Add NetworkGraph persistence

Instead of creating a separate trait for persisting NetworkGraph, use and rename the existing ChannelManagerPersister to handle them both. persist_graph is then called on removal of stale channels and on exit.

Author: jurvis

lightning-background-processor/src/lib.rs

@@ -75,10 +75,16 @@ const PING_TIMER: u64 = 1;
 /// Prune the network graph of stale entries hourly.
 const NETWORK_PRUNE_TIMER: u64 = 60 * 60;
 
-/// Trait which handles persisting a [`ChannelManager`] to disk.
+#[cfg(not(test))]
+const FIRST_NETWORK_PRUNE_TIMER: u64 = 60;
+#[cfg(test)]
+const FIRST_NETWORK_PRUNE_TIMER: u64 = 1;
+
+/// Trait which handles persisting a [`ChannelManager`] and [`NetworkGraph`] to disk.
 ///
 /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
-pub trait ChannelManagerPersister<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
+/// [`NetworkGraph`]: lightning::routing::network_graph::NetworkGraph
+pub trait Persister<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
 where
 	M::Target: 'static + chain::Watch<Signer>,
 	T::Target: 'static + BroadcasterInterface,
@@ -87,24 +93,15 @@ where
 	L::Target: 'static + Logger,
 {
 	/// Persist the given [`ChannelManager`] to disk, returning an error if persistence failed
-	/// (which will cause the [`BackgroundProcessor`] which called this method to exit.
+	/// (which will cause the [`BackgroundProcessor`] which called this method to exit.)
 	///
 	/// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
 	fn persist_manager(&self, channel_manager: &ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error>;
-}
 
-impl<Fun, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
-ChannelManagerPersister<Signer, M, T, K, F, L> for Fun where
-	M::Target: 'static + chain::Watch<Signer>,
-	T::Target: 'static + BroadcasterInterface,
-	K::Target: 'static + KeysInterface<Signer = Signer>,
-	F::Target: 'static + FeeEstimator,
-	L::Target: 'static + Logger,
-	Fun: Fn(&ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error>,
-{
-	fn persist_manager(&self, channel_manager: &ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error> {
-		self(channel_manager)
-	}
+	/// Persist the given [`NetworkGraph`] to disk, returning an error if persistence failed.
+	///
+	/// [`NetworkGraph`]: lightning::routing::network_graph::NetworkGraph
+	fn persist_graph(&self, network_graph: &NetworkGraph) -> Result<(), std::io::Error>;
 }
 
 /// Decorates an [`EventHandler`] with common functionality provided by standard [`EventHandler`]s.
@@ -151,7 +148,12 @@ impl BackgroundProcessor {
 	/// [`ChannelManager`]. See [`FilesystemPersister::persist_manager`] for Rust-Lightning's
 	/// provided implementation.
 	///
-	/// Typically, users should either implement [`ChannelManagerPersister`] to never return an
+	/// `persist_graph` is responsible for writing out the [`NetworkGraph`] to disk. See
+	/// [`NetworkGraph::write`] for writing out a [`NetworkGraph`]. See
+	/// [`FilesystemPersister::persist_network_graph`] for Rust-Lightning's
+	/// provided implementation.
+	///
+	/// Typically, users should either implement [`Persister::persist_manager`] to never return an
 	/// error or call [`join`] and handle any error that may arise. For the latter case,
 	/// `BackgroundProcessor` must be restarted by calling `start` again after handling the error.
 	///
@@ -168,7 +170,9 @@ impl BackgroundProcessor {
 	/// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
 	/// [`ChannelManager::write`]: lightning::ln::channelmanager::ChannelManager#impl-Writeable
 	/// [`FilesystemPersister::persist_manager`]: lightning_persister::FilesystemPersister::persist_manager
+	/// [`FilesystemPersister::persist_network_graph`]: lightning_persister::FilesystemPersister::persist_network_graph
 	/// [`NetworkGraph`]: lightning::routing::network_graph::NetworkGraph
+	/// [`NetworkGraph::write`]: lightning::routing::network_graph::NetworkGraph#impl-Writeable
 	pub fn start<
 		Signer: 'static + Sign,
 		CA: 'static + Deref + Send + Sync,
@@ -184,14 +188,14 @@ impl BackgroundProcessor {
 		CMH: 'static + Deref + Send + Sync,
 		RMH: 'static + Deref + Send + Sync,
 		EH: 'static + EventHandler + Send,
-		CMP: 'static + Send + ChannelManagerPersister<Signer, CW, T, K, F, L>,
+		PS: 'static + Send + Persister<Signer, CW, T, K, F, L>,
 		M: 'static + Deref<Target = ChainMonitor<Signer, CF, T, F, L, P>> + Send + Sync,
 		CM: 'static + Deref<Target = ChannelManager<Signer, CW, T, K, F, L>> + Send + Sync,
 		NG: 'static + Deref<Target = NetGraphMsgHandler<G, CA, L>> + Send + Sync,
 		UMH: 'static + Deref + Send + Sync,
 		PM: 'static + Deref<Target = PeerManager<Descriptor, CMH, RMH, L, UMH>> + Send + Sync,
 	>(
-		persister: CMP, event_handler: EH, chain_monitor: M, channel_manager: CM,
+		persister: PS, event_handler: EH, chain_monitor: M, channel_manager: CM,
 		net_graph_msg_handler: Option<NG>, peer_manager: PM, logger: L
 	) -> Self
 	where
@@ -273,19 +277,29 @@ impl BackgroundProcessor {
 				// falling back to our usual hourly prunes. This avoids short-lived clients never
 				// pruning their network graph. We run once 60 seconds after startup before
 				// continuing our normal cadence.
-				if last_prune_call.elapsed().as_secs() > if have_pruned { NETWORK_PRUNE_TIMER } else { 60 } {
+				if last_prune_call.elapsed().as_secs() > if have_pruned { NETWORK_PRUNE_TIMER } else { FIRST_NETWORK_PRUNE_TIMER } {
 					if let Some(ref handler) = net_graph_msg_handler {
 						log_trace!(logger, "Pruning network graph of stale entries");
 						handler.network_graph().remove_stale_channels();
+						if persister.persist_graph(handler.network_graph()).is_err() {
+							log_error!(logger, "Warning: Failed to persist network graph, check your disk and permissions");
+						}
 						last_prune_call = Instant::now();
 						have_pruned = true;
 					}
 				}
 			}
+
 			// After we exit, ensure we persist the ChannelManager one final time - this avoids
 			// some races where users quit while channel updates were in-flight, with
 			// ChannelMonitor update(s) persisted without a corresponding ChannelManager update.
-			persister.persist_manager(&*channel_manager)
+			persister.persist_manager(&*channel_manager)?;
+
+			// Persist NetworkGraph on exit
+			if let Some(ref handler) = net_graph_msg_handler {
+				persister.persist_graph(handler.network_graph())?;
+			}
+			Ok(())
 		});
 		Self { stop_thread: stop_thread_clone, thread_handle: Some(handle) }
 	}
@@ -343,9 +357,10 @@ mod tests {
 	use bitcoin::blockdata::constants::genesis_block;
 	use bitcoin::blockdata::transaction::{Transaction, TxOut};
 	use bitcoin::network::constants::Network;
-	use lightning::chain::{BestBlock, Confirm, chainmonitor};
+	use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
+	use lightning::chain::{BestBlock, Confirm, chainmonitor, self};
 	use lightning::chain::channelmonitor::ANTI_REORG_DELAY;
-	use lightning::chain::keysinterface::{InMemorySigner, Recipient, KeysInterface, KeysManager};
+	use lightning::chain::keysinterface::{InMemorySigner, Recipient, KeysInterface, KeysManager, Sign};
 	use lightning::chain::transaction::OutPoint;
 	use lightning::get_event_msg;
 	use lightning::ln::channelmanager::{BREAKDOWN_TIMEOUT, ChainParameters, ChannelManager, SimpleArcChannelManager};
@@ -355,12 +370,14 @@ mod tests {
 	use lightning::routing::network_graph::{NetworkGraph, NetGraphMsgHandler};
 	use lightning::util::config::UserConfig;
 	use lightning::util::events::{Event, MessageSendEventsProvider, MessageSendEvent};
+	use lightning::util::logger::Logger;
 	use lightning::util::ser::Writeable;
 	use lightning::util::test_utils;
 	use lightning_invoice::payment::{InvoicePayer, RetryAttempts};
 	use lightning_invoice::utils::DefaultRouter;
 	use lightning_persister::FilesystemPersister;
 	use std::fs;
+	use std::ops::Deref;
 	use std::path::PathBuf;
 	use std::sync::{Arc, Mutex};
 	use std::time::Duration;
@@ -402,6 +419,27 @@ mod tests {
 		}
 	}
 
+	#[derive(Clone)]
+	struct Persister {
+		data_dir: String,
+	}
+
+	impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L:Deref> super::Persister<Signer, M, T, K, F, L> for Persister where
+		M::Target: 'static + chain::Watch<Signer>,
+		T::Target: 'static + BroadcasterInterface,
+		K::Target: 'static + KeysInterface<Signer = Signer>,
+		F::Target: 'static + FeeEstimator,
+		L::Target: 'static + Logger,
+	{
+		fn persist_manager(&self, channel_manager: &ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error> {
+			FilesystemPersister::persist_manager(self.data_dir.clone(), channel_manager)
+		}
+
+		fn persist_graph(&self, network_graph: &NetworkGraph) -> Result<(), std::io::Error> {
+			FilesystemPersister::persist_network_graph(self.data_dir.clone(), network_graph)
+		}
+	}
+
 	fn get_full_filepath(filepath: String, filename: String) -> String {
 		let mut path = PathBuf::from(filepath);
 		path.push(filename);
@@ -525,7 +563,7 @@ mod tests {
 
 		// Initiate the background processors to watch each node.
 		let data_dir = nodes[0].persister.get_data_dir();
-		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);
+		let persister = Persister { data_dir };
 		let event_handler = |_: &_| {};
 		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());
 
@@ -556,6 +594,7 @@ mod tests {
 		let filepath = get_full_filepath("test_background_processor_persister_0".to_string(), "manager".to_string());
 		let mut expected_bytes = Vec::new();
 		check_persisted_data!(nodes[0].node, filepath.clone(), expected_bytes);
+
 		loop {
 			if !nodes[0].node.get_persistence_condvar_value() { break }
 		}
@@ -570,6 +609,14 @@ mod tests {
 			if !nodes[0].node.get_persistence_condvar_value() { break }
 		}
 
+		// Check network graph is persisted
+		let filepath = get_full_filepath("test_background_processor_persister_0".to_string(), "network_graph".to_string());
+		let mut expected_bytes = Vec::new();
+		if let Some(handler) = nodes[0].net_graph_msg_handler.clone() {
+			let network_graph = handler.network_graph();
+			check_persisted_data!(network_graph, filepath.clone(), expected_bytes);
+		}
+
 		assert!(bg_processor.stop().is_ok());
 	}
 
@@ -579,7 +626,7 @@ mod tests {
 		// `FRESHNESS_TIMER`.
 		let nodes = create_nodes(1, "test_timer_tick_called".to_string());
 		let data_dir = nodes[0].persister.get_data_dir();
-		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);
+		let persister = Persister { data_dir };
 		let event_handler = |_: &_| {};
 		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());
 		loop {
@@ -596,12 +643,33 @@ mod tests {
 	}
 
 	#[test]
-	fn test_persist_error() {
+	fn test_channel_manager_persist_error() {
 		// Test that if we encounter an error during manager persistence, the thread panics.
 		let nodes = create_nodes(2, "test_persist_error".to_string());
 		open_channel!(nodes[0], nodes[1], 100000);
 
-		let persister = |_: &_| Err(std::io::Error::new(std::io::ErrorKind::Other, "test"));
+		struct ChannelManagerErrorPersister {
+			data_dir: String,
+		}
+
+		impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L:Deref> super::Persister<Signer, M, T, K, F, L> for ChannelManagerErrorPersister where
+			M::Target: 'static + chain::Watch<Signer>,
+			T::Target: 'static + BroadcasterInterface,
+			K::Target: 'static + KeysInterface<Signer = Signer>,
+			F::Target: 'static + FeeEstimator,
+			L::Target: 'static + Logger,
+		{
+			fn persist_manager(&self, _channel_manager: &ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error> {
+				Err(std::io::Error::new(std::io::ErrorKind::Other, "test"))
+			}
+
+			fn persist_graph(&self, network_graph: &NetworkGraph) -> Result<(), std::io::Error> {
+				FilesystemPersister::persist_network_graph(self.data_dir.clone(), network_graph)
+			}
+		}
+
+		let data_dir = nodes[0].persister.get_data_dir();
+		let persister = ChannelManagerErrorPersister{ data_dir };
 		let event_handler = |_: &_| {};
 		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());
 		match bg_processor.join() {
@@ -613,12 +681,52 @@ mod tests {
 		}
 	}
 
+	#[test]
+	fn test_network_graph_persist_error() {
+		// Test that if we encounter an error during network graph persistence, an error gets returned.
+		let nodes = create_nodes(2, "test_persist_network_graph_error".to_string());
+		open_channel!(nodes[0], nodes[1], 100000);
+
+		struct NetworkGraphErrorPersister {
+			data_dir: String,
+		}
+
+		impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L:Deref> super::Persister<Signer, M, T, K, F, L> for NetworkGraphErrorPersister where
+			M::Target: 'static + chain::Watch<Signer>,
+			T::Target: 'static + BroadcasterInterface,
+			K::Target: 'static + KeysInterface<Signer = Signer>,
+			F::Target: 'static + FeeEstimator,
+			L::Target: 'static + Logger,
+		{
+			fn persist_manager(&self, channel_manager: &ChannelManager<Signer, M, T, K, F, L>) -> Result<(), std::io::Error> {
+				FilesystemPersister::persist_manager(self.data_dir.clone(), channel_manager)
+			}
+
+			fn persist_graph(&self, _network_graph: &NetworkGraph) -> Result<(), std::io::Error> {
+				Err(std::io::Error::new(std::io::ErrorKind::Other, "test"))
+			}
+		}
+
+		let data_dir = nodes[0].persister.get_data_dir();
+		let persister = NetworkGraphErrorPersister { data_dir };
+		let event_handler = |_: &_| {};
+		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());
+
+		match bg_processor.stop() {
+			Ok(_) => panic!("Expected error persisting network graph"),
+			Err(e) => {
+				assert_eq!(e.kind(), std::io::ErrorKind::Other);
+				assert_eq!(e.get_ref().unwrap().to_string(), "test");
+			},
+		}
+	}
+
 	#[test]
 	fn test_background_event_handling() {
 		let mut nodes = create_nodes(2, "test_background_event_handling".to_string());
 		let channel_value = 100000;
 		let data_dir = nodes[0].persister.get_data_dir();
-		let persister = move |node: &_| FilesystemPersister::persist_manager(data_dir.clone(), node);
+		let persister = Persister { data_dir };
 
 		// Set up a background event handler for FundingGenerationReady events.
 		let (sender, receiver) = std::sync::mpsc::sync_channel(1);
@@ -675,7 +783,7 @@ mod tests {
 
 		// Initiate the background processors to watch each node.
 		let data_dir = nodes[0].persister.get_data_dir();
-		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);
+		let persister = Persister { data_dir };
 		let scorer = Arc::new(Mutex::new(test_utils::TestScorer::with_penalty(0)));
 		let router = DefaultRouter::new(Arc::clone(&nodes[0].network_graph), Arc::clone(&nodes[0].logger), random_seed_bytes);
 		let invoice_payer = Arc::new(InvoicePayer::new(Arc::clone(&nodes[0].node), router, scorer, Arc::clone(&nodes[0].logger), |_: &_| {}, RetryAttempts(2)));

lightning-persister/src/lib.rs

@@ -16,6 +16,7 @@ extern crate libc;
 
 use bitcoin::hash_types::{BlockHash, Txid};
 use bitcoin::hashes::hex::{FromHex, ToHex};
+use lightning::routing::network_graph::NetworkGraph;
 use crate::util::DiskWriteable;
 use lightning::chain;
 use lightning::chain::chaininterface::{BroadcasterInterface, FeeEstimator};
@@ -66,6 +67,12 @@ where
 	}
 }
 
+impl DiskWriteable for NetworkGraph {
+	fn write_to_file(&self, writer: &mut fs::File) -> Result<(), std::io::Error> {
+		self.write(writer)
+	}
+}
+
 impl FilesystemPersister {
 	/// Initialize a new FilesystemPersister and set the path to the individual channels'
 	/// files.
@@ -103,6 +110,13 @@ impl FilesystemPersister {
 		util::write_to_file(path, "manager".to_string(), manager)
 	}
 
+	/// Write the provided `NetworkGraph` to the path provided at `FilesystemPersister`
+	/// initialization, within a file called "network_graph"
+	pub fn persist_network_graph(data_dir: String, network_graph: &NetworkGraph) -> Result<(), std::io::Error> {
+		let path = PathBuf::from(data_dir);
+		util::write_to_file(path, "network_graph".to_string(), network_graph)
+	}
+
 	/// Read `ChannelMonitor`s from disk.
 	pub fn read_channelmonitors<Signer: Sign, K: Deref> (
 		&self, keys_manager: K