a974b7684c14a67348cfe946fb54b644f650d565
[ldk-sample] / 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::Scorer;
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::{Arc, Mutex};
52 use std::time::{Duration, SystemTime};
53
54 pub(crate) enum HTLCStatus {
55         Pending,
56         Succeeded,
57         Failed,
58 }
59
60 pub(crate) struct MillisatAmount(Option<u64>);
61
62 impl fmt::Display for MillisatAmount {
63         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
64                 match self.0 {
65                         Some(amt) => write!(f, "{}", amt),
66                         None => write!(f, "unknown"),
67                 }
68         }
69 }
70
71 pub(crate) struct PaymentInfo {
72         preimage: Option<PaymentPreimage>,
73         secret: Option<PaymentSecret>,
74         status: HTLCStatus,
75         amt_msat: MillisatAmount,
76 }
77
78 pub(crate) type PaymentInfoStorage = Arc<Mutex<HashMap<PaymentHash, PaymentInfo>>>;
79
80 type ChainMonitor = chainmonitor::ChainMonitor<
81         InMemorySigner,
82         Arc<dyn Filter + Send + Sync>,
83         Arc<BitcoindClient>,
84         Arc<BitcoindClient>,
85         Arc<FilesystemLogger>,
86         Arc<FilesystemPersister>,
87 >;
88
89 pub(crate) type PeerManager = SimpleArcPeerManager<
90         SocketDescriptor,
91         ChainMonitor,
92         BitcoindClient,
93         BitcoindClient,
94         dyn chain::Access + Send + Sync,
95         FilesystemLogger,
96 >;
97
98 pub(crate) type ChannelManager =
99         SimpleArcChannelManager<ChainMonitor, BitcoindClient, BitcoindClient, FilesystemLogger>;
100
101 pub(crate) type InvoicePayer<E> = payment::InvoicePayer<
102         Arc<ChannelManager>,
103         Router,
104         Arc<Mutex<Scorer>>,
105         Arc<FilesystemLogger>,
106         E,
107 >;
108
109 type Router = DefaultRouter<Arc<NetworkGraph>, Arc<FilesystemLogger>>;
110
111 async fn handle_ldk_events(
112         channel_manager: Arc<ChannelManager>, bitcoind_client: Arc<BitcoindClient>,
113         keys_manager: Arc<KeysManager>, inbound_payments: PaymentInfoStorage,
114         outbound_payments: PaymentInfoStorage, network: Network, event: &Event,
115 ) {
116         match event {
117                 Event::FundingGenerationReady {
118                         temporary_channel_id,
119                         channel_value_satoshis,
120                         output_script,
121                         ..
122                 } => {
123                         // Construct the raw transaction with one output, that is paid the amount of the
124                         // channel.
125                         let addr = WitnessProgram::from_scriptpubkey(
126                                 &output_script[..],
127                                 match network {
128                                         Network::Bitcoin => bitcoin_bech32::constants::Network::Bitcoin,
129                                         Network::Testnet => bitcoin_bech32::constants::Network::Testnet,
130                                         Network::Regtest => bitcoin_bech32::constants::Network::Regtest,
131                                         Network::Signet => bitcoin_bech32::constants::Network::Signet,
132                                 },
133                         )
134                         .expect("Lightning funding tx should always be to a SegWit output")
135                         .to_address();
136                         let mut outputs = vec![HashMap::with_capacity(1)];
137                         outputs[0].insert(addr, *channel_value_satoshis as f64 / 100_000_000.0);
138                         let raw_tx = bitcoind_client.create_raw_transaction(outputs).await;
139
140                         // Have your wallet put the inputs into the transaction such that the output is
141                         // satisfied.
142                         let funded_tx = bitcoind_client.fund_raw_transaction(raw_tx).await;
143
144                         // Sign the final funding transaction and broadcast it.
145                         let signed_tx = bitcoind_client.sign_raw_transaction_with_wallet(funded_tx.hex).await;
146                         assert_eq!(signed_tx.complete, true);
147                         let final_tx: Transaction =
148                                 encode::deserialize(&hex_utils::to_vec(&signed_tx.hex).unwrap()).unwrap();
149                         // Give the funding transaction back to LDK for opening the channel.
150                         if channel_manager
151                                 .funding_transaction_generated(&temporary_channel_id, final_tx)
152                                 .is_err()
153                         {
154                                 println!(
155                                         "\nERROR: Channel went away before we could fund it. The peer disconnected or refused the channel.");
156                                 print!("> ");
157                                 io::stdout().flush().unwrap();
158                         }
159                 }
160                 Event::PaymentReceived { payment_hash, purpose, amt, .. } => {
161                         let mut payments = inbound_payments.lock().unwrap();
162                         let (payment_preimage, payment_secret) = match purpose {
163                                 PaymentPurpose::InvoicePayment { payment_preimage, payment_secret, .. } => {
164                                         (*payment_preimage, Some(*payment_secret))
165                                 }
166                                 PaymentPurpose::SpontaneousPayment(preimage) => (Some(*preimage), None),
167                         };
168                         let status = match channel_manager.claim_funds(payment_preimage.unwrap()) {
169                                 true => {
170                                         println!(
171                                                 "\nEVENT: received payment from payment hash {} of {} millisatoshis",
172                                                 hex_utils::hex_str(&payment_hash.0),
173                                                 amt
174                                         );
175                                         print!("> ");
176                                         io::stdout().flush().unwrap();
177                                         HTLCStatus::Succeeded
178                                 }
179                                 _ => HTLCStatus::Failed,
180                         };
181                         match payments.entry(*payment_hash) {
182                                 Entry::Occupied(mut e) => {
183                                         let payment = e.get_mut();
184                                         payment.status = status;
185                                         payment.preimage = payment_preimage;
186                                         payment.secret = payment_secret;
187                                 }
188                                 Entry::Vacant(e) => {
189                                         e.insert(PaymentInfo {
190                                                 preimage: payment_preimage,
191                                                 secret: payment_secret,
192                                                 status,
193                                                 amt_msat: MillisatAmount(Some(*amt)),
194                                         });
195                                 }
196                         }
197                 }
198                 Event::PaymentSent { payment_preimage, payment_hash, fee_paid_msat, .. } => {
199                         let mut payments = outbound_payments.lock().unwrap();
200                         for (hash, payment) in payments.iter_mut() {
201                                 if *hash == *payment_hash {
202                                         payment.preimage = Some(*payment_preimage);
203                                         payment.status = HTLCStatus::Succeeded;
204                                         println!(
205                                                 "\nEVENT: successfully sent payment of {} millisatoshis{} from \
206                                                                  payment hash {:?} with preimage {:?}",
207                                                 payment.amt_msat,
208                                                 if let Some(fee) = fee_paid_msat {
209                                                         format!(" (fee {} msat)", fee)
210                                                 } else {
211                                                         "".to_string()
212                                                 },
213                                                 hex_utils::hex_str(&payment_hash.0),
214                                                 hex_utils::hex_str(&payment_preimage.0)
215                                         );
216                                         print!("> ");
217                                         io::stdout().flush().unwrap();
218                                 }
219                         }
220                 }
221                 Event::OpenChannelRequest { .. } => {
222                         // Unreachable, we don't set manually_accept_inbound_channels
223                 }
224                 Event::PaymentPathSuccessful { .. } => {}
225                 Event::PaymentPathFailed { .. } => {}
226                 Event::PaymentFailed { payment_hash, .. } => {
227                         print!(
228                                 "\nEVENT: Failed to send payment to payment hash {:?}: exhausted payment retry attempts",
229                                 hex_utils::hex_str(&payment_hash.0)
230                         );
231                         print!("> ");
232                         io::stdout().flush().unwrap();
233
234                         let mut payments = outbound_payments.lock().unwrap();
235                         if payments.contains_key(&payment_hash) {
236                                 let payment = payments.get_mut(&payment_hash).unwrap();
237                                 payment.status = HTLCStatus::Failed;
238                         }
239                 }
240                 Event::PaymentForwarded { fee_earned_msat, claim_from_onchain_tx } => {
241                         let from_onchain_str = if *claim_from_onchain_tx {
242                                 "from onchain downstream claim"
243                         } else {
244                                 "from HTLC fulfill message"
245                         };
246                         if let Some(fee_earned) = fee_earned_msat {
247                                 println!(
248                                         "\nEVENT: Forwarded payment, earning {} msat {}",
249                                         fee_earned, from_onchain_str
250                                 );
251                         } else {
252                                 println!("\nEVENT: Forwarded payment, claiming onchain {}", from_onchain_str);
253                         }
254                         print!("> ");
255                         io::stdout().flush().unwrap();
256                 }
257                 Event::PendingHTLCsForwardable { time_forwardable } => {
258                         let forwarding_channel_manager = channel_manager.clone();
259                         let min = time_forwardable.as_millis() as u64;
260                         tokio::spawn(async move {
261                                 let millis_to_sleep = thread_rng().gen_range(min, min * 5) as u64;
262                                 tokio::time::sleep(Duration::from_millis(millis_to_sleep)).await;
263                                 forwarding_channel_manager.process_pending_htlc_forwards();
264                         });
265                 }
266                 Event::SpendableOutputs { outputs } => {
267                         let destination_address = bitcoind_client.get_new_address().await;
268                         let output_descriptors = &outputs.iter().map(|a| a).collect::<Vec<_>>();
269                         let tx_feerate =
270                                 bitcoind_client.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
271                         let spending_tx = keys_manager
272                                 .spend_spendable_outputs(
273                                         output_descriptors,
274                                         Vec::new(),
275                                         destination_address.script_pubkey(),
276                                         tx_feerate,
277                                         &Secp256k1::new(),
278                                 )
279                                 .unwrap();
280                         bitcoind_client.broadcast_transaction(&spending_tx);
281                 }
282                 Event::ChannelClosed { channel_id, reason, user_channel_id: _ } => {
283                         println!(
284                                 "\nEVENT: Channel {} closed due to: {:?}",
285                                 hex_utils::hex_str(channel_id),
286                                 reason
287                         );
288                         print!("> ");
289                         io::stdout().flush().unwrap();
290                 }
291                 Event::DiscardFunding { .. } => {
292                         // A "real" node should probably "lock" the UTXOs spent in funding transactions until
293                         // the funding transaction either confirms, or this event is generated.
294                 }
295         }
296 }
297
298 async fn start_ldk() {
299         let args = match cli::parse_startup_args() {
300                 Ok(user_args) => user_args,
301                 Err(()) => return,
302         };
303
304         // Initialize the LDK data directory if necessary.
305         let ldk_data_dir = format!("{}/.ldk", args.ldk_storage_dir_path);
306         fs::create_dir_all(ldk_data_dir.clone()).unwrap();
307
308         // Initialize our bitcoind client.
309         let bitcoind_client = match BitcoindClient::new(
310                 args.bitcoind_rpc_host.clone(),
311                 args.bitcoind_rpc_port,
312                 args.bitcoind_rpc_username.clone(),
313                 args.bitcoind_rpc_password.clone(),
314                 tokio::runtime::Handle::current(),
315         )
316         .await
317         {
318                 Ok(client) => Arc::new(client),
319                 Err(e) => {
320                         println!("Failed to connect to bitcoind client: {}", e);
321                         return;
322                 }
323         };
324
325         // Check that the bitcoind we've connected to is running the network we expect
326         let bitcoind_chain = bitcoind_client.get_blockchain_info().await.chain;
327         if bitcoind_chain
328                 != match args.network {
329                         bitcoin::Network::Bitcoin => "main",
330                         bitcoin::Network::Testnet => "test",
331                         bitcoin::Network::Regtest => "regtest",
332                         bitcoin::Network::Signet => "signet",
333                 } {
334                 println!(
335                         "Chain argument ({}) didn't match bitcoind chain ({})",
336                         args.network, bitcoind_chain
337                 );
338                 return;
339         }
340
341         // ## Setup
342         // Step 1: Initialize the FeeEstimator
343
344         // BitcoindClient implements the FeeEstimator trait, so it'll act as our fee estimator.
345         let fee_estimator = bitcoind_client.clone();
346
347         // Step 2: Initialize the Logger
348         let logger = Arc::new(FilesystemLogger::new(ldk_data_dir.clone()));
349
350         // Step 3: Initialize the BroadcasterInterface
351
352         // BitcoindClient implements the BroadcasterInterface trait, so it'll act as our transaction
353         // broadcaster.
354         let broadcaster = bitcoind_client.clone();
355
356         // Step 4: Initialize Persist
357         let persister = Arc::new(FilesystemPersister::new(ldk_data_dir.clone()));
358
359         // Step 5: Initialize the ChainMonitor
360         let chain_monitor: Arc<ChainMonitor> = Arc::new(chainmonitor::ChainMonitor::new(
361                 None,
362                 broadcaster.clone(),
363                 logger.clone(),
364                 fee_estimator.clone(),
365                 persister.clone(),
366         ));
367
368         // Step 6: Initialize the KeysManager
369
370         // The key seed that we use to derive the node privkey (that corresponds to the node pubkey) and
371         // other secret key material.
372         let keys_seed_path = format!("{}/keys_seed", ldk_data_dir.clone());
373         let keys_seed = if let Ok(seed) = fs::read(keys_seed_path.clone()) {
374                 assert_eq!(seed.len(), 32);
375                 let mut key = [0; 32];
376                 key.copy_from_slice(&seed);
377                 key
378         } else {
379                 let mut key = [0; 32];
380                 thread_rng().fill_bytes(&mut key);
381                 match File::create(keys_seed_path.clone()) {
382                         Ok(mut f) => {
383                                 f.write_all(&key).expect("Failed to write node keys seed to disk");
384                                 f.sync_all().expect("Failed to sync node keys seed to disk");
385                         }
386                         Err(e) => {
387                                 println!("ERROR: Unable to create keys seed file {}: {}", keys_seed_path, e);
388                                 return;
389                         }
390                 }
391                 key
392         };
393         let cur = SystemTime::now().duration_since(SystemTime::UNIX_EPOCH).unwrap();
394         let keys_manager = Arc::new(KeysManager::new(&keys_seed, cur.as_secs(), cur.subsec_nanos()));
395
396         // Step 7: Read ChannelMonitor state from disk
397         let mut channelmonitors = persister.read_channelmonitors(keys_manager.clone()).unwrap();
398
399         // Step 8: Initialize the ChannelManager
400         let mut user_config = UserConfig::default();
401         user_config.peer_channel_config_limits.force_announced_channel_preference = false;
402         let mut restarting_node = true;
403         let (channel_manager_blockhash, channel_manager) = {
404                 if let Ok(mut f) = fs::File::open(format!("{}/manager", ldk_data_dir.clone())) {
405                         let mut channel_monitor_mut_references = Vec::new();
406                         for (_, channel_monitor) in channelmonitors.iter_mut() {
407                                 channel_monitor_mut_references.push(channel_monitor);
408                         }
409                         let read_args = ChannelManagerReadArgs::new(
410                                 keys_manager.clone(),
411                                 fee_estimator.clone(),
412                                 chain_monitor.clone(),
413                                 broadcaster.clone(),
414                                 logger.clone(),
415                                 user_config,
416                                 channel_monitor_mut_references,
417                         );
418                         <(BlockHash, ChannelManager)>::read(&mut f, read_args).unwrap()
419                 } else {
420                         // We're starting a fresh node.
421                         restarting_node = false;
422                         let getinfo_resp = bitcoind_client.get_blockchain_info().await;
423
424                         let chain_params = ChainParameters {
425                                 network: args.network,
426                                 best_block: BestBlock::new(
427                                         getinfo_resp.latest_blockhash,
428                                         getinfo_resp.latest_height as u32,
429                                 ),
430                         };
431                         let fresh_channel_manager = channelmanager::ChannelManager::new(
432                                 fee_estimator.clone(),
433                                 chain_monitor.clone(),
434                                 broadcaster.clone(),
435                                 logger.clone(),
436                                 keys_manager.clone(),
437                                 user_config,
438                                 chain_params,
439                         );
440                         (getinfo_resp.latest_blockhash, fresh_channel_manager)
441                 }
442         };
443
444         // Step 9: Sync ChannelMonitors and ChannelManager to chain tip
445         let mut chain_listener_channel_monitors = Vec::new();
446         let mut cache = UnboundedCache::new();
447         let mut chain_tip: Option<poll::ValidatedBlockHeader> = None;
448         if restarting_node {
449                 let mut chain_listeners =
450                         vec![(channel_manager_blockhash, &channel_manager as &dyn chain::Listen)];
451
452                 for (blockhash, channel_monitor) in channelmonitors.drain(..) {
453                         let outpoint = channel_monitor.get_funding_txo().0;
454                         chain_listener_channel_monitors.push((
455                                 blockhash,
456                                 (channel_monitor, broadcaster.clone(), fee_estimator.clone(), logger.clone()),
457                                 outpoint,
458                         ));
459                 }
460
461                 for monitor_listener_info in chain_listener_channel_monitors.iter_mut() {
462                         chain_listeners
463                                 .push((monitor_listener_info.0, &monitor_listener_info.1 as &dyn chain::Listen));
464                 }
465                 chain_tip = Some(
466                         init::synchronize_listeners(
467                                 &mut bitcoind_client.deref(),
468                                 args.network,
469                                 &mut cache,
470                                 chain_listeners,
471                         )
472                         .await
473                         .unwrap(),
474                 );
475         }
476
477         // Step 10: Give ChannelMonitors to ChainMonitor
478         for item in chain_listener_channel_monitors.drain(..) {
479                 let channel_monitor = item.1 .0;
480                 let funding_outpoint = item.2;
481                 chain_monitor.watch_channel(funding_outpoint, channel_monitor).unwrap();
482         }
483
484         // Step 11: Optional: Initialize the NetGraphMsgHandler
485         let genesis = genesis_block(args.network).header.block_hash();
486         let network_graph_path = format!("{}/network_graph", ldk_data_dir.clone());
487         let network_graph = Arc::new(disk::read_network(Path::new(&network_graph_path), genesis));
488         let network_gossip = Arc::new(NetGraphMsgHandler::new(
489                 Arc::clone(&network_graph),
490                 None::<Arc<dyn chain::Access + Send + Sync>>,
491                 logger.clone(),
492         ));
493         let network_graph_persist = Arc::clone(&network_graph);
494         tokio::spawn(async move {
495                 let mut interval = tokio::time::interval(Duration::from_secs(600));
496                 loop {
497                         interval.tick().await;
498                         if disk::persist_network(Path::new(&network_graph_path), &network_graph_persist)
499                                 .is_err()
500                         {
501                                 // Persistence errors here are non-fatal as we can just fetch the routing graph
502                                 // again later, but they may indicate a disk error which could be fatal elsewhere.
503                                 eprintln!(
504                                         "Warning: Failed to persist network graph, check your disk and permissions"
505                                 );
506                         }
507                 }
508         });
509
510         // Step 12: Initialize the PeerManager
511         let channel_manager: Arc<ChannelManager> = Arc::new(channel_manager);
512         let mut ephemeral_bytes = [0; 32];
513         rand::thread_rng().fill_bytes(&mut ephemeral_bytes);
514         let lightning_msg_handler = MessageHandler {
515                 chan_handler: channel_manager.clone(),
516                 route_handler: network_gossip.clone(),
517         };
518         let peer_manager: Arc<PeerManager> = Arc::new(PeerManager::new(
519                 lightning_msg_handler,
520                 keys_manager.get_node_secret(Recipient::Node).unwrap(),
521                 &ephemeral_bytes,
522                 logger.clone(),
523                 Arc::new(IgnoringMessageHandler {}),
524         ));
525
526         // ## Running LDK
527         // Step 13: Initialize networking
528
529         let peer_manager_connection_handler = peer_manager.clone();
530         let listening_port = args.ldk_peer_listening_port;
531         tokio::spawn(async move {
532                 let listener = tokio::net::TcpListener::bind(format!("0.0.0.0:{}", listening_port))
533                         .await
534                         .expect("Failed to bind to listen port - is something else already listening on it?");
535                 loop {
536                         let peer_mgr = peer_manager_connection_handler.clone();
537                         let tcp_stream = listener.accept().await.unwrap().0;
538                         tokio::spawn(async move {
539                                 lightning_net_tokio::setup_inbound(
540                                         peer_mgr.clone(),
541                                         tcp_stream.into_std().unwrap(),
542                                 )
543                                 .await;
544                         });
545                 }
546         });
547
548         // Step 14: Connect and Disconnect Blocks
549         if chain_tip.is_none() {
550                 chain_tip =
551                         Some(init::validate_best_block_header(&mut bitcoind_client.deref()).await.unwrap());
552         }
553         let channel_manager_listener = channel_manager.clone();
554         let chain_monitor_listener = chain_monitor.clone();
555         let bitcoind_block_source = bitcoind_client.clone();
556         let network = args.network;
557         tokio::spawn(async move {
558                 let mut derefed = bitcoind_block_source.deref();
559                 let chain_poller = poll::ChainPoller::new(&mut derefed, network);
560                 let chain_listener = (chain_monitor_listener, channel_manager_listener);
561                 let mut spv_client =
562                         SpvClient::new(chain_tip.unwrap(), chain_poller, &mut cache, &chain_listener);
563                 loop {
564                         spv_client.poll_best_tip().await.unwrap();
565                         tokio::time::sleep(Duration::from_secs(1)).await;
566                 }
567         });
568
569         // Step 15: Handle LDK Events
570         let channel_manager_event_listener = channel_manager.clone();
571         let keys_manager_listener = keys_manager.clone();
572         // TODO: persist payment info to disk
573         let inbound_payments: PaymentInfoStorage = Arc::new(Mutex::new(HashMap::new()));
574         let outbound_payments: PaymentInfoStorage = Arc::new(Mutex::new(HashMap::new()));
575         let inbound_pmts_for_events = inbound_payments.clone();
576         let outbound_pmts_for_events = outbound_payments.clone();
577         let network = args.network;
578         let bitcoind_rpc = bitcoind_client.clone();
579         let handle = tokio::runtime::Handle::current();
580         let event_handler = move |event: &Event| {
581                 handle.block_on(handle_ldk_events(
582                         channel_manager_event_listener.clone(),
583                         bitcoind_rpc.clone(),
584                         keys_manager_listener.clone(),
585                         inbound_pmts_for_events.clone(),
586                         outbound_pmts_for_events.clone(),
587                         network,
588                         event,
589                 ));
590         };
591
592         // Step 16: Initialize routing Scorer
593         let scorer_path = format!("{}/scorer", ldk_data_dir.clone());
594         let scorer = Arc::new(Mutex::new(disk::read_scorer(Path::new(&scorer_path))));
595         let scorer_persist = Arc::clone(&scorer);
596         tokio::spawn(async move {
597                 let mut interval = tokio::time::interval(Duration::from_secs(600));
598                 loop {
599                         interval.tick().await;
600                         if disk::persist_scorer(Path::new(&scorer_path), &scorer_persist.lock().unwrap())
601                                 .is_err()
602                         {
603                                 // Persistence errors here are non-fatal as channels will be re-scored as payments
604                                 // fail, but they may indicate a disk error which could be fatal elsewhere.
605                                 eprintln!("Warning: Failed to persist scorer, check your disk and permissions");
606                         }
607                 }
608         });
609
610         // Step 17: Create InvoicePayer
611         let router = DefaultRouter::new(network_graph.clone(), logger.clone());
612         let invoice_payer = Arc::new(InvoicePayer::new(
613                 channel_manager.clone(),
614                 router,
615                 scorer.clone(),
616                 logger.clone(),
617                 event_handler,
618                 payment::RetryAttempts(5),
619         ));
620
621         // Step 18: Persist ChannelManager
622         let data_dir = ldk_data_dir.clone();
623         let persist_channel_manager_callback =
624                 move |node: &ChannelManager| FilesystemPersister::persist_manager(data_dir.clone(), &*node);
625
626         // Step 19: Background Processing
627         let background_processor = BackgroundProcessor::start(
628                 persist_channel_manager_callback,
629                 invoice_payer.clone(),
630                 chain_monitor.clone(),
631                 channel_manager.clone(),
632                 Some(network_gossip.clone()),
633                 peer_manager.clone(),
634                 logger.clone(),
635         );
636
637         // Regularly reconnect to channel peers.
638         let connect_cm = Arc::clone(&channel_manager);
639         let connect_pm = Arc::clone(&peer_manager);
640         let peer_data_path = format!("{}/channel_peer_data", ldk_data_dir.clone());
641         tokio::spawn(async move {
642                 let mut interval = tokio::time::interval(Duration::from_secs(1));
643                 loop {
644                         interval.tick().await;
645                         match disk::read_channel_peer_data(Path::new(&peer_data_path)) {
646                                 Ok(info) => {
647                                         let peers = connect_pm.get_peer_node_ids();
648                                         for node_id in connect_cm
649                                                 .list_channels()
650                                                 .iter()
651                                                 .map(|chan| chan.counterparty.node_id)
652                                                 .filter(|id| !peers.contains(id))
653                                         {
654                                                 for (pubkey, peer_addr) in info.iter() {
655                                                         if *pubkey == node_id {
656                                                                 let _ = cli::do_connect_peer(
657                                                                         *pubkey,
658                                                                         peer_addr.clone(),
659                                                                         Arc::clone(&connect_pm),
660                                                                 )
661                                                                 .await;
662                                                         }
663                                                 }
664                                         }
665                                 }
666                                 Err(e) => println!("ERROR: errored reading channel peer info from disk: {:?}", e),
667                         }
668                 }
669         });
670
671         // Regularly broadcast our node_announcement. This is only required (or possible) if we have
672         // some public channels, and is only useful if we have public listen address(es) to announce.
673         // In a production environment, this should occur only after the announcement of new channels
674         // to avoid churn in the global network graph.
675         let chan_manager = Arc::clone(&channel_manager);
676         let network = args.network;
677         if !args.ldk_announced_listen_addr.is_empty() {
678                 tokio::spawn(async move {
679                         let mut interval = tokio::time::interval(Duration::from_secs(60));
680                         loop {
681                                 interval.tick().await;
682                                 chan_manager.broadcast_node_announcement(
683                                         [0; 3],
684                                         args.ldk_announced_node_name,
685                                         args.ldk_announced_listen_addr.clone(),
686                                 );
687                         }
688                 });
689         }
690
691         // Start the CLI.
692         cli::poll_for_user_input(
693                 invoice_payer.clone(),
694                 peer_manager.clone(),
695                 channel_manager.clone(),
696                 keys_manager.clone(),
697                 inbound_payments,
698                 outbound_payments,
699                 ldk_data_dir.clone(),
700                 network,
701         )
702         .await;
703
704         // Stop the background processor.
705         background_processor.stop().unwrap();
706 }
707
708 #[tokio::main]
709 pub async fn main() {
710         start_ldk().await;
711 }