_ 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 #![deny(broken_intra_doc_links)]
   6 #![deny(missing_docs)]
   7 #![deny(unsafe_code)]
   8
   9 #![cfg_attr(docsrs, feature(doc_auto_cfg))]
  10
  11 #[macro_use] extern crate lightning;
  12
  13 use lightning::chain;
  14 use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
  15 use lightning::chain::chainmonitor::{ChainMonitor, Persist};
  16 use lightning::chain::keysinterface::{Sign, KeysInterface};
  17 use lightning::ln::channelmanager::ChannelManager;
  18 use lightning::ln::msgs::{ChannelMessageHandler, RoutingMessageHandler};
  19 use lightning::ln::peer_handler::{CustomMessageHandler, PeerManager, SocketDescriptor};
  20 use lightning::routing::network_graph::{NetworkGraph, NetGraphMsgHandler};
  21 use lightning::routing::scoring::WriteableScore;
  22 use lightning::util::events::{Event, EventHandler, EventsProvider};
  23 use lightning::util::logger::Logger;
  24 use lightning::util::persist::Persister;
  25 use std::sync::Arc;
  26 use std::sync::atomic::{AtomicBool, Ordering};
  27 use std::thread;
  28 use std::thread::JoinHandle;
  29 use std::time::{Duration, Instant};
  30 use std::ops::Deref;
  31
  32 /// `BackgroundProcessor` takes care of tasks that (1) need to happen periodically to keep
  33 /// Rust-Lightning running properly, and (2) either can or should be run in the background. Its
  34 /// responsibilities are:
  35 /// * Processing [`Event`]s with a user-provided [`EventHandler`].
  36 /// * Monitoring whether the [`ChannelManager`] needs to be re-persisted to disk, and if so,
  37 ///   writing it to disk/backups by invoking the callback given to it at startup.
  38 ///   [`ChannelManager`] persistence should be done in the background.
  39 /// * Calling [`ChannelManager::timer_tick_occurred`] and [`PeerManager::timer_tick_occurred`]
  40 ///   at the appropriate intervals.
  41 /// * Calling [`NetworkGraph::remove_stale_channels`] (if a [`NetGraphMsgHandler`] is provided to
  42 ///   [`BackgroundProcessor::start`]).
  43 ///
  44 /// It will also call [`PeerManager::process_events`] periodically though this shouldn't be relied
  45 /// upon as doing so may result in high latency.
  46 ///
  47 /// # Note
  48 ///
  49 /// If [`ChannelManager`] persistence fails and the persisted manager becomes out-of-date, then
  50 /// there is a risk of channels force-closing on startup when the manager realizes it's outdated.
  51 /// However, as long as [`ChannelMonitor`] backups are sound, no funds besides those used for
  52 /// unilateral chain closure fees are at risk.
  53 ///
  54 /// [`ChannelMonitor`]: lightning::chain::channelmonitor::ChannelMonitor
  55 /// [`Event`]: lightning::util::events::Event
  56 #[must_use = "BackgroundProcessor will immediately stop on drop. It should be stored until shutdown."]
  57 pub struct BackgroundProcessor {
  58         stop_thread: Arc<AtomicBool>,
  59         thread_handle: Option<JoinHandle<Result<(), std::io::Error>>>,
  60 }
  61
  62 #[cfg(not(test))]
  63 const FRESHNESS_TIMER: u64 = 60;
  64 #[cfg(test)]
  65 const FRESHNESS_TIMER: u64 = 1;
  66
  67 #[cfg(all(not(test), not(debug_assertions)))]
  68 const PING_TIMER: u64 = 10;
  69 /// Signature operations take a lot longer without compiler optimisations.
  70 /// Increasing the ping timer allows for this but slower devices will be disconnected if the
  71 /// timeout is reached.
  72 #[cfg(all(not(test), debug_assertions))]
  73 const PING_TIMER: u64 = 30;
  74 #[cfg(test)]
  75 const PING_TIMER: u64 = 1;
  76
  77 /// Prune the network graph of stale entries hourly.
  78 const NETWORK_PRUNE_TIMER: u64 = 60 * 60;
  79
  80 #[cfg(not(test))]
  81 const FIRST_NETWORK_PRUNE_TIMER: u64 = 60;
  82 #[cfg(test)]
  83 const FIRST_NETWORK_PRUNE_TIMER: u64 = 1;
  84
  85
  86 /// Decorates an [`EventHandler`] with common functionality provided by standard [`EventHandler`]s.
  87 struct DecoratingEventHandler<
  88         E: EventHandler,
  89         N: Deref<Target = NetGraphMsgHandler<G, A, L>>,
  90         G: Deref<Target = NetworkGraph>,
  91         A: Deref,
  92         L: Deref,
  93 >
  94 where A::Target: chain::Access, L::Target: Logger {
  95         event_handler: E,
  96         net_graph_msg_handler: Option<N>,
  97 }
  98
  99 impl<
 100         E: EventHandler,
 101         N: Deref<Target = NetGraphMsgHandler<G, A, L>>,
 102         G: Deref<Target = NetworkGraph>,
 103         A: Deref,
 104         L: Deref,
 105 > EventHandler for DecoratingEventHandler<E, N, G, A, L>
 106 where A::Target: chain::Access, L::Target: Logger {
 107         fn handle_event(&self, event: &Event) {
 108                 if let Some(event_handler) = &self.net_graph_msg_handler {
 109                         event_handler.handle_event(event);
 110                 }
 111                 self.event_handler.handle_event(event);
 112         }
 113 }
 114
 115 impl BackgroundProcessor {
 116         /// Start a background thread that takes care of responsibilities enumerated in the [top-level
 117         /// documentation].
 118         ///
 119         /// The thread runs indefinitely unless the object is dropped, [`stop`] is called, or
 120         /// [`Persister::persist_manager`] returns an error. In case of an error, the error is retrieved by calling
 121         /// either [`join`] or [`stop`].
 122         ///
 123         /// # Data Persistence
 124         ///
 125         /// [`Persister::persist_manager`] is responsible for writing out the [`ChannelManager`] to disk, and/or
 126         /// uploading to one or more backup services. See [`ChannelManager::write`] for writing out a
 127         /// [`ChannelManager`]. See the `lightning-persister` crate for LDK's
 128         /// provided implementation.
 129         ///
 130         /// [`Persister::persist_graph`] is responsible for writing out the [`NetworkGraph`] to disk. See
 131         /// [`NetworkGraph::write`] for writing out a [`NetworkGraph`]. See the `lightning-persister` crate
 132         /// for LDK's provided implementation.
 133         ///
 134         /// Typically, users should either implement [`Persister::persist_manager`] to never return an
 135         /// error or call [`join`] and handle any error that may arise. For the latter case,
 136         /// `BackgroundProcessor` must be restarted by calling `start` again after handling the error.
 137         ///
 138         /// # Event Handling
 139         ///
 140         /// `event_handler` is responsible for handling events that users should be notified of (e.g.,
 141         /// payment failed). [`BackgroundProcessor`] may decorate the given [`EventHandler`] with common
 142         /// functionality implemented by other handlers.
 143         /// * [`NetGraphMsgHandler`] if given will update the [`NetworkGraph`] based on payment failures.
 144         ///
 145         /// [top-level documentation]: BackgroundProcessor
 146         /// [`join`]: Self::join
 147         /// [`stop`]: Self::stop
 148         /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
 149         /// [`ChannelManager::write`]: lightning::ln::channelmanager::ChannelManager#impl-Writeable
 150         /// [`Persister::persist_manager`]: lightning::util::persist::Persister::persist_manager
 151         /// [`Persister::persist_graph`]: lightning::util::persist::Persister::persist_graph
 152         /// [`NetworkGraph`]: lightning::routing::network_graph::NetworkGraph
 153         /// [`NetworkGraph::write`]: lightning::routing::network_graph::NetworkGraph#impl-Writeable
 154         pub fn start<
 155                 'a,
 156                 Signer: 'static + Sign,
 157                 CA: 'static + Deref + Send + Sync,
 158                 CF: 'static + Deref + Send + Sync,
 159                 CW: 'static + Deref + Send + Sync,
 160                 T: 'static + Deref + Send + Sync,
 161                 K: 'static + Deref + Send + Sync,
 162                 F: 'static + Deref + Send + Sync,
 163                 G: 'static + Deref<Target = NetworkGraph> + Send + Sync,
 164                 L: 'static + Deref + Send + Sync,
 165                 P: 'static + Deref + Send + Sync,
 166                 Descriptor: 'static + SocketDescriptor + Send + Sync,
 167                 CMH: 'static + Deref + Send + Sync,
 168                 RMH: 'static + Deref + Send + Sync,
 169                 EH: 'static + EventHandler + Send,
 170                 PS: 'static + Deref + Send,
 171                 M: 'static + Deref<Target = ChainMonitor<Signer, CF, T, F, L, P>> + Send + Sync,
 172                 CM: 'static + Deref<Target = ChannelManager<Signer, CW, T, K, F, L>> + Send + Sync,
 173                 NG: 'static + Deref<Target = NetGraphMsgHandler<G, CA, L>> + Send + Sync,
 174                 UMH: 'static + Deref + Send + Sync,
 175                 PM: 'static + Deref<Target = PeerManager<Descriptor, CMH, RMH, L, UMH>> + Send + Sync,
 176                 S: 'static + Deref<Target = SC> + Send + Sync,
 177                 SC: WriteableScore<'a>,
 178         >(
 179                 persister: PS, event_handler: EH, chain_monitor: M, channel_manager: CM,
 180                 net_graph_msg_handler: Option<NG>, peer_manager: PM, logger: L, scorer: Option<S>
 181         ) -> Self
 182         where
 183                 CA::Target: 'static + chain::Access,
 184                 CF::Target: 'static + chain::Filter,
 185                 CW::Target: 'static + chain::Watch<Signer>,
 186                 T::Target: 'static + BroadcasterInterface,
 187                 K::Target: 'static + KeysInterface<Signer = Signer>,
 188                 F::Target: 'static + FeeEstimator,
 189                 L::Target: 'static + Logger,
 190                 P::Target: 'static + Persist<Signer>,
 191                 CMH::Target: 'static + ChannelMessageHandler,
 192                 RMH::Target: 'static + RoutingMessageHandler,
 193                 UMH::Target: 'static + CustomMessageHandler,
 194                 PS::Target: 'static + Persister<'a, Signer, CW, T, K, F, L, SC>,
 195         {
 196                 let stop_thread = Arc::new(AtomicBool::new(false));
 197                 let stop_thread_clone = stop_thread.clone();
 198                 let handle = thread::spawn(move || -> Result<(), std::io::Error> {
 199                         let event_handler = DecoratingEventHandler { event_handler, net_graph_msg_handler: net_graph_msg_handler.as_ref().map(|t| t.deref()) };
 200
 201                         log_trace!(logger, "Calling ChannelManager's timer_tick_occurred on startup");
 202                         channel_manager.timer_tick_occurred();
 203
 204                         let mut last_freshness_call = Instant::now();
 205                         let mut last_ping_call = Instant::now();
 206                         let mut last_prune_call = Instant::now();
 207                         let mut have_pruned = false;
 208
 209                         loop {
 210                                 channel_manager.process_pending_events(&event_handler);
 211                                 chain_monitor.process_pending_events(&event_handler);
 212
 213                                 // Note that the PeerManager::process_events may block on ChannelManager's locks,
 214                                 // hence it comes last here. When the ChannelManager finishes whatever it's doing,
 215                                 // we want to ensure we get into `persist_manager` as quickly as we can, especially
 216                                 // without running the normal event processing above and handing events to users.
 217                                 //
 218                                 // Specifically, on an *extremely* slow machine, we may see ChannelManager start
 219                                 // processing a message effectively at any point during this loop. In order to
 220                                 // minimize the time between such processing completing and persisting the updated
 221                                 // ChannelManager, we want to minimize methods blocking on a ChannelManager
 222                                 // generally, and as a fallback place such blocking only immediately before
 223                                 // persistence.
 224                                 peer_manager.process_events();
 225
 226                                 // We wait up to 100ms, but track how long it takes to detect being put to sleep,
 227                                 // see `await_start`'s use below.
 228                                 let await_start = Instant::now();
 229                                 let updates_available =
 230                                         channel_manager.await_persistable_update_timeout(Duration::from_millis(100));
 231                                 let await_time = await_start.elapsed();
 232
 233                                 if updates_available {
 234                                         log_trace!(logger, "Persisting ChannelManager...");
 235                                         persister.persist_manager(&*channel_manager)?;
 236                                         log_trace!(logger, "Done persisting ChannelManager.");
 237                                 }
 238                                 // Exit the loop if the background processor was requested to stop.
 239                                 if stop_thread.load(Ordering::Acquire) == true {
 240                                         log_trace!(logger, "Terminating background processor.");
 241                                         break;
 242                                 }
 243                                 if last_freshness_call.elapsed().as_secs() > FRESHNESS_TIMER {
 244                                         log_trace!(logger, "Calling ChannelManager's timer_tick_occurred");
 245                                         channel_manager.timer_tick_occurred();
 246                                         last_freshness_call = Instant::now();
 247                                 }
 248                                 if await_time > Duration::from_secs(1) {
 249                                         // On various platforms, we may be starved of CPU cycles for several reasons.
 250                                         // E.g. on iOS, if we've been in the background, we will be entirely paused.
 251                                         // Similarly, if we're on a desktop platform and the device has been asleep, we
 252                                         // may not get any cycles.
 253                                         // We detect this by checking if our max-100ms-sleep, above, ran longer than a
 254                                         // full second, at which point we assume sockets may have been killed (they
 255                                         // appear to be at least on some platforms, even if it has only been a second).
 256                                         // Note that we have to take care to not get here just because user event
 257                                         // processing was slow at the top of the loop. For example, the sample client
 258                                         // may call Bitcoin Core RPCs during event handling, which very often takes
 259                                         // more than a handful of seconds to complete, and shouldn't disconnect all our
 260                                         // peers.
 261                                         log_trace!(logger, "100ms sleep took more than a second, disconnecting peers.");
 262                                         peer_manager.disconnect_all_peers();
 263                                         last_ping_call = Instant::now();
 264                                 } else if last_ping_call.elapsed().as_secs() > PING_TIMER {
 265                                         log_trace!(logger, "Calling PeerManager's timer_tick_occurred");
 266                                         peer_manager.timer_tick_occurred();
 267                                         last_ping_call = Instant::now();
 268                                 }
 269
 270                                 // Note that we want to run a graph prune once not long after startup before
 271                                 // falling back to our usual hourly prunes. This avoids short-lived clients never
 272                                 // pruning their network graph. We run once 60 seconds after startup before
 273                                 // continuing our normal cadence.
 274                                 if last_prune_call.elapsed().as_secs() > if have_pruned { NETWORK_PRUNE_TIMER } else { FIRST_NETWORK_PRUNE_TIMER } {
 275                                         if let Some(ref handler) = net_graph_msg_handler {
 276                                                 log_trace!(logger, "Pruning network graph of stale entries");
 277                                                 handler.network_graph().remove_stale_channels();
 278                                                 if let Err(e) = persister.persist_graph(handler.network_graph()) {
 279                                                         log_error!(logger, "Error: Failed to persist network graph, check your disk and permissions {}", e)
 280                                                 }
 281                                                 last_prune_call = Instant::now();
 282                                                 have_pruned = true;
 283                                         }
 284                                         if let Some(ref scorer) = scorer {
 285                                                 log_trace!(logger, "Persisting scorer");
 286                                                 if let Err(e) = persister.persist_scorer(&scorer) {
 287                                                         log_error!(logger, "Error: Failed to persist scorer, check your disk and permissions {}", e)
 288                                                 }
 289                                         }
 290                                 }
 291                         }
 292
 293                         // After we exit, ensure we persist the ChannelManager one final time - this avoids
 294                         // some races where users quit while channel updates were in-flight, with
 295                         // ChannelMonitor update(s) persisted without a corresponding ChannelManager update.
 296                         persister.persist_manager(&*channel_manager)?;
 297
 298                         // Persist Scorer on exit
 299                         if let Some(ref scorer) = scorer {
 300                                 persister.persist_scorer(&scorer)?;
 301                         }
 302
 303                         // Persist NetworkGraph on exit
 304                         if let Some(ref handler) = net_graph_msg_handler {
 305                                 persister.persist_graph(handler.network_graph())?;
 306                         }
 307
 308                         Ok(())
 309                 });
 310                 Self { stop_thread: stop_thread_clone, thread_handle: Some(handle) }
 311         }
 312
 313         /// Join `BackgroundProcessor`'s thread, returning any error that occurred while persisting
 314         /// [`ChannelManager`].
 315         ///
 316         /// # Panics
 317         ///
 318         /// This function panics if the background thread has panicked such as while persisting or
 319         /// handling events.
 320         ///
 321         /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
 322         pub fn join(mut self) -> Result<(), std::io::Error> {
 323                 assert!(self.thread_handle.is_some());
 324                 self.join_thread()
 325         }
 326
 327         /// Stop `BackgroundProcessor`'s thread, returning any error that occurred while persisting
 328         /// [`ChannelManager`].
 329         ///
 330         /// # Panics
 331         ///
 332         /// This function panics if the background thread has panicked such as while persisting or
 333         /// handling events.
 334         ///
 335         /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
 336         pub fn stop(mut self) -> Result<(), std::io::Error> {
 337                 assert!(self.thread_handle.is_some());
 338                 self.stop_and_join_thread()
 339         }
 340
 341         fn stop_and_join_thread(&mut self) -> Result<(), std::io::Error> {
 342                 self.stop_thread.store(true, Ordering::Release);
 343                 self.join_thread()
 344         }
 345
 346         fn join_thread(&mut self) -> Result<(), std::io::Error> {
 347                 match self.thread_handle.take() {
 348                         Some(handle) => handle.join().unwrap(),
 349                         None => Ok(()),
 350                 }
 351         }
 352 }
 353
 354 impl Drop for BackgroundProcessor {
 355         fn drop(&mut self) {
 356                 self.stop_and_join_thread().unwrap();
 357         }
 358 }
 359
 360 #[cfg(test)]
 361 mod tests {
 362         use bitcoin::blockdata::block::BlockHeader;
 363         use bitcoin::blockdata::constants::genesis_block;
 364         use bitcoin::blockdata::transaction::{Transaction, TxOut};
 365         use bitcoin::network::constants::Network;
 366         use lightning::chain::{BestBlock, Confirm, chainmonitor};
 367         use lightning::chain::channelmonitor::ANTI_REORG_DELAY;
 368         use lightning::chain::keysinterface::{InMemorySigner, Recipient, KeysInterface, KeysManager};
 369         use lightning::chain::transaction::OutPoint;
 370         use lightning::get_event_msg;
 371         use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, ChannelManager, SimpleArcChannelManager};
 372         use lightning::ln::features::InitFeatures;
 373         use lightning::ln::msgs::{ChannelMessageHandler, Init};
 374         use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler};
 375         use lightning::routing::network_graph::{NetworkGraph, NetGraphMsgHandler};
 376         use lightning::util::config::UserConfig;
 377         use lightning::util::events::{Event, MessageSendEventsProvider, MessageSendEvent};
 378         use lightning::util::ser::Writeable;
 379         use lightning::util::test_utils;
 380         use lightning::util::persist::KVStorePersister;
 381         use lightning_invoice::payment::{InvoicePayer, RetryAttempts};
 382         use lightning_invoice::utils::DefaultRouter;
 383         use lightning_persister::FilesystemPersister;
 384         use std::fs;
 385         use std::path::PathBuf;
 386         use std::sync::{Arc, Mutex};
 387         use std::time::Duration;
 388         use lightning::routing::scoring::{FixedPenaltyScorer};
 389         use super::{BackgroundProcessor, FRESHNESS_TIMER};
 390
 391         const EVENT_DEADLINE: u64 = 5 * FRESHNESS_TIMER;
 392
 393         #[derive(Clone, Eq, Hash, PartialEq)]
 394         struct TestDescriptor{}
 395         impl SocketDescriptor for TestDescriptor {
 396                 fn send_data(&mut self, _data: &[u8], _resume_read: bool) -> usize {
 397                         0
 398                 }
 399
 400                 fn disconnect_socket(&mut self) {}
 401         }
 402
 403         type ChainMonitor = chainmonitor::ChainMonitor<InMemorySigner, Arc<test_utils::TestChainSource>, Arc<test_utils::TestBroadcaster>, Arc<test_utils::TestFeeEstimator>, Arc<test_utils::TestLogger>, Arc<FilesystemPersister>>;
 404
 405         struct Node {
 406                 node: Arc<SimpleArcChannelManager<ChainMonitor, test_utils::TestBroadcaster, test_utils::TestFeeEstimator, test_utils::TestLogger>>,
 407                 net_graph_msg_handler: Option<Arc<NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>>>,
 408                 peer_manager: Arc<PeerManager<TestDescriptor, Arc<test_utils::TestChannelMessageHandler>, Arc<test_utils::TestRoutingMessageHandler>, Arc<test_utils::TestLogger>, IgnoringMessageHandler>>,
 409                 chain_monitor: Arc<ChainMonitor>,
 410                 persister: Arc<FilesystemPersister>,
 411                 tx_broadcaster: Arc<test_utils::TestBroadcaster>,
 412                 network_graph: Arc<NetworkGraph>,
 413                 logger: Arc<test_utils::TestLogger>,
 414                 best_block: BestBlock,
 415                 scorer: Arc<Mutex<FixedPenaltyScorer>>,
 416         }
 417
 418         impl Drop for Node {
 419                 fn drop(&mut self) {
 420                         let data_dir = self.persister.get_data_dir();
 421                         match fs::remove_dir_all(data_dir.clone()) {
 422                                 Err(e) => println!("Failed to remove test persister directory {}: {}", data_dir, e),
 423                                 _ => {}
 424                         }
 425                 }
 426         }
 427
 428         struct Persister {
 429                 graph_error: Option<(std::io::ErrorKind, &'static str)>,
 430                 manager_error: Option<(std::io::ErrorKind, &'static str)>,
 431                 scorer_error: Option<(std::io::ErrorKind, &'static str)>,
 432                 filesystem_persister: FilesystemPersister,
 433         }
 434
 435         impl Persister {
 436                 fn new(data_dir: String) -> Self {
 437                         let filesystem_persister = FilesystemPersister::new(data_dir.clone());
 438                         Self { graph_error: None, manager_error: None, scorer_error: None, filesystem_persister }
 439                 }
 440
 441                 fn with_graph_error(self, error: std::io::ErrorKind, message: &'static str) -> Self {
 442                         Self { graph_error: Some((error, message)), ..self }
 443                 }
 444
 445                 fn with_manager_error(self, error: std::io::ErrorKind, message: &'static str) -> Self {
 446                         Self { manager_error: Some((error, message)), ..self }
 447                 }
 448
 449                 fn with_scorer_error(self, error: std::io::ErrorKind, message: &'static str) -> Self {
 450                         Self { scorer_error: Some((error, message)), ..self }
 451                 }
 452         }
 453
 454         impl KVStorePersister for Persister {
 455                 fn persist<W: Writeable>(&self, key: &str, object: &W) -> std::io::Result<()> {
 456                         if key == "manager" {
 457                                 if let Some((error, message)) = self.manager_error {
 458                                         return Err(std::io::Error::new(error, message))
 459                                 }
 460                         }
 461
 462                         if key == "network_graph" {
 463                                 if let Some((error, message)) = self.graph_error {
 464                                         return Err(std::io::Error::new(error, message))
 465                                 }
 466                         }
 467
 468                         if key == "scorer" {
 469                                 if let Some((error, message)) = self.scorer_error {
 470                                         return Err(std::io::Error::new(error, message))
 471                                 }
 472                         }
 473
 474                         self.filesystem_persister.persist(key, object)
 475                 }
 476         }
 477
 478         fn get_full_filepath(filepath: String, filename: String) -> String {
 479                 let mut path = PathBuf::from(filepath);
 480                 path.push(filename);
 481                 path.to_str().unwrap().to_string()
 482         }
 483
 484         fn create_nodes(num_nodes: usize, persist_dir: String) -> Vec<Node> {
 485                 let mut nodes = Vec::new();
 486                 for i in 0..num_nodes {
 487                         let tx_broadcaster = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new()), blocks: Arc::new(Mutex::new(Vec::new()))});
 488                         let fee_estimator = Arc::new(test_utils::TestFeeEstimator { sat_per_kw: Mutex::new(253) });
 489                         let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
 490                         let logger = Arc::new(test_utils::TestLogger::with_id(format!("node {}", i)));
 491                         let persister = Arc::new(FilesystemPersister::new(format!("{}_persister_{}", persist_dir, i)));
 492                         let seed = [i as u8; 32];
 493                         let network = Network::Testnet;
 494                         let genesis_block = genesis_block(network);
 495                         let now = Duration::from_secs(genesis_block.header.time as u64);
 496                         let keys_manager = Arc::new(KeysManager::new(&seed, now.as_secs(), now.subsec_nanos()));
 497                         let chain_monitor = Arc::new(chainmonitor::ChainMonitor::new(Some(chain_source.clone()), tx_broadcaster.clone(), logger.clone(), fee_estimator.clone(), persister.clone()));
 498                         let best_block = BestBlock::from_genesis(network);
 499                         let params = ChainParameters { network, best_block };
 500                         let manager = Arc::new(ChannelManager::new(fee_estimator.clone(), chain_monitor.clone(), tx_broadcaster.clone(), logger.clone(), keys_manager.clone(), UserConfig::default(), params));
 501                         let network_graph = Arc::new(NetworkGraph::new(genesis_block.header.block_hash()));
 502                         let net_graph_msg_handler = Some(Arc::new(NetGraphMsgHandler::new(network_graph.clone(), Some(chain_source.clone()), logger.clone())));
 503                         let msg_handler = MessageHandler { chan_handler: Arc::new(test_utils::TestChannelMessageHandler::new()), route_handler: Arc::new(test_utils::TestRoutingMessageHandler::new() )};
 504                         let peer_manager = Arc::new(PeerManager::new(msg_handler, keys_manager.get_node_secret(Recipient::Node).unwrap(), &seed, logger.clone(), IgnoringMessageHandler{}));
 505                         let scorer = Arc::new(Mutex::new(test_utils::TestScorer::with_penalty(0)));
 506                         let node = Node { node: manager, net_graph_msg_handler, peer_manager, chain_monitor, persister, tx_broadcaster, network_graph, logger, best_block, scorer };
 507                         nodes.push(node);
 508                 }
 509
 510                 for i in 0..num_nodes {
 511                         for j in (i+1)..num_nodes {
 512                                 nodes[i].node.peer_connected(&nodes[j].node.get_our_node_id(), &Init { features: InitFeatures::known(), remote_network_address: None });
 513                                 nodes[j].node.peer_connected(&nodes[i].node.get_our_node_id(), &Init { features: InitFeatures::known(), remote_network_address: None });
 514                         }
 515                 }
 516
 517                 nodes
 518         }
 519
 520         macro_rules! open_channel {
 521                 ($node_a: expr, $node_b: expr, $channel_value: expr) => {{
 522                         begin_open_channel!($node_a, $node_b, $channel_value);
 523                         let events = $node_a.node.get_and_clear_pending_events();
 524                         assert_eq!(events.len(), 1);
 525                         let (temporary_channel_id, tx) = handle_funding_generation_ready!(&events[0], $channel_value);
 526                         end_open_channel!($node_a, $node_b, temporary_channel_id, tx);
 527                         tx
 528                 }}
 529         }
 530
 531         macro_rules! begin_open_channel {
 532                 ($node_a: expr, $node_b: expr, $channel_value: expr) => {{
 533                         $node_a.node.create_channel($node_b.node.get_our_node_id(), $channel_value, 100, 42, None).unwrap();
 534                         $node_b.node.handle_open_channel(&$node_a.node.get_our_node_id(), InitFeatures::known(), &get_event_msg!($node_a, MessageSendEvent::SendOpenChannel, $node_b.node.get_our_node_id()));
 535                         $node_a.node.handle_accept_channel(&$node_b.node.get_our_node_id(), InitFeatures::known(), &get_event_msg!($node_b, MessageSendEvent::SendAcceptChannel, $node_a.node.get_our_node_id()));
 536                 }}
 537         }
 538
 539         macro_rules! handle_funding_generation_ready {
 540                 ($event: expr, $channel_value: expr) => {{
 541                         match $event {
 542                                 &Event::FundingGenerationReady { temporary_channel_id, channel_value_satoshis, ref output_script, user_channel_id } => {
 543                                         assert_eq!(channel_value_satoshis, $channel_value);
 544                                         assert_eq!(user_channel_id, 42);
 545
 546                                         let tx = Transaction { version: 1 as i32, lock_time: 0, input: Vec::new(), output: vec![TxOut {
 547                                                 value: channel_value_satoshis, script_pubkey: output_script.clone(),
 548                                         }]};
 549                                         (temporary_channel_id, tx)
 550                                 },
 551                                 _ => panic!("Unexpected event"),
 552                         }
 553                 }}
 554         }
 555
 556         macro_rules! end_open_channel {
 557                 ($node_a: expr, $node_b: expr, $temporary_channel_id: expr, $tx: expr) => {{
 558                         $node_a.node.funding_transaction_generated(&$temporary_channel_id, $tx.clone()).unwrap();
 559                         $node_b.node.handle_funding_created(&$node_a.node.get_our_node_id(), &get_event_msg!($node_a, MessageSendEvent::SendFundingCreated, $node_b.node.get_our_node_id()));
 560                         $node_a.node.handle_funding_signed(&$node_b.node.get_our_node_id(), &get_event_msg!($node_b, MessageSendEvent::SendFundingSigned, $node_a.node.get_our_node_id()));
 561                 }}
 562         }
 563
 564         fn confirm_transaction_depth(node: &mut Node, tx: &Transaction, depth: u32) {
 565                 for i in 1..=depth {
 566                         let prev_blockhash = node.best_block.block_hash();
 567                         let height = node.best_block.height() + 1;
 568                         let header = BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: Default::default(), time: height, bits: 42, nonce: 42 };
 569                         let txdata = vec![(0, tx)];
 570                         node.best_block = BestBlock::new(header.block_hash(), height);
 571                         match i {
 572                                 1 => {
 573                                         node.node.transactions_confirmed(&header, &txdata, height);
 574                                         node.chain_monitor.transactions_confirmed(&header, &txdata, height);
 575                                 },
 576                                 x if x == depth => {
 577                                         node.node.best_block_updated(&header, height);
 578                                         node.chain_monitor.best_block_updated(&header, height);
 579                                 },
 580                                 _ => {},
 581                         }
 582                 }
 583         }
 584         fn confirm_transaction(node: &mut Node, tx: &Transaction) {
 585                 confirm_transaction_depth(node, tx, ANTI_REORG_DELAY);
 586         }
 587
 588         #[test]
 589         fn test_background_processor() {
 590                 // Test that when a new channel is created, the ChannelManager needs to be re-persisted with
 591                 // updates. Also test that when new updates are available, the manager signals that it needs
 592                 // re-persistence and is successfully re-persisted.
 593                 let nodes = create_nodes(2, "test_background_processor".to_string());
 594
 595                 // Go through the channel creation process so that each node has something to persist. Since
 596                 // open_channel consumes events, it must complete before starting BackgroundProcessor to
 597                 // avoid a race with processing events.
 598                 let tx = open_channel!(nodes[0], nodes[1], 100000);
 599
 600                 // Initiate the background processors to watch each node.
 601                 let data_dir = nodes[0].persister.get_data_dir();
 602                 let persister = Arc::new(Persister::new(data_dir));
 603                 let event_handler = |_: &_| {};
 604                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].net_graph_msg_handler.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
 605
 606                 macro_rules! check_persisted_data {
 607                         ($node: expr, $filepath: expr) => {
 608                                 let mut expected_bytes = Vec::new();
 609                                 loop {
 610                                         expected_bytes.clear();
 611                                         match $node.write(&mut expected_bytes) {
 612                                                 Ok(()) => {
 613                                                         match std::fs::read($filepath) {
 614                                                                 Ok(bytes) => {
 615                                                                         if bytes == expected_bytes {
 616                                                                                 break
 617                                                                         } else {
 618                                                                                 continue
 619                                                                         }
 620                                                                 },
 621                                                                 Err(_) => continue
 622                                                         }
 623                                                 },
 624                                                 Err(e) => panic!("Unexpected error: {}", e)
 625                                         }
 626                                 }
 627                         }
 628                 }
 629
 630                 // Check that the initial channel manager data is persisted as expected.
 631                 let filepath = get_full_filepath("test_background_processor_persister_0".to_string(), "manager".to_string());
 632                 check_persisted_data!(nodes[0].node, filepath.clone());
 633
 634                 loop {
 635                         if !nodes[0].node.get_persistence_condvar_value() { break }
 636                 }
 637
 638                 // Force-close the channel.
 639                 nodes[0].node.force_close_channel(&OutPoint { txid: tx.txid(), index: 0 }.to_channel_id()).unwrap();
 640
 641                 // Check that the force-close updates are persisted.
 642                 check_persisted_data!(nodes[0].node, filepath.clone());
 643                 loop {
 644                         if !nodes[0].node.get_persistence_condvar_value() { break }
 645                 }
 646
 647                 // Check network graph is persisted
 648                 let filepath = get_full_filepath("test_background_processor_persister_0".to_string(), "network_graph".to_string());
 649                 if let Some(ref handler) = nodes[0].net_graph_msg_handler {
 650                         let network_graph = handler.network_graph();
 651                         check_persisted_data!(network_graph, filepath.clone());
 652                 }
 653
 654                 // Check scorer is persisted
 655                 let filepath = get_full_filepath("test_background_processor_persister_0".to_string(), "scorer".to_string());
 656                 check_persisted_data!(nodes[0].scorer, filepath.clone());
 657
 658                 assert!(bg_processor.stop().is_ok());
 659         }
 660
 661         #[test]
 662         fn test_timer_tick_called() {
 663                 // Test that ChannelManager's and PeerManager's `timer_tick_occurred` is called every
 664                 // `FRESHNESS_TIMER`.
 665                 let nodes = create_nodes(1, "test_timer_tick_called".to_string());
 666                 let data_dir = nodes[0].persister.get_data_dir();
 667                 let persister = Arc::new(Persister::new(data_dir));
 668                 let event_handler = |_: &_| {};
 669                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].net_graph_msg_handler.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
 670                 loop {
 671                         let log_entries = nodes[0].logger.lines.lock().unwrap();
 672                         let desired_log = "Calling ChannelManager's timer_tick_occurred".to_string();
 673                         let second_desired_log = "Calling PeerManager's timer_tick_occurred".to_string();
 674                         if log_entries.get(&("lightning_background_processor".to_string(), desired_log)).is_some() &&
 675                                         log_entries.get(&("lightning_background_processor".to_string(), second_desired_log)).is_some() {
 676                                 break
 677                         }
 678                 }
 679
 680                 assert!(bg_processor.stop().is_ok());
 681         }
 682
 683         #[test]
 684         fn test_channel_manager_persist_error() {
 685                 // Test that if we encounter an error during manager persistence, the thread panics.
 686                 let nodes = create_nodes(2, "test_persist_error".to_string());
 687                 open_channel!(nodes[0], nodes[1], 100000);
 688
 689                 let data_dir = nodes[0].persister.get_data_dir();
 690                 let persister = Arc::new(Persister::new(data_dir).with_manager_error(std::io::ErrorKind::Other, "test"));
 691                 let event_handler = |_: &_| {};
 692                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].net_graph_msg_handler.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
 693                 match bg_processor.join() {
 694                         Ok(_) => panic!("Expected error persisting manager"),
 695                         Err(e) => {
 696                                 assert_eq!(e.kind(), std::io::ErrorKind::Other);
 697                                 assert_eq!(e.get_ref().unwrap().to_string(), "test");
 698                         },
 699                 }
 700         }
 701
 702         #[test]
 703         fn test_network_graph_persist_error() {
 704                 // Test that if we encounter an error during network graph persistence, an error gets returned.
 705                 let nodes = create_nodes(2, "test_persist_network_graph_error".to_string());
 706                 let data_dir = nodes[0].persister.get_data_dir();
 707                 let persister = Arc::new(Persister::new(data_dir).with_graph_error(std::io::ErrorKind::Other, "test"));
 708                 let event_handler = |_: &_| {};
 709                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].net_graph_msg_handler.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
 710
 711                 match bg_processor.stop() {
 712                         Ok(_) => panic!("Expected error persisting network graph"),
 713                         Err(e) => {
 714                                 assert_eq!(e.kind(), std::io::ErrorKind::Other);
 715                                 assert_eq!(e.get_ref().unwrap().to_string(), "test");
 716                         },
 717                 }
 718         }
 719
 720         #[test]
 721         fn test_scorer_persist_error() {
 722                 // Test that if we encounter an error during scorer persistence, an error gets returned.
 723                 let nodes = create_nodes(2, "test_persist_scorer_error".to_string());
 724                 let data_dir = nodes[0].persister.get_data_dir();
 725                 let persister = Arc::new(Persister::new(data_dir).with_scorer_error(std::io::ErrorKind::Other, "test"));
 726                 let event_handler = |_: &_| {};
 727                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].net_graph_msg_handler.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
 728
 729                 match bg_processor.stop() {
 730                         Ok(_) => panic!("Expected error persisting scorer"),
 731                         Err(e) => {
 732                                 assert_eq!(e.kind(), std::io::ErrorKind::Other);
 733                                 assert_eq!(e.get_ref().unwrap().to_string(), "test");
 734                         },
 735                 }
 736         }
 737
 738         #[test]
 739         fn test_background_event_handling() {
 740                 let mut nodes = create_nodes(2, "test_background_event_handling".to_string());
 741                 let channel_value = 100000;
 742                 let data_dir = nodes[0].persister.get_data_dir();
 743                 let persister = Arc::new(Persister::new(data_dir.clone()));
 744
 745                 // Set up a background event handler for FundingGenerationReady events.
 746                 let (sender, receiver) = std::sync::mpsc::sync_channel(1);
 747                 let event_handler = move |event: &Event| {
 748                         sender.send(handle_funding_generation_ready!(event, channel_value)).unwrap();
 749                 };
 750                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].net_graph_msg_handler.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
 751
 752                 // Open a channel and check that the FundingGenerationReady event was handled.
 753                 begin_open_channel!(nodes[0], nodes[1], channel_value);
 754                 let (temporary_channel_id, funding_tx) = receiver
 755                         .recv_timeout(Duration::from_secs(EVENT_DEADLINE))
 756                         .expect("FundingGenerationReady not handled within deadline");
 757                 end_open_channel!(nodes[0], nodes[1], temporary_channel_id, funding_tx);
 758
 759                 // Confirm the funding transaction.
 760                 confirm_transaction(&mut nodes[0], &funding_tx);
 761                 let as_funding = get_event_msg!(nodes[0], MessageSendEvent::SendFundingLocked, nodes[1].node.get_our_node_id());
 762                 confirm_transaction(&mut nodes[1], &funding_tx);
 763                 let bs_funding = get_event_msg!(nodes[1], MessageSendEvent::SendFundingLocked, nodes[0].node.get_our_node_id());
 764                 nodes[0].node.handle_funding_locked(&nodes[1].node.get_our_node_id(), &bs_funding);
 765                 let _as_channel_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id());
 766                 nodes[1].node.handle_funding_locked(&nodes[0].node.get_our_node_id(), &as_funding);
 767                 let _bs_channel_update = get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id());
 768
 769                 assert!(bg_processor.stop().is_ok());
 770
 771                 // Set up a background event handler for SpendableOutputs events.
 772                 let (sender, receiver) = std::sync::mpsc::sync_channel(1);
 773                 let event_handler = move |event: &Event| sender.send(event.clone()).unwrap();
 774                 let persister = Arc::new(Persister::new(data_dir));
 775                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].net_graph_msg_handler.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
 776
 777                 // Force close the channel and check that the SpendableOutputs event was handled.
 778                 nodes[0].node.force_close_channel(&nodes[0].node.list_channels()[0].channel_id).unwrap();
 779                 let commitment_tx = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().pop().unwrap();
 780                 confirm_transaction_depth(&mut nodes[0], &commitment_tx, BREAKDOWN_TIMEOUT as u32);
 781                 let event = receiver
 782                         .recv_timeout(Duration::from_secs(EVENT_DEADLINE))
 783                         .expect("SpendableOutputs not handled within deadline");
 784                 match event {
 785                         Event::SpendableOutputs { .. } => {},
 786                         Event::ChannelClosed { .. } => {},
 787                         _ => panic!("Unexpected event: {:?}", event),
 788                 }
 789
 790                 assert!(bg_processor.stop().is_ok());
 791         }
 792
 793         #[test]
 794         fn test_invoice_payer() {
 795                 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
 796                 let random_seed_bytes = keys_manager.get_secure_random_bytes();
 797                 let nodes = create_nodes(2, "test_invoice_payer".to_string());
 798
 799                 // Initiate the background processors to watch each node.
 800                 let data_dir = nodes[0].persister.get_data_dir();
 801                 let persister = Arc::new(Persister::new(data_dir));
 802                 let router = DefaultRouter::new(Arc::clone(&nodes[0].network_graph), Arc::clone(&nodes[0].logger), random_seed_bytes);
 803                 let invoice_payer = Arc::new(InvoicePayer::new(Arc::clone(&nodes[0].node), router, Arc::clone(&nodes[0].scorer), Arc::clone(&nodes[0].logger), |_: &_| {}, RetryAttempts(2)));
 804                 let event_handler = Arc::clone(&invoice_payer);
 805                 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].net_graph_msg_handler.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
 806                 assert!(bg_processor.stop().is_ok());
 807         }
 808 }