1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! A module for paying Lightning invoices.
12 //! Defines an [`InvoicePayer`] utility for paying invoices, parameterized by [`Payer`] and
13 //! [`Router`] traits. Implementations of [`Payer`] provide the payer's node id, channels, and means
14 //! to send a payment over a [`Route`]. Implementations of [`Router`] find a [`Route`] between payer
15 //! and payee using information provided by the payer and from the payee's [`Invoice`].
17 //! [`InvoicePayer`] is capable of retrying failed payments. It accomplishes this by implementing
18 //! [`EventHandler`] which decorates a user-provided handler. It will intercept any
19 //! [`Event::PaymentPathFailed`] events and retry the failed paths for a fixed number of total
20 //! attempts or until retry is no longer possible. In such a situation, [`InvoicePayer`] will pass
21 //! along the events to the user-provided handler.
26 //! # extern crate lightning;
27 //! # extern crate lightning_invoice;
28 //! # extern crate secp256k1;
30 //! # use lightning::ln::{PaymentHash, PaymentSecret};
31 //! # use lightning::ln::channelmanager::{ChannelDetails, PaymentId, PaymentSendFailure};
32 //! # use lightning::ln::msgs::LightningError;
33 //! # use lightning::routing::router::{Route, RouteParameters};
34 //! # use lightning::util::events::{Event, EventHandler, EventsProvider};
35 //! # use lightning::util::logger::{Logger, Record};
36 //! # use lightning_invoice::Invoice;
37 //! # use lightning_invoice::payment::{InvoicePayer, Payer, RetryAttempts, Router};
38 //! # use secp256k1::key::PublicKey;
39 //! # use std::ops::Deref;
41 //! # struct FakeEventProvider {}
42 //! # impl EventsProvider for FakeEventProvider {
43 //! # fn process_pending_events<H: Deref>(&self, handler: H) where H::Target: EventHandler {}
46 //! # struct FakePayer {}
47 //! # impl Payer for FakePayer {
48 //! # fn node_id(&self) -> PublicKey { unimplemented!() }
49 //! # fn first_hops(&self) -> Vec<ChannelDetails> { unimplemented!() }
50 //! # fn send_payment(
51 //! # &self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>
52 //! # ) -> Result<PaymentId, PaymentSendFailure> { unimplemented!() }
53 //! # fn retry_payment(
54 //! # &self, route: &Route, payment_id: PaymentId
55 //! # ) -> Result<(), PaymentSendFailure> { unimplemented!() }
58 //! # struct FakeRouter {};
59 //! # impl Router for FakeRouter {
61 //! # &self, payer: &PublicKey, params: &RouteParameters,
62 //! # first_hops: Option<&[&ChannelDetails]>
63 //! # ) -> Result<Route, LightningError> { unimplemented!() }
66 //! # struct FakeLogger {};
67 //! # impl Logger for FakeLogger {
68 //! # fn log(&self, record: &Record) { unimplemented!() }
72 //! let event_handler = |event: &Event| {
74 //! Event::PaymentPathFailed { .. } => println!("payment failed after retries"),
75 //! Event::PaymentSent { .. } => println!("payment successful"),
79 //! # let payer = FakePayer {};
80 //! # let router = FakeRouter {};
81 //! # let logger = FakeLogger {};
82 //! let invoice_payer = InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2));
84 //! let invoice = "...";
85 //! let invoice = invoice.parse::<Invoice>().unwrap();
86 //! invoice_payer.pay_invoice(&invoice).unwrap();
88 //! # let event_provider = FakeEventProvider {};
90 //! event_provider.process_pending_events(&invoice_payer);
97 //! The [`Route`] is computed before each payment attempt. Any updates affecting path finding such
98 //! as updates to the network graph or changes to channel scores should be applied prior to
99 //! retries, typically by way of composing [`EventHandler`]s accordingly.
103 use bitcoin_hashes::Hash;
105 use lightning::ln::{PaymentHash, PaymentSecret};
106 use lightning::ln::channelmanager::{ChannelDetails, PaymentId, PaymentSendFailure};
107 use lightning::ln::msgs::LightningError;
108 use lightning::routing::router::{Payee, Route, RouteParameters};
109 use lightning::util::events::{Event, EventHandler};
110 use lightning::util::logger::Logger;
112 use secp256k1::key::PublicKey;
114 use std::collections::hash_map::{self, HashMap};
116 use std::sync::Mutex;
117 use std::time::{Duration, SystemTime};
119 /// A utility for paying [`Invoice]`s.
120 pub struct InvoicePayer<P: Deref, R, L: Deref, E>
131 payment_cache: Mutex<HashMap<PaymentHash, usize>>,
132 retry_attempts: RetryAttempts,
135 /// A trait defining behavior of an [`Invoice`] payer.
137 /// Returns the payer's node id.
138 fn node_id(&self) -> PublicKey;
140 /// Returns the payer's channels.
141 fn first_hops(&self) -> Vec<ChannelDetails>;
143 /// Sends a payment over the Lightning Network using the given [`Route`].
145 &self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>
146 ) -> Result<PaymentId, PaymentSendFailure>;
148 /// Retries a failed payment path for the [`PaymentId`] using the given [`Route`].
149 fn retry_payment(&self, route: &Route, payment_id: PaymentId) -> Result<(), PaymentSendFailure>;
152 /// A trait defining behavior for routing an [`Invoice`] payment.
154 /// Finds a [`Route`] between `payer` and `payee` for a payment with the given values.
156 &self, payer: &PublicKey, params: &RouteParameters, first_hops: Option<&[&ChannelDetails]>
157 ) -> Result<Route, LightningError>;
160 /// Number of attempts to retry payment path failures for an [`Invoice`].
161 #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
162 pub struct RetryAttempts(pub usize);
164 /// An error that may occur when making a payment.
165 #[derive(Clone, Debug)]
166 pub enum PaymentError {
167 /// An error resulting from the provided [`Invoice`] or payment hash.
168 Invoice(&'static str),
169 /// An error occurring when finding a route.
170 Routing(LightningError),
171 /// An error occurring when sending a payment.
172 Sending(PaymentSendFailure),
175 impl<P: Deref, R, L: Deref, E> InvoicePayer<P, R, L, E>
182 /// Creates an invoice payer that retries failed payment paths.
184 /// Will forward any [`Event::PaymentPathFailed`] events to the decorated `event_handler` once
185 /// `retry_attempts` has been exceeded for a given [`Invoice`].
187 payer: P, router: R, logger: L, event_handler: E, retry_attempts: RetryAttempts
194 payment_cache: Mutex::new(HashMap::new()),
199 /// Pays the given [`Invoice`], caching it for later use in case a retry is needed.
200 pub fn pay_invoice(&self, invoice: &Invoice) -> Result<PaymentId, PaymentError> {
201 if invoice.amount_milli_satoshis().is_none() {
202 Err(PaymentError::Invoice("amount missing"))
204 self.pay_invoice_internal(invoice, None)
208 /// Pays the given zero-value [`Invoice`] using the given amount, caching it for later use in
209 /// case a retry is needed.
210 pub fn pay_zero_value_invoice(
211 &self, invoice: &Invoice, amount_msats: u64
212 ) -> Result<PaymentId, PaymentError> {
213 if invoice.amount_milli_satoshis().is_some() {
214 Err(PaymentError::Invoice("amount unexpected"))
216 self.pay_invoice_internal(invoice, Some(amount_msats))
220 fn pay_invoice_internal(
221 &self, invoice: &Invoice, amount_msats: Option<u64>
222 ) -> Result<PaymentId, PaymentError> {
223 debug_assert!(invoice.amount_milli_satoshis().is_some() ^ amount_msats.is_some());
224 let payment_hash = PaymentHash(invoice.payment_hash().clone().into_inner());
225 let mut payment_cache = self.payment_cache.lock().unwrap();
226 match payment_cache.entry(payment_hash) {
227 hash_map::Entry::Vacant(entry) => {
228 let payer = self.payer.node_id();
229 let mut payee = Payee::new(invoice.recover_payee_pub_key())
230 .with_expiry_time(expiry_time_from_unix_epoch(&invoice).as_secs())
231 .with_route_hints(invoice.route_hints());
232 if let Some(features) = invoice.features() {
233 payee = payee.with_features(features.clone());
235 let params = RouteParameters {
237 final_value_msat: invoice.amount_milli_satoshis().or(amount_msats).unwrap(),
238 final_cltv_expiry_delta: invoice.min_final_cltv_expiry() as u32,
240 let first_hops = self.payer.first_hops();
241 let route = self.router.find_route(
244 Some(&first_hops.iter().collect::<Vec<_>>()),
245 ).map_err(|e| PaymentError::Routing(e))?;
247 let payment_hash = PaymentHash(invoice.payment_hash().clone().into_inner());
248 let payment_secret = Some(invoice.payment_secret().clone());
249 let payment_id = self.payer.send_payment(&route, payment_hash, &payment_secret)
250 .map_err(|e| PaymentError::Sending(e))?;
254 hash_map::Entry::Occupied(_) => Err(PaymentError::Invoice("payment pending")),
259 &self, payment_id: PaymentId, params: &RouteParameters
260 ) -> Result<(), PaymentError> {
261 let payer = self.payer.node_id();
262 let first_hops = self.payer.first_hops();
263 let route = self.router.find_route(
264 &payer, ¶ms, Some(&first_hops.iter().collect::<Vec<_>>())
265 ).map_err(|e| PaymentError::Routing(e))?;
266 self.payer.retry_payment(&route, payment_id).map_err(|e| PaymentError::Sending(e))
269 /// Removes the payment cached by the given payment hash.
271 /// Should be called once a payment has failed or succeeded if not using [`InvoicePayer`] as an
272 /// [`EventHandler`]. Otherwise, calling this method is unnecessary.
273 pub fn remove_cached_payment(&self, payment_hash: &PaymentHash) {
274 self.payment_cache.lock().unwrap().remove(payment_hash);
278 fn expiry_time_from_unix_epoch(invoice: &Invoice) -> Duration {
279 invoice.timestamp().duration_since(SystemTime::UNIX_EPOCH).unwrap() + invoice.expiry_time()
282 fn has_expired(params: &RouteParameters) -> bool {
283 let expiry_time = Duration::from_secs(params.payee.expiry_time.unwrap());
284 Invoice::is_expired_from_epoch(&SystemTime::UNIX_EPOCH, expiry_time)
287 impl<P: Deref, R, L: Deref, E> EventHandler for InvoicePayer<P, R, L, E>
294 fn handle_event(&self, event: &Event) {
296 Event::PaymentPathFailed { payment_id, payment_hash, rejected_by_dest, retry, .. } => {
297 let mut payment_cache = self.payment_cache.lock().unwrap();
299 let entry = payment_cache.entry(*payment_hash);
301 hash_map::Entry::Occupied(_) => break entry,
302 hash_map::Entry::Vacant(entry) => entry.insert(0),
305 if let hash_map::Entry::Occupied(mut entry) = entry {
306 let max_payment_attempts = self.retry_attempts.0 + 1;
307 let attempts = entry.get_mut();
310 if *rejected_by_dest {
311 log_trace!(self.logger, "Payment {} rejected by destination; not retrying (attempts: {})", log_bytes!(payment_hash.0), attempts);
312 } else if payment_id.is_none() {
313 log_trace!(self.logger, "Payment {} has no id; not retrying (attempts: {})", log_bytes!(payment_hash.0), attempts);
314 } else if *attempts >= max_payment_attempts {
315 log_trace!(self.logger, "Payment {} exceeded maximum attempts; not retrying (attempts: {})", log_bytes!(payment_hash.0), attempts);
316 } else if retry.is_none() {
317 log_trace!(self.logger, "Payment {} missing retry params; not retrying (attempts: {})", log_bytes!(payment_hash.0), attempts);
318 } else if has_expired(retry.as_ref().unwrap()) {
319 log_trace!(self.logger, "Invoice expired for payment {}; not retrying (attempts: {})", log_bytes!(payment_hash.0), attempts);
320 } else if self.retry_payment(*payment_id.as_ref().unwrap(), retry.as_ref().unwrap()).is_err() {
321 log_trace!(self.logger, "Error retrying payment {}; not retrying (attempts: {})", log_bytes!(payment_hash.0), attempts);
323 log_trace!(self.logger, "Payment {} failed; retrying (attempts: {})", log_bytes!(payment_hash.0), attempts);
327 // Either the payment was rejected, the maximum attempts were exceeded, or an
328 // error occurred when attempting to retry.
334 Event::PaymentSent { payment_hash, .. } => {
335 let mut payment_cache = self.payment_cache.lock().unwrap();
336 let attempts = payment_cache
337 .remove(payment_hash)
338 .map_or(1, |attempts| attempts + 1);
339 log_trace!(self.logger, "Payment {} succeeded (attempts: {})", log_bytes!(payment_hash.0), attempts);
344 // Delegate to the decorated event handler unless the payment is retried.
345 self.event_handler.handle_event(event)
352 use crate::{DEFAULT_EXPIRY_TIME, InvoiceBuilder, Currency};
353 use bitcoin_hashes::sha256::Hash as Sha256;
354 use lightning::ln::PaymentPreimage;
355 use lightning::ln::features::{ChannelFeatures, NodeFeatures};
356 use lightning::ln::msgs::{ErrorAction, LightningError};
357 use lightning::routing::router::{Route, RouteHop};
358 use lightning::util::test_utils::TestLogger;
359 use lightning::util::errors::APIError;
360 use lightning::util::events::Event;
361 use secp256k1::{SecretKey, PublicKey, Secp256k1};
362 use std::time::{SystemTime, Duration};
364 fn invoice(payment_preimage: PaymentPreimage) -> Invoice {
365 let payment_hash = Sha256::hash(&payment_preimage.0);
366 let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
367 InvoiceBuilder::new(Currency::Bitcoin)
368 .description("test".into())
369 .payment_hash(payment_hash)
370 .payment_secret(PaymentSecret([0; 32]))
372 .min_final_cltv_expiry(144)
373 .amount_milli_satoshis(128)
374 .build_signed(|hash| {
375 Secp256k1::new().sign_recoverable(hash, &private_key)
380 fn zero_value_invoice(payment_preimage: PaymentPreimage) -> Invoice {
381 let payment_hash = Sha256::hash(&payment_preimage.0);
382 let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
383 InvoiceBuilder::new(Currency::Bitcoin)
384 .description("test".into())
385 .payment_hash(payment_hash)
386 .payment_secret(PaymentSecret([0; 32]))
388 .min_final_cltv_expiry(144)
389 .build_signed(|hash| {
390 Secp256k1::new().sign_recoverable(hash, &private_key)
395 fn expired_invoice(payment_preimage: PaymentPreimage) -> Invoice {
396 let payment_hash = Sha256::hash(&payment_preimage.0);
397 let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
398 let timestamp = SystemTime::now()
399 .checked_sub(Duration::from_secs(DEFAULT_EXPIRY_TIME * 2))
401 InvoiceBuilder::new(Currency::Bitcoin)
402 .description("test".into())
403 .payment_hash(payment_hash)
404 .payment_secret(PaymentSecret([0; 32]))
405 .timestamp(timestamp)
406 .min_final_cltv_expiry(144)
407 .amount_milli_satoshis(128)
408 .build_signed(|hash| {
409 Secp256k1::new().sign_recoverable(hash, &private_key)
415 fn pays_invoice_on_first_attempt() {
416 let event_handled = core::cell::RefCell::new(false);
417 let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
419 let payment_preimage = PaymentPreimage([1; 32]);
420 let invoice = invoice(payment_preimage);
421 let payment_hash = PaymentHash(invoice.payment_hash().clone().into_inner());
423 let payer = TestPayer::new();
424 let router = TestRouter {};
425 let logger = TestLogger::new();
427 InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(0));
429 let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap());
430 assert_eq!(*payer.attempts.borrow(), 1);
432 invoice_payer.handle_event(&Event::PaymentSent {
433 payment_id, payment_preimage, payment_hash, fee_paid_msat: None
435 assert_eq!(*event_handled.borrow(), true);
436 assert_eq!(*payer.attempts.borrow(), 1);
440 fn pays_invoice_on_retry() {
441 let event_handled = core::cell::RefCell::new(false);
442 let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
444 let payment_preimage = PaymentPreimage([1; 32]);
445 let invoice = invoice(payment_preimage);
446 let payment_hash = PaymentHash(invoice.payment_hash().clone().into_inner());
447 let final_value_msat = invoice.amount_milli_satoshis().unwrap();
449 let payer = TestPayer::new()
450 .expect_value_msat(final_value_msat)
451 .expect_value_msat(final_value_msat / 2);
452 let router = TestRouter {};
453 let logger = TestLogger::new();
455 InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2));
457 let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap());
458 assert_eq!(*payer.attempts.borrow(), 1);
460 let event = Event::PaymentPathFailed {
463 network_update: None,
464 rejected_by_dest: false,
465 all_paths_failed: false,
466 path: TestRouter::path_for_value(final_value_msat),
467 short_channel_id: None,
468 retry: Some(TestRouter::retry_for_invoice(&invoice)),
470 invoice_payer.handle_event(&event);
471 assert_eq!(*event_handled.borrow(), false);
472 assert_eq!(*payer.attempts.borrow(), 2);
474 invoice_payer.handle_event(&Event::PaymentSent {
475 payment_id, payment_preimage, payment_hash, fee_paid_msat: None
477 assert_eq!(*event_handled.borrow(), true);
478 assert_eq!(*payer.attempts.borrow(), 2);
482 fn retries_payment_path_for_unknown_payment() {
483 let event_handled = core::cell::RefCell::new(false);
484 let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
486 let payment_preimage = PaymentPreimage([1; 32]);
487 let invoice = invoice(payment_preimage);
488 let payment_hash = PaymentHash(invoice.payment_hash().clone().into_inner());
489 let final_value_msat = invoice.amount_milli_satoshis().unwrap();
491 let payer = TestPayer::new();
492 let router = TestRouter {};
493 let logger = TestLogger::new();
495 InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2));
497 let payment_id = Some(PaymentId([1; 32]));
498 let event = Event::PaymentPathFailed {
501 network_update: None,
502 rejected_by_dest: false,
503 all_paths_failed: false,
504 path: TestRouter::path_for_value(final_value_msat),
505 short_channel_id: None,
506 retry: Some(TestRouter::retry_for_invoice(&invoice)),
508 invoice_payer.handle_event(&event);
509 assert_eq!(*event_handled.borrow(), false);
510 assert_eq!(*payer.attempts.borrow(), 1);
512 invoice_payer.handle_event(&event);
513 assert_eq!(*event_handled.borrow(), false);
514 assert_eq!(*payer.attempts.borrow(), 2);
516 invoice_payer.handle_event(&Event::PaymentSent {
517 payment_id, payment_preimage, payment_hash, fee_paid_msat: None
519 assert_eq!(*event_handled.borrow(), true);
520 assert_eq!(*payer.attempts.borrow(), 2);
524 fn fails_paying_invoice_after_max_retries() {
525 let event_handled = core::cell::RefCell::new(false);
526 let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
528 let payment_preimage = PaymentPreimage([1; 32]);
529 let invoice = invoice(payment_preimage);
530 let final_value_msat = invoice.amount_milli_satoshis().unwrap();
532 let payer = TestPayer::new()
533 .expect_value_msat(final_value_msat)
534 .expect_value_msat(final_value_msat / 2)
535 .expect_value_msat(final_value_msat / 2);
536 let router = TestRouter {};
537 let logger = TestLogger::new();
539 InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2));
541 let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap());
542 assert_eq!(*payer.attempts.borrow(), 1);
544 let event = Event::PaymentPathFailed {
546 payment_hash: PaymentHash(invoice.payment_hash().clone().into_inner()),
547 network_update: None,
548 rejected_by_dest: false,
549 all_paths_failed: true,
550 path: TestRouter::path_for_value(final_value_msat),
551 short_channel_id: None,
552 retry: Some(TestRouter::retry_for_invoice(&invoice)),
554 invoice_payer.handle_event(&event);
555 assert_eq!(*event_handled.borrow(), false);
556 assert_eq!(*payer.attempts.borrow(), 2);
558 let event = Event::PaymentPathFailed {
560 payment_hash: PaymentHash(invoice.payment_hash().clone().into_inner()),
561 network_update: None,
562 rejected_by_dest: false,
563 all_paths_failed: false,
564 path: TestRouter::path_for_value(final_value_msat / 2),
565 short_channel_id: None,
566 retry: Some(RouteParameters {
567 final_value_msat: final_value_msat / 2, ..TestRouter::retry_for_invoice(&invoice)
570 invoice_payer.handle_event(&event);
571 assert_eq!(*event_handled.borrow(), false);
572 assert_eq!(*payer.attempts.borrow(), 3);
574 invoice_payer.handle_event(&event);
575 assert_eq!(*event_handled.borrow(), true);
576 assert_eq!(*payer.attempts.borrow(), 3);
580 fn fails_paying_invoice_with_missing_retry_params() {
581 let event_handled = core::cell::RefCell::new(false);
582 let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
584 let payer = TestPayer::new();
585 let router = TestRouter {};
586 let logger = TestLogger::new();
588 InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2));
590 let payment_preimage = PaymentPreimage([1; 32]);
591 let invoice = invoice(payment_preimage);
592 let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap());
593 assert_eq!(*payer.attempts.borrow(), 1);
595 let event = Event::PaymentPathFailed {
597 payment_hash: PaymentHash(invoice.payment_hash().clone().into_inner()),
598 network_update: None,
599 rejected_by_dest: false,
600 all_paths_failed: false,
602 short_channel_id: None,
605 invoice_payer.handle_event(&event);
606 assert_eq!(*event_handled.borrow(), true);
607 assert_eq!(*payer.attempts.borrow(), 1);
611 fn fails_paying_invoice_after_expiration() {
612 let event_handled = core::cell::RefCell::new(false);
613 let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
615 let payer = TestPayer::new();
616 let router = TestRouter {};
617 let logger = TestLogger::new();
619 InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2));
621 let payment_preimage = PaymentPreimage([1; 32]);
622 let invoice = expired_invoice(payment_preimage);
623 let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap());
624 assert_eq!(*payer.attempts.borrow(), 1);
626 let event = Event::PaymentPathFailed {
628 payment_hash: PaymentHash(invoice.payment_hash().clone().into_inner()),
629 network_update: None,
630 rejected_by_dest: false,
631 all_paths_failed: false,
633 short_channel_id: None,
634 retry: Some(TestRouter::retry_for_invoice(&invoice)),
636 invoice_payer.handle_event(&event);
637 assert_eq!(*event_handled.borrow(), true);
638 assert_eq!(*payer.attempts.borrow(), 1);
642 fn fails_paying_invoice_after_retry_error() {
643 let event_handled = core::cell::RefCell::new(false);
644 let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
646 let payment_preimage = PaymentPreimage([1; 32]);
647 let invoice = invoice(payment_preimage);
648 let final_value_msat = invoice.amount_milli_satoshis().unwrap();
650 let payer = TestPayer::new()
652 .expect_value_msat(final_value_msat);
653 let router = TestRouter {};
654 let logger = TestLogger::new();
656 InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2));
658 let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap());
659 assert_eq!(*payer.attempts.borrow(), 1);
661 let event = Event::PaymentPathFailed {
663 payment_hash: PaymentHash(invoice.payment_hash().clone().into_inner()),
664 network_update: None,
665 rejected_by_dest: false,
666 all_paths_failed: false,
667 path: TestRouter::path_for_value(final_value_msat / 2),
668 short_channel_id: None,
669 retry: Some(TestRouter::retry_for_invoice(&invoice)),
671 invoice_payer.handle_event(&event);
672 assert_eq!(*event_handled.borrow(), true);
673 assert_eq!(*payer.attempts.borrow(), 2);
677 fn fails_paying_invoice_after_rejected_by_payee() {
678 let event_handled = core::cell::RefCell::new(false);
679 let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
681 let payer = TestPayer::new();
682 let router = TestRouter {};
683 let logger = TestLogger::new();
685 InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2));
687 let payment_preimage = PaymentPreimage([1; 32]);
688 let invoice = invoice(payment_preimage);
689 let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap());
690 assert_eq!(*payer.attempts.borrow(), 1);
692 let event = Event::PaymentPathFailed {
694 payment_hash: PaymentHash(invoice.payment_hash().clone().into_inner()),
695 network_update: None,
696 rejected_by_dest: true,
697 all_paths_failed: false,
699 short_channel_id: None,
700 retry: Some(TestRouter::retry_for_invoice(&invoice)),
702 invoice_payer.handle_event(&event);
703 assert_eq!(*event_handled.borrow(), true);
704 assert_eq!(*payer.attempts.borrow(), 1);
708 fn fails_repaying_invoice_with_pending_payment() {
709 let event_handled = core::cell::RefCell::new(false);
710 let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
712 let payer = TestPayer::new();
713 let router = TestRouter {};
714 let logger = TestLogger::new();
716 InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(0));
718 let payment_preimage = PaymentPreimage([1; 32]);
719 let invoice = invoice(payment_preimage);
720 let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap());
722 // Cannot repay an invoice pending payment.
723 match invoice_payer.pay_invoice(&invoice) {
724 Err(PaymentError::Invoice("payment pending")) => {},
725 Err(_) => panic!("unexpected error"),
726 Ok(_) => panic!("expected invoice error"),
729 // Can repay an invoice once cleared from cache.
730 let payment_hash = PaymentHash(invoice.payment_hash().clone().into_inner());
731 invoice_payer.remove_cached_payment(&payment_hash);
732 assert!(invoice_payer.pay_invoice(&invoice).is_ok());
734 // Cannot retry paying an invoice if cleared from cache.
735 invoice_payer.remove_cached_payment(&payment_hash);
736 let event = Event::PaymentPathFailed {
739 network_update: None,
740 rejected_by_dest: false,
741 all_paths_failed: false,
743 short_channel_id: None,
744 retry: Some(TestRouter::retry_for_invoice(&invoice)),
746 invoice_payer.handle_event(&event);
747 assert_eq!(*event_handled.borrow(), true);
751 fn fails_paying_invoice_with_routing_errors() {
752 let payer = TestPayer::new();
753 let router = FailingRouter {};
754 let logger = TestLogger::new();
756 InvoicePayer::new(&payer, router, &logger, |_: &_| {}, RetryAttempts(0));
758 let payment_preimage = PaymentPreimage([1; 32]);
759 let invoice = invoice(payment_preimage);
760 match invoice_payer.pay_invoice(&invoice) {
761 Err(PaymentError::Routing(_)) => {},
762 Err(_) => panic!("unexpected error"),
763 Ok(_) => panic!("expected routing error"),
768 fn fails_paying_invoice_with_sending_errors() {
769 let payer = TestPayer::new().fails_on_attempt(1);
770 let router = TestRouter {};
771 let logger = TestLogger::new();
773 InvoicePayer::new(&payer, router, &logger, |_: &_| {}, RetryAttempts(0));
775 let payment_preimage = PaymentPreimage([1; 32]);
776 let invoice = invoice(payment_preimage);
777 match invoice_payer.pay_invoice(&invoice) {
778 Err(PaymentError::Sending(_)) => {},
779 Err(_) => panic!("unexpected error"),
780 Ok(_) => panic!("expected sending error"),
785 fn pays_zero_value_invoice_using_amount() {
786 let event_handled = core::cell::RefCell::new(false);
787 let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
789 let payment_preimage = PaymentPreimage([1; 32]);
790 let invoice = zero_value_invoice(payment_preimage);
791 let payment_hash = PaymentHash(invoice.payment_hash().clone().into_inner());
792 let final_value_msat = 100;
794 let payer = TestPayer::new().expect_value_msat(final_value_msat);
795 let router = TestRouter {};
796 let logger = TestLogger::new();
798 InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(0));
801 Some(invoice_payer.pay_zero_value_invoice(&invoice, final_value_msat).unwrap());
802 assert_eq!(*payer.attempts.borrow(), 1);
804 invoice_payer.handle_event(&Event::PaymentSent {
805 payment_id, payment_preimage, payment_hash, fee_paid_msat: None
807 assert_eq!(*event_handled.borrow(), true);
808 assert_eq!(*payer.attempts.borrow(), 1);
812 fn fails_paying_zero_value_invoice_with_amount() {
813 let event_handled = core::cell::RefCell::new(false);
814 let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
816 let payer = TestPayer::new();
817 let router = TestRouter {};
818 let logger = TestLogger::new();
820 InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(0));
822 let payment_preimage = PaymentPreimage([1; 32]);
823 let invoice = invoice(payment_preimage);
825 // Cannot repay an invoice pending payment.
826 match invoice_payer.pay_zero_value_invoice(&invoice, 100) {
827 Err(PaymentError::Invoice("amount unexpected")) => {},
828 Err(_) => panic!("unexpected error"),
829 Ok(_) => panic!("expected invoice error"),
836 fn route_for_value(final_value_msat: u64) -> Route {
840 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
841 channel_features: ChannelFeatures::empty(),
842 node_features: NodeFeatures::empty(),
843 short_channel_id: 0, fee_msat: final_value_msat / 2, cltv_expiry_delta: 144
846 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
847 channel_features: ChannelFeatures::empty(),
848 node_features: NodeFeatures::empty(),
849 short_channel_id: 1, fee_msat: final_value_msat / 2, cltv_expiry_delta: 144
856 fn path_for_value(final_value_msat: u64) -> Vec<RouteHop> {
857 TestRouter::route_for_value(final_value_msat).paths[0].clone()
860 fn retry_for_invoice(invoice: &Invoice) -> RouteParameters {
861 let mut payee = Payee::new(invoice.recover_payee_pub_key())
862 .with_expiry_time(expiry_time_from_unix_epoch(invoice).as_secs())
863 .with_route_hints(invoice.route_hints());
864 if let Some(features) = invoice.features() {
865 payee = payee.with_features(features.clone());
867 let final_value_msat = invoice.amount_milli_satoshis().unwrap() / 2;
871 final_cltv_expiry_delta: invoice.min_final_cltv_expiry() as u32,
876 impl Router for TestRouter {
880 params: &RouteParameters,
881 _first_hops: Option<&[&ChannelDetails]>,
882 ) -> Result<Route, LightningError> {
884 payee: Some(params.payee.clone()), ..Self::route_for_value(params.final_value_msat)
889 struct FailingRouter;
891 impl Router for FailingRouter {
895 _params: &RouteParameters,
896 _first_hops: Option<&[&ChannelDetails]>,
897 ) -> Result<Route, LightningError> {
898 Err(LightningError { err: String::new(), action: ErrorAction::IgnoreError })
903 expectations: core::cell::RefCell<std::collections::VecDeque<u64>>,
904 attempts: core::cell::RefCell<usize>,
905 failing_on_attempt: Option<usize>,
911 expectations: core::cell::RefCell::new(std::collections::VecDeque::new()),
912 attempts: core::cell::RefCell::new(0),
913 failing_on_attempt: None,
917 fn expect_value_msat(self, value_msat: u64) -> Self {
918 self.expectations.borrow_mut().push_back(value_msat);
922 fn fails_on_attempt(self, attempt: usize) -> Self {
924 expectations: core::cell::RefCell::new(self.expectations.borrow().clone()),
925 attempts: core::cell::RefCell::new(0),
926 failing_on_attempt: Some(attempt),
930 fn check_attempts(&self) -> bool {
931 let mut attempts = self.attempts.borrow_mut();
933 match self.failing_on_attempt {
935 Some(attempt) if attempt != *attempts => true,
940 fn check_value_msats(&self, route: &Route) {
941 let expected_value_msats = self.expectations.borrow_mut().pop_front();
942 if let Some(expected_value_msats) = expected_value_msats {
943 let actual_value_msats = route.get_total_amount();
944 assert_eq!(actual_value_msats, expected_value_msats);
949 impl Drop for TestPayer {
951 if std::thread::panicking() {
955 if !self.expectations.borrow().is_empty() {
956 panic!("Unsatisfied payment expectations: {:?}", self.expectations.borrow());
961 impl Payer for TestPayer {
962 fn node_id(&self) -> PublicKey {
963 let secp_ctx = Secp256k1::new();
964 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
967 fn first_hops(&self) -> Vec<ChannelDetails> {
974 _payment_hash: PaymentHash,
975 _payment_secret: &Option<PaymentSecret>
976 ) -> Result<PaymentId, PaymentSendFailure> {
977 if self.check_attempts() {
978 self.check_value_msats(route);
979 Ok(PaymentId([1; 32]))
981 Err(PaymentSendFailure::ParameterError(APIError::MonitorUpdateFailed))
986 &self, route: &Route, _payment_id: PaymentId
987 ) -> Result<(), PaymentSendFailure> {
988 if self.check_attempts() {
989 self.check_value_msats(route);
992 Err(PaymentSendFailure::ParameterError(APIError::MonitorUpdateFailed))