Unify route finding methods

An upcoming Router interface will be used for finding a Route both when
initially sending a payment and also when retrying failed payment paths.
Unify the three varieties of get_route so the interface can consist of a
single method implemented by the new `find_route` method. Give get_route
pub(crate) visibility so it can still be used in tests.

Author: jkczyz

fuzz/src/full_stack.rs

@@ -38,7 +38,7 @@ use lightning::ln::peer_handler::{MessageHandler,PeerManager,SocketDescriptor,Ig
 use lightning::ln::msgs::DecodeError;
 use lightning::ln::script::ShutdownScript;
 use lightning::routing::network_graph::{NetGraphMsgHandler, NetworkGraph};
-use lightning::routing::router::{get_route, Payee};
+use lightning::routing::router::{find_route, Payee, RouteParameters};
 use lightning::routing::scorer::Scorer;
 use lightning::util::config::UserConfig;
 use lightning::util::errors::APIError;
@@ -437,9 +437,12 @@ pub fn do_test(data: &[u8], logger: &Arc<dyn Logger>) {
 				}
 			},
 			4 => {
-				let value = slice_to_be24(get_slice!(3)) as u64;
-				let payee = Payee::new(get_pubkey!());
-				let route = match get_route(&our_id, &payee, &net_graph_msg_handler.network_graph, None, value, 42, Arc::clone(&logger), &scorer) {
+				let params = RouteParameters {
+					payee: Payee::new(get_pubkey!()),
+					final_value_msat: slice_to_be24(get_slice!(3)) as u64,
+					final_cltv_expiry_delta: 42,
+				};
+				let route = match find_route(&our_id, &params, &net_graph_msg_handler.network_graph, None, Arc::clone(&logger), &scorer) {
 					Ok(route) => route,
 					Err(_) => return,
 				};
@@ -455,9 +458,12 @@ pub fn do_test(data: &[u8], logger: &Arc<dyn Logger>) {
 				}
 			},
 			15 => {
-				let value = slice_to_be24(get_slice!(3)) as u64;
-				let payee = Payee::new(get_pubkey!());
-				let mut route = match get_route(&our_id, &payee, &net_graph_msg_handler.network_graph, None, value, 42, Arc::clone(&logger), &scorer) {
+				let params = RouteParameters {
+					payee: Payee::new(get_pubkey!()),
+					final_value_msat: slice_to_be24(get_slice!(3)) as u64,
+					final_cltv_expiry_delta: 42,
+				};
+				let mut route = match find_route(&our_id, &params, &net_graph_msg_handler.network_graph, None, Arc::clone(&logger), &scorer) {
 					Ok(route) => route,
 					Err(_) => return,
 				};

fuzz/src/router.rs

@@ -16,7 +16,7 @@ use lightning::chain::transaction::OutPoint;
 use lightning::ln::channelmanager::{ChannelDetails, ChannelCounterparty};
 use lightning::ln::features::InitFeatures;
 use lightning::ln::msgs;
-use lightning::routing::router::{get_route, Payee, RouteHint, RouteHintHop};
+use lightning::routing::router::{find_route, Payee, RouteHint, RouteHintHop, RouteParameters};
 use lightning::routing::scorer::Scorer;
 use lightning::util::logger::Logger;
 use lightning::util::ser::Readable;
@@ -250,10 +250,14 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
 				}
 				let scorer = Scorer::new(0);
 				for target in node_pks.iter() {
-					let payee = Payee::new(*target).with_route_hints(last_hops.clone());
-					let _ = get_route(&our_pubkey, &payee, &net_graph,
+					let params = RouteParameters {
+						payee: Payee::new(*target).with_route_hints(last_hops.clone()),
+						final_value_msat: slice_to_be64(get_slice!(8)),
+						final_cltv_expiry_delta: slice_to_be32(get_slice!(4)),
+					};
+					let _ = find_route(&our_pubkey, &params, &net_graph,
 						first_hops.map(|c| c.iter().collect::<Vec<_>>()).as_ref().map(|a| a.as_slice()),
-						slice_to_be64(get_slice!(8)), slice_to_be32(get_slice!(4)), Arc::clone(&logger), &scorer);
+						Arc::clone(&logger), &scorer);
 				}
 			},
 		}

lightning-invoice/src/utils.rs

@@ -97,7 +97,7 @@ mod test {
 	use lightning::ln::functional_test_utils::*;
 	use lightning::ln::features::InitFeatures;
 	use lightning::ln::msgs::ChannelMessageHandler;
-	use lightning::routing::router;
+	use lightning::routing::router::{Payee, RouteParameters, find_route};
 	use lightning::routing::scorer::Scorer;
 	use lightning::util::events::MessageSendEventsProvider;
 	use lightning::util::test_utils;
@@ -113,23 +113,21 @@ mod test {
 		assert_eq!(invoice.min_final_cltv_expiry(), MIN_FINAL_CLTV_EXPIRY as u64);
 		assert_eq!(invoice.description(), InvoiceDescription::Direct(&Description("test".to_string())));
 
-		let payee = router::Payee::new(invoice.recover_payee_pub_key())
+		let payee = Payee::new(invoice.recover_payee_pub_key())
 			.with_features(invoice.features().unwrap().clone())
 			.with_route_hints(invoice.route_hints());
-		let amt_msat = invoice.amount_pico_btc().unwrap() / 10;
+		let params = RouteParameters {
+			payee,
+			final_value_msat: invoice.amount_milli_satoshis().unwrap(),
+			final_cltv_expiry_delta: invoice.min_final_cltv_expiry() as u32,
+		};
 		let first_hops = nodes[0].node.list_usable_channels();
 		let network_graph = &nodes[0].net_graph_msg_handler.network_graph;
 		let logger = test_utils::TestLogger::new();
 		let scorer = Scorer::new(0);
-		let route = router::get_route(
-			&nodes[0].node.get_our_node_id(),
-			&payee,
-			network_graph,
-			Some(&first_hops.iter().collect::<Vec<_>>()),
-			amt_msat,
-			invoice.min_final_cltv_expiry() as u32,
-			&logger,
-			&scorer,
+		let route = find_route(
+			&nodes[0].node.get_our_node_id(), &params, network_graph,
+			Some(&first_hops.iter().collect::<Vec<_>>()), &logger, &scorer,
 		).unwrap();
 
 		let payment_event = {

lightning/src/ln/channelmanager.rs

@@ -45,7 +45,7 @@ use chain::transaction::{OutPoint, TransactionData};
 use ln::{PaymentHash, PaymentPreimage, PaymentSecret};
 use ln::channel::{Channel, ChannelError, ChannelUpdateStatus, UpdateFulfillCommitFetch};
 use ln::features::{InitFeatures, NodeFeatures};
-use routing::router::{Payee, PaymentPathRetry, Route, RouteHop};
+use routing::router::{Payee, Route, RouteHop, RouteParameters};
 use ln::msgs;
 use ln::msgs::NetAddress;
 use ln::onion_utils;
@@ -3112,7 +3112,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 							!payment.get().is_fulfilled()
 						{
 							let retry = if let Some(payee_data) = payee {
-								Some(PaymentPathRetry {
+								Some(RouteParameters {
 									payee: payee_data,
 									final_value_msat: path_last_hop.fee_msat,
 									final_cltv_expiry_delta: path_last_hop.cltv_expiry_delta,
@@ -3183,7 +3183,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 				}
 				mem::drop(channel_state_lock);
 				let retry = if let Some(payee_data) = payee {
-					Some(PaymentPathRetry {
+					Some(RouteParameters {
 						payee: payee_data.clone(),
 						final_value_msat: path_last_hop.fee_msat,
 						final_cltv_expiry_delta: path_last_hop.cltv_expiry_delta,
@@ -6036,15 +6036,14 @@ mod tests {
 	use core::time::Duration;
 	use ln::{PaymentPreimage, PaymentHash, PaymentSecret};
 	use ln::channelmanager::{PaymentId, PaymentSendFailure};
-	use ln::features::{InitFeatures, InvoiceFeatures};
+	use ln::features::InitFeatures;
 	use ln::functional_test_utils::*;
 	use ln::msgs;
 	use ln::msgs::ChannelMessageHandler;
-	use routing::router::{Payee, get_keysend_route, get_route};
+	use routing::router::{Payee, RouteParameters, find_route};
 	use routing::scorer::Scorer;
 	use util::errors::APIError;
 	use util::events::{Event, MessageSendEvent, MessageSendEventsProvider};
-	use util::test_utils;
 
 	#[cfg(feature = "std")]
 	#[test]
@@ -6280,17 +6279,22 @@ mod tests {
 		let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 		let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 		create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
-		let logger = test_utils::TestLogger::new();
 		let scorer = Scorer::new(0);
 
 		// To start (1), send a regular payment but don't claim it.
 		let expected_route = [&nodes[1]];
 		let (payment_preimage, payment_hash, _) = route_payment(&nodes[0], &expected_route, 100_000);
 
 		// Next, attempt a keysend payment and make sure it fails.
-		let payee = Payee::new(expected_route.last().unwrap().node.get_our_node_id())
-			.with_features(InvoiceFeatures::known());
-		let route = get_route(&nodes[0].node.get_our_node_id(), &payee, &nodes[0].net_graph_msg_handler.network_graph, None, 100_000, TEST_FINAL_CLTV, &logger, &scorer).unwrap();
+		let params = RouteParameters {
+			payee: Payee::for_keysend(expected_route.last().unwrap().node.get_our_node_id()),
+			final_value_msat: 100_000,
+			final_cltv_expiry_delta: TEST_FINAL_CLTV,
+		};
+		let route = find_route(
+			&nodes[0].node.get_our_node_id(), &params,
+			&nodes[0].net_graph_msg_handler.network_graph, None, nodes[0].logger, &scorer
+		).unwrap();
 		nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage)).unwrap();
 		check_added_monitors!(nodes[0], 1);
 		let mut events = nodes[0].node.get_and_clear_pending_msg_events();
@@ -6318,7 +6322,10 @@ mod tests {
 
 		// To start (2), send a keysend payment but don't claim it.
 		let payment_preimage = PaymentPreimage([42; 32]);
-		let route = get_route(&nodes[0].node.get_our_node_id(), &payee, &nodes[0].net_graph_msg_handler.network_graph, None, 100_000, TEST_FINAL_CLTV, &logger, &scorer).unwrap();
+		let route = find_route(
+			&nodes[0].node.get_our_node_id(), &params,
+			&nodes[0].net_graph_msg_handler.network_graph, None, nodes[0].logger, &scorer
+		).unwrap();
 		let (payment_hash, _) = nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage)).unwrap();
 		check_added_monitors!(nodes[0], 1);
 		let mut events = nodes[0].node.get_and_clear_pending_msg_events();
@@ -6370,12 +6377,18 @@ mod tests {
 		nodes[1].node.peer_connected(&payer_pubkey, &msgs::Init { features: InitFeatures::known() });
 
 		let _chan = create_chan_between_nodes(&nodes[0], &nodes[1], InitFeatures::known(), InitFeatures::known());
+		let params = RouteParameters {
+			payee: Payee::for_keysend(payee_pubkey),
+			final_value_msat: 10000,
+			final_cltv_expiry_delta: 40,
+		};
 		let network_graph = &nodes[0].net_graph_msg_handler.network_graph;
 		let first_hops = nodes[0].node.list_usable_channels();
 		let scorer = Scorer::new(0);
-		let route = get_keysend_route(&payer_pubkey, network_graph, &payee_pubkey,
-                                  Some(&first_hops.iter().collect::<Vec<_>>()), &vec![], 10000, 40,
-                                  nodes[0].logger, &scorer).unwrap();
+		let route = find_route(
+			&payer_pubkey, &params, network_graph, Some(&first_hops.iter().collect::<Vec<_>>()),
+			nodes[0].logger, &scorer
+		).unwrap();
 
 		let test_preimage = PaymentPreimage([42; 32]);
 		let mismatch_payment_hash = PaymentHash([43; 32]);
@@ -6407,12 +6420,18 @@ mod tests {
 		nodes[1].node.peer_connected(&payer_pubkey, &msgs::Init { features: InitFeatures::known() });
 
 		let _chan = create_chan_between_nodes(&nodes[0], &nodes[1], InitFeatures::known(), InitFeatures::known());
+		let params = RouteParameters {
+			payee: Payee::for_keysend(payee_pubkey),
+			final_value_msat: 10000,
+			final_cltv_expiry_delta: 40,
+		};
 		let network_graph = &nodes[0].net_graph_msg_handler.network_graph;
 		let first_hops = nodes[0].node.list_usable_channels();
 		let scorer = Scorer::new(0);
-		let route = get_keysend_route(&payer_pubkey, network_graph, &payee_pubkey,
-                                  Some(&first_hops.iter().collect::<Vec<_>>()), &vec![], 10000, 40,
-                                  nodes[0].logger, &scorer).unwrap();
+		let route = find_route(
+			&payer_pubkey, &params, network_graph, Some(&first_hops.iter().collect::<Vec<_>>()),
+			nodes[0].logger, &scorer
+		).unwrap();
 
 		let test_preimage = PaymentPreimage([42; 32]);
 		let test_secret = PaymentSecret([43; 32]);

lightning/src/ln/features.rs

@@ -432,11 +432,11 @@ impl InvoiceFeatures {
 	/// Getting a route for a keysend payment to a private node requires providing the payee's
 	/// features (since they were not announced in a node announcement). However, keysend payments
 	/// don't have an invoice to pull the payee's features from, so this method is provided for use in
-	/// [`get_keysend_route`], thus omitting the need for payers to manually construct an
-	/// `InvoiceFeatures` for [`get_route`].
+	/// [`Payee::for_keysend`], thus omitting the need for payers to manually construct an
+	/// `InvoiceFeatures` for [`find_route`].
 	///
-	/// [`get_keysend_route`]: crate::routing::router::get_keysend_route
-	/// [`get_route`]: crate::routing::router::get_route
+	/// [`Payee::for_keysend`]: crate::routing::router::Payee::for_keysend
+	/// [`find_route`]: crate::routing::router::find_route
 	pub(crate) fn for_keysend() -> InvoiceFeatures {
 		InvoiceFeatures::empty().set_variable_length_onion_optional()
 	}

lightning/src/ln/functional_tests.rs

@@ -24,7 +24,7 @@ use ln::channel::{Channel, ChannelError};
 use ln::{chan_utils, onion_utils};
 use ln::chan_utils::HTLC_SUCCESS_TX_WEIGHT;
 use routing::network_graph::{NetworkUpdate, RoutingFees};
-use routing::router::{Payee, Route, RouteHop, RouteHint, RouteHintHop, get_route, get_keysend_route};
+use routing::router::{Payee, Route, RouteHop, RouteHint, RouteHintHop, RouteParameters, find_route, get_route};
 use routing::scorer::Scorer;
 use ln::features::{ChannelFeatures, InitFeatures, InvoiceFeatures, NodeFeatures};
 use ln::msgs;
@@ -9056,10 +9056,13 @@ fn test_keysend_payments_to_public_node() {
 	let network_graph = &nodes[0].net_graph_msg_handler.network_graph;
 	let payer_pubkey = nodes[0].node.get_our_node_id();
 	let payee_pubkey = nodes[1].node.get_our_node_id();
+	let params = RouteParameters {
+		payee: Payee::for_keysend(payee_pubkey),
+		final_value_msat: 10000,
+		final_cltv_expiry_delta: 40,
+	};
 	let scorer = Scorer::new(0);
-	let route = get_keysend_route(
-		&payer_pubkey, &network_graph, &payee_pubkey, None, &vec![], 10000, 40, nodes[0].logger, &scorer
-	).unwrap();
+	let route = find_route(&payer_pubkey, &params, &network_graph, None, nodes[0].logger, &scorer).unwrap();
 
 	let test_preimage = PaymentPreimage([42; 32]);
 	let (payment_hash, _) = nodes[0].node.send_spontaneous_payment(&route, Some(test_preimage)).unwrap();
@@ -9085,12 +9088,17 @@ fn test_keysend_payments_to_private_node() {
 	nodes[1].node.peer_connected(&payer_pubkey, &msgs::Init { features: InitFeatures::known() });
 
 	let _chan = create_chan_between_nodes(&nodes[0], &nodes[1], InitFeatures::known(), InitFeatures::known());
+	let params = RouteParameters {
+		payee: Payee::for_keysend(payee_pubkey),
+		final_value_msat: 10000,
+		final_cltv_expiry_delta: 40,
+	};
 	let network_graph = &nodes[0].net_graph_msg_handler.network_graph;
 	let first_hops = nodes[0].node.list_usable_channels();
 	let scorer = Scorer::new(0);
-	let route = get_keysend_route(
-		&payer_pubkey, &network_graph, &payee_pubkey, Some(&first_hops.iter().collect::<Vec<_>>()),
-		&vec![], 10000, 40, nodes[0].logger, &scorer
+	let route = find_route(
+		&payer_pubkey, &params, &network_graph, Some(&first_hops.iter().collect::<Vec<_>>()),
+		nodes[0].logger, &scorer
 	).unwrap();
 
 	let test_preimage = PaymentPreimage([42; 32]);