::Target: Logger,
 186 {
 187         /// Initializes a new [`GossipSync::P2P`] variant.
 188         pub fn p2p(gossip_sync: P) -> Self {
 189                 GossipSync::P2P(gossip_sync)
 190         }
 191 }
 192
 193 /// This is not exported to bindings users as the bindings concretize everything and have constructors for us
 194 impl<'a, R: Deref<Target = RapidGossipSync<G, L>>, G: Deref<Target = NetworkGraph<L>>, L: Deref>
 195         GossipSync<
 196                 &P2PGossipSync<G, &'a (dyn UtxoLookup + Send + Sync), L>,
 197                 R,
 198                 G,
 199                 &'a (dyn UtxoLookup + Send + Sync),
 200                 L,
 201         >
 202 where
 203         L::Target: Logger,
 204 {
 205         /// Initializes a new [`GossipSync::Rapid`] variant.
 206         pub fn rapid(gossip_sync: R) -> Self {
 207                 GossipSync::Rapid(gossip_sync)
 208         }
 209 }
 210
 211 /// This is not exported to bindings users as the bindings concretize everything and have constructors for us
 212 impl<'a, L: Deref>
 213         GossipSync<
 214                 &P2PGossipSync<&'a NetworkGraph<L>, &'a (dyn UtxoLookup + Send + Sync), L>,
 215                 &RapidGossipSync<&'a NetworkGraph<L>, L>,
 216                 &'a NetworkGraph<L>,
 217                 &'a (dyn UtxoLookup + Send + Sync),
 218                 L,
 219         >
 220 where
 221         L::Target: Logger,
 222 {
 223         /// Initializes a new [`GossipSync::None`] variant.
 224         pub fn none() -> Self {
 225                 GossipSync::None
 226         }
 227 }
 228
 229 fn handle_network_graph_update<L: Deref>(
 230         network_graph: &NetworkGraph<L>, event: &Event
 231 ) where L::Target: Logger {
 232         if let Event::PaymentPathFailed {
 233                 failure: PathFailure::OnPath { network_update: Some(ref upd) }, .. } = event
 234         {
 235                 network_graph.handle_network_update(upd);
 236         }
 237 }
 238
 239 /// Updates scorer based on event and returns whether an update occurred so we can decide whether
 240 /// to persist.
 241 fn update_scorer<'a, S: 'static + Deref<Target = SC> + Send + Sync, SC: 'a + WriteableScore<'a>>(
 242         scorer: &'a S, event: &Event
 243 ) -> bool {
 244         let mut score = scorer.lock();
 245         match event {
 246                 Event::PaymentPathFailed { ref path, short_channel_id: Some(scid), .. } => {
 247                         score.payment_path_failed(path, *scid);
 248                 },
 249                 Event::PaymentPathFailed { ref path, payment_failed_permanently: true, .. } => {
 250                         // Reached if the destination explicitly failed it back. We treat this as a successful probe
 251                         // because the payment made it all the way to the destination with sufficient liquidity.
 252                         score.probe_successful(path);
 253                 },
 254                 Event::PaymentPathSuccessful { path, .. } => {
 255                         score.payment_path_successful(path);
 256                 },
 257                 Event::ProbeSuccessful { path, .. } => {
 258                         score.probe_successful(path);
 259                 },
 260                 Event::ProbeFailed { path, short_channel_id: Some(scid), .. } => {
 261                         score.probe_failed(path, *scid);
 262                 },
 263                 _ => return false,
 264         }
 265         true
 266 }
 267
 268 macro_rules! define_run_body {
 269         ($persister: ident, $chain_monitor: ident, $process_chain_monitor_events: expr,
 270          $channel_manager: ident, $process_channel_manager_events: expr,
 271          $gossip_sync: ident, $peer_manager: ident, $logger: ident, $scorer: ident,
 272          $loop_exit_check: expr, $await: expr, $get_timer: expr, $timer_elapsed: expr,
 273          $check_slow_await: expr)
 274         => { {
 275                 log_trace!($logger, "Calling ChannelManager's timer_tick_occurred on startup");
 276                 $channel_manager.timer_tick_occurred();
 277                 log_trace!($logger, "Rebroadcasting monitor's pending claims on startup");
 278                 $chain_monitor.rebroadcast_pending_claims();
 279
 280                 let mut last_freshness_call = $get_timer(FRESHNESS_TIMER);
 281                 let mut last_ping_call = $get_timer(PING_TIMER);
 282                 let mut last_prune_call = $get_timer(FIRST_NETWORK_PRUNE_TIMER);
 283                 let mut last_scorer_persist_call = $get_timer(SCORER_PERSIST_TIMER);
 284                 let mut last_rebroadcast_call = $get_timer(REBROADCAST_TIMER);
 285                 let mut have_pruned = false;
 286
 287                 loop {
 288                         $process_channel_manager_events;
 289                         $process_chain_monitor_events;
 290
 291                         // Note that the PeerManager::process_events may block on ChannelManager's locks,
 292                         // hence it comes last here. When the ChannelManager finishes whatever it's doing,
 293                         // we want to ensure we get into `persist_manager` as quickly as we can, especially
 294                         // without running the normal event processing above and handing events to users.
 295                         //
 296                         // Specifically, on an *extremely* slow machine, we may see ChannelManager start
 297                         // processing a message effectively at any point during this loop. In order to
 298                         // minimize the time between such processing completing and persisting the updated
 299                         // ChannelManager, we want to minimize methods blocking on a ChannelManager
 300                         // generally, and as a fallback place such blocking only immediately before
 301                         // persistence.
 302                         $peer_manager.as_ref().process_events();
 303
 304                         // Exit the loop if the background processor was requested to stop.
 305                         if $loop_exit_check {
 306                                 log_trace!($logger, "Terminating background processor.");
 307                                 break;
 308                         }
 309
 310                         // We wait up to 100ms, but track how long it takes to detect being put to sleep,
 311                         // see `await_start`'s use below.
 312                         let mut await_start = None;
 313                         if $check_slow_await { await_start = Some($get_timer(1)); }
 314                         let updates_available = $await;
 315                         let await_slow = if $check_slow_await { $timer_elapsed(&mut await_start.unwrap(), 1) } else { false };
 316
 317                         // Exit the loop if the background processor was requested to stop.
 318                         if $loop_exit_check {
 319                                 log_trace!($logger, "Terminating background processor.");
 320                                 break;
 321                         }
 322
 323                         if updates_available {
 324                                 log_trace!($logger, "Persisting ChannelManager...");
 325                                 $persister.persist_manager(&*$channel_manager)?;
 326                                 log_trace!($logger, "Done persisting ChannelManager.");
 327                         }
 328                         if $timer_elapsed(&mut last_freshness_call, FRESHNESS_TIMER) {
 329                                 log_trace!($logger, "Calling ChannelManager's timer_tick_occurred");
 330                                 $channel_manager.timer_tick_occurred();
 331                                 last_freshness_call = $get_timer(FRESHNESS_TIMER);
 332                         }
 333                         if await_slow {
 334                                 // On various platforms, we may be starved of CPU cycles for several reasons.
 335                                 // E.g. on iOS, if we've been in the background, we will be entirely paused.
 336                                 // Similarly, if we're on a desktop platform and the device has been asleep, we
 337                                 // may not get any cycles.
 338                                 // We detect this by checking if our max-100ms-sleep, above, ran longer than a
 339                                 // full second, at which point we assume sockets may have been killed (they
 340                                 // appear to be at least on some platforms, even if it has only been a second).
 341                                 // Note that we have to take care to not get here just because user event
 342                                 // processing was slow at the top of the loop. For example, the sample client
 343                                 // may call Bitcoin Core RPCs during event handling, which very often takes
 344                                 // more than a handful of seconds to complete, and shouldn't disconnect all our
 345                                 // peers.
 346                                 log_trace!($logger, "100ms sleep took more than a second, disconnecting peers.");
 347                                 $peer_manager.as_ref().disconnect_all_peers();
 348                                 last_ping_call = $get_timer(PING_TIMER);
 349                         } else if $timer_elapsed(&mut last_ping_call, PING_TIMER) {
 350                                 log_trace!($logger, "Calling PeerManager's timer_tick_occurred");
 351                                 $peer_manager.as_ref().timer_tick_occurred();
 352                                 last_ping_call = $get_timer(PING_TIMER);
 353                         }
 354
 355                         // Note that we want to run a graph prune once not long after startup before
 356                         // falling back to our usual hourly prunes. This avoids short-lived clients never
 357                         // pruning their network graph. We run once 60 seconds after startup before
 358                         // continuing our normal cadence. For RGS, since 60 seconds is likely too long,
 359                         // we prune after an initial sync completes.
 360                         let prune_timer = if have_pruned { NETWORK_PRUNE_TIMER } else { FIRST_NETWORK_PRUNE_TIMER };
 361                         let prune_timer_elapsed = $timer_elapsed(&mut last_prune_call, prune_timer);
 362                         let should_prune = match $gossip_sync {
 363                                 GossipSync::Rapid(_) => !have_pruned || prune_timer_elapsed,
 364                                 _ => prune_timer_elapsed,
 365                         };
 366                         if should_prune {
 367                                 // The network graph must not be pruned while rapid sync completion is pending
 368                                 if let Some(network_graph) = $gossip_sync.prunable_network_graph() {
 369                                         #[cfg(feature = "std")] {
 370                                                 log_trace!($logger, "Pruning and persisting network graph.");
 371                                                 network_graph.remove_stale_channels_and_tracking();
 372                                         }
 373                                         #[cfg(not(feature = "std"))] {
 374                                                 log_warn!($logger, "Not pruning network graph, consider enabling `std` or doing so manually with remove_stale_channels_and_tracking_with_time.");
 375                                                 log_trace!($logger, "Persisting network graph.");
 376                                         }
 377
 378                                         if let Err(e) = $persister.persist_graph(network_graph) {
 379                                                 log_error!($logger, "Error: Failed to persist network graph, check your disk and permissions {}", e)
 380                                         }
 381
 382                                         have_pruned = true;
 383                                 }
 384                                 let prune_timer = if have_pruned { NETWORK_PRUNE_TIMER } else { FIRST_NETWORK_PRUNE_TIMER };
 385                                 last_prune_call = $get_timer(prune_timer);
 386                         }
 387
 388                         if $timer_elapsed(&mut last_scorer_persist_call, SCORER_PERSIST_TIMER) {
 389                                 if let Some(ref scorer) = $scorer {
 390                                         log_trace!($logger, "Persisting scorer");
 391                                         if let Err(e) = $persister.persist_scorer(&scorer) {
 392                                                 log_error!($logger, "Error: Failed to persist scorer, check your disk and permissions {}", e)
 393                                         }
 394                                 }
 395                                 last_scorer_persist_call = $get_timer(SCORER_PERSIST_TIMER);
 396                         }
 397
 398                         if $timer_elapsed(&mut last_rebroadcast_call, REBROADCAST_TIMER) {
 399                                 log_trace!($logger, "Rebroadcasting monitor's pending claims");
 400                                 $chain_monitor.rebroadcast_pending_claims();
 401                                 last_rebroadcast_call = $get_timer(REBROADCAST_TIMER);
 402                         }
 403                 }
 404
 405                 // After we exit, ensure we persist the ChannelManager one final time - this avoids
 406                 // some races where users quit while channel updates were in-flight, with
 407                 // ChannelMonitor update(s) persisted without a corresponding ChannelManager update.
 408                 $persister.persist_manager(&*$channel_manager)?;
 409
 410                 // Persist Scorer on exit
 411                 if let Some(ref scorer) = $scorer {
 412                         $persister.persist_scorer(&scorer)?;
 413                 }
 414
 415                 // Persist NetworkGraph on exit
 416                 if let Some(network_graph) = $gossip_sync.network_graph() {
 417                         $persister.persist_graph(network_graph)?;
 418                 }
 419
 420                 Ok(())
 421         } }
 422 }
 423
 424 #[cfg(feature = "futures")]
 425 pub(crate) mod futures_util {
 426         use core::future::Future;
 427         use core::task::{Poll, Waker, RawWaker, RawWakerVTable};
 428         use core::pin::Pin;
 429         use core::marker::Unpin;
 430         pub(crate) struct Selector<
 431                 A: Future<Output=()> + Unpin, B: Future<Output=()> + Unpin, C: Future<Output=bool> + Unpin
 432         > {
 433                 pub a: A,
 434                 pub b: B,
 435                 pub c: C,
 436         }
 437         pub(crate) enum SelectorOutput {
 438                 A, B, C(bool),
 439         }
 440
 441         impl<
 442                 A: Future<Output=()> + Unpin, B: Future<Output=()> + Unpin, C: Future<Output=bool> + Unpin
 443         > Future for Selector<A, B, C> {
 444                 type Output = SelectorOutput;
 445                 fn poll(mut self: Pin<&mut Self>, ctx: &mut core::task::Context<'_>) -> Poll<SelectorOutput> {
 446                         match Pin::new(&mut self.a).poll(ctx) {
 447                                 Poll::Ready(()) => { return Poll::Ready(SelectorOutput::A); },
 448                                 Poll::Pending => {},
 449                         }
 450                         match Pin::new(&mut self.b).poll(ctx) {
 451                                 Poll::Ready(()) => { return Poll::Ready(SelectorOutput::B); },
 452                                 Poll::Pending => {},
 453                         }
 454                         match Pin::new(&mut self.c).poll(ctx) {
 455                                 Poll::Ready(res) => { return Poll::Ready(SelectorOutput::C(res)); },
 456                                 Poll::Pending => {},
 457                         }
 458                         Poll::Pending
 459                 }
 460         }
 461
 462         // If we want to poll a future without an async context to figure out if it has completed or
 463         // not without awaiting, we need a Waker, which needs a vtable...we fill it with dummy values
 464         // but sadly there's a good bit of boilerplate here.
 465         fn dummy_waker_clone(_: *const ()) -> RawWaker { RawWaker::new(core::ptr::null(), &DUMMY_WAKER_VTABLE) }
 466         fn dummy_waker_action(_: *const ()) { }
 467
 468         const DUMMY_WAKER_VTABLE: RawWakerVTable = RawWakerVTable::new(
 469                 dummy_waker_clone, dummy_waker_action, dummy_waker_action, dummy_waker_action);
 470         pub(crate) fn dummy_waker() -> Waker { unsafe { Waker::from_raw(RawWaker::new(core::ptr::null(), &DUMMY_WAKER_VTABLE)) } }
 471 }
 472 #[cfg(feature = "futures")]
 473 use futures_util::{Selector, SelectorOutput, dummy_waker};
 474 #[cfg(feature = "futures")]
 475 use core::task;
 476
 477 /// Processes background events in a future.
 478 ///
 479 /// `sleeper` should return a future which completes in the given amount of time and returns a
 480 /// boolean indicating whether the background processing should exit. Once `sleeper` returns a
 481 /// future which outputs `true`, the loop will exit and this function's future will complete.
 482 /// The `sleeper` future is free to return early after it has triggered the exit condition.
 483 ///
 484 /// See [`BackgroundProcessor::start`] for information on which actions this handles.
 485 ///
 486 /// Requires the `futures` feature. Note that while this method is available without the `std`
 487 /// feature, doing so will skip calling [`NetworkGraph::remove_stale_channels_and_tracking`],
 488 /// you should call [`NetworkGraph::remove_stale_channels_and_tracking_with_time`] regularly
 489 /// manually instead.
 490 ///
 491 /// The `mobile_interruptable_platform` flag should be set if we're currently running on a
 492 /// mobile device, where we may need to check for interruption of the application regularly. If you
 493 /// are unsure, you should set the flag, as the performance impact of it is minimal unless there
 494 /// are hundreds or thousands of simultaneous process calls running.
 495 ///
 496 /// For example, in order to process background events in a [Tokio](https://tokio.rs/) task, you
 497 /// could setup `process_events_async` like this:
 498 /// ```
 499 /// # struct MyPersister {}
 500 /// # impl lightning::util::persist::KVStorePersister for MyPersister {
 501 /// #     fn persist<W: lightning::util::ser::Writeable>(&self, key: &str, object: &W) -> lightning::io::Result<()> { Ok(()) }
 502 /// # }
 503 /// # struct MyEventHandler {}
 504 /// # impl MyEventHandler {
 505 /// #     async fn handle_event(&self, _: lightning::events::Event) {}
 506 /// # }
 507 /// # #[derive(Eq, PartialEq, Clone, Hash)]
 508 /// # struct MySocketDescriptor {}
 509 /// # impl lightning::ln::peer_handler::SocketDescriptor for MySocketDescriptor {
 510 /// #     fn send_data(&mut self, _data: &[u8], _resume_read: bool) -> usize { 0 }
 511 /// #     fn disconnect_socket(&mut self) {}
 512 /// # }
 513 /// # use std::sync::{Arc, Mutex};
 514 /// # use std::sync::atomic::{AtomicBool, Ordering};
 515 /// # use lightning_background_processor::{process_events_async, GossipSync};
 516 /// # type MyBroadcaster = dyn lightning::chain::chaininterface::BroadcasterInterface + Send + Sync;
 517 /// # type MyFeeEstimator = dyn lightning::chain::chaininterface::FeeEstimator + Send + Sync;
 518 /// # type MyNodeSigner = dyn lightning::sign::NodeSigner + Send + Sync;
 519 /// # type MyUtxoLookup = dyn lightning::routing::utxo::UtxoLookup + Send + Sync;
 520 /// # type MyFilter = dyn lightning::chain::Filter + Send + Sync;
 521 /// # type MyLogger = dyn lightning::util::logger::Logger + Send + Sync;
 522 /// # type MyChainMonitor = lightning::chain::chainmonitor::ChainMonitor<lightning::sign::InMemorySigner, Arc<MyFilter>, Arc<MyBroadcaster>, Arc<MyFeeEstimator>, Arc<MyLogger>, Arc<MyPersister>>;
 523 /// # type MyPeerManager = lightning::ln::peer_handler::SimpleArcPeerManager<MySocketDescriptor, MyChainMonitor, MyBroadcaster, MyFeeEstimator, MyUtxoLookup, MyLogger>;
 524 /// # type MyNetworkGraph = lightning::routing::gossip::NetworkGraph<Arc<MyLogger>>;
 525 /// # type MyGossipSync = lightning::routing::gossip::P2PGossipSync<Arc<MyNetworkGraph>, Arc<MyUtxoLookup>, Arc<MyLogger>>;
 526 /// # type MyChannelManager = lightning::ln::channelmanager::SimpleArcChannelManager<MyChainMonitor, MyBroadcaster, MyFeeEstimator, MyLogger>;
 527 /// # type MyScorer = Mutex<lightning::routing::scoring::ProbabilisticScorer<Arc<MyNetworkGraph>, Arc<MyLogger>>>;
 528 ///
 529 /// # async fn setup_background_processing(my_persister: Arc<MyPersister>, my_event_handler: Arc<MyEventHandler>, my_chain_monitor: Arc<MyChainMonitor>, my_channel_manager: Arc<MyChannelManager>, my_gossip_sync: Arc<MyGossipSync>, my_logger: Arc<MyLogger>, my_scorer: Arc<MyScorer>, my_peer_manager: Arc<MyPeerManager>) {
 530 ///     let background_persister = Arc::clone(&my_persister);
 531 ///     let background_event_handler = Arc::clone(&my_event_handler);
 532 ///     let background_chain_mon = Arc::clone(&my_chain_monitor);
 533 ///     let background_chan_man = Arc::clone(&my_channel_manager);
 534 ///     let background_gossip_sync = GossipSync::p2p(Arc::clone(&my_gossip_sync));
 535 ///     let background_peer_man = Arc::clone(&my_peer_manager);
 536 ///     let background_logger = Arc::clone(&my_logger);
 537 ///     let background_scorer = Arc::clone(&my_scorer);
 538 ///
 539 ///     // Setup the sleeper.
 540 ///     let (stop_sender, stop_receiver) = tokio::sync::watch::channel(());
 541 ///
 542 ///     let sleeper = move |d| {
 543 ///             let mut receiver = stop_receiver.clone();
 544 ///             Box::pin(async move {
 545 ///                     tokio::select!{
 546 ///                             _ = tokio::time::sleep(d) => false,
 547 ///                             _ = receiver.changed() => true,
 548 ///                     }
 549 ///             })
 550 ///     };
 551 ///
 552 ///     let mobile_interruptable_platform = false;
 553 ///
 554 ///     let handle = tokio::spawn(async move {
 555 ///             process_events_async(
 556 ///                     background_persister,
 557 ///                     |e| background_event_handler.handle_event(e),
 558 ///                     background_chain_mon,
 559 ///                     background_chan_man,
 560 ///                     background_gossip_sync,
 561 ///                     background_peer_man,
 562 ///                     background_logger,
 563 ///                     Some(background_scorer),
 564 ///                     sleeper,
 565 ///                     mobile_interruptable_platform,
 566 ///                     )
 567 ///                     .await
 568 ///                     .expect("Failed to process events");
 569 ///     });
 570 ///
 571 ///     // Stop the background processing.
 572 ///     stop_sender.send(()).unwrap();
 573 ///     handle.await.unwrap();
 574 ///     # }
 575 ///```
 576 #[cfg(feature = "futures")]
 577 pub async fn process_events_async<
 578         'a,
 579         UL: 'static + Deref + Send + Sync,
 580         CF: 'static + Deref + Send + Sync,
 581         CW: 'static + Deref + Send + Sync,
 582         T: 'static + Deref + Send + Sync,
 583         ES: 'static + Deref + Send + Sync,
 584         NS: 'static + Deref + Send + Sync,
 585         SP: 'static + Deref + Send + Sync,
 586         F: 'static + Deref + Send + Sync,
 587         R: 'static + Deref + Send + Sync,
 588         G: 'static + Deref<Target = NetworkGraph<L>> + Send + Sync,
 589         L: 'static + Deref + Send + Sync,
 590         P: 'static + Deref + Send + Sync,
 591         EventHandlerFuture: core::future::Future<Output = ()>,
 592         EventHandler: Fn(Event) -> EventHandlerFuture,
 593         PS: 'static + Deref + Send,
 594         M: 'static + Deref<Target = ChainMonitor<<SP::Target as SignerProvider>::Signer, CF, T, F, L, P>> + Send + Sync,
 595         CM: 'static + Deref<Target = ChannelManager<CW, T, ES, NS, SP, F, R, L>> + Send + Sync,
 596         PGS: 'static + Deref<Target = P2PGossipSync<G, UL, L>> + Send + Sync,
 597         RGS: 'static + Deref<Target = RapidGossipSync<G, L>> + Send,
 598         APM: APeerManager + Send + Sync,
 599         PM: 'static + Deref<Target = APM> + Send + Sync,
 600         S: 'static + Deref<Target = SC> + Send + Sync,
 601         SC: for<'b> WriteableScore<'b>,
 602         SleepFuture: core::future::Future<Output = bool> + core::marker::Unpin,
 603         Sleeper: Fn(Duration) -> SleepFuture
 604 >(
 605         persister: PS, event_handler: EventHandler, chain_monitor: M, channel_manager: CM,
 606         gossip_sync: GossipSync<PGS, RGS, G, UL, L>, peer_manager: PM, logger: L, scorer: Option<S>,
 607         sleeper: Sleeper, mobile_interruptable_platform: bool,
 608 ) -> Result<(), lightning::io::Error>
 609 where
 610         UL::Target: 'static + UtxoLookup,
 611         CF::Target: 'static + chain::Filter,
 612         CW::Target: 'static + chain::Watch<<SP::Target as SignerProvider>::Signer>,
 613         T::Target: 'static + BroadcasterInterface,
 614         ES::Target: 'static + EntropySource,
 615         NS::Target: 'static + NodeSigner,
 616         SP::Target: 'static + SignerProvider,
 617         F::Target: 'static + FeeEstimator,
 618         R::Target: 'static + Router,
 619         L::Target: 'static + Logger,
 620         P::Target: 'static + Persist<<SP::Target as SignerProvider>::Signer>,
 621         PS::Target: 'static + Persister<'a, CW, T, ES, NS, SP, F, R, L, SC>,
 622 {
 623         let mut should_break = false;
 624         let async_event_handler = |event| {
 625                 let network_graph = gossip_sync.network_graph();
 626                 let event_handler = &event_handler;
 627                 let scorer = &scorer;
 628                 let logger = &logger;
 629                 let persister = &persister;
 630                 async move {
 631                         if let Some(network_graph) = network_graph {
 632                                 handle_network_graph_update(network_graph, &event)
 633                         }
 634                         if let Some(ref scorer) = scorer {
 635                                 if update_scorer(scorer, &event) {
 636                                         log_trace!(logger, "Persisting scorer after update");
 637                                         if let Err(e) = persister.persist_scorer(&scorer) {
 638                                                 log_error!(logger, "Error: Failed to persist scorer, check your disk and permissions {}", e)
 639                                         }
 640                                 }
 641                         }
 642                         event_handler(event).await;
 643                 }
 644         };
 645         define_run_body!(persister,
 646                 chain_monitor, chain_monitor.process_pending_events_async(async_event_handler).await,
 647                 channel_manager, channel_manager.process_pending_events_async(async_event_handler).await,
 648                 gossip_sync, peer_manager, logger, scorer, should_break, {
 649                         let fut = Selector {
 650                                 a: channel_manager.get_persistable_update_future(),
 651                                 b: chain_monitor.get_update_future(),
 652                                 c: sleeper(if mobile_interruptable_platform { Duration::from_millis(100) } else { Duration::from_secs(FASTEST_TIMER) }),
 653                         };
 654                         match fut.await {
 655                                 SelectorOutput::A => true,
 656                                 SelectorOutput::B => false,
 657                                 SelectorOutput::C(exit) => {
 658                                         should_break = exit;
 659                                         false
 660                                 }
 661                         }
 662                 }, |t| sleeper(Duration::from_secs(t)),
 663                 |fut: &mut SleepFuture, _| {
 664                         let mut waker = dummy_waker();
 665                         let mut ctx = task::Context::from_waker(&mut waker);
 666                         match core::pin::Pin::new(fut).poll(&mut ctx) {
 667                                 task::Poll::Ready(exit) => { should_break = exit; true },
 668                                 task::Poll::Pending => false,
 669                         }
 670                 }, mobile_interruptable_platform)
 671 }
 672
 673 #[cfg(feature = "std")]
 674 impl BackgroundProcessor {
 675         /// Start a background thread that takes care of responsibilities enumerated in the [top-level
 676         /// documentation].
 677         ///
 678         /// The thread runs indefinitely unless the object is dropped, [`stop`] is called, or
 679         /// [`Persister::persist_manager`] returns an error. In case of an error, the error is retrieved by calling
 680         /// either [`join`] or [`stop`].
 681         ///
 682         /// # Data Persistence
 683         ///
 684         /// [`Persister::persist_manager`] is responsible for writing out the [`ChannelManager`] to disk, and/or
 685         /// uploading to one or more backup services. See [`ChannelManager::write`] for writing out a
 686         /// [`ChannelManager`]. See the `lightning-persister` crate for LDK's
 687         /// provided implementation.
 688         ///
 689         /// [`Persister::persist_graph`] is responsible for writing out the [`NetworkGraph`] to disk, if
 690         /// [`GossipSync`] is supplied. See [`NetworkGraph::write`] for writing out a [`NetworkGraph`].
 691         /// See the `lightning-persister` crate for LDK's provided implementation.
 692         ///
 693         /// Typically, users should either implement [`Persister::persist_manager`] to never return an
 694         /// error or call [`join`] and handle any error that may arise. For the latter case,
 695         /// `BackgroundProcessor` must be restarted by calling `start` again after handling the error.
 696         ///
 697         /// # Event Handling
 698         ///
 699         /// `event_handler` is responsible for handling events that users should be notified of (e.g.,
 700         /// payment failed). [`BackgroundProcessor`] may decorate the given [`EventHandler`] with common
 701         /// functionality implemented by other handlers.
 702         /// * [`P2PGossipSync`] if given will update the [`NetworkGraph`] based on payment failures.
 703         ///
 704         /// # Rapid Gossip Sync
 705         ///
 706         /// If rapid gossip sync is meant to run at startup, pass [`RapidGossipSync`] via `gossip_sync`
 707         /// to indicate that the [`BackgroundProcessor`] should not prune the [`NetworkGraph`] instance
 708         /// until the [`RapidGossipSync`] instance completes its first sync.
 709         ///
 710         /// [top-level documentation]: BackgroundProcessor
 711         /// [`join`]: Self::join
 712         /// [`stop`]: Self::stop
 713         /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
 714         /// [`ChannelManager::write`]: lightning::ln::channelmanager::ChannelManager#impl-Writeable
 715         /// [`Persister::persist_manager`]: lightning::util::persist::Persister::persist_manager
 716         /// [`Persister::persist_graph`]: lightning::util::persist::Persister::persist_graph
 717         /// [`NetworkGraph`]: lightning::routing::gossip::NetworkGraph
 718         /// [`NetworkGraph::write`]: lightning::routing::gossip::NetworkGraph#impl-Writeable
 719         pub fn start<
 720                 'a,
 721                 UL: 'static + Deref + Send + Sync,
 722                 CF: 'static + Deref + Send + Sync,
 723                 CW: 'static + Deref + Send + Sync,
 724                 T: 'static + Deref + Send + Sync,
 725                 ES: 'static + Deref + Send + Sync,
 726                 NS: 'static + Deref + Send + Sync,
 727                 SP: 'static + Deref + Send + Sync,
 728                 F: 'static + Deref + Send + Sync,
 729                 R: 'static + Deref + Send + Sync,
 730                 G: 'static + Deref<Target = NetworkGraph<L>> + Send + Sync,
 731                 L: 'static + Deref + Send + Sync,
 732                 P: 'static + Deref + Send + Sync,
 733                 EH: 'static + EventHandler + Send,
 734                 PS: 'static + Deref + Send,
 735                 M: 'static + Deref<Target = ChainMonitor<<SP::Target as SignerProvider>::Signer, CF, T, F, L, P>> + Send + Sync,
 736                 CM: 'static + Deref<Target = ChannelManager<CW, T, ES, NS, SP, F, R, L>> + Send + Sync,
 737                 PGS: 'static + Deref<Target = P2PGossipSync<G, UL, L>> + Send + Sync,
 738                 RGS: 'static + Deref<Target = RapidGossipSync<G, L>> + Send,
 739                 APM: APeerManager + Send + Sync,
 740                 PM: 'static + Deref<Target = APM> + Send + Sync,
 741                 S: 'static + Deref<Target = SC> + Send + Sync,
 742                 SC: for <'b> WriteableScore<'b>,
 743         >(
 744                 persister: PS, event_handler: EH, chain_monitor: M, channel_manager: CM,
 745                 gossip_sync: GossipSync<PGS, RGS, G, UL, L>, peer_manager: PM, logger: L, scorer: Option<S>,
 746         ) -> Self
 747         where
 748                 UL::Target: 'static + UtxoLookup,
 749                 CF::Target: 'static + chain::Filter,
 750                 CW::Target: 'static + chain::Watch<<SP::Target as SignerProvider>::Signer>,
 751                 T::Target: 'static + BroadcasterInterface,
 752                 ES::Target: 'static + EntropySource,
 753                 NS::Target: 'static + NodeSigner,
 754                 SP::Target: 'static + SignerProvider,
 755                 F::Target: 'static + FeeEstimator,
 756                 R::Target: 'static + Router,
 757                 L::Target: 'static + Logger,
 758                 P::Target: 'static + Persist<<SP::Target as SignerProvider>::Signer>,
 759                 PS::Target: 'static + Persister<'a, CW, T, ES, NS, SP, F, R, L, SC>,
 760         {
 761                 let stop_thread = Arc::new(AtomicBool::new(false));
 762                 let stop_thread_clone = stop_thread.clone();
 763                 let handle = thread::spawn(move || -> Result<(), std::io::Error> {
 764                         let event_handler = |event| {
 765                                 let network_graph = gossip_sync.network_graph();
 766                                 if let Some(network_graph) = network_graph {
 767                                         handle_network_graph_update(network_graph, &event)
 768                                 }
 769                                 if let Some(ref scorer) = scorer {
 770                                         if update_scorer(scorer, &event) {
 771                                                 log_trace!(logger, "Persisting scorer after update");
 772                                                 if let Err(e) = persister.persist_scorer(&scorer) {
 773                                                         log_error!(logger, "Error: Failed to persist scorer, check your disk and permissions {}", e)
 774                                                 }
 775                                         }
 776                                 }
 777                                 event_handler.handle_event(event);
 778                         };
 779                         define_run_body!(persister, chain_monitor, chain_monitor.process_pending_events(&event_handler),
 780                                 channel_manager, channel_manager.process_pending_events(&event_handler),
 781                                 gossip_sync, peer_manager, logger, scorer, stop_thread.load(Ordering::Acquire),
 782                                 Sleeper::from_two_futures(
 783                                         channel_manager.get_persistable_update_future(),
 784                                         chain_monitor.get_update_future()
 785                                 ).wait_timeout(Duration::from_millis(100)),
 786                                 |_| Instant::now(), |time: &Instant, dur| time.elapsed().as_secs() > dur, false)
 787                 });
 788                 Self { stop_thread: stop_thread_clone, thread_handle: Some(handle) }
 789         }
 790
 791         /// Join `BackgroundProcessor`'s thread, returning any error that occurred while persisting
 792         /// [`ChannelManager`].
 793         ///
 794         /// # Panics
 795         ///
 796         /// This function panics if the background thread has panicked such as while persisting or
 797         /// handling events.
 798         ///
 799         /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
 800         pub fn join(mut self) -> Result<(), std::io::Error> {
 801                 assert!(self.thread_handle.is_some());
 802                 self.join_thread()
 803         }
 804
 805         /// Stop `BackgroundProcessor`'s thread, returning any error that occurred while persisting
 806         /// [`ChannelManager`].
 807         ///
 808         /// # Panics
 809         ///
 810         /// This function panics if the background thread has panicked such as while persisting or
 811         /// handling events.
 812         ///
 813         /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
 814         pub fn stop(mut self) -> Result<(), std::io::Error> {
 815                 assert!(self.thread_handle.is_some());
 816                 self.stop_and_join_thread()
 817         }
 818
 819         fn stop_and_join_thread(&mut self) -> Result<(), std::io::Error> {
 820                 self.stop_thread.store(true, Ordering::Release);
 821                 self.join_thread()
 822         }
 823
 824         fn join_thread(&mut self) -> Result<(), std::io::Error> {
 825                 match self.thread_handle.take() {
 826                         Some(handle) => handle.join().unwrap(),
 827                         None => Ok(()),
 828                 }
 829         }
 830 }
 831
 832 #[cfg(feature = "std")]
 833 impl Drop for BackgroundProcessor {
 834         fn drop(&mut self) {
 835                 self.stop_and_join_thread().unwrap();
 836         }
 837 }
 838
 839 #[cfg(all(feature = "std", test))]
 840 mod tests {
 841         use bitcoin::blockdata::constants::{genesis_block, ChainHash};
 842         use bitcoin::blockdata::locktime::PackedLockTime;
 843         use bitcoin::blockdata::transaction::{Transaction, TxOut};
 844         use bitcoin::network::constants::Network;
 845         use bitcoin::secp256k1::{SecretKey, PublicKey, Secp256k1};
 846         use lightning::chain::{BestBlock, Confirm, chainmonitor};
 847         use lightning::chain::channelmonitor::ANTI_REORG_DELAY;
 848         use lightning::sign::{InMemorySigner, KeysManager};
 849         use lightning::chain::transaction::OutPoint;
 850         use lightning::events::{Event, PathFailure, MessageSendEventsProvider, MessageSendEvent};
 851         use lightning::{get_event_msg, get_event};
 852         use lightning::ln::PaymentHash;
 853         use lightning::ln::channelmanager;
 854         use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, MIN_CLTV_EXPIRY_DELTA, PaymentId};
 855         use lightning::ln::features::{ChannelFeatures, NodeFeatures};
 856         use lightning::ln::functional_test_utils::*;
 857         use lightning::ln::msgs::{ChannelMessageHandler, Init};
 858         use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
 859         use lightning::routing::gossip::{NetworkGraph, NodeId, P2PGossipSync};
 860         use lightning::routing::router::{DefaultRouter, Path, RouteHop};
 861         use lightning::routing::scoring::{ChannelUsage, Score};
 862         use lightning::util::config::UserConfig;
 863         use lightning::util::ser::Writeable;
 864         use lightning::util::test_utils;
 865         use lightning::util::persist::KVStorePersister;
 866         use lightning_persister::FilesystemPersister;
 867         use std::collections::VecDeque;
 868         use std::{fs, env};
 869         use std::path::PathBuf;
 870         use std::sync::{Arc, Mutex};
 871         use std::sync::mpsc::SyncSender;
 872         use std::time::Duration;
 873         use lightning_rapid_gossip_sync::RapidGossipSync;
 874         use super::{BackgroundProcessor, GossipSync, FRESHNESS_TIMER};
 875
 876         const EVENT_DEADLINE: u64 = 5 * FRESHNESS_TIMER;
 877
 878         #[derive(Clone, Hash, PartialEq, Eq)]
 879         struct TestDescriptor{}
 880         impl SocketDescriptor for TestDescriptor {
 881                 fn send_data(&mut self, _data: &[u8], _resume_read: bool) -> usize {
 882                         0
 883                 }
 884
 885                 fn disconnect_socket(&mut self) {}
 886         }
 887
 888         type ChannelManager =
 889                 channelmanager::ChannelManager<
 890                         Arc<ChainMonitor>,
 891                         Arc<test_utils::TestBroadcaster>,
 892                         Arc<KeysManager>,
 893                         Arc<KeysManager>,
 894                         Arc<KeysManager>,
 895                         Arc<test_utils::TestFeeEstimator>,
 896                         Arc<DefaultRouter<
 897                                 Arc<NetworkGraph<Arc<test_utils::TestLogger>>>,
 898                                 Arc<test_utils::TestLogger>,
 899                                 Arc<Mutex<TestScorer>>,
 900                                 (),
 901                                 TestScorer>
 902                         >,
 903                         Arc<test_utils::TestLogger>>;
 904
 905         type ChainMonitor = chainmonitor::ChainMonitor<InMemorySigner, Arc<test_utils::TestChainSource>, Arc<test_utils::TestBroadcaster>, Arc<test_utils::TestFeeEstimator>, Arc<test_utils::TestLogger>, Arc<FilesystemPersister>>;
 906
 907         type PGS = Arc<P2PGossipSync<Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>>;
 908         type RGS = Arc<RapidGossipSync<Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestLogger>>>;
 909
 910         struct Node {
 911                 node: Arc<ChannelManager>,
 912                 p2p_gossip_sync: PGS,
 913                 rapid_gossip_sync: RGS,
 914                 peer_manager: Arc<PeerManager<TestDescriptor, Arc<test_utils::TestChannelMessageHandler>, Arc<test_utils::TestRoutingMessageHandler>, IgnoringMessageHandler, Arc<test_utils::TestLogger>, IgnoringMessageHandler, Arc<KeysManager>>>,
 915                 chain_monitor: Arc<ChainMonitor>,
 916                 persister: Arc<FilesystemPersister>,
 917                 tx_broadcaster: Arc<test_utils::TestBroadcaster>,
 918                 network_graph: Arc<NetworkGraph<Arc<test_utils::TestLogger>>>,
 919                 logger: Arc<test_utils::TestLogger>,
 920                 best_block: BestBlock,
 921                 scorer: Arc<Mutex<TestScorer>>,
 922         }
 923
 924         impl Node {
 925                 fn p2p_gossip_sync(&self) -> GossipSync<PGS, RGS, Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>> {
 926                         GossipSync::P2P(self.p2p_gossip_sync.clone())
 927                 }
 928
 929                 fn rapid_gossip_sync(&self) -> GossipSync<PGS, RGS, Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>> {
 930                         GossipSync::Rapid(self.rapid_gossip_sync.clone())
 931                 }
 932
 933                 fn no_gossip_sync(&self) -> GossipSync<PGS, RGS, Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>> {
 934                         GossipSync::None
 935                 }
 936         }
 937
 938         impl Drop for Node {
 939                 fn drop(&mut self) {
 940                         let data_dir = self.persister.get_data_dir();
 941                         match fs::remove_dir_all(data_dir.clone()) {
 942                                 Err(e) => println!("Failed to remove test persister directory {}: {}", data_dir, e),
 943                                 _ => {}
 944                         }
 945                 }
 946         }
 947
 948         struct Persister {
 949                 graph_error: Option<(std::io::ErrorKind, &'static str)>,
 950                 graph_persistence_notifier: Option<SyncSender<()>>,
 951                 manager_error: Option<(std::io::ErrorKind, &'static str)>,
 952                 scorer_error: Option<(std::io::ErrorKind, &'static str)>,
 953                 filesystem_persister: FilesystemPersister,
 954         }
 955
 956         impl Persister {
 957                 fn new(data_dir: String) -> Self {
 958                         let filesystem_persister = FilesystemPersister::new(data_dir);
 959                         Self { graph_error: None, graph_persistence_notifier: None, manager_error: None, scorer_error: None, filesystem_persister }
 960                 }
 961
 962                 fn with_graph_error(self, error: std::io::ErrorKind, message: &'static str) -> Self {
 963                         Self { graph_error: Some((error, message)), ..self }
 964                 }
 965
 966                 fn with_graph_persistence_notifier(self, sender: SyncSender<()>) -> Self {
 967                         Self { graph_persistence_notifier: Some(sender), ..self }
 968                 }
 969
 970                 fn with_manager_error(self, error: std::io::ErrorKind, message: &'static str) -> Self {
 971                         Self { manager_error: Some((error, message)), ..self }
 972                 }
 973
 974                 fn with_scorer_error(self, error: std::io::ErrorKind, message: &'static str) -> Self {
 975                         Self { scorer_error: Some((error, message)), ..self }
 976                 }
 977         }
 978
 979         impl KVStorePersister for Persister {
 980                 fn persist<W: Writeable>(&self, key: &str, object: &W) -> std::io::Result<()> {
 981                         if key == "manager" {
 982                                 if let Some((error, message)) = self.manager_error {
 983                                         return Err(std::io::Error::new(error, message))
 984                                 }
 985                         }
 986
 987                         if key == "network_graph" {
 988                                 if let Some(sender) = &self.graph_persistence_notifier {
 989                                         match sender.send(()) {
 990                                                 Ok(()) => {},
 991                                                 Err(std::sync::mpsc::SendError(())) => println!("Persister failed to notify as receiver went away."),
 992                                         }
 993                                 };
 994
 995                                 if let Some((error, message)) = self.graph_error {
 996                                         return Err(std::io::Error::new(error, message))
 997                                 }
 998                         }
 999
1000                         if key == "scorer" {
1001                                 if let Some((error, message)) = self.scorer_error {
1002                                         return Err(std::io::Error::new(error, message))
1003                                 }
1004                         }
1005
1006                         self.filesystem_persister.persist(key, object)
1007                 }
1008         }
1009
1010         struct TestScorer {
1011                 event_expectations: Option<VecDeque<TestResult>>,
1012         }
1013
1014         #[derive(Debug)]
1015         enum TestResult {
1016                 PaymentFailure { path: Path, short_channel_id: u64 },
1017                 PaymentSuccess { path: Path },
1018                 ProbeFailure { path: Path },
1019                 ProbeSuccess { path: Path },
1020         }
1021
1022         impl TestScorer {
1023                 fn new() -> Self {
1024                         Self { event_expectations: None }
1025                 }
1026
1027                 fn expect(&mut self, expectation: TestResult) {
1028                         self.event_expectations.get_or_insert_with(VecDeque::new).push_back(expectation);
1029                 }
1030         }
1031
1032         impl lightning::util::ser::Writeable for TestScorer {
1033                 fn write<W: lightning::util::ser::Writer>(&self, _: &mut W) -> Result<(), lightning::io::Error> { Ok(()) }
1034         }
1035
1036         impl Score for TestScorer {
1037                 type ScoreParams = ();
1038                 fn channel_penalty_msat(
1039                         &self, _short_channel_id: u64, _source: &NodeId, _target: &NodeId, _usage: ChannelUsage, _score_params: &Self::ScoreParams
1040                 ) -> u64 { unimplemented!(); }
1041
1042                 fn payment_path_failed(&mut self, actual_path: &Path, actual_short_channel_id: u64) {
1043                         if let Some(expectations) = &mut self.event_expectations {
1044                                 match expectations.pop_front().unwrap() {
1045                                         TestResult::PaymentFailure { path, short_channel_id } => {
1046                                                 assert_eq!(actual_path, &path);
1047                                                 assert_eq!(actual_short_channel_id, short_channel_id);
1048                                         },
1049                                         TestResult::PaymentSuccess { path } => {
1050                                                 panic!("Unexpected successful payment path: {:?}", path)
1051                                         },
1052                                         TestResult::ProbeFailure { path } => {
1053                                                 panic!("Unexpected probe failure: {:?}", path)
1054                                         },
1055                                         TestResult::ProbeSuccess { path } => {
1056                                                 panic!("Unexpected probe success: {:?}", path)
1057                                         }
1058                                 }
1059                         }
1060                 }
1061
1062                 fn payment_path_successful(&mut self, actual_path: &Path) {
1063                         if let Some(expectations) = &mut self.event_expectations {
1064                                 match expectations.pop_front().unwrap() {
1065                                         TestResult::PaymentFailure { path, .. } => {
1066                                                 panic!("Unexpected payment path failure: {:?}", path)
1067                                         },
1068                                         TestResult::PaymentSuccess { path } => {
1069                                                 assert_eq!(actual_path, &path);
1070                                         },
1071                                         TestResult::ProbeFailure { path } => {
1072                                                 panic!("Unexpected probe failure: {:?}", path)
1073                                         },
1074                                         TestResult::ProbeSuccess { path } => {
1075                                                 panic!("Unexpected probe success: {:?}", path)
1076                                         }
1077                                 }
1078                         }
1079                 }
1080
1081                 fn probe_failed(&mut self, actual_path: &Path, _: u64) {
1082                         if let Some(expectations) = &mut self.event_expectations {
1083                                 match expectations.pop_front().unwrap() {
1084                                         TestResult::PaymentFailure { path, .. } => {
1085                                                 panic!("Unexpected payment path failure: {:?}", path)
1086                                         },
1087                                         TestResult::PaymentSuccess { path } => {
1088                                                 panic!("Unexpected payment path success: {:?}", path)
1089                                         },
1090                                         TestResult::ProbeFailure { path } => {
1091                                                 assert_eq!(actual_path, &path);
1092                                         },
1093                                         TestResult::ProbeSuccess { path } => {
1094                                                 panic!("Unexpected probe success: {:?}", path)
1095                                         }
1096                                 }
1097                         }
1098                 }
1099                 fn probe_successful(&mut self, actual_path: &Path) {
1100                         if let Some(expectations) = &mut self.event_expectations {
1101                                 match expectations.pop_front().unwrap() {
1102                                         TestResult::PaymentFailure { path, .. } => {
1103                                                 panic!("Unexpected payment path failure: {:?}", path)
1104                                         },
1105                                         TestResult::PaymentSuccess { path } => {
1106                                                 panic!("Unexpected payment path success: {:?}", path)
1107                                         },
1108                                         TestResult::ProbeFailure { path } => {
1109                                                 panic!("Unexpected probe failure: {:?}", path)
1110                                         },
1111                                         TestResult::ProbeSuccess { path } => {
1112                                                 assert_eq!(actual_path, &path);
1113                                         }
1114                                 }
1115                         }
1116                 }
1117         }
1118
1119         impl Drop for TestScorer {
1120                 fn drop(&mut self) {
1121                         if std::thread::panicking() {
1122                                 return;
1123                         }
1124
1125                         if let Some(event_expectations) = &self.event_expectations {
1126                                 if !event_expectations.is_empty() {
1127                                         panic!("Unsatisfied event expectations: {:?}", event_expectations);
1128                                 }
1129                         }
1130                 }
1131         }
1132
1133         fn get_full_filepath(filepath: String, filename: String) -> String {
1134                 let mut path = PathBuf::from(filepath);
1135                 path.push(filename);
1136                 path.to_str().unwrap().to_string()
1137         }
1138
1139         fn create_nodes(num_nodes: usize, persist_dir: &str) -> (String, Vec<Node>) {
1140                 let persist_temp_path = env::temp_dir().join(persist_dir);
1141                 let persist_dir = persist_temp_path.to_string_lossy().to_string();
1142                 let network = Network::Bitcoin;
1143                 let mut nodes = Vec::new();
1144                 for i in 0..num_nodes {
1145                         let tx_broadcaster = Arc::new(test_utils::TestBroadcaster::new(network));
1146                         let fee_estimator = Arc::new(test_utils::TestFeeEstimator { sat_per_kw: Mutex::new(253) });
1147                         let logger = Arc::new(test_utils::TestLogger::with_id(format!("node {}", i)));
1148                         let genesis_block = genesis_block(network);
1149                         let network_graph = Arc::new(NetworkGraph::new(network, logger.clone()));
1150                         let scorer = Arc::new(Mutex::new(TestScorer::new()));
1151                         let seed = [i as u8; 32];
1152                         let router = Arc::new(DefaultRouter::new(network_graph.clone(), logger.clone(), seed, scorer.clone(), ()));
1153                         let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Bitcoin));
1154                         let persister = Arc::new(FilesystemPersister::new(format!("{}_persister_{}", &persist_dir, i)));
1155                         let now = Duration::from_secs(genesis_block.header.time as u64);
1156                         let keys_manager = Arc::new(KeysManager::new(&seed, now.as_secs(), now.subsec_nanos()));
1157                         let chain_monitor = Arc::new(chainmonitor::ChainMonitor::new(Some(chain_source.clone()), tx_broadcaster.clone(), logger.clone(), fee_estimator.clone(), persister.clone()));
1158                         let best_block = BestBlock::from_network(network);
1159                         let params = ChainParameters { network, best_block };
1160                         let manager = Arc::new(ChannelManager::new(fee_estimator.clone(), chain_monitor.clone(), tx_broadcaster.clone(), router.clone(), logger.clone(), keys_manager.clone(), keys_manager.clone(), keys_manager.clone(), UserConfig::default(), params, genesis_block.header.time));
1161                         let p2p_gossip_sync = Arc::new(P2PGossipSync::new(network_graph.clone(), Some(chain_source.clone()), logger.clone()));
1162                         let rapid_gossip_sync = Arc::new(RapidGossipSync::new(network_graph.clone(), logger.clone()));
1163                         let msg_handler = MessageHandler {
1164                                 chan_handler: Arc::new(test_utils::TestChannelMessageHandler::new(ChainHash::using_genesis_block(Network::Testnet))),
1165                                 route_handler: Arc::new(test_utils::TestRoutingMessageHandler::new()),
1166                                 onion_message_handler: IgnoringMessageHandler{}, custom_message_handler: IgnoringMessageHandler{}
1167                         };
1168                         let peer_manager = Arc::new(PeerManager::new(msg_handler, 0, &seed, logger.clone(), keys_manager.clone()));
1169                         let node = Node { node: manager, p2p_gossip_sync, rapid_gossip_sync, peer_manager, chain_monitor, persister, tx_broadcaster, network_graph, logger, best_block, scorer };
1170                         nodes.push(node);
1171                 }
1172
1173                 for i in 0..num_nodes {
1174                         for j in (i+1)..num_nodes {
1175                                 nodes[i].node.peer_connected(&nodes[j].node.get_our_node_id(), &Init {
1176                                         features: nodes[j].node.init_features(), networks: None, remote_network_address: None
1177                                 }, true).unwrap();
1178                                 nodes[j].node.peer_connected(&nodes[i].node.get_our_node_id(), &Init {
1179                                         features: nodes[i].node.init_features(), networks: None, remote_network_address: None
1180                                 }, false).unwrap();
1181                         }
1182                 }
1183
1184                 (persist_dir, nodes)
1185         }
1186
1187         macro_rules! open_channel {
1188                 ($node_a: expr, $node_b: expr, $channel_value: expr) => {{
1189                         begin_open_channel!($node_a, $node_b, $channel_value);
1190                         let events = $node_a.node.get_and_clear_pending_events();
1191                         assert_eq!(events.len(), 1);
1192                         let (temporary_channel_id, tx) = handle_funding_generation_ready!(events[0], $channel_value);
1193                         $node_a.node.funding_transaction_generated(&temporary_channel_id, &$node_b.node.get_our_node_id(), tx.clone()).unwrap();
1194                         $node_b.node.handle_funding_created(&$node_a.node.get_our_node_id(), &get_event_msg!($node_a, MessageSendEvent::SendFundingCreated, $node_b.node.get_our_node_id()));
1195                         get_event!($node_b, Event::ChannelPending);
1196                         $node_a.node.handle_funding_signed(&$node_b.node.get_our_node_id(), &get_event_msg!($node_b, MessageSendEvent::SendFundingSigned, $node_a.node.get_our_node_id()));
1197                         get_event!($node_a, Event::ChannelPending);
1198                         tx
1199                 }}
1200         }
1201
1202         macro_rules! begin_open_channel {
1203                 ($node_a: expr, $node_b: expr, $channel_value: expr) => {{
1204                         $node_a.node.create_channel($node_b.node.get_our_node_id(), $channel_value, 100, 42, None).unwrap();
1205                         $node_b.node.handle_open_channel(&$node_a.node.get_our_node_id(), &get_event_msg!($node_a, MessageSendEvent::SendOpenChannel, $node_b.node.get_our_node_id()));
1206                         $node_a.node.handle_accept_channel(&$node_b.node.get_our_node_id(), &get_event_msg!($node_b, MessageSendEvent::SendAcceptChannel, $node_a.node.get_our_node_id()));
1207                 }}
1208         }
1209
1210         macro_rules! handle_funding_generation_ready {
1211                 ($event: expr, $channel_value: expr) => {{
1212                         match $event {
1213                                 Event::FundingGenerationReady { temporary_channel_id, channel_value_satoshis, ref output_script, user_channel_id, .. } => {
1214                                         assert_eq!(channel_value_satoshis, $channel_value);
1215                                         assert_eq!(user_channel_id, 42);
1216
1217                                         let tx = Transaction { version: 1 as i32, lock_time: PackedLockTime(0), input: Vec::new(), output: vec![TxOut {
1218                                                 value: channel_value_satoshis, script_pubkey: output_script.clone(),
1219                                         }]};
1220                                         (temporary_channel_id, tx)
1221                                 },
1222                                 _ => panic!("Unexpected event"),
1223                         }
1224                 }}
1225         }
1226
1227         fn confirm_transaction_depth(node: &mut Node, tx: &Transaction, depth: u32) {
1228                 for i in 1..=depth {
1229                         let prev_blockhash = node.best_block.block_hash();
1230                         let height = node.best_block.height() + 1;
1231                         let header = create_dummy_header(prev_blockhash, height);
1232                         let txdata = vec![(0, tx)];
1233                         node.best_block = BestBlock::new(header.block_hash(), height);
1234                         match i {
1235                                 1 => {
1236                                         node.node.transactions_confirmed(&header, &txdata, height);
1237                                         node.chain_monitor.transactions_confirmed(&header, &txdata, height);
1238                                 },
1239                                 x if x == depth => {
1240                                         node.node.best_block_updated(&header, height);
1241                                         node.chain_monitor.best_block_updated(&header, height);
1242                                 },
1243                                 _ => {},
1244                         }
1245                 }
1246         }
1247         fn confirm_transaction(node: &mut Node, tx: &Transaction) {
1248                 confirm_transaction_depth(node, tx, ANTI_REORG_DELAY);
1249         }
1250
1251         #[test]
1252         fn test_background_processor() {
1253                 // Test that when a new channel is created, the ChannelManager needs to be re-persisted with
1254                 // updates. Also test that when new updates are available, the manager signals that it needs
1255                 // re-persistence and is successfully re-persisted.
1256                 let (persist_dir, nodes) = create_nodes(2, "test_background_processor");
1257
1258                 // Go through the channel creation process so that each node has something to persist. Since
1259                 // open_channel consumes events, it must complete before starting BackgroundProcessor to
1260                 // avoid a race with processing events.
1261                 let tx = open_channel!(nodes[0], nodes[1], 100000);
1262
1263                 // Initiate the background processors to watch each node.
1264                 let data_dir = nodes[0].persister.get_data_dir();
1265                 let persister = Arc::new(Persister::new(data_dir));
1266                 let event_handler = |_: _| {};
1267                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].p2p_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
1268
1269                 macro_rules! check_persisted_data {
1270                         ($node: expr, $filepath: expr) => {
1271                                 let mut expected_bytes = Vec::new();
1272                                 loop {
1273                                         expected_bytes.clear();
1274                                         match $node.write(&mut expected_bytes) {
1275                                                 Ok(()) => {
1276                                                         match std::fs::read($filepath) {
1277                                                                 Ok(bytes) => {
1278                                                                         if bytes == expected_bytes {
1279                                                                                 break
1280                                                                         } else {
1281                                                                                 continue
1282                                                                         }
1283                                                                 },
1284                                                                 Err(_) => continue
1285                                                         }
1286                                                 },
1287                                                 Err(e) => panic!("Unexpected error: {}", e)
1288                                         }
1289                                 }
1290                         }
1291                 }
1292
1293                 // Check that the initial channel manager data is persisted as expected.
1294                 let filepath = get_full_filepath(format!("{}_persister_0", &persist_dir), "manager".to_string());
1295                 check_persisted_data!(nodes[0].node, filepath.clone());
1296
1297                 loop {
1298                         if !nodes[0].node.get_persistence_condvar_value() { break }
1299                 }
1300
1301                 // Force-close the channel.
1302                 nodes[0].node.force_close_broadcasting_latest_txn(&OutPoint { txid: tx.txid(), index: 0 }.to_channel_id(), &nodes[1].node.get_our_node_id()).unwrap();
1303
1304                 // Check that the force-close updates are persisted.
1305                 check_persisted_data!(nodes[0].node, filepath.clone());
1306                 loop {
1307                         if !nodes[0].node.get_persistence_condvar_value() { break }
1308                 }
1309
1310                 // Check network graph is persisted
1311                 let filepath = get_full_filepath(format!("{}_persister_0", &persist_dir), "network_graph".to_string());
1312                 check_persisted_data!(nodes[0].network_graph, filepath.clone());
1313
1314                 // Check scorer is persisted
1315                 let filepath = get_full_filepath(format!("{}_persister_0", &persist_dir), "scorer".to_string());
1316                 check_persisted_data!(nodes[0].scorer, filepath.clone());
1317
1318                 if !std::thread::panicking() {
1319                         bg_processor.stop().unwrap();
1320                 }
1321         }
1322
1323         #[test]
1324         fn test_timer_tick_called() {
1325                 // Test that `ChannelManager::timer_tick_occurred` is called every `FRESHNESS_TIMER`,
1326                 // `ChainMonitor::rebroadcast_pending_claims` is called every `REBROADCAST_TIMER`, and
1327                 // `PeerManager::timer_tick_occurred` every `PING_TIMER`.
1328                 let (_, nodes) = create_nodes(1, "test_timer_tick_called");
1329                 let data_dir = nodes[0].persister.get_data_dir();
1330                 let persister = Arc::new(Persister::new(data_dir));
1331                 let event_handler = |_: _| {};
1332                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].no_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
1333                 loop {
1334                         let log_entries = nodes[0].logger.lines.lock().unwrap();
1335                         let desired_log_1 = "Calling ChannelManager's timer_tick_occurred".to_string();
1336                         let desired_log_2 = "Calling PeerManager's timer_tick_occurred".to_string();
1337                         let desired_log_3 = "Rebroadcasting monitor's pending claims".to_string();
1338                         if log_entries.get(&("lightning_background_processor".to_string(), desired_log_1)).is_some() &&
1339                                 log_entries.get(&("lightning_background_processor".to_string(), desired_log_2)).is_some() &&
1340                                 log_entries.get(&("lightning_background_processor".to_string(), desired_log_3)).is_some() {
1341                                 break
1342                         }
1343                 }
1344
1345                 if !std::thread::panicking() {
1346                         bg_processor.stop().unwrap();
1347                 }
1348         }
1349
1350         #[test]
1351         fn test_channel_manager_persist_error() {
1352                 // Test that if we encounter an error during manager persistence, the thread panics.
1353                 let (_, nodes) = create_nodes(2, "test_persist_error");
1354                 open_channel!(nodes[0], nodes[1], 100000);
1355
1356                 let data_dir = nodes[0].persister.get_data_dir();
1357                 let persister = Arc::new(Persister::new(data_dir).with_manager_error(std::io::ErrorKind::Other, "test"));
1358                 let event_handler = |_: _| {};
1359                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].no_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
1360                 match bg_processor.join() {
1361                         Ok(_) => panic!("Expected error persisting manager"),
1362                         Err(e) => {
1363                                 assert_eq!(e.kind(), std::io::ErrorKind::Other);
1364                                 assert_eq!(e.get_ref().unwrap().to_string(), "test");
1365                         },
1366                 }
1367         }
1368
1369         #[tokio::test]
1370         #[cfg(feature = "futures")]
1371         async fn test_channel_manager_persist_error_async() {
1372                 // Test that if we encounter an error during manager persistence, the thread panics.
1373                 let (_, nodes) = create_nodes(2, "test_persist_error_sync");
1374                 open_channel!(nodes[0], nodes[1], 100000);
1375
1376                 let data_dir = nodes[0].persister.get_data_dir();
1377                 let persister = Arc::new(Persister::new(data_dir).with_manager_error(std::io::ErrorKind::Other, "test"));
1378
1379                 let bp_future = super::process_events_async(
1380                         persister, |_: _| {async {}}, nodes[0].chain_monitor.clone(), nodes[0].node.clone(),
1381                         nodes[0].rapid_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(),
1382                         Some(nodes[0].scorer.clone()), move |dur: Duration| {
1383                                 Box::pin(async move {
1384                                         tokio::time::sleep(dur).await;
1385                                         false // Never exit
1386                                 })
1387                         }, false,
1388                 );
1389                 match bp_future.await {
1390                         Ok(_) => panic!("Expected error persisting manager"),
1391                         Err(e) => {
1392                                 assert_eq!(e.kind(), std::io::ErrorKind::Other);
1393                                 assert_eq!(e.get_ref().unwrap().to_string(), "test");
1394                         },
1395                 }
1396         }
1397
1398         #[test]
1399         fn test_network_graph_persist_error() {
1400                 // Test that if we encounter an error during network graph persistence, an error gets returned.
1401                 let (_, nodes) = create_nodes(2, "test_persist_network_graph_error");
1402                 let data_dir = nodes[0].persister.get_data_dir();
1403                 let persister = Arc::new(Persister::new(data_dir).with_graph_error(std::io::ErrorKind::Other, "test"));
1404                 let event_handler = |_: _| {};
1405                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].p2p_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
1406
1407                 match bg_processor.stop() {
1408                         Ok(_) => panic!("Expected error persisting network graph"),
1409                         Err(e) => {
1410                                 assert_eq!(e.kind(), std::io::ErrorKind::Other);
1411                                 assert_eq!(e.get_ref().unwrap().to_string(), "test");
1412                         },
1413                 }
1414         }
1415
1416         #[test]
1417         fn test_scorer_persist_error() {
1418                 // Test that if we encounter an error during scorer persistence, an error gets returned.
1419                 let (_, nodes) = create_nodes(2, "test_persist_scorer_error");
1420                 let data_dir = nodes[0].persister.get_data_dir();
1421                 let persister = Arc::new(Persister::new(data_dir).with_scorer_error(std::io::ErrorKind::Other, "test"));
1422                 let event_handler = |_: _| {};
1423                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].no_gossip_sync(), nodes[0].peer_manager.clone(),  nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
1424
1425                 match bg_processor.stop() {
1426                         Ok(_) => panic!("Expected error persisting scorer"),
1427                         Err(e) => {
1428                                 assert_eq!(e.kind(), std::io::ErrorKind::Other);
1429                                 assert_eq!(e.get_ref().unwrap().to_string(), "test");
1430                         },
1431                 }
1432         }
1433
1434         #[test]
1435         fn test_background_event_handling() {
1436                 let (_, mut nodes) = create_nodes(2, "test_background_event_handling");
1437                 let channel_value = 100000;
1438                 let data_dir = nodes[0].persister.get_data_dir();
1439                 let persister = Arc::new(Persister::new(data_dir.clone()));
1440
1441                 // Set up a background event handler for FundingGenerationReady events.
1442                 let (funding_generation_send, funding_generation_recv) = std::sync::mpsc::sync_channel(1);
1443                 let (channel_pending_send, channel_pending_recv) = std::sync::mpsc::sync_channel(1);
1444                 let event_handler = move |event: Event| match event {
1445                         Event::FundingGenerationReady { .. } => funding_generation_send.send(handle_funding_generation_ready!(event, channel_value)).unwrap(),
1446                         Event::ChannelPending { .. } => channel_pending_send.send(()).unwrap(),
1447                         Event::ChannelReady { .. } => {},
1448                         _ => panic!("Unexpected event: {:?}", event),
1449                 };
1450
1451                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].no_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
1452
1453                 // Open a channel and check that the FundingGenerationReady event was handled.
1454                 begin_open_channel!(nodes[0], nodes[1], channel_value);
1455                 let (temporary_channel_id, funding_tx) = funding_generation_recv
1456                         .recv_timeout(Duration::from_secs(EVENT_DEADLINE))
1457                         .expect("FundingGenerationReady not handled within deadline");
1458                 nodes[0].node.funding_transaction_generated(&temporary_channel_id, &nodes[1].node.get_our_node_id(), funding_tx.clone()).unwrap();
1459                 nodes[1].node.handle_funding_created(&nodes[0].node.get_our_node_id(), &get_event_msg!(nodes[0], MessageSendEvent::SendFundingCreated, nodes[1].node.get_our_node_id()));
1460                 get_event!(nodes[1], Event::ChannelPending);
1461                 nodes[0].node.handle_funding_signed(&nodes[1].node.get_our_node_id(), &get_event_msg!(nodes[1], MessageSendEvent::SendFundingSigned, nodes[0].node.get_our_node_id()));
1462                 let _ = channel_pending_recv.recv_timeout(Duration::from_secs(EVENT_DEADLINE))
1463                         .expect("ChannelPending not handled within deadline");
1464
1465                 // Confirm the funding transaction.
1466                 confirm_transaction(&mut nodes[0], &funding_tx);
1467                 let as_funding = get_event_msg!(nodes[0], MessageSendEvent::SendChannelReady, nodes[1].node.get_our_node_id());
1468                 confirm_transaction(&mut nodes[1], &funding_tx);
1469                 let bs_funding = get_event_msg!(nodes[1], MessageSendEvent::SendChannelReady, nodes[0].node.get_our_node_id());
1470                 nodes[0].node.handle_channel_ready(&nodes[1].node.get_our_node_id(), &bs_funding);
1471                 let _as_channel_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id());
1472                 nodes[1].node.handle_channel_ready(&nodes[0].node.get_our_node_id(), &as_funding);
1473                 let _bs_channel_update = get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id());
1474
1475                 if !std::thread::panicking() {
1476                         bg_processor.stop().unwrap();
1477                 }
1478
1479                 // Set up a background event handler for SpendableOutputs events.
1480                 let (sender, receiver) = std::sync::mpsc::sync_channel(1);
1481                 let event_handler = move |event: Event| match event {
1482                         Event::SpendableOutputs { .. } => sender.send(event).unwrap(),
1483                         Event::ChannelReady { .. } => {},
1484                         Event::ChannelClosed { .. } => {},
1485                         _ => panic!("Unexpected event: {:?}", event),
1486                 };
1487                 let persister = Arc::new(Persister::new(data_dir));
1488                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].no_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
1489
1490                 // Force close the channel and check that the SpendableOutputs event was handled.
1491                 nodes[0].node.force_close_broadcasting_latest_txn(&nodes[0].node.list_channels()[0].channel_id, &nodes[1].node.get_our_node_id()).unwrap();
1492                 let commitment_tx = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().pop().unwrap();
1493                 confirm_transaction_depth(&mut nodes[0], &commitment_tx, BREAKDOWN_TIMEOUT as u32);
1494
1495                 let event = receiver
1496                         .recv_timeout(Duration::from_secs(EVENT_DEADLINE))
1497                         .expect("Events not handled within deadline");
1498                 match event {
1499                         Event::SpendableOutputs { .. } => {},
1500                         _ => panic!("Unexpected event: {:?}", event),
1501                 }
1502
1503                 if !std::thread::panicking() {
1504                         bg_processor.stop().unwrap();
1505                 }
1506         }
1507
1508         #[test]
1509         fn test_scorer_persistence() {
1510                 let (_, nodes) = create_nodes(2, "test_scorer_persistence");
1511                 let data_dir = nodes[0].persister.get_data_dir();
1512                 let persister = Arc::new(Persister::new(data_dir));
1513                 let event_handler = |_: _| {};
1514                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].no_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
1515
1516                 loop {
1517                         let log_entries = nodes[0].logger.lines.lock().unwrap();
1518                         let expected_log = "Persisting scorer".to_string();
1519                         if log_entries.get(&("lightning_background_processor".to_string(), expected_log)).is_some() {
1520                                 break
1521                         }
1522                 }
1523
1524                 if !std::thread::panicking() {
1525                         bg_processor.stop().unwrap();
1526                 }
1527         }
1528
1529         macro_rules! do_test_not_pruning_network_graph_until_graph_sync_completion {
1530                 ($nodes: expr, $receive: expr, $sleep: expr) => {
1531                         let features = ChannelFeatures::empty();
1532                         $nodes[0].network_graph.add_channel_from_partial_announcement(
1533                                 42, 53, features, $nodes[0].node.get_our_node_id(), $nodes[1].node.get_our_node_id()
1534                         ).expect("Failed to update channel from partial announcement");
1535                         let original_graph_description = $nodes[0].network_graph.to_string();
1536                         assert!(original_graph_description.contains("42: features: 0000, node_one:"));
1537                         assert_eq!($nodes[0].network_graph.read_only().channels().len(), 1);
1538
1539                         loop {
1540                                 $sleep;
1541                                 let log_entries = $nodes[0].logger.lines.lock().unwrap();
1542                                 let loop_counter = "Calling ChannelManager's timer_tick_occurred".to_string();
1543                                 if *log_entries.get(&("lightning_background_processor".to_string(), loop_counter))
1544                                         .unwrap_or(&0) > 1
1545                                 {
1546                                         // Wait until the loop has gone around at least twice.
1547                                         break
1548                                 }
1549                         }
1550
1551                         let initialization_input = vec![
1552                                 76, 68, 75, 1, 111, 226, 140, 10, 182, 241, 179, 114, 193, 166, 162, 70, 174, 99, 247,
1553                                 79, 147, 30, 131, 101, 225, 90, 8, 156, 104, 214, 25, 0, 0, 0, 0, 0, 97, 227, 98, 218,
1554                                 0, 0, 0, 4, 2, 22, 7, 207, 206, 25, 164, 197, 231, 230, 231, 56, 102, 61, 250, 251,
1555                                 187, 172, 38, 46, 79, 247, 108, 44, 155, 48, 219, 238, 252, 53, 192, 6, 67, 2, 36, 125,
1556                                 157, 176, 223, 175, 234, 116, 94, 248, 201, 225, 97, 235, 50, 47, 115, 172, 63, 136,
1557                                 88, 216, 115, 11, 111, 217, 114, 84, 116, 124, 231, 107, 2, 158, 1, 242, 121, 152, 106,
1558                                 204, 131, 186, 35, 93, 70, 216, 10, 237, 224, 183, 89, 95, 65, 3, 83, 185, 58, 138,
1559                                 181, 64, 187, 103, 127, 68, 50, 2, 201, 19, 17, 138, 136, 149, 185, 226, 156, 137, 175,
1560                                 110, 32, 237, 0, 217, 90, 31, 100, 228, 149, 46, 219, 175, 168, 77, 4, 143, 38, 128,
1561                                 76, 97, 0, 0, 0, 2, 0, 0, 255, 8, 153, 192, 0, 2, 27, 0, 0, 0, 1, 0, 0, 255, 2, 68,
1562                                 226, 0, 6, 11, 0, 1, 2, 3, 0, 0, 0, 2, 0, 40, 0, 0, 0, 0, 0, 0, 3, 232, 0, 0, 3, 232,
1563                                 0, 0, 0, 1, 0, 0, 0, 0, 58, 85, 116, 216, 255, 8, 153, 192, 0, 2, 27, 0, 0, 25, 0, 0,
1564                                 0, 1, 0, 0, 0, 125, 255, 2, 68, 226, 0, 6, 11, 0, 1, 5, 0, 0, 0, 0, 29, 129, 25, 192,
1565                         ];
1566                         $nodes[0].rapid_gossip_sync.update_network_graph_no_std(&initialization_input[..], Some(1642291930)).unwrap();
1567
1568                         // this should have added two channels and pruned the previous one.
1569                         assert_eq!($nodes[0].network_graph.read_only().channels().len(), 2);
1570
1571                         $receive.expect("Network graph not pruned within deadline");
1572
1573                         // all channels should now be pruned
1574                         assert_eq!($nodes[0].network_graph.read_only().channels().len(), 0);
1575                 }
1576         }
1577
1578         #[test]
1579         fn test_not_pruning_network_graph_until_graph_sync_completion() {
1580                 let (sender, receiver) = std::sync::mpsc::sync_channel(1);
1581
1582                 let (_, nodes) = create_nodes(2, "test_not_pruning_network_graph_until_graph_sync_completion");
1583                 let data_dir = nodes[0].persister.get_data_dir();
1584                 let persister = Arc::new(Persister::new(data_dir).with_graph_persistence_notifier(sender));
1585
1586                 let event_handler = |_: _| {};
1587                 let background_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].rapid_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
1588
1589                 do_test_not_pruning_network_graph_until_graph_sync_completion!(nodes,
1590                         receiver.recv_timeout(Duration::from_secs(super::FIRST_NETWORK_PRUNE_TIMER * 5)),
1591                         std::thread::sleep(Duration::from_millis(1)));
1592
1593                 background_processor.stop().unwrap();
1594         }
1595
1596         #[tokio::test]
1597         #[cfg(feature = "futures")]
1598         async fn test_not_pruning_network_graph_until_graph_sync_completion_async() {
1599                 let (sender, receiver) = std::sync::mpsc::sync_channel(1);
1600
1601                 let (_, nodes) = create_nodes(2, "test_not_pruning_network_graph_until_graph_sync_completion_async");
1602                 let data_dir = nodes[0].persister.get_data_dir();
1603                 let persister = Arc::new(Persister::new(data_dir).with_graph_persistence_notifier(sender));
1604
1605                 let (exit_sender, exit_receiver) = tokio::sync::watch::channel(());
1606                 let bp_future = super::process_events_async(
1607                         persister, |_: _| {async {}}, nodes[0].chain_monitor.clone(), nodes[0].node.clone(),
1608                         nodes[0].rapid_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(),
1609                         Some(nodes[0].scorer.clone()), move |dur: Duration| {
1610                                 let mut exit_receiver = exit_receiver.clone();
1611                                 Box::pin(async move {
1612                                         tokio::select! {
1613                                                 _ = tokio::time::sleep(dur) => false,
1614                                                 _ = exit_receiver.changed() => true,
1615                                         }
1616                                 })
1617                         }, false,
1618                 );
1619
1620                 let t1 = tokio::spawn(bp_future);
1621                 let t2 = tokio::spawn(async move {
1622                         do_test_not_pruning_network_graph_until_graph_sync_completion!(nodes, {
1623                                 let mut i = 0;
1624                                 loop {
1625                                         tokio::time::sleep(Duration::from_secs(super::FIRST_NETWORK_PRUNE_TIMER)).await;
1626                                         if let Ok(()) = receiver.try_recv() { break Ok::<(), ()>(()); }
1627                                         assert!(i < 5);
1628                                         i += 1;
1629                                 }
1630                         }, tokio::time::sleep(Duration::from_millis(1)).await);
1631                         exit_sender.send(()).unwrap();
1632                 });
1633                 let (r1, r2) = tokio::join!(t1, t2);
1634                 r1.unwrap().unwrap();
1635                 r2.unwrap()
1636         }
1637
1638         macro_rules! do_test_payment_path_scoring {
1639                 ($nodes: expr, $receive: expr) => {
1640                         // Ensure that we update the scorer when relevant events are processed. In this case, we ensure
1641                         // that we update the scorer upon a payment path succeeding (note that the channel must be
1642                         // public or else we won't score it).
1643                         // A background event handler for FundingGenerationReady events must be hooked up to a
1644                         // running background processor.
1645                         let scored_scid = 4242;
1646                         let secp_ctx = Secp256k1::new();
1647                         let node_1_privkey = SecretKey::from_slice(&[42; 32]).unwrap();
1648                         let node_1_id = PublicKey::from_secret_key(&secp_ctx, &node_1_privkey);
1649
1650                         let path = Path { hops: vec![RouteHop {
1651                                 pubkey: node_1_id,
1652                                 node_features: NodeFeatures::empty(),
1653                                 short_channel_id: scored_scid,
1654                                 channel_features: ChannelFeatures::empty(),
1655                                 fee_msat: 0,
1656                                 cltv_expiry_delta: MIN_CLTV_EXPIRY_DELTA as u32,
1657                         }], blinded_tail: None };
1658
1659                         $nodes[0].scorer.lock().unwrap().expect(TestResult::PaymentFailure { path: path.clone(), short_channel_id: scored_scid });
1660                         $nodes[0].node.push_pending_event(Event::PaymentPathFailed {
1661                                 payment_id: None,
1662                                 payment_hash: PaymentHash([42; 32]),
1663                                 payment_failed_permanently: false,
1664                                 failure: PathFailure::OnPath { network_update: None },
1665                                 path: path.clone(),
1666                                 short_channel_id: Some(scored_scid),
1667                         });
1668                         let event = $receive.expect("PaymentPathFailed not handled within deadline");
1669                         match event {
1670                                 Event::PaymentPathFailed { .. } => {},
1671                                 _ => panic!("Unexpected event"),
1672                         }
1673
1674                         // Ensure we'll score payments that were explicitly failed back by the destination as
1675                         // ProbeSuccess.
1676                         $nodes[0].scorer.lock().unwrap().expect(TestResult::ProbeSuccess { path: path.clone() });
1677                         $nodes[0].node.push_pending_event(Event::PaymentPathFailed {
1678                                 payment_id: None,
1679                                 payment_hash: PaymentHash([42; 32]),
1680                                 payment_failed_permanently: true,
1681                                 failure: PathFailure::OnPath { network_update: None },
1682                                 path: path.clone(),
1683                                 short_channel_id: None,
1684                         });
1685                         let event = $receive.expect("PaymentPathFailed not handled within deadline");
1686                         match event {
1687                                 Event::PaymentPathFailed { .. } => {},
1688                                 _ => panic!("Unexpected event"),
1689                         }
1690
1691                         $nodes[0].scorer.lock().unwrap().expect(TestResult::PaymentSuccess { path: path.clone() });
1692                         $nodes[0].node.push_pending_event(Event::PaymentPathSuccessful {
1693                                 payment_id: PaymentId([42; 32]),
1694                                 payment_hash: None,
1695                                 path: path.clone(),
1696                         });
1697                         let event = $receive.expect("PaymentPathSuccessful not handled within deadline");
1698                         match event {
1699                                 Event::PaymentPathSuccessful { .. } => {},
1700                                 _ => panic!("Unexpected event"),
1701                         }
1702
1703                         $nodes[0].scorer.lock().unwrap().expect(TestResult::ProbeSuccess { path: path.clone() });
1704                         $nodes[0].node.push_pending_event(Event::ProbeSuccessful {
1705                                 payment_id: PaymentId([42; 32]),
1706                                 payment_hash: PaymentHash([42; 32]),
1707                                 path: path.clone(),
1708                         });
1709                         let event = $receive.expect("ProbeSuccessful not handled within deadline");
1710                         match event {
1711                                 Event::ProbeSuccessful  { .. } => {},
1712                                 _ => panic!("Unexpected event"),
1713                         }
1714
1715                         $nodes[0].scorer.lock().unwrap().expect(TestResult::ProbeFailure { path: path.clone() });
1716                         $nodes[0].node.push_pending_event(Event::ProbeFailed {
1717                                 payment_id: PaymentId([42; 32]),
1718                                 payment_hash: PaymentHash([42; 32]),
1719                                 path,
1720                                 short_channel_id: Some(scored_scid),
1721                         });
1722                         let event = $receive.expect("ProbeFailure not handled within deadline");
1723                         match event {
1724                                 Event::ProbeFailed { .. } => {},
1725                                 _ => panic!("Unexpected event"),
1726                         }
1727                 }
1728         }
1729
1730         #[test]
1731         fn test_payment_path_scoring() {
1732                 let (sender, receiver) = std::sync::mpsc::sync_channel(1);
1733                 let event_handler = move |event: Event| match event {
1734                         Event::PaymentPathFailed { .. } => sender.send(event).unwrap(),
1735                         Event::PaymentPathSuccessful { .. } => sender.send(event).unwrap(),
1736                         Event::ProbeSuccessful { .. } => sender.send(event).unwrap(),
1737                         Event::ProbeFailed { .. } => sender.send(event).unwrap(),
1738                         _ => panic!("Unexpected event: {:?}", event),
1739                 };
1740
1741                 let (_, nodes) = create_nodes(1, "test_payment_path_scoring");
1742                 let data_dir = nodes[0].persister.get_data_dir();
1743                 let persister = Arc::new(Persister::new(data_dir));
1744                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].no_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
1745
1746                 do_test_payment_path_scoring!(nodes, receiver.recv_timeout(Duration::from_secs(EVENT_DEADLINE)));
1747
1748                 if !std::thread::panicking() {
1749                         bg_processor.stop().unwrap();
1750                 }
1751
1752                 let log_entries = nodes[0].logger.lines.lock().unwrap();
1753                 let expected_log = "Persisting scorer after update".to_string();
1754                 assert_eq!(*log_entries.get(&("lightning_background_processor".to_string(), expected_log)).unwrap(), 5);
1755         }
1756
1757         #[tokio::test]
1758         #[cfg(feature = "futures")]
1759         async fn test_payment_path_scoring_async() {
1760                 let (sender, mut receiver) = tokio::sync::mpsc::channel(1);
1761                 let event_handler = move |event: Event| {
1762                         let sender_ref = sender.clone();
1763                         async move {
1764                                 match event {
1765                                         Event::PaymentPathFailed { .. } => { sender_ref.send(event).await.unwrap() },
1766                                         Event::PaymentPathSuccessful { .. } => { sender_ref.send(event).await.unwrap() },
1767                                         Event::ProbeSuccessful { .. } => { sender_ref.send(event).await.unwrap() },
1768                                         Event::ProbeFailed { .. } => { sender_ref.send(event).await.unwrap() },
1769                                         _ => panic!("Unexpected event: {:?}", event),
1770                                 }
1771                         }
1772                 };
1773
1774                 let (_, nodes) = create_nodes(1, "test_payment_path_scoring_async");
1775                 let data_dir = nodes[0].persister.get_data_dir();
1776                 let persister = Arc::new(Persister::new(data_dir));
1777
1778                 let (exit_sender, exit_receiver) = tokio::sync::watch::channel(());
1779
1780                 let bp_future = super::process_events_async(
1781                         persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(),
1782                         nodes[0].no_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(),
1783                         Some(nodes[0].scorer.clone()), move |dur: Duration| {
1784                                 let mut exit_receiver = exit_receiver.clone();
1785                                 Box::pin(async move {
1786                                         tokio::select! {
1787                                                 _ = tokio::time::sleep(dur) => false,
1788                                                 _ = exit_receiver.changed() => true,
1789                                         }
1790                                 })
1791                         }, false,
1792                 );
1793                 let t1 = tokio::spawn(bp_future);
1794                 let t2 = tokio::spawn(async move {
1795                         do_test_payment_path_scoring!(nodes, receiver.recv().await);
1796                         exit_sender.send(()).unwrap();
1797
1798                         let log_entries = nodes[0].logger.lines.lock().unwrap();
1799                         let expected_log = "Persisting scorer after update".to_string();
1800                         assert_eq!(*log_entries.get(&("lightning_background_processor".to_string(), expected_log)).unwrap(), 5);
1801                 });
1802
1803                 let (r1, r2) = tokio::join!(t1, t2);
1804                 r1.unwrap().unwrap();
1805                 r2.unwrap()
1806         }
1807 }