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.
5 #![deny(broken_intra_doc_links)]
9 #[macro_use] extern crate lightning;
12 use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
13 use lightning::chain::chainmonitor::ChainMonitor;
14 use lightning::chain::channelmonitor;
15 use lightning::chain::keysinterface::{Sign, KeysInterface};
16 use lightning::ln::channelmanager::ChannelManager;
17 use lightning::ln::msgs::{ChannelMessageHandler, RoutingMessageHandler};
18 use lightning::ln::peer_handler::{PeerManager, SocketDescriptor};
19 use lightning::util::events::{EventHandler, EventsProvider};
20 use lightning::util::logger::Logger;
22 use std::sync::atomic::{AtomicBool, Ordering};
24 use std::thread::JoinHandle;
25 use std::time::{Duration, Instant};
28 /// BackgroundProcessor takes care of tasks that (1) need to happen periodically to keep
29 /// Rust-Lightning running properly, and (2) either can or should be run in the background. Its
30 /// responsibilities are:
31 /// * Monitoring whether the ChannelManager needs to be re-persisted to disk, and if so,
32 /// writing it to disk/backups by invoking the callback given to it at startup.
33 /// ChannelManager persistence should be done in the background.
34 /// * Calling `ChannelManager::timer_tick_occurred()` and
35 /// `PeerManager::timer_tick_occurred()` every minute (can be done in the
38 /// Note that if ChannelManager persistence fails and the persisted manager becomes out-of-date,
39 /// then there is a risk of channels force-closing on startup when the manager realizes it's
40 /// outdated. However, as long as `ChannelMonitor` backups are sound, no funds besides those used
41 /// for unilateral chain closure fees are at risk.
42 pub struct BackgroundProcessor {
43 stop_thread: Arc<AtomicBool>,
44 thread_handle: Option<JoinHandle<Result<(), std::io::Error>>>,
48 const FRESHNESS_TIMER: u64 = 60;
50 const FRESHNESS_TIMER: u64 = 1;
52 /// Trait which handles persisting a [`ChannelManager`] to disk.
54 /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
55 pub trait ChannelManagerPersister<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
57 M::Target: 'static + chain::Watch<Signer>,
58 T::Target: 'static + BroadcasterInterface,
59 K::Target: 'static + KeysInterface<Signer = Signer>,
60 F::Target: 'static + FeeEstimator,
61 L::Target: 'static + Logger,
63 /// Persist the given [`ChannelManager`] to disk, returning an error if persistence failed
64 /// (which will cause the [`BackgroundProcessor`] which called this method to exit.
66 /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
67 fn persist_manager(&self, channel_manager: &ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error>;
70 impl<Fun, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
71 ChannelManagerPersister<Signer, M, T, K, F, L> for Fun where
72 M::Target: 'static + chain::Watch<Signer>,
73 T::Target: 'static + BroadcasterInterface,
74 K::Target: 'static + KeysInterface<Signer = Signer>,
75 F::Target: 'static + FeeEstimator,
76 L::Target: 'static + Logger,
77 Fun: Fn(&ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error>,
79 fn persist_manager(&self, channel_manager: &ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error> {
84 impl BackgroundProcessor {
85 /// Start a background thread that takes care of responsibilities enumerated in the [top-level
88 /// The thread runs indefinitely unless the object is dropped, [`stop`] is called, or
89 /// `persist_manager` returns an error. In case of an error, the error is retrieved by calling
90 /// either [`join`] or [`stop`].
92 /// Typically, users should either implement [`ChannelManagerPersister`] to never return an
93 /// error or call [`join`] and handle any error that may arise. For the latter case, the
94 /// `BackgroundProcessor` must be restarted by calling `start` again after handling the error.
96 /// `persist_manager` is responsible for writing out the [`ChannelManager`] to disk, and/or
97 /// uploading to one or more backup services. See [`ChannelManager::write`] for writing out a
98 /// [`ChannelManager`]. See [`FilesystemPersister::persist_manager`] for Rust-Lightning's
99 /// provided implementation.
101 /// [top-level documentation]: Self
102 /// [`join`]: Self::join
103 /// [`stop`]: Self::stop
104 /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
105 /// [`ChannelManager::write`]: lightning::ln::channelmanager::ChannelManager#impl-Writeable
106 /// [`FilesystemPersister::persist_manager`]: lightning_persister::FilesystemPersister::persist_manager
108 Signer: 'static + Sign,
109 CF: 'static + Deref + Send + Sync,
110 CW: 'static + Deref + Send + Sync,
111 T: 'static + Deref + Send + Sync,
112 K: 'static + Deref + Send + Sync,
113 F: 'static + Deref + Send + Sync,
114 L: 'static + Deref + Send + Sync,
115 P: 'static + Deref + Send + Sync,
116 Descriptor: 'static + SocketDescriptor + Send + Sync,
117 CMH: 'static + Deref + Send + Sync,
118 RMH: 'static + Deref + Send + Sync,
119 EH: 'static + EventHandler + Send + Sync,
120 CMP: 'static + Send + ChannelManagerPersister<Signer, CW, T, K, F, L>,
121 M: 'static + Deref<Target = ChainMonitor<Signer, CF, T, F, L, P>> + Send + Sync,
122 CM: 'static + Deref<Target = ChannelManager<Signer, CW, T, K, F, L>> + Send + Sync,
123 PM: 'static + Deref<Target = PeerManager<Descriptor, CMH, RMH, L>> + Send + Sync,
125 (persister: CMP, event_handler: EH, chain_monitor: M, channel_manager: CM, peer_manager: PM, logger: L) -> Self
127 CF::Target: 'static + chain::Filter,
128 CW::Target: 'static + chain::Watch<Signer>,
129 T::Target: 'static + BroadcasterInterface,
130 K::Target: 'static + KeysInterface<Signer = Signer>,
131 F::Target: 'static + FeeEstimator,
132 L::Target: 'static + Logger,
133 P::Target: 'static + channelmonitor::Persist<Signer>,
134 CMH::Target: 'static + ChannelMessageHandler,
135 RMH::Target: 'static + RoutingMessageHandler,
137 let stop_thread = Arc::new(AtomicBool::new(false));
138 let stop_thread_clone = stop_thread.clone();
139 let handle = thread::spawn(move || -> Result<(), std::io::Error> {
140 let mut current_time = Instant::now();
142 peer_manager.process_events();
143 channel_manager.process_pending_events(&event_handler);
144 chain_monitor.process_pending_events(&event_handler);
145 let updates_available =
146 channel_manager.await_persistable_update_timeout(Duration::from_millis(100));
147 if updates_available {
148 persister.persist_manager(&*channel_manager)?;
150 // Exit the loop if the background processor was requested to stop.
151 if stop_thread.load(Ordering::Acquire) == true {
152 log_trace!(logger, "Terminating background processor.");
155 if current_time.elapsed().as_secs() > FRESHNESS_TIMER {
156 log_trace!(logger, "Calling ChannelManager's and PeerManager's timer_tick_occurred");
157 channel_manager.timer_tick_occurred();
158 peer_manager.timer_tick_occurred();
159 current_time = Instant::now();
163 Self { stop_thread: stop_thread_clone, thread_handle: Some(handle) }
166 /// Join `BackgroundProcessor`'s thread, returning any error that occurred while persisting
167 /// [`ChannelManager`].
171 /// This function panics if the background thread has panicked such as while persisting or
174 /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
175 pub fn join(mut self) -> Result<(), std::io::Error> {
176 assert!(self.thread_handle.is_some());
180 /// Stop `BackgroundProcessor`'s thread, returning any error that occurred while persisting
181 /// [`ChannelManager`].
185 /// This function panics if the background thread has panicked such as while persisting or
188 /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
189 pub fn stop(mut self) -> Result<(), std::io::Error> {
190 assert!(self.thread_handle.is_some());
191 self.stop_and_join_thread()
194 fn stop_and_join_thread(&mut self) -> Result<(), std::io::Error> {
195 self.stop_thread.store(true, Ordering::Release);
199 fn join_thread(&mut self) -> Result<(), std::io::Error> {
200 match self.thread_handle.take() {
201 Some(handle) => handle.join().unwrap(),
207 impl Drop for BackgroundProcessor {
209 self.stop_and_join_thread().unwrap();
215 use bitcoin::blockdata::block::BlockHeader;
216 use bitcoin::blockdata::constants::genesis_block;
217 use bitcoin::blockdata::transaction::{Transaction, TxOut};
218 use bitcoin::network::constants::Network;
219 use lightning::chain::{BestBlock, Confirm, chainmonitor};
220 use lightning::chain::channelmonitor::ANTI_REORG_DELAY;
221 use lightning::chain::keysinterface::{InMemorySigner, KeysInterface, KeysManager};
222 use lightning::chain::transaction::OutPoint;
223 use lightning::get_event_msg;
224 use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, ChannelManager, SimpleArcChannelManager};
225 use lightning::ln::features::InitFeatures;
226 use lightning::ln::msgs::{ChannelMessageHandler, Init};
227 use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor};
228 use lightning::util::config::UserConfig;
229 use lightning::util::events::{Event, MessageSendEventsProvider, MessageSendEvent};
230 use lightning::util::ser::Writeable;
231 use lightning::util::test_utils;
232 use lightning_persister::FilesystemPersister;
234 use std::path::PathBuf;
235 use std::sync::{Arc, Mutex};
236 use std::time::Duration;
237 use super::{BackgroundProcessor, FRESHNESS_TIMER};
239 const EVENT_DEADLINE: u64 = 5 * FRESHNESS_TIMER;
241 #[derive(Clone, Eq, Hash, PartialEq)]
242 struct TestDescriptor{}
243 impl SocketDescriptor for TestDescriptor {
244 fn send_data(&mut self, _data: &[u8], _resume_read: bool) -> usize {
248 fn disconnect_socket(&mut self) {}
251 type ChainMonitor = chainmonitor::ChainMonitor<InMemorySigner, Arc<test_utils::TestChainSource>, Arc<test_utils::TestBroadcaster>, Arc<test_utils::TestFeeEstimator>, Arc<test_utils::TestLogger>, Arc<FilesystemPersister>>;
254 node: Arc<SimpleArcChannelManager<ChainMonitor, test_utils::TestBroadcaster, test_utils::TestFeeEstimator, test_utils::TestLogger>>,
255 peer_manager: Arc<PeerManager<TestDescriptor, Arc<test_utils::TestChannelMessageHandler>, Arc<test_utils::TestRoutingMessageHandler>, Arc<test_utils::TestLogger>>>,
256 chain_monitor: Arc<ChainMonitor>,
257 persister: Arc<FilesystemPersister>,
258 tx_broadcaster: Arc<test_utils::TestBroadcaster>,
259 logger: Arc<test_utils::TestLogger>,
260 best_block: BestBlock,
265 let data_dir = self.persister.get_data_dir();
266 match fs::remove_dir_all(data_dir.clone()) {
267 Err(e) => println!("Failed to remove test persister directory {}: {}", data_dir, e),
273 fn get_full_filepath(filepath: String, filename: String) -> String {
274 let mut path = PathBuf::from(filepath);
276 path.to_str().unwrap().to_string()
279 fn create_nodes(num_nodes: usize, persist_dir: String) -> Vec<Node> {
280 let mut nodes = Vec::new();
281 for i in 0..num_nodes {
282 let tx_broadcaster = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new()), blocks: Arc::new(Mutex::new(Vec::new()))});
283 let fee_estimator = Arc::new(test_utils::TestFeeEstimator { sat_per_kw: Mutex::new(253) });
284 let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
285 let logger = Arc::new(test_utils::TestLogger::with_id(format!("node {}", i)));
286 let persister = Arc::new(FilesystemPersister::new(format!("{}_persister_{}", persist_dir, i)));
287 let seed = [i as u8; 32];
288 let network = Network::Testnet;
289 let now = Duration::from_secs(genesis_block(network).header.time as u64);
290 let keys_manager = Arc::new(KeysManager::new(&seed, now.as_secs(), now.subsec_nanos()));
291 let chain_monitor = Arc::new(chainmonitor::ChainMonitor::new(Some(chain_source.clone()), tx_broadcaster.clone(), logger.clone(), fee_estimator.clone(), persister.clone()));
292 let best_block = BestBlock::from_genesis(network);
293 let params = ChainParameters { network, best_block };
294 let manager = Arc::new(ChannelManager::new(fee_estimator.clone(), chain_monitor.clone(), tx_broadcaster.clone(), logger.clone(), keys_manager.clone(), UserConfig::default(), params));
295 let msg_handler = MessageHandler { chan_handler: Arc::new(test_utils::TestChannelMessageHandler::new()), route_handler: Arc::new(test_utils::TestRoutingMessageHandler::new() )};
296 let peer_manager = Arc::new(PeerManager::new(msg_handler, keys_manager.get_node_secret(), &seed, logger.clone()));
297 let node = Node { node: manager, peer_manager, chain_monitor, persister, tx_broadcaster, logger, best_block };
301 for i in 0..num_nodes {
302 for j in (i+1)..num_nodes {
303 nodes[i].node.peer_connected(&nodes[j].node.get_our_node_id(), &Init { features: InitFeatures::known() });
304 nodes[j].node.peer_connected(&nodes[i].node.get_our_node_id(), &Init { features: InitFeatures::known() });
311 macro_rules! open_channel {
312 ($node_a: expr, $node_b: expr, $channel_value: expr) => {{
313 begin_open_channel!($node_a, $node_b, $channel_value);
314 let events = $node_a.node.get_and_clear_pending_events();
315 assert_eq!(events.len(), 1);
316 let (temporary_channel_id, tx) = handle_funding_generation_ready!(events[0], $channel_value);
317 end_open_channel!($node_a, $node_b, temporary_channel_id, tx);
322 macro_rules! begin_open_channel {
323 ($node_a: expr, $node_b: expr, $channel_value: expr) => {{
324 $node_a.node.create_channel($node_b.node.get_our_node_id(), $channel_value, 100, 42, None).unwrap();
325 $node_b.node.handle_open_channel(&$node_a.node.get_our_node_id(), InitFeatures::known(), &get_event_msg!($node_a, MessageSendEvent::SendOpenChannel, $node_b.node.get_our_node_id()));
326 $node_a.node.handle_accept_channel(&$node_b.node.get_our_node_id(), InitFeatures::known(), &get_event_msg!($node_b, MessageSendEvent::SendAcceptChannel, $node_a.node.get_our_node_id()));
330 macro_rules! handle_funding_generation_ready {
331 ($event: expr, $channel_value: expr) => {{
333 Event::FundingGenerationReady { ref temporary_channel_id, ref channel_value_satoshis, ref output_script, user_channel_id } => {
334 assert_eq!(*channel_value_satoshis, $channel_value);
335 assert_eq!(user_channel_id, 42);
337 let tx = Transaction { version: 1 as i32, lock_time: 0, input: Vec::new(), output: vec![TxOut {
338 value: *channel_value_satoshis, script_pubkey: output_script.clone(),
340 (*temporary_channel_id, tx)
342 _ => panic!("Unexpected event"),
347 macro_rules! end_open_channel {
348 ($node_a: expr, $node_b: expr, $temporary_channel_id: expr, $tx: expr) => {{
349 $node_a.node.funding_transaction_generated(&$temporary_channel_id, $tx.clone()).unwrap();
350 $node_b.node.handle_funding_created(&$node_a.node.get_our_node_id(), &get_event_msg!($node_a, MessageSendEvent::SendFundingCreated, $node_b.node.get_our_node_id()));
351 $node_a.node.handle_funding_signed(&$node_b.node.get_our_node_id(), &get_event_msg!($node_b, MessageSendEvent::SendFundingSigned, $node_a.node.get_our_node_id()));
355 fn confirm_transaction_depth(node: &mut Node, tx: &Transaction, depth: u32) {
357 let prev_blockhash = node.best_block.block_hash();
358 let height = node.best_block.height() + 1;
359 let header = BlockHeader { version: 0x20000000, prev_blockhash, merkle_root: Default::default(), time: height, bits: 42, nonce: 42 };
360 let txdata = vec![(0, tx)];
361 node.best_block = BestBlock::new(header.block_hash(), height);
364 node.node.transactions_confirmed(&header, &txdata, height);
365 node.chain_monitor.transactions_confirmed(&header, &txdata, height);
368 node.node.best_block_updated(&header, height);
369 node.chain_monitor.best_block_updated(&header, height);
375 fn confirm_transaction(node: &mut Node, tx: &Transaction) {
376 confirm_transaction_depth(node, tx, ANTI_REORG_DELAY);
380 fn test_background_processor() {
381 // Test that when a new channel is created, the ChannelManager needs to be re-persisted with
382 // updates. Also test that when new updates are available, the manager signals that it needs
383 // re-persistence and is successfully re-persisted.
384 let nodes = create_nodes(2, "test_background_processor".to_string());
386 // Go through the channel creation process so that each node has something to persist. Since
387 // open_channel consumes events, it must complete before starting BackgroundProcessor to
388 // avoid a race with processing events.
389 let tx = open_channel!(nodes[0], nodes[1], 100000);
391 // Initiate the background processors to watch each node.
392 let data_dir = nodes[0].persister.get_data_dir();
393 let persister = move |node: &ChannelManager<InMemorySigner, Arc<ChainMonitor>, Arc<test_utils::TestBroadcaster>, Arc<KeysManager>, Arc<test_utils::TestFeeEstimator>, Arc<test_utils::TestLogger>>| FilesystemPersister::persist_manager(data_dir.clone(), node);
394 let event_handler = |_| {};
395 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone());
397 macro_rules! check_persisted_data {
398 ($node: expr, $filepath: expr, $expected_bytes: expr) => {
399 match $node.write(&mut $expected_bytes) {
402 match std::fs::read($filepath) {
404 if bytes == $expected_bytes {
414 Err(e) => panic!("Unexpected error: {}", e)
419 // Check that the initial channel manager data is persisted as expected.
420 let filepath = get_full_filepath("test_background_processor_persister_0".to_string(), "manager".to_string());
421 let mut expected_bytes = Vec::new();
422 check_persisted_data!(nodes[0].node, filepath.clone(), expected_bytes);
424 if !nodes[0].node.get_persistence_condvar_value() { break }
427 // Force-close the channel.
428 nodes[0].node.force_close_channel(&OutPoint { txid: tx.txid(), index: 0 }.to_channel_id()).unwrap();
430 // Check that the force-close updates are persisted.
431 let mut expected_bytes = Vec::new();
432 check_persisted_data!(nodes[0].node, filepath.clone(), expected_bytes);
434 if !nodes[0].node.get_persistence_condvar_value() { break }
437 assert!(bg_processor.stop().is_ok());
441 fn test_timer_tick_called() {
442 // Test that ChannelManager's and PeerManager's `timer_tick_occurred` is called every
443 // `FRESHNESS_TIMER`.
444 let nodes = create_nodes(1, "test_timer_tick_called".to_string());
445 let data_dir = nodes[0].persister.get_data_dir();
446 let persister = move |node: &ChannelManager<InMemorySigner, Arc<ChainMonitor>, Arc<test_utils::TestBroadcaster>, Arc<KeysManager>, Arc<test_utils::TestFeeEstimator>, Arc<test_utils::TestLogger>>| FilesystemPersister::persist_manager(data_dir.clone(), node);
447 let event_handler = |_| {};
448 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone());
450 let log_entries = nodes[0].logger.lines.lock().unwrap();
451 let desired_log = "Calling ChannelManager's and PeerManager's timer_tick_occurred".to_string();
452 if log_entries.get(&("lightning_background_processor".to_string(), desired_log)).is_some() {
457 assert!(bg_processor.stop().is_ok());
461 fn test_persist_error() {
462 // Test that if we encounter an error during manager persistence, the thread panics.
463 let nodes = create_nodes(2, "test_persist_error".to_string());
464 open_channel!(nodes[0], nodes[1], 100000);
466 let persister = |_: &_| Err(std::io::Error::new(std::io::ErrorKind::Other, "test"));
467 let event_handler = |_| {};
468 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone());
469 match bg_processor.join() {
470 Ok(_) => panic!("Expected error persisting manager"),
472 assert_eq!(e.kind(), std::io::ErrorKind::Other);
473 assert_eq!(e.get_ref().unwrap().to_string(), "test");
479 fn test_background_event_handling() {
480 let mut nodes = create_nodes(2, "test_background_event_handling".to_string());
481 let channel_value = 100000;
482 let data_dir = nodes[0].persister.get_data_dir();
483 let persister = move |node: &_| FilesystemPersister::persist_manager(data_dir.clone(), node);
485 // Set up a background event handler for FundingGenerationReady events.
486 let (sender, receiver) = std::sync::mpsc::sync_channel(1);
487 let event_handler = move |event| {
488 sender.send(handle_funding_generation_ready!(event, channel_value)).unwrap();
490 let bg_processor = BackgroundProcessor::start(persister.clone(), event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone());
492 // Open a channel and check that the FundingGenerationReady event was handled.
493 begin_open_channel!(nodes[0], nodes[1], channel_value);
494 let (temporary_channel_id, funding_tx) = receiver
495 .recv_timeout(Duration::from_secs(EVENT_DEADLINE))
496 .expect("FundingGenerationReady not handled within deadline");
497 end_open_channel!(nodes[0], nodes[1], temporary_channel_id, funding_tx);
499 // Confirm the funding transaction.
500 confirm_transaction(&mut nodes[0], &funding_tx);
501 let as_funding = get_event_msg!(nodes[0], MessageSendEvent::SendFundingLocked, nodes[1].node.get_our_node_id());
502 confirm_transaction(&mut nodes[1], &funding_tx);
503 let bs_funding = get_event_msg!(nodes[1], MessageSendEvent::SendFundingLocked, nodes[0].node.get_our_node_id());
504 nodes[0].node.handle_funding_locked(&nodes[1].node.get_our_node_id(), &bs_funding);
505 let _as_channel_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id());
506 nodes[1].node.handle_funding_locked(&nodes[0].node.get_our_node_id(), &as_funding);
507 let _bs_channel_update = get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id());
509 assert!(bg_processor.stop().is_ok());
511 // Set up a background event handler for SpendableOutputs events.
512 let (sender, receiver) = std::sync::mpsc::sync_channel(1);
513 let event_handler = move |event| sender.send(event).unwrap();
514 let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].peer_manager.clone(), nodes[0].logger.clone());
516 // Force close the channel and check that the SpendableOutputs event was handled.
517 nodes[0].node.force_close_channel(&nodes[0].node.list_channels()[0].channel_id).unwrap();
518 let commitment_tx = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().pop().unwrap();
519 confirm_transaction_depth(&mut nodes[0], &commitment_tx, BREAKDOWN_TIMEOUT as u32);
521 .recv_timeout(Duration::from_secs(EVENT_DEADLINE))
522 .expect("SpendableOutputs not handled within deadline");
524 Event::SpendableOutputs { .. } => {},
525 _ => panic!("Unexpected event: {:?}", event),
528 assert!(bg_processor.stop().is_ok());