_ Git - ldk-sample/blob - src/main.rs

   1 pub mod bitcoind_client;
   2 mod cli;
   3 mod convert;
   4 mod disk;
   5 mod hex_utils;
   6
   7 use crate::bitcoind_client::BitcoindClient;
   8 use crate::disk::FilesystemLogger;
   9 use bitcoin::blockdata::constants::genesis_block;
  10 use bitcoin::blockdata::transaction::Transaction;
  11 use bitcoin::consensus::encode;
  12 use bitcoin::network::constants::Network;
  13 use bitcoin::secp256k1::Secp256k1;
  14 use bitcoin::BlockHash;
  15 use bitcoin_bech32::WitnessProgram;
  16 use lightning::chain;
  17 use lightning::chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, FeeEstimator};
  18 use lightning::chain::chainmonitor;
  19 use lightning::chain::keysinterface::{InMemorySigner, KeysInterface, KeysManager, Recipient};
  20 use lightning::chain::{BestBlock, Filter, Watch};
  21 use lightning::ln::channelmanager;
  22 use lightning::ln::channelmanager::{
  23         ChainParameters, ChannelManagerReadArgs, SimpleArcChannelManager,
  24 };
  25 use lightning::ln::peer_handler::{IgnoringMessageHandler, MessageHandler, SimpleArcPeerManager};
  26 use lightning::ln::{PaymentHash, PaymentPreimage, PaymentSecret};
  27 use lightning::routing::network_graph::{NetGraphMsgHandler, NetworkGraph};
  28 use lightning::routing::scoring::ProbabilisticScorer;
  29 use lightning::util::config::UserConfig;
  30 use lightning::util::events::{Event, PaymentPurpose};
  31 use lightning::util::ser::ReadableArgs;
  32 use lightning_background_processor::BackgroundProcessor;
  33 use lightning_block_sync::init;
  34 use lightning_block_sync::poll;
  35 use lightning_block_sync::SpvClient;
  36 use lightning_block_sync::UnboundedCache;
  37 use lightning_invoice::payment;
  38 use lightning_invoice::utils::DefaultRouter;
  39 use lightning_net_tokio::SocketDescriptor;
  40 use lightning_persister::FilesystemPersister;
  41 use rand::{thread_rng, Rng};
  42 use std::collections::hash_map::Entry;
  43 use std::collections::HashMap;
  44 use std::fmt;
  45 use std::fs;
  46 use std::fs::File;
  47 use std::io;
  48 use std::io::Write;
  49 use std::ops::Deref;
  50 use std::path::Path;
  51 use std::sync::atomic::{AtomicBool, Ordering};
  52 use std::sync::{Arc, Mutex};
  53 use std::time::{Duration, SystemTime};
  54
  55 pub(crate) enum HTLCStatus {
  56         Pending,
  57         Succeeded,
  58         Failed,
  59 }
  60
  61 pub(crate) struct MillisatAmount(Option<u64>);
  62
  63 impl fmt::Display for MillisatAmount {
  64         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
  65                 match self.0 {
  66                         Some(amt) => write!(f, "{}", amt),
  67                         None => write!(f, "unknown"),
  68                 }
  69         }
  70 }
  71
  72 pub(crate) struct PaymentInfo {
  73         preimage: Option<PaymentPreimage>,
  74         secret: Option<PaymentSecret>,
  75         status: HTLCStatus,
  76         amt_msat: MillisatAmount,
  77 }
  78
  79 pub(crate) type PaymentInfoStorage = Arc<Mutex<HashMap<PaymentHash, PaymentInfo>>>;
  80
  81 type ChainMonitor = chainmonitor::ChainMonitor<
  82         InMemorySigner,
  83         Arc<dyn Filter + Send + Sync>,
  84         Arc<BitcoindClient>,
  85         Arc<BitcoindClient>,
  86         Arc<FilesystemLogger>,
  87         Arc<FilesystemPersister>,
  88 >;
  89
  90 pub(crate) type PeerManager = SimpleArcPeerManager<
  91         SocketDescriptor,
  92         ChainMonitor,
  93         BitcoindClient,
  94         BitcoindClient,
  95         dyn chain::Access + Send + Sync,
  96         FilesystemLogger,
  97 >;
  98
  99 pub(crate) type ChannelManager =
 100         SimpleArcChannelManager<ChainMonitor, BitcoindClient, BitcoindClient, FilesystemLogger>;
 101
 102 pub(crate) type InvoicePayer<E> = payment::InvoicePayer<
 103         Arc<ChannelManager>,
 104         Router,
 105         Arc<Mutex<ProbabilisticScorer<Arc<NetworkGraph>>>>,
 106         Arc<FilesystemLogger>,
 107         E,
 108 >;
 109
 110 type Router = DefaultRouter<Arc<NetworkGraph>, Arc<FilesystemLogger>>;
 111
 112 async fn handle_ldk_events(
 113         channel_manager: Arc<ChannelManager>, bitcoind_client: Arc<BitcoindClient>,
 114         keys_manager: Arc<KeysManager>, inbound_payments: PaymentInfoStorage,
 115         outbound_payments: PaymentInfoStorage, network: Network, event: &Event,
 116 ) {
 117         match event {
 118                 Event::FundingGenerationReady {
 119                         temporary_channel_id,
 120                         channel_value_satoshis,
 121                         output_script,
 122                         ..
 123                 } => {
 124                         // Construct the raw transaction with one output, that is paid the amount of the
 125                         // channel.
 126                         let addr = WitnessProgram::from_scriptpubkey(
 127                                 &output_script[..],
 128                                 match network {
 129                                         Network::Bitcoin => bitcoin_bech32::constants::Network::Bitcoin,
 130                                         Network::Testnet => bitcoin_bech32::constants::Network::Testnet,
 131                                         Network::Regtest => bitcoin_bech32::constants::Network::Regtest,
 132                                         Network::Signet => bitcoin_bech32::constants::Network::Signet,
 133                                 },
 134                         )
 135                         .expect("Lightning funding tx should always be to a SegWit output")
 136                         .to_address();
 137                         let mut outputs = vec![HashMap::with_capacity(1)];
 138                         outputs[0].insert(addr, *channel_value_satoshis as f64 / 100_000_000.0);
 139                         let raw_tx = bitcoind_client.create_raw_transaction(outputs).await;
 140
 141                         // Have your wallet put the inputs into the transaction such that the output is
 142                         // satisfied.
 143                         let funded_tx = bitcoind_client.fund_raw_transaction(raw_tx).await;
 144
 145                         // Sign the final funding transaction and broadcast it.
 146                         let signed_tx = bitcoind_client.sign_raw_transaction_with_wallet(funded_tx.hex).await;
 147                         assert_eq!(signed_tx.complete, true);
 148                         let final_tx: Transaction =
 149                                 encode::deserialize(&hex_utils::to_vec(&signed_tx.hex).unwrap()).unwrap();
 150                         // Give the funding transaction back to LDK for opening the channel.
 151                         if channel_manager
 152                                 .funding_transaction_generated(&temporary_channel_id, final_tx)
 153                                 .is_err()
 154                         {
 155                                 println!(
 156                                         "\nERROR: Channel went away before we could fund it. The peer disconnected or refused the channel.");
 157                                 print!("> ");
 158                                 io::stdout().flush().unwrap();
 159                         }
 160                 }
 161                 Event::PaymentReceived { payment_hash, purpose, amt, .. } => {
 162                         let mut payments = inbound_payments.lock().unwrap();
 163                         let (payment_preimage, payment_secret) = match purpose {
 164                                 PaymentPurpose::InvoicePayment { payment_preimage, payment_secret, .. } => {
 165                                         (*payment_preimage, Some(*payment_secret))
 166                                 }
 167                                 PaymentPurpose::SpontaneousPayment(preimage) => (Some(*preimage), None),
 168                         };
 169                         let status = match channel_manager.claim_funds(payment_preimage.unwrap()) {
 170                                 true => {
 171                                         println!(
 172                                                 "\nEVENT: received payment from payment hash {} of {} millisatoshis",
 173                                                 hex_utils::hex_str(&payment_hash.0),
 174                                                 amt
 175                                         );
 176                                         print!("> ");
 177                                         io::stdout().flush().unwrap();
 178                                         HTLCStatus::Succeeded
 179                                 }
 180                                 _ => HTLCStatus::Failed,
 181                         };
 182                         match payments.entry(*payment_hash) {
 183                                 Entry::Occupied(mut e) => {
 184                                         let payment = e.get_mut();
 185                                         payment.status = status;
 186                                         payment.preimage = payment_preimage;
 187                                         payment.secret = payment_secret;
 188                                 }
 189                                 Entry::Vacant(e) => {
 190                                         e.insert(PaymentInfo {
 191                                                 preimage: payment_preimage,
 192                                                 secret: payment_secret,
 193                                                 status,
 194                                                 amt_msat: MillisatAmount(Some(*amt)),
 195                                         });
 196                                 }
 197                         }
 198                 }
 199                 Event::PaymentSent { payment_preimage, payment_hash, fee_paid_msat, .. } => {
 200                         let mut payments = outbound_payments.lock().unwrap();
 201                         for (hash, payment) in payments.iter_mut() {
 202                                 if *hash == *payment_hash {
 203                                         payment.preimage = Some(*payment_preimage);
 204                                         payment.status = HTLCStatus::Succeeded;
 205                                         println!(
 206                                                 "\nEVENT: successfully sent payment of {} millisatoshis{} from \
 207                                                                  payment hash {:?} with preimage {:?}",
 208                                                 payment.amt_msat,
 209                                                 if let Some(fee) = fee_paid_msat {
 210                                                         format!(" (fee {} msat)", fee)
 211                                                 } else {
 212                                                         "".to_string()
 213                                                 },
 214                                                 hex_utils::hex_str(&payment_hash.0),
 215                                                 hex_utils::hex_str(&payment_preimage.0)
 216                                         );
 217                                         print!("> ");
 218                                         io::stdout().flush().unwrap();
 219                                 }
 220                         }
 221                 }
 222                 Event::OpenChannelRequest { .. } => {
 223                         // Unreachable, we don't set manually_accept_inbound_channels
 224                 }
 225                 Event::PaymentPathSuccessful { .. } => {}
 226                 Event::PaymentPathFailed { .. } => {}
 227                 Event::PaymentFailed { payment_hash, .. } => {
 228                         print!(
 229                                 "\nEVENT: Failed to send payment to payment hash {:?}: exhausted payment retry attempts",
 230                                 hex_utils::hex_str(&payment_hash.0)
 231                         );
 232                         print!("> ");
 233                         io::stdout().flush().unwrap();
 234
 235                         let mut payments = outbound_payments.lock().unwrap();
 236                         if payments.contains_key(&payment_hash) {
 237                                 let payment = payments.get_mut(&payment_hash).unwrap();
 238                                 payment.status = HTLCStatus::Failed;
 239                         }
 240                 }
 241                 Event::PaymentForwarded { fee_earned_msat, claim_from_onchain_tx } => {
 242                         let from_onchain_str = if *claim_from_onchain_tx {
 243                                 "from onchain downstream claim"
 244                         } else {
 245                                 "from HTLC fulfill message"
 246                         };
 247                         if let Some(fee_earned) = fee_earned_msat {
 248                                 println!(
 249                                         "\nEVENT: Forwarded payment, earning {} msat {}",
 250                                         fee_earned, from_onchain_str
 251                                 );
 252                         } else {
 253                                 println!("\nEVENT: Forwarded payment, claiming onchain {}", from_onchain_str);
 254                         }
 255                         print!("> ");
 256                         io::stdout().flush().unwrap();
 257                 }
 258                 Event::PendingHTLCsForwardable { time_forwardable } => {
 259                         let forwarding_channel_manager = channel_manager.clone();
 260                         let min = time_forwardable.as_millis() as u64;
 261                         tokio::spawn(async move {
 262                                 let millis_to_sleep = thread_rng().gen_range(min, min * 5) as u64;
 263                                 tokio::time::sleep(Duration::from_millis(millis_to_sleep)).await;
 264                                 forwarding_channel_manager.process_pending_htlc_forwards();
 265                         });
 266                 }
 267                 Event::SpendableOutputs { outputs } => {
 268                         let destination_address = bitcoind_client.get_new_address().await;
 269                         let output_descriptors = &outputs.iter().map(|a| a).collect::<Vec<_>>();
 270                         let tx_feerate =
 271                                 bitcoind_client.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
 272                         let spending_tx = keys_manager
 273                                 .spend_spendable_outputs(
 274                                         output_descriptors,
 275                                         Vec::new(),
 276                                         destination_address.script_pubkey(),
 277                                         tx_feerate,
 278                                         &Secp256k1::new(),
 279                                 )
 280                                 .unwrap();
 281                         bitcoind_client.broadcast_transaction(&spending_tx);
 282                 }
 283                 Event::ChannelClosed { channel_id, reason, user_channel_id: _ } => {
 284                         println!(
 285                                 "\nEVENT: Channel {} closed due to: {:?}",
 286                                 hex_utils::hex_str(channel_id),
 287                                 reason
 288                         );
 289                         print!("> ");
 290                         io::stdout().flush().unwrap();
 291                 }
 292                 Event::DiscardFunding { .. } => {
 293                         // A "real" node should probably "lock" the UTXOs spent in funding transactions until
 294                         // the funding transaction either confirms, or this event is generated.
 295                 }
 296         }
 297 }
 298
 299 async fn start_ldk() {
 300         let args = match cli::parse_startup_args() {
 301                 Ok(user_args) => user_args,
 302                 Err(()) => return,
 303         };
 304
 305         // Initialize the LDK data directory if necessary.
 306         let ldk_data_dir = format!("{}/.ldk", args.ldk_storage_dir_path);
 307         fs::create_dir_all(ldk_data_dir.clone()).unwrap();
 308
 309         // Initialize our bitcoind client.
 310         let bitcoind_client = match BitcoindClient::new(
 311                 args.bitcoind_rpc_host.clone(),
 312                 args.bitcoind_rpc_port,
 313                 args.bitcoind_rpc_username.clone(),
 314                 args.bitcoind_rpc_password.clone(),
 315                 tokio::runtime::Handle::current(),
 316         )
 317         .await
 318         {
 319                 Ok(client) => Arc::new(client),
 320                 Err(e) => {
 321                         println!("Failed to connect to bitcoind client: {}", e);
 322                         return;
 323                 }
 324         };
 325
 326         // Check that the bitcoind we've connected to is running the network we expect
 327         let bitcoind_chain = bitcoind_client.get_blockchain_info().await.chain;
 328         if bitcoind_chain
 329                 != match args.network {
 330                         bitcoin::Network::Bitcoin => "main",
 331                         bitcoin::Network::Testnet => "test",
 332                         bitcoin::Network::Regtest => "regtest",
 333                         bitcoin::Network::Signet => "signet",
 334                 } {
 335                 println!(
 336                         "Chain argument ({}) didn't match bitcoind chain ({})",
 337                         args.network, bitcoind_chain
 338                 );
 339                 return;
 340         }
 341
 342         // ## Setup
 343         // Step 1: Initialize the FeeEstimator
 344
 345         // BitcoindClient implements the FeeEstimator trait, so it'll act as our fee estimator.
 346         let fee_estimator = bitcoind_client.clone();
 347
 348         // Step 2: Initialize the Logger
 349         let logger = Arc::new(FilesystemLogger::new(ldk_data_dir.clone()));
 350
 351         // Step 3: Initialize the BroadcasterInterface
 352
 353         // BitcoindClient implements the BroadcasterInterface trait, so it'll act as our transaction
 354         // broadcaster.
 355         let broadcaster = bitcoind_client.clone();
 356
 357         // Step 4: Initialize Persist
 358         let persister = Arc::new(FilesystemPersister::new(ldk_data_dir.clone()));
 359
 360         // Step 5: Initialize the ChainMonitor
 361         let chain_monitor: Arc<ChainMonitor> = Arc::new(chainmonitor::ChainMonitor::new(
 362                 None,
 363                 broadcaster.clone(),
 364                 logger.clone(),
 365                 fee_estimator.clone(),
 366                 persister.clone(),
 367         ));
 368
 369         // Step 6: Initialize the KeysManager
 370
 371         // The key seed that we use to derive the node privkey (that corresponds to the node pubkey) and
 372         // other secret key material.
 373         let keys_seed_path = format!("{}/keys_seed", ldk_data_dir.clone());
 374         let keys_seed = if let Ok(seed) = fs::read(keys_seed_path.clone()) {
 375                 assert_eq!(seed.len(), 32);
 376                 let mut key = [0; 32];
 377                 key.copy_from_slice(&seed);
 378                 key
 379         } else {
 380                 let mut key = [0; 32];
 381                 thread_rng().fill_bytes(&mut key);
 382                 match File::create(keys_seed_path.clone()) {
 383                         Ok(mut f) => {
 384                                 f.write_all(&key).expect("Failed to write node keys seed to disk");
 385                                 f.sync_all().expect("Failed to sync node keys seed to disk");
 386                         }
 387                         Err(e) => {
 388                                 println!("ERROR: Unable to create keys seed file {}: {}", keys_seed_path, e);
 389                                 return;
 390                         }
 391                 }
 392                 key
 393         };
 394         let cur = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap();
 395         let keys_manager = Arc::new(KeysManager::new(&keys_seed, cur.as_secs(), cur.subsec_nanos()));
 396
 397         // Step 7: Read ChannelMonitor state from disk
 398         let mut channelmonitors = persister.read_channelmonitors(keys_manager.clone()).unwrap();
 399
 400         // Step 8: Initialize the ChannelManager
 401         let mut user_config = UserConfig::default();
 402         user_config.peer_channel_config_limits.force_announced_channel_preference = false;
 403         let mut restarting_node = true;
 404         let (channel_manager_blockhash, channel_manager) = {
 405                 if let Ok(mut f) = fs::File::open(format!("{}/manager", ldk_data_dir.clone())) {
 406                         let mut channel_monitor_mut_references = Vec::new();
 407                         for (_, channel_monitor) in channelmonitors.iter_mut() {
 408                                 channel_monitor_mut_references.push(channel_monitor);
 409                         }
 410                         let read_args = ChannelManagerReadArgs::new(
 411                                 keys_manager.clone(),
 412                                 fee_estimator.clone(),
 413                                 chain_monitor.clone(),
 414                                 broadcaster.clone(),
 415                                 logger.clone(),
 416                                 user_config,
 417                                 channel_monitor_mut_references,
 418                         );
 419                         <(BlockHash, ChannelManager)>::read(&mut f, read_args).unwrap()
 420                 } else {
 421                         // We're starting a fresh node.
 422                         restarting_node = false;
 423                         let getinfo_resp = bitcoind_client.get_blockchain_info().await;
 424
 425                         let chain_params = ChainParameters {
 426                                 network: args.network,
 427                                 best_block: BestBlock::new(
 428                                         getinfo_resp.latest_blockhash,
 429                                         getinfo_resp.latest_height as u32,
 430                                 ),
 431                         };
 432                         let fresh_channel_manager = channelmanager::ChannelManager::new(
 433                                 fee_estimator.clone(),
 434                                 chain_monitor.clone(),
 435                                 broadcaster.clone(),
 436                                 logger.clone(),
 437                                 keys_manager.clone(),
 438                                 user_config,
 439                                 chain_params,
 440                         );
 441                         (getinfo_resp.latest_blockhash, fresh_channel_manager)
 442                 }
 443         };
 444
 445         // Step 9: Sync ChannelMonitors and ChannelManager to chain tip
 446         let mut chain_listener_channel_monitors = Vec::new();
 447         let mut cache = UnboundedCache::new();
 448         let mut chain_tip: Option<poll::ValidatedBlockHeader> = None;
 449         if restarting_node {
 450                 let mut chain_listeners =
 451                         vec![(channel_manager_blockhash, &channel_manager as &dyn chain::Listen)];
 452
 453                 for (blockhash, channel_monitor) in channelmonitors.drain(..) {
 454                         let outpoint = channel_monitor.get_funding_txo().0;
 455                         chain_listener_channel_monitors.push((
 456                                 blockhash,
 457                                 (channel_monitor, broadcaster.clone(), fee_estimator.clone(), logger.clone()),
 458                                 outpoint,
 459                         ));
 460                 }
 461
 462                 for monitor_listener_info in chain_listener_channel_monitors.iter_mut() {
 463                         chain_listeners
 464                                 .push((monitor_listener_info.0, &monitor_listener_info.1 as &dyn chain::Listen));
 465                 }
 466                 chain_tip = Some(
 467                         init::synchronize_listeners(
 468                                 &mut bitcoind_client.deref(),
 469                                 args.network,
 470                                 &mut cache,
 471                                 chain_listeners,
 472                         )
 473                         .await
 474                         .unwrap(),
 475                 );
 476         }
 477
 478         // Step 10: Give ChannelMonitors to ChainMonitor
 479         for item in chain_listener_channel_monitors.drain(..) {
 480                 let channel_monitor = item.1 .0;
 481                 let funding_outpoint = item.2;
 482                 chain_monitor.watch_channel(funding_outpoint, channel_monitor).unwrap();
 483         }
 484
 485         // Step 11: Optional: Initialize the NetGraphMsgHandler
 486         let genesis = genesis_block(args.network).header.block_hash();
 487         let network_graph_path = format!("{}/network_graph", ldk_data_dir.clone());
 488         let network_graph = Arc::new(disk::read_network(Path::new(&network_graph_path), genesis));
 489         let network_gossip = Arc::new(NetGraphMsgHandler::new(
 490                 Arc::clone(&network_graph),
 491                 None::<Arc<dyn chain::Access + Send + Sync>>,
 492                 logger.clone(),
 493         ));
 494         let network_graph_persist = Arc::clone(&network_graph);
 495         tokio::spawn(async move {
 496                 let mut interval = tokio::time::interval(Duration::from_secs(600));
 497                 loop {
 498                         interval.tick().await;
 499                         if disk::persist_network(Path::new(&network_graph_path), &network_graph_persist)
 500                                 .is_err()
 501                         {
 502                                 // Persistence errors here are non-fatal as we can just fetch the routing graph
 503                                 // again later, but they may indicate a disk error which could be fatal elsewhere.
 504                                 eprintln!(
 505                                         "Warning: Failed to persist network graph, check your disk and permissions"
 506                                 );
 507                         }
 508                 }
 509         });
 510
 511         // Step 12: Initialize the PeerManager
 512         let channel_manager: Arc<ChannelManager> = Arc::new(channel_manager);
 513         let mut ephemeral_bytes = [0; 32];
 514         rand::thread_rng().fill_bytes(&mut ephemeral_bytes);
 515         let lightning_msg_handler = MessageHandler {
 516                 chan_handler: channel_manager.clone(),
 517                 route_handler: network_gossip.clone(),
 518         };
 519         let peer_manager: Arc<PeerManager> = Arc::new(PeerManager::new(
 520                 lightning_msg_handler,
 521                 keys_manager.get_node_secret(Recipient::Node).unwrap(),
 522                 &ephemeral_bytes,
 523                 logger.clone(),
 524                 Arc::new(IgnoringMessageHandler {}),
 525         ));
 526
 527         // ## Running LDK
 528         // Step 13: Initialize networking
 529
 530         let peer_manager_connection_handler = peer_manager.clone();
 531         let listening_port = args.ldk_peer_listening_port;
 532         let stop_listen = Arc::new(AtomicBool::new(false));
 533         let stop_listen_ref = Arc::clone(&stop_listen);
 534         tokio::spawn(async move {
 535                 let listener = tokio::net::TcpListener::bind(format!("0.0.0.0:{}", listening_port))
 536                         .await
 537                         .expect("Failed to bind to listen port - is something else already listening on it?");
 538                 loop {
 539                         let peer_mgr = peer_manager_connection_handler.clone();
 540                         let tcp_stream = listener.accept().await.unwrap().0;
 541                         if stop_listen_ref.load(Ordering::Acquire) {
 542                                 return;
 543                         }
 544                         tokio::spawn(async move {
 545                                 lightning_net_tokio::setup_inbound(
 546                                         peer_mgr.clone(),
 547                                         tcp_stream.into_std().unwrap(),
 548                                 )
 549                                 .await;
 550                         });
 551                 }
 552         });
 553
 554         // Step 14: Connect and Disconnect Blocks
 555         if chain_tip.is_none() {
 556                 chain_tip =
 557                         Some(init::validate_best_block_header(&mut bitcoind_client.deref()).await.unwrap());
 558         }
 559         let channel_manager_listener = channel_manager.clone();
 560         let chain_monitor_listener = chain_monitor.clone();
 561         let bitcoind_block_source = bitcoind_client.clone();
 562         let network = args.network;
 563         tokio::spawn(async move {
 564                 let mut derefed = bitcoind_block_source.deref();
 565                 let chain_poller = poll::ChainPoller::new(&mut derefed, network);
 566                 let chain_listener = (chain_monitor_listener, channel_manager_listener);
 567                 let mut spv_client =
 568                         SpvClient::new(chain_tip.unwrap(), chain_poller, &mut cache, &chain_listener);
 569                 loop {
 570                         spv_client.poll_best_tip().await.unwrap();
 571                         tokio::time::sleep(Duration::from_secs(1)).await;
 572                 }
 573         });
 574
 575         // Step 15: Handle LDK Events
 576         let channel_manager_event_listener = channel_manager.clone();
 577         let keys_manager_listener = keys_manager.clone();
 578         // TODO: persist payment info to disk
 579         let inbound_payments: PaymentInfoStorage = Arc::new(Mutex::new(HashMap::new()));
 580         let outbound_payments: PaymentInfoStorage = Arc::new(Mutex::new(HashMap::new()));
 581         let inbound_pmts_for_events = inbound_payments.clone();
 582         let outbound_pmts_for_events = outbound_payments.clone();
 583         let network = args.network;
 584         let bitcoind_rpc = bitcoind_client.clone();
 585         let handle = tokio::runtime::Handle::current();
 586         let event_handler = move |event: &Event| {
 587                 handle.block_on(handle_ldk_events(
 588                         channel_manager_event_listener.clone(),
 589                         bitcoind_rpc.clone(),
 590                         keys_manager_listener.clone(),
 591                         inbound_pmts_for_events.clone(),
 592                         outbound_pmts_for_events.clone(),
 593                         network,
 594                         event,
 595                 ));
 596         };
 597
 598         // Step 16: Initialize routing ProbabilisticScorer
 599         let scorer_path = format!("{}/prob_scorer", ldk_data_dir.clone());
 600         let scorer = Arc::new(Mutex::new(disk::read_scorer(
 601                 Path::new(&scorer_path),
 602                 Arc::clone(&network_graph),
 603         )));
 604         let scorer_persist = Arc::clone(&scorer);
 605         tokio::spawn(async move {
 606                 let mut interval = tokio::time::interval(Duration::from_secs(600));
 607                 loop {
 608                         interval.tick().await;
 609                         if disk::persist_scorer(Path::new(&scorer_path), &scorer_persist.lock().unwrap())
 610                                 .is_err()
 611                         {
 612                                 // Persistence errors here are non-fatal as channels will be re-scored as payments
 613                                 // fail, but they may indicate a disk error which could be fatal elsewhere.
 614                                 eprintln!("Warning: Failed to persist scorer, check your disk and permissions");
 615                         }
 616                 }
 617         });
 618
 619         // Step 17: Create InvoicePayer
 620         let router = DefaultRouter::new(network_graph.clone(), logger.clone());
 621         let invoice_payer = Arc::new(InvoicePayer::new(
 622                 channel_manager.clone(),
 623                 router,
 624                 scorer.clone(),
 625                 logger.clone(),
 626                 event_handler,
 627                 payment::RetryAttempts(5),
 628         ));
 629
 630         // Step 18: Persist ChannelManager
 631         let data_dir = ldk_data_dir.clone();
 632         let persist_channel_manager_callback =
 633                 move |node: &ChannelManager| FilesystemPersister::persist_manager(data_dir.clone(), &*node);
 634
 635         // Step 19: Background Processing
 636         let background_processor = BackgroundProcessor::start(
 637                 persist_channel_manager_callback,
 638                 invoice_payer.clone(),
 639                 chain_monitor.clone(),
 640                 channel_manager.clone(),
 641                 Some(network_gossip.clone()),
 642                 peer_manager.clone(),
 643                 logger.clone(),
 644         );
 645
 646         // Regularly reconnect to channel peers.
 647         let connect_cm = Arc::clone(&channel_manager);
 648         let connect_pm = Arc::clone(&peer_manager);
 649         let peer_data_path = format!("{}/channel_peer_data", ldk_data_dir.clone());
 650         tokio::spawn(async move {
 651                 let mut interval = tokio::time::interval(Duration::from_secs(1));
 652                 loop {
 653                         interval.tick().await;
 654                         match disk::read_channel_peer_data(Path::new(&peer_data_path)) {
 655                                 Ok(info) => {
 656                                         let peers = connect_pm.get_peer_node_ids();
 657                                         for node_id in connect_cm
 658                                                 .list_channels()
 659                                                 .iter()
 660                                                 .map(|chan| chan.counterparty.node_id)
 661                                                 .filter(|id| !peers.contains(id))
 662                                         {
 663                                                 for (pubkey, peer_addr) in info.iter() {
 664                                                         if *pubkey == node_id {
 665                                                                 let _ = cli::do_connect_peer(
 666                                                                         *pubkey,
 667                                                                         peer_addr.clone(),
 668                                                                         Arc::clone(&connect_pm),
 669                                                                 )
 670                                                                 .await;
 671                                                         }
 672                                                 }
 673                                         }
 674                                 }
 675                                 Err(e) => println!("ERROR: errored reading channel peer info from disk: {:?}", e),
 676                         }
 677                 }
 678         });
 679
 680         // Regularly broadcast our node_announcement. This is only required (or possible) if we have
 681         // some public channels, and is only useful if we have public listen address(es) to announce.
 682         // In a production environment, this should occur only after the announcement of new channels
 683         // to avoid churn in the global network graph.
 684         let chan_manager = Arc::clone(&channel_manager);
 685         let network = args.network;
 686         if !args.ldk_announced_listen_addr.is_empty() {
 687                 tokio::spawn(async move {
 688                         let mut interval = tokio::time::interval(Duration::from_secs(60));
 689                         loop {
 690                                 interval.tick().await;
 691                                 chan_manager.broadcast_node_announcement(
 692                                         [0; 3],
 693                                         args.ldk_announced_node_name,
 694                                         args.ldk_announced_listen_addr.clone(),
 695                                 );
 696                         }
 697                 });
 698         }
 699
 700         // Start the CLI.
 701         cli::poll_for_user_input(
 702                 Arc::clone(&invoice_payer),
 703                 Arc::clone(&peer_manager),
 704                 Arc::clone(&channel_manager),
 705                 Arc::clone(&keys_manager),
 706                 Arc::clone(&network_graph),
 707                 inbound_payments,
 708                 outbound_payments,
 709                 ldk_data_dir.clone(),
 710                 network,
 711         )
 712         .await;
 713
 714         // Disconnect our peers and stop accepting new connections. This ensures we don't continue
 715         // updating our channel data after we've stopped the background processor.
 716         stop_listen.store(true, Ordering::Release);
 717         peer_manager.disconnect_all_peers();
 718
 719         // Stop the background processor.
 720         background_processor.stop().unwrap();
 721 }
 722
 723 #[tokio::main]
 724 pub async fn main() {
 725         start_ldk().await;
 726 }