Print next and previous nodes for PaymentForwarded
[ldk-sample] / src / main.rs
index 31fb84eeebeb8e79f19602b41b12fec47558bc1f..edcec9b4ade5d6dcf01666e18a90146dc8b7b492 100644 (file)
@@ -9,8 +9,6 @@ use crate::disk::FilesystemLogger;
 use bitcoin::blockdata::constants::genesis_block;
 use bitcoin::blockdata::transaction::Transaction;
 use bitcoin::consensus::encode;
-use bitcoin::hashes::sha256::Hash as Sha256;
-use bitcoin::hashes::Hash;
 use bitcoin::network::constants::Network;
 use bitcoin::secp256k1::Secp256k1;
 use bitcoin::BlockHash;
@@ -18,26 +16,30 @@ use bitcoin_bech32::WitnessProgram;
 use lightning::chain;
 use lightning::chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, FeeEstimator};
 use lightning::chain::chainmonitor;
-use lightning::chain::keysinterface::{InMemorySigner, KeysInterface, KeysManager};
-use lightning::chain::Filter;
-use lightning::chain::Watch;
+use lightning::chain::keysinterface::{InMemorySigner, KeysInterface, KeysManager, Recipient};
+use lightning::chain::{BestBlock, Filter, Watch};
 use lightning::ln::channelmanager;
 use lightning::ln::channelmanager::{
-       BestBlock, ChainParameters, ChannelManagerReadArgs, SimpleArcChannelManager,
+       ChainParameters, ChannelManagerReadArgs, SimpleArcChannelManager,
 };
-use lightning::ln::peer_handler::{MessageHandler, SimpleArcPeerManager};
+use lightning::ln::peer_handler::{IgnoringMessageHandler, MessageHandler, SimpleArcPeerManager};
 use lightning::ln::{PaymentHash, PaymentPreimage, PaymentSecret};
-use lightning::routing::network_graph::NetGraphMsgHandler;
+use lightning::routing::gossip;
+use lightning::routing::gossip::{NodeId, P2PGossipSync};
+use lightning::routing::scoring::ProbabilisticScorer;
 use lightning::util::config::UserConfig;
-use lightning::util::events::{Event, EventsProvider};
+use lightning::util::events::{Event, PaymentPurpose};
 use lightning::util::ser::ReadableArgs;
 use lightning_background_processor::BackgroundProcessor;
 use lightning_block_sync::init;
 use lightning_block_sync::poll;
 use lightning_block_sync::SpvClient;
 use lightning_block_sync::UnboundedCache;
+use lightning_invoice::payment;
+use lightning_invoice::utils::DefaultRouter;
 use lightning_net_tokio::SocketDescriptor;
 use lightning_persister::FilesystemPersister;
+use lightning_rapid_gossip_sync::RapidGossipSync;
 use rand::{thread_rng, Rng};
 use std::collections::hash_map::Entry;
 use std::collections::HashMap;
@@ -48,10 +50,9 @@ use std::io;
 use std::io::Write;
 use std::ops::Deref;
 use std::path::Path;
+use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::{Arc, Mutex};
 use std::time::{Duration, SystemTime};
-use tokio::sync::mpsc;
-use tokio::sync::mpsc::Receiver;
 
 pub(crate) enum HTLCStatus {
        Pending,
@@ -100,167 +101,273 @@ pub(crate) type PeerManager = SimpleArcPeerManager<
 pub(crate) type ChannelManager =
        SimpleArcChannelManager<ChainMonitor, BitcoindClient, BitcoindClient, FilesystemLogger>;
 
+pub(crate) type InvoicePayer<E> = payment::InvoicePayer<
+       Arc<ChannelManager>,
+       Router,
+       Arc<Mutex<ProbabilisticScorer<Arc<NetworkGraph>, Arc<FilesystemLogger>>>>,
+       Arc<FilesystemLogger>,
+       E,
+>;
+
+type Router = DefaultRouter<Arc<NetworkGraph>, Arc<FilesystemLogger>>;
+
+type GossipSync<P, G, A, L> =
+       lightning_background_processor::GossipSync<P, Arc<RapidGossipSync<G, L>>, G, A, L>;
+
+pub(crate) type NetworkGraph = gossip::NetworkGraph<Arc<FilesystemLogger>>;
+
+struct NodeAlias<'a>(&'a [u8; 32]);
+
+impl fmt::Display for NodeAlias<'_> {
+       fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+               let alias = self
+                       .0
+                       .iter()
+                       .map(|b| *b as char)
+                       .take_while(|c| *c != '\0')
+                       .filter(|c| c.is_ascii_graphic() || *c == ' ')
+                       .collect::<String>();
+               write!(f, "{}", alias)
+       }
+}
+
 async fn handle_ldk_events(
-       channel_manager: Arc<ChannelManager>, chain_monitor: Arc<ChainMonitor>,
-       bitcoind_client: Arc<BitcoindClient>, keys_manager: Arc<KeysManager>,
+       channel_manager: Arc<ChannelManager>, bitcoind_client: Arc<BitcoindClient>,
+       network_graph: Arc<NetworkGraph>, keys_manager: Arc<KeysManager>,
        inbound_payments: PaymentInfoStorage, outbound_payments: PaymentInfoStorage, network: Network,
-       mut event_receiver: Receiver<()>,
+       event: &Event,
 ) {
-       loop {
-               let received = event_receiver.recv();
-               if received.await.is_none() {
-                       println!("LDK Event channel closed!");
-                       return;
+       match event {
+               Event::FundingGenerationReady {
+                       temporary_channel_id,
+                       counterparty_node_id,
+                       channel_value_satoshis,
+                       output_script,
+                       ..
+               } => {
+                       // Construct the raw transaction with one output, that is paid the amount of the
+                       // channel.
+                       let addr = WitnessProgram::from_scriptpubkey(
+                               &output_script[..],
+                               match network {
+                                       Network::Bitcoin => bitcoin_bech32::constants::Network::Bitcoin,
+                                       Network::Testnet => bitcoin_bech32::constants::Network::Testnet,
+                                       Network::Regtest => bitcoin_bech32::constants::Network::Regtest,
+                                       Network::Signet => bitcoin_bech32::constants::Network::Signet,
+                               },
+                       )
+                       .expect("Lightning funding tx should always be to a SegWit output")
+                       .to_address();
+                       let mut outputs = vec![HashMap::with_capacity(1)];
+                       outputs[0].insert(addr, *channel_value_satoshis as f64 / 100_000_000.0);
+                       let raw_tx = bitcoind_client.create_raw_transaction(outputs).await;
+
+                       // Have your wallet put the inputs into the transaction such that the output is
+                       // satisfied.
+                       let funded_tx = bitcoind_client.fund_raw_transaction(raw_tx).await;
+
+                       // Sign the final funding transaction and broadcast it.
+                       let signed_tx = bitcoind_client.sign_raw_transaction_with_wallet(funded_tx.hex).await;
+                       assert_eq!(signed_tx.complete, true);
+                       let final_tx: Transaction =
+                               encode::deserialize(&hex_utils::to_vec(&signed_tx.hex).unwrap()).unwrap();
+                       // Give the funding transaction back to LDK for opening the channel.
+                       if channel_manager
+                               .funding_transaction_generated(
+                                       &temporary_channel_id,
+                                       counterparty_node_id,
+                                       final_tx,
+                               )
+                               .is_err()
+                       {
+                               println!(
+                                       "\nERROR: Channel went away before we could fund it. The peer disconnected or refused the channel.");
+                               print!("> ");
+                               io::stdout().flush().unwrap();
+                       }
                }
-               let loop_channel_manager = channel_manager.clone();
-               let mut events = channel_manager.get_and_clear_pending_events();
-               events.append(&mut chain_monitor.get_and_clear_pending_events());
-               for event in events {
-                       match event {
-                               Event::FundingGenerationReady {
-                                       temporary_channel_id,
-                                       channel_value_satoshis,
-                                       output_script,
-                                       ..
-                               } => {
-                                       // Construct the raw transaction with one output, that is paid the amount of the
-                                       // channel.
-                                       let addr = WitnessProgram::from_scriptpubkey(
-                                               &output_script[..],
-                                               match network {
-                                                       Network::Bitcoin => bitcoin_bech32::constants::Network::Bitcoin,
-                                                       Network::Testnet => bitcoin_bech32::constants::Network::Testnet,
-                                                       Network::Regtest => bitcoin_bech32::constants::Network::Regtest,
-                                                       Network::Signet => panic!("Signet unsupported"),
-                                               },
-                                       )
-                                       .expect("Lightning funding tx should always be to a SegWit output")
-                                       .to_address();
-                                       let mut outputs = vec![HashMap::with_capacity(1)];
-                                       outputs[0].insert(addr, channel_value_satoshis as f64 / 100_000_000.0);
-                                       let raw_tx = bitcoind_client.create_raw_transaction(outputs).await;
-
-                                       // Have your wallet put the inputs into the transaction such that the output is
-                                       // satisfied.
-                                       let funded_tx = bitcoind_client.fund_raw_transaction(raw_tx).await;
-                                       let change_output_position = funded_tx.changepos;
-                                       assert!(change_output_position == 0 || change_output_position == 1);
-
-                                       // Sign the final funding transaction and broadcast it.
-                                       let signed_tx =
-                                               bitcoind_client.sign_raw_transaction_with_wallet(funded_tx.hex).await;
-                                       assert_eq!(signed_tx.complete, true);
-                                       let final_tx: Transaction =
-                                               encode::deserialize(&hex_utils::to_vec(&signed_tx.hex).unwrap()).unwrap();
-                                       // Give the funding transaction back to LDK for opening the channel.
-                                       loop_channel_manager
-                                               .funding_transaction_generated(&temporary_channel_id, final_tx)
-                                               .unwrap();
+               Event::PaymentReceived { payment_hash, purpose, amount_msat } => {
+                       println!(
+                               "\nEVENT: received payment from payment hash {} of {} millisatoshis",
+                               hex_utils::hex_str(&payment_hash.0),
+                               amount_msat,
+                       );
+                       print!("> ");
+                       io::stdout().flush().unwrap();
+                       let payment_preimage = match purpose {
+                               PaymentPurpose::InvoicePayment { payment_preimage, .. } => *payment_preimage,
+                               PaymentPurpose::SpontaneousPayment(preimage) => Some(*preimage),
+                       };
+                       channel_manager.claim_funds(payment_preimage.unwrap());
+               }
+               Event::PaymentClaimed { payment_hash, purpose, amount_msat } => {
+                       println!(
+                               "\nEVENT: claimed payment from payment hash {} of {} millisatoshis",
+                               hex_utils::hex_str(&payment_hash.0),
+                               amount_msat,
+                       );
+                       print!("> ");
+                       io::stdout().flush().unwrap();
+                       let (payment_preimage, payment_secret) = match purpose {
+                               PaymentPurpose::InvoicePayment { payment_preimage, payment_secret, .. } => {
+                                       (*payment_preimage, Some(*payment_secret))
                                }
-                               Event::PaymentReceived {
-                                       payment_hash,
-                                       payment_preimage,
-                                       payment_secret,
-                                       amt,
-                                       ..
-                               } => {
-                                       let mut payments = inbound_payments.lock().unwrap();
-                                       let status = match loop_channel_manager.claim_funds(payment_preimage.unwrap()) {
-                                               true => {
-                                                       println!(
-                                                               "\nEVENT: received payment from payment hash {} of {} millisatoshis",
-                                                               hex_utils::hex_str(&payment_hash.0),
-                                                               amt
-                                                       );
-                                                       print!("> ");
-                                                       io::stdout().flush().unwrap();
-                                                       HTLCStatus::Succeeded
-                                               }
-                                               _ => HTLCStatus::Failed,
-                                       };
-                                       match payments.entry(payment_hash) {
-                                               Entry::Occupied(mut e) => {
-                                                       let payment = e.get_mut();
-                                                       payment.status = status;
-                                                       payment.preimage = Some(payment_preimage.unwrap());
-                                                       payment.secret = Some(payment_secret);
-                                               }
-                                               Entry::Vacant(e) => {
-                                                       e.insert(PaymentInfo {
-                                                               preimage: Some(payment_preimage.unwrap()),
-                                                               secret: Some(payment_secret),
-                                                               status,
-                                                               amt_msat: MillisatAmount(Some(amt)),
-                                                       });
-                                               }
-                                       }
+                               PaymentPurpose::SpontaneousPayment(preimage) => (Some(*preimage), None),
+                       };
+                       let mut payments = inbound_payments.lock().unwrap();
+                       match payments.entry(*payment_hash) {
+                               Entry::Occupied(mut e) => {
+                                       let payment = e.get_mut();
+                                       payment.status = HTLCStatus::Succeeded;
+                                       payment.preimage = payment_preimage;
+                                       payment.secret = payment_secret;
                                }
-                               Event::PaymentSent { payment_preimage } => {
-                                       let hashed = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
-                                       let mut payments = outbound_payments.lock().unwrap();
-                                       for (payment_hash, payment) in payments.iter_mut() {
-                                               if *payment_hash == hashed {
-                                                       payment.preimage = Some(payment_preimage);
-                                                       payment.status = HTLCStatus::Succeeded;
-                                                       println!(
-                                                               "\nEVENT: successfully sent payment of {} millisatoshis from \
-                                         payment hash {:?} with preimage {:?}",
-                                                               payment.amt_msat,
-                                                               hex_utils::hex_str(&payment_hash.0),
-                                                               hex_utils::hex_str(&payment_preimage.0)
-                                                       );
-                                                       print!("> ");
-                                                       io::stdout().flush().unwrap();
-                                               }
-                                       }
+                               Entry::Vacant(e) => {
+                                       e.insert(PaymentInfo {
+                                               preimage: payment_preimage,
+                                               secret: payment_secret,
+                                               status: HTLCStatus::Succeeded,
+                                               amt_msat: MillisatAmount(Some(*amount_msat)),
+                                       });
                                }
-                               Event::PaymentFailed { payment_hash, rejected_by_dest } => {
-                                       print!(
-                                               "\nEVENT: Failed to send payment to payment hash {:?}: ",
-                                               hex_utils::hex_str(&payment_hash.0)
+                       }
+               }
+               Event::PaymentSent { payment_preimage, payment_hash, fee_paid_msat, .. } => {
+                       let mut payments = outbound_payments.lock().unwrap();
+                       for (hash, payment) in payments.iter_mut() {
+                               if *hash == *payment_hash {
+                                       payment.preimage = Some(*payment_preimage);
+                                       payment.status = HTLCStatus::Succeeded;
+                                       println!(
+                                               "\nEVENT: successfully sent payment of {} millisatoshis{} from \
+                                                                payment hash {:?} with preimage {:?}",
+                                               payment.amt_msat,
+                                               if let Some(fee) = fee_paid_msat {
+                                                       format!(" (fee {} msat)", fee)
+                                               } else {
+                                                       "".to_string()
+                                               },
+                                               hex_utils::hex_str(&payment_hash.0),
+                                               hex_utils::hex_str(&payment_preimage.0)
                                        );
-                                       if rejected_by_dest {
-                                               println!("re-attempting the payment will not succeed");
-                                       } else {
-                                               println!("payment may be retried");
-                                       }
                                        print!("> ");
                                        io::stdout().flush().unwrap();
+                               }
+                       }
+               }
+               Event::OpenChannelRequest { .. } => {
+                       // Unreachable, we don't set manually_accept_inbound_channels
+               }
+               Event::PaymentPathSuccessful { .. } => {}
+               Event::PaymentPathFailed { .. } => {}
+               Event::PaymentFailed { payment_hash, .. } => {
+                       print!(
+                               "\nEVENT: Failed to send payment to payment hash {:?}: exhausted payment retry attempts",
+                               hex_utils::hex_str(&payment_hash.0)
+                       );
+                       print!("> ");
+                       io::stdout().flush().unwrap();
 
-                                       let mut payments = outbound_payments.lock().unwrap();
-                                       if payments.contains_key(&payment_hash) {
-                                               let payment = payments.get_mut(&payment_hash).unwrap();
-                                               payment.status = HTLCStatus::Failed;
+                       let mut payments = outbound_payments.lock().unwrap();
+                       if payments.contains_key(&payment_hash) {
+                               let payment = payments.get_mut(&payment_hash).unwrap();
+                               payment.status = HTLCStatus::Failed;
+                       }
+               }
+               Event::PaymentForwarded {
+                       prev_channel_id,
+                       next_channel_id,
+                       fee_earned_msat,
+                       claim_from_onchain_tx,
+               } => {
+                       let read_only_network_graph = network_graph.read_only();
+                       let nodes = read_only_network_graph.nodes();
+                       let channels = channel_manager.list_channels();
+
+                       let node_str = |channel_id: &Option<[u8; 32]>| match channel_id {
+                               None => String::new(),
+                               Some(channel_id) => match channels.iter().find(|c| c.channel_id == *channel_id) {
+                                       None => String::new(),
+                                       Some(channel) => {
+                                               match nodes.get(&NodeId::from_pubkey(&channel.counterparty.node_id)) {
+                                                       None => " from private node".to_string(),
+                                                       Some(node) => match &node.announcement_info {
+                                                               None => " from unnamed node".to_string(),
+                                                               Some(announcement) => {
+                                                                       format!(" from node {}", NodeAlias(&announcement.alias))
+                                                               }
+                                                       },
+                                               }
                                        }
-                               }
-                               Event::PendingHTLCsForwardable { time_forwardable } => {
-                                       let forwarding_channel_manager = loop_channel_manager.clone();
-                                       tokio::spawn(async move {
-                                               let min = time_forwardable.as_millis() as u64;
-                                               let millis_to_sleep = thread_rng().gen_range(min, min * 5) as u64;
-                                               tokio::time::sleep(Duration::from_millis(millis_to_sleep)).await;
-                                               forwarding_channel_manager.process_pending_htlc_forwards();
-                                       });
-                               }
-                               Event::SpendableOutputs { outputs } => {
-                                       let destination_address = bitcoind_client.get_new_address().await;
-                                       let output_descriptors = &outputs.iter().map(|a| a).collect::<Vec<_>>();
-                                       let tx_feerate =
-                                               bitcoind_client.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
-                                       let spending_tx = keys_manager
-                                               .spend_spendable_outputs(
-                                                       output_descriptors,
-                                                       Vec::new(),
-                                                       destination_address.script_pubkey(),
-                                                       tx_feerate,
-                                                       &Secp256k1::new(),
-                                               )
-                                               .unwrap();
-                                       bitcoind_client.broadcast_transaction(&spending_tx);
-                               }
+                               },
+                       };
+                       let channel_str = |channel_id: &Option<[u8; 32]>| {
+                               channel_id
+                                       .map(|channel_id| format!(" with channel {}", hex_utils::hex_str(&channel_id)))
+                                       .unwrap_or_default()
+                       };
+                       let from_prev_str =
+                               format!("{}{}", node_str(prev_channel_id), channel_str(prev_channel_id));
+                       let to_next_str =
+                               format!("{}{}", node_str(next_channel_id), channel_str(next_channel_id));
+
+                       let from_onchain_str = if *claim_from_onchain_tx {
+                               "from onchain downstream claim"
+                       } else {
+                               "from HTLC fulfill message"
+                       };
+                       if let Some(fee_earned) = fee_earned_msat {
+                               println!(
+                                       "\nEVENT: Forwarded payment{}{}, earning {} msat {}",
+                                       from_prev_str, to_next_str, fee_earned, from_onchain_str
+                               );
+                       } else {
+                               println!(
+                                       "\nEVENT: Forwarded payment{}{}, claiming onchain {}",
+                                       from_prev_str, to_next_str, from_onchain_str
+                               );
                        }
+                       print!("> ");
+                       io::stdout().flush().unwrap();
+               }
+               Event::PendingHTLCsForwardable { time_forwardable } => {
+                       let forwarding_channel_manager = channel_manager.clone();
+                       let min = time_forwardable.as_millis() as u64;
+                       tokio::spawn(async move {
+                               let millis_to_sleep = thread_rng().gen_range(min, min * 5) as u64;
+                               tokio::time::sleep(Duration::from_millis(millis_to_sleep)).await;
+                               forwarding_channel_manager.process_pending_htlc_forwards();
+                       });
+               }
+               Event::SpendableOutputs { outputs } => {
+                       let destination_address = bitcoind_client.get_new_address().await;
+                       let output_descriptors = &outputs.iter().map(|a| a).collect::<Vec<_>>();
+                       let tx_feerate =
+                               bitcoind_client.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
+                       let spending_tx = keys_manager
+                               .spend_spendable_outputs(
+                                       output_descriptors,
+                                       Vec::new(),
+                                       destination_address.script_pubkey(),
+                                       tx_feerate,
+                                       &Secp256k1::new(),
+                               )
+                               .unwrap();
+                       bitcoind_client.broadcast_transaction(&spending_tx);
+               }
+               Event::ChannelClosed { channel_id, reason, user_channel_id: _ } => {
+                       println!(
+                               "\nEVENT: Channel {} closed due to: {:?}",
+                               hex_utils::hex_str(channel_id),
+                               reason
+                       );
+                       print!("> ");
+                       io::stdout().flush().unwrap();
+               }
+               Event::DiscardFunding { .. } => {
+                       // A "real" node should probably "lock" the UTXOs spent in funding transactions until
+                       // the funding transaction either confirms, or this event is generated.
                }
-               tokio::time::sleep(Duration::from_secs(1)).await;
        }
 }
 
@@ -280,6 +387,7 @@ async fn start_ldk() {
                args.bitcoind_rpc_port,
                args.bitcoind_rpc_username.clone(),
                args.bitcoind_rpc_password.clone(),
+               tokio::runtime::Handle::current(),
        )
        .await
        {
@@ -365,9 +473,10 @@ async fn start_ldk() {
        let mut channelmonitors = persister.read_channelmonitors(keys_manager.clone()).unwrap();
 
        // Step 8: Initialize the ChannelManager
-       let user_config = UserConfig::default();
+       let mut user_config = UserConfig::default();
+       user_config.peer_channel_config_limits.force_announced_channel_preference = false;
        let mut restarting_node = true;
-       let (channel_manager_blockhash, mut channel_manager) = {
+       let (channel_manager_blockhash, channel_manager) = {
                if let Ok(mut f) = fs::File::open(format!("{}/manager", ldk_data_dir.clone())) {
                        let mut channel_monitor_mut_references = Vec::new();
                        for (_, channel_monitor) in channelmonitors.iter_mut() {
@@ -414,7 +523,7 @@ async fn start_ldk() {
        let mut chain_tip: Option<poll::ValidatedBlockHeader> = None;
        if restarting_node {
                let mut chain_listeners =
-                       vec![(channel_manager_blockhash, &mut channel_manager as &mut dyn chain::Listen)];
+                       vec![(channel_manager_blockhash, &channel_manager as &dyn chain::Listen)];
 
                for (blockhash, channel_monitor) in channelmonitors.drain(..) {
                        let outpoint = channel_monitor.get_funding_txo().0;
@@ -426,10 +535,8 @@ async fn start_ldk() {
                }
 
                for monitor_listener_info in chain_listener_channel_monitors.iter_mut() {
-                       chain_listeners.push((
-                               monitor_listener_info.0,
-                               &mut monitor_listener_info.1 as &mut dyn chain::Listen,
-                       ));
+                       chain_listeners
+                               .push((monitor_listener_info.0, &monitor_listener_info.1 as &dyn chain::Listen));
                }
                chain_tip = Some(
                        init::synchronize_listeners(
@@ -450,11 +557,13 @@ async fn start_ldk() {
                chain_monitor.watch_channel(funding_outpoint, channel_monitor).unwrap();
        }
 
-       // Step 11: Optional: Initialize the NetGraphMsgHandler
-       // XXX persist routing data
+       // Step 11: Optional: Initialize the P2PGossipSync
        let genesis = genesis_block(args.network).header.block_hash();
-       let router = Arc::new(NetGraphMsgHandler::new(
-               genesis,
+       let network_graph_path = format!("{}/network_graph", ldk_data_dir.clone());
+       let network_graph =
+               Arc::new(disk::read_network(Path::new(&network_graph_path), genesis, logger.clone()));
+       let gossip_sync = Arc::new(P2PGossipSync::new(
+               Arc::clone(&network_graph),
                None::<Arc<dyn chain::Access + Send + Sync>>,
                logger.clone(),
        ));
@@ -463,36 +572,38 @@ async fn start_ldk() {
        let channel_manager: Arc<ChannelManager> = Arc::new(channel_manager);
        let mut ephemeral_bytes = [0; 32];
        rand::thread_rng().fill_bytes(&mut ephemeral_bytes);
-       let lightning_msg_handler =
-               MessageHandler { chan_handler: channel_manager.clone(), route_handler: router.clone() };
+       let lightning_msg_handler = MessageHandler {
+               chan_handler: channel_manager.clone(),
+               route_handler: gossip_sync.clone(),
+       };
        let peer_manager: Arc<PeerManager> = Arc::new(PeerManager::new(
                lightning_msg_handler,
-               keys_manager.get_node_secret(),
+               keys_manager.get_node_secret(Recipient::Node).unwrap(),
                &ephemeral_bytes,
                logger.clone(),
+               Arc::new(IgnoringMessageHandler {}),
        ));
 
        // ## Running LDK
        // Step 13: Initialize networking
 
-       // We poll for events in handle_ldk_events(..) rather than waiting for them over the
-       // mpsc::channel, so we can leave the event receiver as unused.
-       let (event_ntfn_sender, event_ntfn_receiver) = mpsc::channel(2);
        let peer_manager_connection_handler = peer_manager.clone();
-       let event_notifier = event_ntfn_sender.clone();
        let listening_port = args.ldk_peer_listening_port;
+       let stop_listen_connect = Arc::new(AtomicBool::new(false));
+       let stop_listen = Arc::clone(&stop_listen_connect);
        tokio::spawn(async move {
                let listener = tokio::net::TcpListener::bind(format!("0.0.0.0:{}", listening_port))
                        .await
                        .expect("Failed to bind to listen port - is something else already listening on it?");
                loop {
                        let peer_mgr = peer_manager_connection_handler.clone();
-                       let notifier = event_notifier.clone();
                        let tcp_stream = listener.accept().await.unwrap().0;
+                       if stop_listen.load(Ordering::Acquire) {
+                               return;
+                       }
                        tokio::spawn(async move {
                                lightning_net_tokio::setup_inbound(
                                        peer_mgr.clone(),
-                                       notifier.clone(),
                                        tcp_stream.into_std().unwrap(),
                                )
                                .await;
@@ -521,9 +632,8 @@ async fn start_ldk() {
                }
        });
 
-       // Step 15: Initialize LDK Event Handling
+       // Step 15: Handle LDK Events
        let channel_manager_event_listener = channel_manager.clone();
-       let chain_monitor_event_listener = chain_monitor.clone();
        let keys_manager_listener = keys_manager.clone();
        // TODO: persist payment info to disk
        let inbound_payments: PaymentInfoStorage = Arc::new(Mutex::new(HashMap::new()));
@@ -532,50 +642,96 @@ async fn start_ldk() {
        let outbound_pmts_for_events = outbound_payments.clone();
        let network = args.network;
        let bitcoind_rpc = bitcoind_client.clone();
-       tokio::spawn(async move {
-               handle_ldk_events(
-                       channel_manager_event_listener,
-                       chain_monitor_event_listener,
-                       bitcoind_rpc,
-                       keys_manager_listener,
-                       inbound_pmts_for_events,
-                       outbound_pmts_for_events,
+       let network_graph_events = network_graph.clone();
+       let handle = tokio::runtime::Handle::current();
+       let event_handler = move |event: &Event| {
+               handle.block_on(handle_ldk_events(
+                       channel_manager_event_listener.clone(),
+                       bitcoind_rpc.clone(),
+                       network_graph_events.clone(),
+                       keys_manager_listener.clone(),
+                       inbound_pmts_for_events.clone(),
+                       outbound_pmts_for_events.clone(),
                        network,
-                       event_ntfn_receiver,
-               )
-               .await;
-       });
+                       event,
+               ));
+       };
+
+       // Step 16: Initialize routing ProbabilisticScorer
+       let scorer_path = format!("{}/scorer", ldk_data_dir.clone());
+       let scorer = Arc::new(Mutex::new(disk::read_scorer(
+               Path::new(&scorer_path),
+               Arc::clone(&network_graph),
+               Arc::clone(&logger),
+       )));
+
+       // Step 17: Create InvoicePayer
+       let router = DefaultRouter::new(
+               network_graph.clone(),
+               logger.clone(),
+               keys_manager.get_secure_random_bytes(),
+       );
+       let invoice_payer = Arc::new(InvoicePayer::new(
+               channel_manager.clone(),
+               router,
+               scorer.clone(),
+               logger.clone(),
+               event_handler,
+               payment::Retry::Attempts(5),
+       ));
 
-       // Step 16 & 17: Persist ChannelManager & Background Processing
-       let data_dir = ldk_data_dir.clone();
-       let persist_channel_manager_callback =
-               move |node: &ChannelManager| FilesystemPersister::persist_manager(data_dir.clone(), &*node);
-       BackgroundProcessor::start(
-               persist_channel_manager_callback,
+       // Step 18: Persist ChannelManager and NetworkGraph
+       let persister = Arc::new(FilesystemPersister::new(ldk_data_dir.clone()));
+
+       // Step 19: Background Processing
+       let background_processor = BackgroundProcessor::start(
+               persister,
+               invoice_payer.clone(),
+               chain_monitor.clone(),
                channel_manager.clone(),
+               GossipSync::P2P(gossip_sync.clone()),
                peer_manager.clone(),
                logger.clone(),
+               Some(scorer.clone()),
        );
 
-       // Reconnect to channel peers if possible.
+       // Regularly reconnect to channel peers.
+       let connect_cm = Arc::clone(&channel_manager);
+       let connect_pm = Arc::clone(&peer_manager);
        let peer_data_path = format!("{}/channel_peer_data", ldk_data_dir.clone());
-       match disk::read_channel_peer_data(Path::new(&peer_data_path)) {
-               Ok(mut info) => {
-                       for (pubkey, peer_addr) in info.drain() {
-                               for chan_info in channel_manager.list_channels() {
-                                       if pubkey == chan_info.remote_network_id {
-                                               let _ = cli::connect_peer_if_necessary(
-                                                       pubkey,
-                                                       peer_addr,
-                                                       peer_manager.clone(),
-                                                       event_ntfn_sender.clone(),
-                                               );
+       let stop_connect = Arc::clone(&stop_listen_connect);
+       tokio::spawn(async move {
+               let mut interval = tokio::time::interval(Duration::from_secs(1));
+               loop {
+                       interval.tick().await;
+                       match disk::read_channel_peer_data(Path::new(&peer_data_path)) {
+                               Ok(info) => {
+                                       let peers = connect_pm.get_peer_node_ids();
+                                       for node_id in connect_cm
+                                               .list_channels()
+                                               .iter()
+                                               .map(|chan| chan.counterparty.node_id)
+                                               .filter(|id| !peers.contains(id))
+                                       {
+                                               if stop_connect.load(Ordering::Acquire) {
+                                                       return;
+                                               }
+                                               for (pubkey, peer_addr) in info.iter() {
+                                                       if *pubkey == node_id {
+                                                               let _ = cli::do_connect_peer(
+                                                                       *pubkey,
+                                                                       peer_addr.clone(),
+                                                                       Arc::clone(&connect_pm),
+                                                               )
+                                                               .await;
+                                                       }
+                                               }
                                        }
                                }
+                               Err(e) => println!("ERROR: errored reading channel peer info from disk: {:?}", e),
                        }
                }
-               Err(e) => println!("ERROR: errored reading channel peer info from disk: {:?}", e),
-       }
+       });
 
        // Regularly broadcast our node_announcement. This is only required (or possible) if we have
        // some public channels, and is only useful if we have public listen address(es) to announce.
@@ -583,7 +739,7 @@ async fn start_ldk() {
        // to avoid churn in the global network graph.
        let chan_manager = Arc::clone(&channel_manager);
        let network = args.network;
-       if args.ldk_announced_listen_addr.is_some() {
+       if !args.ldk_announced_listen_addr.is_empty() {
                tokio::spawn(async move {
                        let mut interval = tokio::time::interval(Duration::from_secs(60));
                        loop {
@@ -591,7 +747,7 @@ async fn start_ldk() {
                                chan_manager.broadcast_node_announcement(
                                        [0; 3],
                                        args.ldk_announced_node_name,
-                                       vec![args.ldk_announced_listen_addr.as_ref().unwrap().clone()],
+                                       args.ldk_announced_listen_addr.clone(),
                                );
                        }
                });
@@ -599,18 +755,25 @@ async fn start_ldk() {
 
        // Start the CLI.
        cli::poll_for_user_input(
-               peer_manager.clone(),
-               channel_manager.clone(),
-               keys_manager.clone(),
-               router.clone(),
+               Arc::clone(&invoice_payer),
+               Arc::clone(&peer_manager),
+               Arc::clone(&channel_manager),
+               Arc::clone(&keys_manager),
+               Arc::clone(&network_graph),
                inbound_payments,
                outbound_payments,
-               event_ntfn_sender,
                ldk_data_dir.clone(),
-               logger.clone(),
                network,
        )
        .await;
+
+       // Disconnect our peers and stop accepting new connections. This ensures we don't continue
+       // updating our channel data after we've stopped the background processor.
+       stop_listen_connect.store(true, Ordering::Release);
+       peer_manager.disconnect_all_peers();
+
+       // Stop the background processor.
+       background_processor.stop().unwrap();
 }
 
 #[tokio::main]