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