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 //! Events are returned from various bits in the library which indicate some action must be taken
13 //! Because we don't have a built-in runtime, it's up to the client to call events at a time in the
14 //! future, as well as generate and broadcast funding transactions handle payment preimages and a
17 pub mod bump_transaction;
19 pub use bump_transaction::BumpTransactionEvent;
21 use crate::blinded_path::payment::{Bolt12OfferContext, Bolt12RefundContext, PaymentContext, PaymentContextRef};
22 use crate::chain::transaction;
23 use crate::ln::channelmanager::{InterceptId, PaymentId, RecipientOnionFields};
24 use crate::ln::channel::FUNDING_CONF_DEADLINE_BLOCKS;
25 use crate::ln::features::ChannelTypeFeatures;
27 use crate::ln::types::{ChannelId, PaymentPreimage, PaymentHash, PaymentSecret};
28 use crate::offers::invoice::Bolt12Invoice;
29 use crate::onion_message::messenger::Responder;
30 use crate::routing::gossip::NetworkUpdate;
31 use crate::routing::router::{BlindedTail, Path, RouteHop, RouteParameters};
32 use crate::sign::SpendableOutputDescriptor;
33 use crate::util::errors::APIError;
34 use crate::util::ser::{BigSize, FixedLengthReader, Writeable, Writer, MaybeReadable, Readable, RequiredWrapper, UpgradableRequired, WithoutLength};
35 use crate::util::string::UntrustedString;
37 use bitcoin::{Transaction, OutPoint};
38 use bitcoin::blockdata::locktime::absolute::LockTime;
39 use bitcoin::blockdata::script::ScriptBuf;
40 use bitcoin::hashes::Hash;
41 use bitcoin::hashes::sha256::Hash as Sha256;
42 use bitcoin::secp256k1::PublicKey;
43 use bitcoin::transaction::Version;
45 use core::time::Duration;
49 #[allow(unused_imports)]
50 use crate::prelude::*;
52 /// Some information provided on receipt of payment depends on whether the payment received is a
53 /// spontaneous payment or a "conventional" lightning payment that's paying an invoice.
54 #[derive(Clone, Debug, PartialEq, Eq)]
55 pub enum PaymentPurpose {
56 /// A payment for a BOLT 11 invoice.
57 Bolt11InvoicePayment {
58 /// The preimage to the payment_hash, if the payment hash (and secret) were fetched via
59 /// [`ChannelManager::create_inbound_payment`]. When handling [`Event::PaymentClaimable`],
60 /// this can be passed directly to [`ChannelManager::claim_funds`] to claim the payment. No
61 /// action is needed when seen in [`Event::PaymentClaimed`].
63 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
64 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
65 payment_preimage: Option<PaymentPreimage>,
66 /// The "payment secret". This authenticates the sender to the recipient, preventing a
67 /// number of deanonymization attacks during the routing process.
68 /// It is provided here for your reference, however its accuracy is enforced directly by
69 /// [`ChannelManager`] using the values you previously provided to
70 /// [`ChannelManager::create_inbound_payment`] or
71 /// [`ChannelManager::create_inbound_payment_for_hash`].
73 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
74 /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
75 /// [`ChannelManager::create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
76 payment_secret: PaymentSecret,
78 /// A payment for a BOLT 12 [`Offer`].
80 /// [`Offer`]: crate::offers::offer::Offer
82 /// The preimage to the payment hash. When handling [`Event::PaymentClaimable`], this can be
83 /// passed directly to [`ChannelManager::claim_funds`], if provided. No action is needed
84 /// when seen in [`Event::PaymentClaimed`].
86 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
87 payment_preimage: Option<PaymentPreimage>,
88 /// The secret used to authenticate the sender to the recipient, preventing a number of
89 /// de-anonymization attacks while routing a payment.
91 /// See [`PaymentPurpose::Bolt11InvoicePayment::payment_secret`] for further details.
92 payment_secret: PaymentSecret,
93 /// The context of the payment such as information about the corresponding [`Offer`] and
94 /// [`InvoiceRequest`].
96 /// [`Offer`]: crate::offers::offer::Offer
97 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
98 payment_context: Bolt12OfferContext,
100 /// A payment for a BOLT 12 [`Refund`].
102 /// [`Refund`]: crate::offers::refund::Refund
103 Bolt12RefundPayment {
104 /// The preimage to the payment hash. When handling [`Event::PaymentClaimable`], this can be
105 /// passed directly to [`ChannelManager::claim_funds`], if provided. No action is needed
106 /// when seen in [`Event::PaymentClaimed`].
108 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
109 payment_preimage: Option<PaymentPreimage>,
110 /// The secret used to authenticate the sender to the recipient, preventing a number of
111 /// de-anonymization attacks while routing a payment.
113 /// See [`PaymentPurpose::Bolt11InvoicePayment::payment_secret`] for further details.
114 payment_secret: PaymentSecret,
115 /// The context of the payment such as information about the corresponding [`Refund`].
117 /// [`Refund`]: crate::offers::refund::Refund
118 payment_context: Bolt12RefundContext,
120 /// Because this is a spontaneous payment, the payer generated their own preimage rather than us
121 /// (the payee) providing a preimage.
122 SpontaneousPayment(PaymentPreimage),
125 impl PaymentPurpose {
126 /// Returns the preimage for this payment, if it is known.
127 pub fn preimage(&self) -> Option<PaymentPreimage> {
129 PaymentPurpose::Bolt11InvoicePayment { payment_preimage, .. } => *payment_preimage,
130 PaymentPurpose::Bolt12OfferPayment { payment_preimage, .. } => *payment_preimage,
131 PaymentPurpose::Bolt12RefundPayment { payment_preimage, .. } => *payment_preimage,
132 PaymentPurpose::SpontaneousPayment(preimage) => Some(*preimage),
136 pub(crate) fn is_keysend(&self) -> bool {
138 PaymentPurpose::Bolt11InvoicePayment { .. } => false,
139 PaymentPurpose::Bolt12OfferPayment { .. } => false,
140 PaymentPurpose::Bolt12RefundPayment { .. } => false,
141 PaymentPurpose::SpontaneousPayment(..) => true,
145 pub(crate) fn from_parts(
146 payment_preimage: Option<PaymentPreimage>, payment_secret: PaymentSecret,
147 payment_context: Option<PaymentContext>,
149 match payment_context {
150 Some(PaymentContext::Unknown(_)) | None => {
151 PaymentPurpose::Bolt11InvoicePayment {
156 Some(PaymentContext::Bolt12Offer(context)) => {
157 PaymentPurpose::Bolt12OfferPayment {
160 payment_context: context,
163 Some(PaymentContext::Bolt12Refund(context)) => {
164 PaymentPurpose::Bolt12RefundPayment {
167 payment_context: context,
174 impl_writeable_tlv_based_enum!(PaymentPurpose,
175 (0, Bolt11InvoicePayment) => {
176 (0, payment_preimage, option),
177 (2, payment_secret, required),
179 (4, Bolt12OfferPayment) => {
180 (0, payment_preimage, option),
181 (2, payment_secret, required),
182 (4, payment_context, required),
184 (6, Bolt12RefundPayment) => {
185 (0, payment_preimage, option),
186 (2, payment_secret, required),
187 (4, payment_context, required),
190 (2, SpontaneousPayment)
193 /// Information about an HTLC that is part of a payment that can be claimed.
194 #[derive(Clone, Debug, PartialEq, Eq)]
195 pub struct ClaimedHTLC {
196 /// The `channel_id` of the channel over which the HTLC was received.
197 pub channel_id: ChannelId,
198 /// The `user_channel_id` of the channel over which the HTLC was received. This is the value
199 /// passed in to [`ChannelManager::create_channel`] for outbound channels, or to
200 /// [`ChannelManager::accept_inbound_channel`] for inbound channels if
201 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
202 /// `user_channel_id` will be randomized for an inbound channel.
204 /// This field will be zero for a payment that was serialized prior to LDK version 0.0.117. (This
205 /// should only happen in the case that a payment was claimable prior to LDK version 0.0.117, but
206 /// was not actually claimed until after upgrading.)
208 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
209 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
210 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
211 pub user_channel_id: u128,
212 /// The block height at which this HTLC expires.
213 pub cltv_expiry: u32,
214 /// The amount (in msats) of this part of an MPP.
216 /// The extra fee our counterparty skimmed off the top of this HTLC, if any.
218 /// This value will always be 0 for [`ClaimedHTLC`]s serialized with LDK versions prior to
220 pub counterparty_skimmed_fee_msat: u64,
222 impl_writeable_tlv_based!(ClaimedHTLC, {
223 (0, channel_id, required),
224 (1, counterparty_skimmed_fee_msat, (default_value, 0u64)),
225 (2, user_channel_id, required),
226 (4, cltv_expiry, required),
227 (6, value_msat, required),
230 /// When the payment path failure took place and extra details about it. [`PathFailure::OnPath`] may
231 /// contain a [`NetworkUpdate`] that needs to be applied to the [`NetworkGraph`].
233 /// [`NetworkUpdate`]: crate::routing::gossip::NetworkUpdate
234 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
235 #[derive(Clone, Debug, Eq, PartialEq)]
236 pub enum PathFailure {
237 /// We failed to initially send the payment and no HTLC was committed to. Contains the relevant
240 /// The error surfaced from initial send.
243 /// A hop on the path failed to forward our payment.
245 /// If present, this [`NetworkUpdate`] should be applied to the [`NetworkGraph`] so that routing
246 /// decisions can take into account the update.
248 /// [`NetworkUpdate`]: crate::routing::gossip::NetworkUpdate
249 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
250 network_update: Option<NetworkUpdate>,
254 impl_writeable_tlv_based_enum_upgradable!(PathFailure,
256 (0, network_update, upgradable_option),
258 (2, InitialSend) => {
259 (0, err, upgradable_required),
263 #[derive(Clone, Debug, PartialEq, Eq)]
264 /// The reason the channel was closed. See individual variants for more details.
265 pub enum ClosureReason {
266 /// Closure generated from receiving a peer error message.
268 /// Our counterparty may have broadcasted their latest commitment state, and we have
270 CounterpartyForceClosed {
271 /// The error which the peer sent us.
273 /// Be careful about printing the peer_msg, a well-crafted message could exploit
274 /// a security vulnerability in the terminal emulator or the logging subsystem.
275 /// To be safe, use `Display` on `UntrustedString`
277 /// [`UntrustedString`]: crate::util::string::UntrustedString
278 peer_msg: UntrustedString,
280 /// Closure generated from [`ChannelManager::force_close_channel`], called by the user.
282 /// [`ChannelManager::force_close_channel`]: crate::ln::channelmanager::ChannelManager::force_close_channel.
284 /// Whether or not the latest transaction was broadcasted when the channel was force
287 /// Channels closed using [`ChannelManager::force_close_broadcasting_latest_txn`] will have
288 /// this field set to true, whereas channels closed using [`ChannelManager::force_close_without_broadcasting_txn`]
289 /// or force-closed prior to being funded will have this field set to false.
291 /// This will be `None` for objects generated or written by LDK 0.0.123 and
294 /// [`ChannelManager::force_close_broadcasting_latest_txn`]: crate::ln::channelmanager::ChannelManager::force_close_broadcasting_latest_txn.
295 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn.
296 broadcasted_latest_txn: Option<bool>
298 /// The channel was closed after negotiating a cooperative close and we've now broadcasted
299 /// the cooperative close transaction. Note the shutdown may have been initiated by us.
301 /// This was only set in versions of LDK prior to 0.0.122.
302 // Can be removed once we disallow downgrading to 0.0.121
303 LegacyCooperativeClosure,
304 /// The channel was closed after negotiating a cooperative close and we've now broadcasted
305 /// the cooperative close transaction. This indicates that the shutdown was initiated by our
308 /// In rare cases where we initiated closure immediately prior to shutting down without
309 /// persisting, this value may be provided for channels we initiated closure for.
310 CounterpartyInitiatedCooperativeClosure,
311 /// The channel was closed after negotiating a cooperative close and we've now broadcasted
312 /// the cooperative close transaction. This indicates that the shutdown was initiated by us.
313 LocallyInitiatedCooperativeClosure,
314 /// A commitment transaction was confirmed on chain, closing the channel. Most likely this
315 /// commitment transaction came from our counterparty, but it may also have come from
316 /// a copy of our own `ChannelMonitor`.
317 CommitmentTxConfirmed,
318 /// The funding transaction failed to confirm in a timely manner on an inbound channel.
320 /// Closure generated from processing an event, likely a HTLC forward/relay/reception.
322 /// A developer-readable error message which we generated.
325 /// The peer disconnected prior to funding completing. In this case the spec mandates that we
326 /// forget the channel entirely - we can attempt again if the peer reconnects.
328 /// This includes cases where we restarted prior to funding completion, including prior to the
329 /// initial [`ChannelMonitor`] persistence completing.
331 /// In LDK versions prior to 0.0.107 this could also occur if we were unable to connect to the
332 /// peer because of mutual incompatibility between us and our channel counterparty.
334 /// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
336 /// Closure generated from `ChannelManager::read` if the [`ChannelMonitor`] is newer than
337 /// the [`ChannelManager`] deserialized.
339 /// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
340 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
341 OutdatedChannelManager,
342 /// The counterparty requested a cooperative close of a channel that had not been funded yet.
343 /// The channel has been immediately closed.
344 CounterpartyCoopClosedUnfundedChannel,
345 /// Another channel in the same funding batch closed before the funding transaction
346 /// was ready to be broadcast.
348 /// One of our HTLCs timed out in a channel, causing us to force close the channel.
350 /// Our peer provided a feerate which violated our required minimum (fetched from our
351 /// [`FeeEstimator`] either as [`ConfirmationTarget::MinAllowedAnchorChannelRemoteFee`] or
352 /// [`ConfirmationTarget::MinAllowedNonAnchorChannelRemoteFee`]).
354 /// [`FeeEstimator`]: crate::chain::chaininterface::FeeEstimator
355 /// [`ConfirmationTarget::MinAllowedAnchorChannelRemoteFee`]: crate::chain::chaininterface::ConfirmationTarget::MinAllowedAnchorChannelRemoteFee
356 /// [`ConfirmationTarget::MinAllowedNonAnchorChannelRemoteFee`]: crate::chain::chaininterface::ConfirmationTarget::MinAllowedNonAnchorChannelRemoteFee
358 /// The feerate on our channel set by our peer.
359 peer_feerate_sat_per_kw: u32,
360 /// The required feerate we enforce, from our [`FeeEstimator`].
362 /// [`FeeEstimator`]: crate::chain::chaininterface::FeeEstimator
363 required_feerate_sat_per_kw: u32,
367 impl core::fmt::Display for ClosureReason {
368 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
369 f.write_str("Channel closed because ")?;
371 ClosureReason::CounterpartyForceClosed { peer_msg } => {
372 f.write_fmt(format_args!("counterparty force-closed with message: {}", peer_msg))
374 ClosureReason::HolderForceClosed { broadcasted_latest_txn } => {
375 f.write_str("user force-closed the channel")?;
376 if let Some(brodcasted) = broadcasted_latest_txn {
377 write!(f, " and {} the latest transaction", if *brodcasted { "broadcasted" } else { "elected not to broadcast" })
382 ClosureReason::LegacyCooperativeClosure => f.write_str("the channel was cooperatively closed"),
383 ClosureReason::CounterpartyInitiatedCooperativeClosure => f.write_str("the channel was cooperatively closed by our peer"),
384 ClosureReason::LocallyInitiatedCooperativeClosure => f.write_str("the channel was cooperatively closed by us"),
385 ClosureReason::CommitmentTxConfirmed => f.write_str("commitment or closing transaction was confirmed on chain."),
386 ClosureReason::FundingTimedOut => write!(f, "funding transaction failed to confirm within {} blocks", FUNDING_CONF_DEADLINE_BLOCKS),
387 ClosureReason::ProcessingError { err } => {
388 f.write_str("of an exception: ")?;
391 ClosureReason::DisconnectedPeer => f.write_str("the peer disconnected prior to the channel being funded"),
392 ClosureReason::OutdatedChannelManager => f.write_str("the ChannelManager read from disk was stale compared to ChannelMonitor(s)"),
393 ClosureReason::CounterpartyCoopClosedUnfundedChannel => f.write_str("the peer requested the unfunded channel be closed"),
394 ClosureReason::FundingBatchClosure => f.write_str("another channel in the same funding batch closed"),
395 ClosureReason::HTLCsTimedOut => f.write_str("htlcs on the channel timed out"),
396 ClosureReason::PeerFeerateTooLow { peer_feerate_sat_per_kw, required_feerate_sat_per_kw } =>
397 f.write_fmt(format_args!(
398 "peer provided a feerate ({} sat/kw) which was below our lower bound ({} sat/kw)",
399 peer_feerate_sat_per_kw, required_feerate_sat_per_kw,
405 impl_writeable_tlv_based_enum_upgradable!(ClosureReason,
406 (0, CounterpartyForceClosed) => { (1, peer_msg, required) },
407 (1, FundingTimedOut) => {},
408 (2, HolderForceClosed) => { (1, broadcasted_latest_txn, option) },
409 (6, CommitmentTxConfirmed) => {},
410 (4, LegacyCooperativeClosure) => {},
411 (8, ProcessingError) => { (1, err, required) },
412 (10, DisconnectedPeer) => {},
413 (12, OutdatedChannelManager) => {},
414 (13, CounterpartyCoopClosedUnfundedChannel) => {},
415 (15, FundingBatchClosure) => {},
416 (17, CounterpartyInitiatedCooperativeClosure) => {},
417 (19, LocallyInitiatedCooperativeClosure) => {},
418 (21, HTLCsTimedOut) => {},
419 (23, PeerFeerateTooLow) => {
420 (0, peer_feerate_sat_per_kw, required),
421 (2, required_feerate_sat_per_kw, required),
425 /// Intended destination of a failed HTLC as indicated in [`Event::HTLCHandlingFailed`].
426 #[derive(Clone, Debug, PartialEq, Eq)]
427 pub enum HTLCDestination {
428 /// We tried forwarding to a channel but failed to do so. An example of such an instance is when
429 /// there is insufficient capacity in our outbound channel.
431 /// The `node_id` of the next node. For backwards compatibility, this field is
432 /// marked as optional, versions prior to 0.0.110 may not always be able to provide
433 /// counterparty node information.
434 node_id: Option<PublicKey>,
435 /// The outgoing `channel_id` between us and the next node.
436 channel_id: ChannelId,
438 /// Scenario where we are unsure of the next node to forward the HTLC to.
440 /// Short channel id we are requesting to forward an HTLC to.
441 requested_forward_scid: u64,
443 /// We couldn't forward to the outgoing scid. An example would be attempting to send a duplicate
446 /// Short channel id we are requesting to forward an HTLC to.
447 requested_forward_scid: u64
449 /// We couldn't decode the incoming onion to obtain the forwarding details.
451 /// Failure scenario where an HTLC may have been forwarded to be intended for us,
452 /// but is invalid for some reason, so we reject it.
454 /// Some of the reasons may include:
456 /// * Excess HTLCs for a payment that we have already fully received, over-paying for the
458 /// * The counterparty node modified the HTLC in transit,
459 /// * A probing attack where an intermediary node is trying to detect if we are the ultimate
460 /// recipient for a payment.
462 /// The payment hash of the payment we attempted to process.
463 payment_hash: PaymentHash
467 impl_writeable_tlv_based_enum_upgradable!(HTLCDestination,
468 (0, NextHopChannel) => {
469 (0, node_id, required),
470 (2, channel_id, required),
472 (1, InvalidForward) => {
473 (0, requested_forward_scid, required),
475 (2, UnknownNextHop) => {
476 (0, requested_forward_scid, required),
478 (3, InvalidOnion) => {},
479 (4, FailedPayment) => {
480 (0, payment_hash, required),
484 /// Will be used in [`Event::HTLCIntercepted`] to identify the next hop in the HTLC's path.
485 /// Currently only used in serialization for the sake of maintaining compatibility. More variants
486 /// will be added for general-purpose HTLC forward intercepts as well as trampoline forward
487 /// intercepts in upcoming work.
488 enum InterceptNextHop {
490 requested_next_hop_scid: u64,
494 impl_writeable_tlv_based_enum!(InterceptNextHop,
496 (0, requested_next_hop_scid, required),
500 /// The reason the payment failed. Used in [`Event::PaymentFailed`].
501 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
502 pub enum PaymentFailureReason {
503 /// The intended recipient rejected our payment.
505 /// The user chose to abandon this payment by calling [`ChannelManager::abandon_payment`].
507 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
509 /// We exhausted all of our retry attempts while trying to send the payment, or we
510 /// exhausted the [`Retry::Timeout`] if the user set one. If at any point a retry
511 /// attempt failed while being forwarded along the path, an [`Event::PaymentPathFailed`] will
512 /// have come before this.
514 /// [`Retry::Timeout`]: crate::ln::channelmanager::Retry::Timeout
516 /// The payment expired while retrying, based on the provided
517 /// [`PaymentParameters::expiry_time`].
519 /// [`PaymentParameters::expiry_time`]: crate::routing::router::PaymentParameters::expiry_time
521 /// We failed to find a route while retrying the payment.
523 /// Note that this generally indicates that we've exhausted the available set of possible
524 /// routes - we tried the payment over a few routes but were not able to find any further
525 /// candidate routes beyond those.
527 /// This error should generally never happen. This likely means that there is a problem with
532 impl_writeable_tlv_based_enum!(PaymentFailureReason,
533 (0, RecipientRejected) => {},
534 (2, UserAbandoned) => {},
535 (4, RetriesExhausted) => {},
536 (6, PaymentExpired) => {},
537 (8, RouteNotFound) => {},
538 (10, UnexpectedError) => {}, ;
541 /// An Event which you should probably take some action in response to.
543 /// Note that while Writeable and Readable are implemented for Event, you probably shouldn't use
544 /// them directly as they don't round-trip exactly (for example FundingGenerationReady is never
545 /// written as it makes no sense to respond to it after reconnecting to peers).
546 #[derive(Clone, Debug, PartialEq, Eq)]
548 /// Used to indicate that the client should generate a funding transaction with the given
549 /// parameters and then call [`ChannelManager::funding_transaction_generated`].
550 /// Generated in [`ChannelManager`] message handling.
551 /// Note that *all inputs* in the funding transaction must spend SegWit outputs or your
552 /// counterparty can steal your funds!
554 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
555 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
556 FundingGenerationReady {
557 /// The random channel_id we picked which you'll need to pass into
558 /// [`ChannelManager::funding_transaction_generated`].
560 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
561 temporary_channel_id: ChannelId,
562 /// The counterparty's node_id, which you'll need to pass back into
563 /// [`ChannelManager::funding_transaction_generated`].
565 /// [`ChannelManager::funding_transaction_generated`]: crate::ln::channelmanager::ChannelManager::funding_transaction_generated
566 counterparty_node_id: PublicKey,
567 /// The value, in satoshis, that the output should have.
568 channel_value_satoshis: u64,
569 /// The script which should be used in the transaction output.
570 output_script: ScriptBuf,
571 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`] for outbound
572 /// channels, or to [`ChannelManager::accept_inbound_channel`] for inbound channels if
573 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
574 /// `user_channel_id` will be randomized for an inbound channel. This may be zero for objects
575 /// serialized with LDK versions prior to 0.0.113.
577 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
578 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
579 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
580 user_channel_id: u128,
582 /// Indicates that we've been offered a payment and it needs to be claimed via calling
583 /// [`ChannelManager::claim_funds`] with the preimage given in [`PaymentPurpose`].
585 /// Note that if the preimage is not known, you should call
586 /// [`ChannelManager::fail_htlc_backwards`] or [`ChannelManager::fail_htlc_backwards_with_reason`]
587 /// to free up resources for this HTLC and avoid network congestion.
589 /// If [`Event::PaymentClaimable::onion_fields`] is `Some`, and includes custom TLVs with even type
590 /// numbers, you should use [`ChannelManager::fail_htlc_backwards_with_reason`] with
591 /// [`FailureCode::InvalidOnionPayload`] if you fail to understand and handle the contents, or
592 /// [`ChannelManager::claim_funds_with_known_custom_tlvs`] upon successful handling.
593 /// If you don't intend to check for custom TLVs, you can simply use
594 /// [`ChannelManager::claim_funds`], which will automatically fail back even custom TLVs.
596 /// If you fail to call [`ChannelManager::claim_funds`],
597 /// [`ChannelManager::claim_funds_with_known_custom_tlvs`],
598 /// [`ChannelManager::fail_htlc_backwards`], or
599 /// [`ChannelManager::fail_htlc_backwards_with_reason`] within the HTLC's timeout, the HTLC will
600 /// be automatically failed.
603 /// LDK will not stop an inbound payment from being paid multiple times, so multiple
604 /// `PaymentClaimable` events may be generated for the same payment. In such a case it is
605 /// polite (and required in the lightning specification) to fail the payment the second time
606 /// and give the sender their money back rather than accepting double payment.
609 /// This event used to be called `PaymentReceived` in LDK versions 0.0.112 and earlier.
611 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
612 /// [`ChannelManager::claim_funds_with_known_custom_tlvs`]: crate::ln::channelmanager::ChannelManager::claim_funds_with_known_custom_tlvs
613 /// [`FailureCode::InvalidOnionPayload`]: crate::ln::channelmanager::FailureCode::InvalidOnionPayload
614 /// [`ChannelManager::fail_htlc_backwards`]: crate::ln::channelmanager::ChannelManager::fail_htlc_backwards
615 /// [`ChannelManager::fail_htlc_backwards_with_reason`]: crate::ln::channelmanager::ChannelManager::fail_htlc_backwards_with_reason
617 /// The node that will receive the payment after it has been claimed.
618 /// This is useful to identify payments received via [phantom nodes].
619 /// This field will always be filled in when the event was generated by LDK versions
620 /// 0.0.113 and above.
622 /// [phantom nodes]: crate::sign::PhantomKeysManager
623 receiver_node_id: Option<PublicKey>,
624 /// The hash for which the preimage should be handed to the ChannelManager. Note that LDK will
625 /// not stop you from registering duplicate payment hashes for inbound payments.
626 payment_hash: PaymentHash,
627 /// The fields in the onion which were received with each HTLC. Only fields which were
628 /// identical in each HTLC involved in the payment will be included here.
630 /// Payments received on LDK versions prior to 0.0.115 will have this field unset.
631 onion_fields: Option<RecipientOnionFields>,
632 /// The value, in thousandths of a satoshi, that this payment is claimable for. May be greater
633 /// than the invoice amount.
635 /// May be less than the invoice amount if [`ChannelConfig::accept_underpaying_htlcs`] is set
636 /// and the previous hop took an extra fee.
639 /// If [`ChannelConfig::accept_underpaying_htlcs`] is set and you claim without verifying this
640 /// field, you may lose money!
642 /// [`ChannelConfig::accept_underpaying_htlcs`]: crate::util::config::ChannelConfig::accept_underpaying_htlcs
644 /// The value, in thousands of a satoshi, that was skimmed off of this payment as an extra fee
645 /// taken by our channel counterparty.
647 /// Will always be 0 unless [`ChannelConfig::accept_underpaying_htlcs`] is set.
649 /// [`ChannelConfig::accept_underpaying_htlcs`]: crate::util::config::ChannelConfig::accept_underpaying_htlcs
650 counterparty_skimmed_fee_msat: u64,
651 /// Information for claiming this received payment, based on whether the purpose of the
652 /// payment is to pay an invoice or to send a spontaneous payment.
653 purpose: PaymentPurpose,
654 /// The `channel_id` indicating over which channel we received the payment.
655 via_channel_id: Option<ChannelId>,
656 /// The `user_channel_id` indicating over which channel we received the payment.
657 via_user_channel_id: Option<u128>,
658 /// The block height at which this payment will be failed back and will no longer be
659 /// eligible for claiming.
661 /// Prior to this height, a call to [`ChannelManager::claim_funds`] is guaranteed to
662 /// succeed, however you should wait for [`Event::PaymentClaimed`] to be sure.
664 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
665 claim_deadline: Option<u32>,
667 /// Indicates a payment has been claimed and we've received money!
669 /// This most likely occurs when [`ChannelManager::claim_funds`] has been called in response
670 /// to an [`Event::PaymentClaimable`]. However, if we previously crashed during a
671 /// [`ChannelManager::claim_funds`] call you may see this event without a corresponding
672 /// [`Event::PaymentClaimable`] event.
675 /// LDK will not stop an inbound payment from being paid multiple times, so multiple
676 /// `PaymentClaimable` events may be generated for the same payment. If you then call
677 /// [`ChannelManager::claim_funds`] twice for the same [`Event::PaymentClaimable`] you may get
678 /// multiple `PaymentClaimed` events.
680 /// [`ChannelManager::claim_funds`]: crate::ln::channelmanager::ChannelManager::claim_funds
682 /// The node that received the payment.
683 /// This is useful to identify payments which were received via [phantom nodes].
684 /// This field will always be filled in when the event was generated by LDK versions
685 /// 0.0.113 and above.
687 /// [phantom nodes]: crate::sign::PhantomKeysManager
688 receiver_node_id: Option<PublicKey>,
689 /// The payment hash of the claimed payment. Note that LDK will not stop you from
690 /// registering duplicate payment hashes for inbound payments.
691 payment_hash: PaymentHash,
692 /// The value, in thousandths of a satoshi, that this payment is for. May be greater than the
695 /// The purpose of the claimed payment, i.e. whether the payment was for an invoice or a
696 /// spontaneous payment.
697 purpose: PaymentPurpose,
698 /// The HTLCs that comprise the claimed payment. This will be empty for events serialized prior
699 /// to LDK version 0.0.117.
700 htlcs: Vec<ClaimedHTLC>,
701 /// The sender-intended sum total of all the MPP parts. This will be `None` for events
702 /// serialized prior to LDK version 0.0.117.
703 sender_intended_total_msat: Option<u64>,
704 /// The fields in the onion which were received with each HTLC. Only fields which were
705 /// identical in each HTLC involved in the payment will be included here.
707 /// Payments received on LDK versions prior to 0.0.124 will have this field unset.
708 onion_fields: Option<RecipientOnionFields>,
710 /// Indicates that a peer connection with a node is needed in order to send an [`OnionMessage`].
712 /// Typically, this happens when a [`MessageRouter`] is unable to find a complete path to a
713 /// [`Destination`]. Once a connection is established, any messages buffered by an
714 /// [`OnionMessageHandler`] may be sent.
716 /// This event will not be generated for onion message forwards; only for sends including
717 /// replies. Handlers should connect to the node otherwise any buffered messages may be lost.
719 /// [`OnionMessage`]: msgs::OnionMessage
720 /// [`MessageRouter`]: crate::onion_message::messenger::MessageRouter
721 /// [`Destination`]: crate::onion_message::messenger::Destination
722 /// [`OnionMessageHandler`]: crate::ln::msgs::OnionMessageHandler
724 /// The node id for the node needing a connection.
726 /// Sockets for connecting to the node.
727 addresses: Vec<msgs::SocketAddress>,
729 /// Indicates a request for an invoice failed to yield a response in a reasonable amount of time
730 /// or was explicitly abandoned by [`ChannelManager::abandon_payment`]. This may be for an
731 /// [`InvoiceRequest`] sent for an [`Offer`] or for a [`Refund`] that hasn't been redeemed.
733 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
734 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
735 /// [`Offer`]: crate::offers::offer::Offer
736 /// [`Refund`]: crate::offers::refund::Refund
737 InvoiceRequestFailed {
738 /// The `payment_id` to have been associated with payment for the requested invoice.
739 payment_id: PaymentId,
741 /// Indicates a [`Bolt12Invoice`] in response to an [`InvoiceRequest`] or a [`Refund`] was
744 /// This event will only be generated if [`UserConfig::manually_handle_bolt12_invoices`] is set.
745 /// Use [`ChannelManager::send_payment_for_bolt12_invoice`] to pay the invoice or
746 /// [`ChannelManager::abandon_payment`] to abandon the associated payment. See those docs for
749 /// [`InvoiceRequest`]: crate::offers::invoice_request::InvoiceRequest
750 /// [`Refund`]: crate::offers::refund::Refund
751 /// [`UserConfig::manually_handle_bolt12_invoices`]: crate::util::config::UserConfig::manually_handle_bolt12_invoices
752 /// [`ChannelManager::send_payment_for_bolt12_invoice`]: crate::ln::channelmanager::ChannelManager::send_payment_for_bolt12_invoice
753 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
755 /// The `payment_id` associated with payment for the invoice.
756 payment_id: PaymentId,
757 /// The invoice to pay.
758 invoice: Bolt12Invoice,
759 /// A responder for replying with an [`InvoiceError`] if needed.
761 /// `None` if the invoice wasn't sent with a reply path.
763 /// [`InvoiceError`]: crate::offers::invoice_error::InvoiceError
764 responder: Option<Responder>,
766 /// Indicates an outbound payment we made succeeded (i.e. it made it all the way to its target
767 /// and we got back the payment preimage for it).
769 /// Note for MPP payments: in rare cases, this event may be preceded by a `PaymentPathFailed`
770 /// event. In this situation, you SHOULD treat this payment as having succeeded.
772 /// The `payment_id` passed to [`ChannelManager::send_payment`].
774 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
775 payment_id: Option<PaymentId>,
776 /// The preimage to the hash given to ChannelManager::send_payment.
777 /// Note that this serves as a payment receipt, if you wish to have such a thing, you must
778 /// store it somehow!
779 payment_preimage: PaymentPreimage,
780 /// The hash that was given to [`ChannelManager::send_payment`].
782 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
783 payment_hash: PaymentHash,
784 /// The total fee which was spent at intermediate hops in this payment, across all paths.
786 /// Note that, like [`Route::get_total_fees`] this does *not* include any potential
787 /// overpayment to the recipient node.
789 /// If the recipient or an intermediate node misbehaves and gives us free money, this may
790 /// overstate the amount paid, though this is unlikely.
792 /// [`Route::get_total_fees`]: crate::routing::router::Route::get_total_fees
793 fee_paid_msat: Option<u64>,
795 /// Indicates an outbound payment failed. Individual [`Event::PaymentPathFailed`] events
796 /// provide failure information for each path attempt in the payment, including retries.
798 /// This event is provided once there are no further pending HTLCs for the payment and the
799 /// payment is no longer retryable, due either to the [`Retry`] provided or
800 /// [`ChannelManager::abandon_payment`] having been called for the corresponding payment.
802 /// In exceedingly rare cases, it is possible that an [`Event::PaymentFailed`] is generated for
803 /// a payment after an [`Event::PaymentSent`] event for this same payment has already been
804 /// received and processed. In this case, the [`Event::PaymentFailed`] event MUST be ignored,
805 /// and the payment MUST be treated as having succeeded.
807 /// [`Retry`]: crate::ln::channelmanager::Retry
808 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
810 /// The `payment_id` passed to [`ChannelManager::send_payment`].
812 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
813 payment_id: PaymentId,
814 /// The hash that was given to [`ChannelManager::send_payment`].
816 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
817 payment_hash: PaymentHash,
818 /// The reason the payment failed. This is only `None` for events generated or serialized
819 /// by versions prior to 0.0.115.
820 reason: Option<PaymentFailureReason>,
822 /// Indicates that a path for an outbound payment was successful.
824 /// Always generated after [`Event::PaymentSent`] and thus useful for scoring channels. See
825 /// [`Event::PaymentSent`] for obtaining the payment preimage.
826 PaymentPathSuccessful {
827 /// The `payment_id` passed to [`ChannelManager::send_payment`].
829 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
830 payment_id: PaymentId,
831 /// The hash that was given to [`ChannelManager::send_payment`].
833 /// This will be `Some` for all payments which completed on LDK 0.0.104 or later.
835 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
836 payment_hash: Option<PaymentHash>,
837 /// The payment path that was successful.
839 /// May contain a closed channel if the HTLC sent along the path was fulfilled on chain.
842 /// Indicates an outbound HTLC we sent failed, likely due to an intermediary node being unable to
845 /// Note that this does *not* indicate that all paths for an MPP payment have failed, see
846 /// [`Event::PaymentFailed`].
848 /// See [`ChannelManager::abandon_payment`] for giving up on this payment before its retries have
851 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
853 /// The `payment_id` passed to [`ChannelManager::send_payment`].
855 /// This will be `Some` for all payment paths which failed on LDK 0.0.103 or later.
857 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
858 /// [`ChannelManager::abandon_payment`]: crate::ln::channelmanager::ChannelManager::abandon_payment
859 payment_id: Option<PaymentId>,
860 /// The hash that was given to [`ChannelManager::send_payment`].
862 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
863 payment_hash: PaymentHash,
864 /// Indicates the payment was rejected for some reason by the recipient. This implies that
865 /// the payment has failed, not just the route in question. If this is not set, the payment may
866 /// be retried via a different route.
867 payment_failed_permanently: bool,
868 /// Extra error details based on the failure type. May contain an update that needs to be
869 /// applied to the [`NetworkGraph`].
871 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
872 failure: PathFailure,
873 /// The payment path that failed.
875 /// The channel responsible for the failed payment path.
877 /// Note that for route hints or for the first hop in a path this may be an SCID alias and
878 /// may not refer to a channel in the public network graph. These aliases may also collide
879 /// with channels in the public network graph.
881 /// If this is `Some`, then the corresponding channel should be avoided when the payment is
882 /// retried. May be `None` for older [`Event`] serializations.
883 short_channel_id: Option<u64>,
885 error_code: Option<u16>,
887 error_data: Option<Vec<u8>>,
889 /// Indicates that a probe payment we sent returned successful, i.e., only failed at the destination.
891 /// The id returned by [`ChannelManager::send_probe`].
893 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
894 payment_id: PaymentId,
895 /// The hash generated by [`ChannelManager::send_probe`].
897 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
898 payment_hash: PaymentHash,
899 /// The payment path that was successful.
902 /// Indicates that a probe payment we sent failed at an intermediary node on the path.
904 /// The id returned by [`ChannelManager::send_probe`].
906 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
907 payment_id: PaymentId,
908 /// The hash generated by [`ChannelManager::send_probe`].
910 /// [`ChannelManager::send_probe`]: crate::ln::channelmanager::ChannelManager::send_probe
911 payment_hash: PaymentHash,
912 /// The payment path that failed.
914 /// The channel responsible for the failed probe.
916 /// Note that for route hints or for the first hop in a path this may be an SCID alias and
917 /// may not refer to a channel in the public network graph. These aliases may also collide
918 /// with channels in the public network graph.
919 short_channel_id: Option<u64>,
921 /// Used to indicate that [`ChannelManager::process_pending_htlc_forwards`] should be called at
922 /// a time in the future.
924 /// [`ChannelManager::process_pending_htlc_forwards`]: crate::ln::channelmanager::ChannelManager::process_pending_htlc_forwards
925 PendingHTLCsForwardable {
926 /// The minimum amount of time that should be waited prior to calling
927 /// process_pending_htlc_forwards. To increase the effort required to correlate payments,
928 /// you should wait a random amount of time in roughly the range (now + time_forwardable,
929 /// now + 5*time_forwardable).
930 time_forwardable: Duration,
932 /// Used to indicate that we've intercepted an HTLC forward. This event will only be generated if
933 /// you've encoded an intercept scid in the receiver's invoice route hints using
934 /// [`ChannelManager::get_intercept_scid`] and have set [`UserConfig::accept_intercept_htlcs`].
936 /// [`ChannelManager::forward_intercepted_htlc`] or
937 /// [`ChannelManager::fail_intercepted_htlc`] MUST be called in response to this event. See
938 /// their docs for more information.
940 /// [`ChannelManager::get_intercept_scid`]: crate::ln::channelmanager::ChannelManager::get_intercept_scid
941 /// [`UserConfig::accept_intercept_htlcs`]: crate::util::config::UserConfig::accept_intercept_htlcs
942 /// [`ChannelManager::forward_intercepted_htlc`]: crate::ln::channelmanager::ChannelManager::forward_intercepted_htlc
943 /// [`ChannelManager::fail_intercepted_htlc`]: crate::ln::channelmanager::ChannelManager::fail_intercepted_htlc
945 /// An id to help LDK identify which HTLC is being forwarded or failed.
946 intercept_id: InterceptId,
947 /// The fake scid that was programmed as the next hop's scid, generated using
948 /// [`ChannelManager::get_intercept_scid`].
950 /// [`ChannelManager::get_intercept_scid`]: crate::ln::channelmanager::ChannelManager::get_intercept_scid
951 requested_next_hop_scid: u64,
952 /// The payment hash used for this HTLC.
953 payment_hash: PaymentHash,
954 /// How many msats were received on the inbound edge of this HTLC.
955 inbound_amount_msat: u64,
956 /// How many msats the payer intended to route to the next node. Depending on the reason you are
957 /// intercepting this payment, you might take a fee by forwarding less than this amount.
958 /// Forwarding less than this amount may break compatibility with LDK versions prior to 0.0.116.
960 /// Note that LDK will NOT check that expected fees were factored into this value. You MUST
961 /// check that whatever fee you want has been included here or subtract it as required. Further,
962 /// LDK will not stop you from forwarding more than you received.
963 expected_outbound_amount_msat: u64,
965 /// Used to indicate that an output which you should know how to spend was confirmed on chain
966 /// and is now spendable.
968 /// Such an output will *never* be spent directly by LDK, and are not at risk of your
969 /// counterparty spending them due to some kind of timeout. Thus, you need to store them
970 /// somewhere and spend them when you create on-chain transactions.
972 /// You may hand them to the [`OutputSweeper`] utility which will store and (re-)generate spending
973 /// transactions for you.
975 /// [`OutputSweeper`]: crate::util::sweep::OutputSweeper
977 /// The outputs which you should store as spendable by you.
978 outputs: Vec<SpendableOutputDescriptor>,
979 /// The `channel_id` indicating which channel the spendable outputs belong to.
981 /// This will always be `Some` for events generated by LDK versions 0.0.117 and above.
982 channel_id: Option<ChannelId>,
984 /// This event is generated when a payment has been successfully forwarded through us and a
985 /// forwarding fee earned.
987 /// The channel id of the incoming channel between the previous node and us.
989 /// This is only `None` for events generated or serialized by versions prior to 0.0.107.
990 prev_channel_id: Option<ChannelId>,
991 /// The channel id of the outgoing channel between the next node and us.
993 /// This is only `None` for events generated or serialized by versions prior to 0.0.107.
994 next_channel_id: Option<ChannelId>,
995 /// The `user_channel_id` of the incoming channel between the previous node and us.
997 /// This is only `None` for events generated or serialized by versions prior to 0.0.122.
998 prev_user_channel_id: Option<u128>,
999 /// The `user_channel_id` of the outgoing channel between the next node and us.
1001 /// This will be `None` if the payment was settled via an on-chain transaction. See the
1002 /// caveat described for the `total_fee_earned_msat` field. Moreover it will be `None` for
1003 /// events generated or serialized by versions prior to 0.0.122.
1004 next_user_channel_id: Option<u128>,
1005 /// The total fee, in milli-satoshis, which was earned as a result of the payment.
1007 /// Note that if we force-closed the channel over which we forwarded an HTLC while the HTLC
1008 /// was pending, the amount the next hop claimed will have been rounded down to the nearest
1009 /// whole satoshi. Thus, the fee calculated here may be higher than expected as we still
1010 /// claimed the full value in millisatoshis from the source. In this case,
1011 /// `claim_from_onchain_tx` will be set.
1013 /// If the channel which sent us the payment has been force-closed, we will claim the funds
1014 /// via an on-chain transaction. In that case we do not yet know the on-chain transaction
1015 /// fees which we will spend and will instead set this to `None`. It is possible duplicate
1016 /// `PaymentForwarded` events are generated for the same payment iff `total_fee_earned_msat` is
1018 total_fee_earned_msat: Option<u64>,
1019 /// The share of the total fee, in milli-satoshis, which was withheld in addition to the
1022 /// This will only be `Some` if we forwarded an intercepted HTLC with less than the
1023 /// expected amount. This means our counterparty accepted to receive less than the invoice
1024 /// amount, e.g., by claiming the payment featuring a corresponding
1025 /// [`PaymentClaimable::counterparty_skimmed_fee_msat`].
1027 /// Will also always be `None` for events serialized with LDK prior to version 0.0.122.
1029 /// The caveat described above the `total_fee_earned_msat` field applies here as well.
1031 /// [`PaymentClaimable::counterparty_skimmed_fee_msat`]: Self::PaymentClaimable::counterparty_skimmed_fee_msat
1032 skimmed_fee_msat: Option<u64>,
1033 /// If this is `true`, the forwarded HTLC was claimed by our counterparty via an on-chain
1035 claim_from_onchain_tx: bool,
1036 /// The final amount forwarded, in milli-satoshis, after the fee is deducted.
1038 /// The caveat described above the `total_fee_earned_msat` field applies here as well.
1039 outbound_amount_forwarded_msat: Option<u64>,
1041 /// Used to indicate that a channel with the given `channel_id` is being opened and pending
1042 /// confirmation on-chain.
1044 /// This event is emitted when the funding transaction has been signed and is broadcast to the
1045 /// network. For 0conf channels it will be immediately followed by the corresponding
1046 /// [`Event::ChannelReady`] event.
1048 /// The `channel_id` of the channel that is pending confirmation.
1049 channel_id: ChannelId,
1050 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`] for outbound
1051 /// channels, or to [`ChannelManager::accept_inbound_channel`] for inbound channels if
1052 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
1053 /// `user_channel_id` will be randomized for an inbound channel.
1055 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
1056 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
1057 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
1058 user_channel_id: u128,
1059 /// The `temporary_channel_id` this channel used to be known by during channel establishment.
1061 /// Will be `None` for channels created prior to LDK version 0.0.115.
1062 former_temporary_channel_id: Option<ChannelId>,
1063 /// The `node_id` of the channel counterparty.
1064 counterparty_node_id: PublicKey,
1065 /// The outpoint of the channel's funding transaction.
1066 funding_txo: OutPoint,
1067 /// The features that this channel will operate with.
1069 /// Will be `None` for channels created prior to LDK version 0.0.122.
1070 channel_type: Option<ChannelTypeFeatures>,
1072 /// Used to indicate that a channel with the given `channel_id` is ready to
1073 /// be used. This event is emitted either when the funding transaction has been confirmed
1074 /// on-chain, or, in case of a 0conf channel, when both parties have confirmed the channel
1077 /// The `channel_id` of the channel that is ready.
1078 channel_id: ChannelId,
1079 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`] for outbound
1080 /// channels, or to [`ChannelManager::accept_inbound_channel`] for inbound channels if
1081 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
1082 /// `user_channel_id` will be randomized for an inbound channel.
1084 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
1085 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
1086 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
1087 user_channel_id: u128,
1088 /// The `node_id` of the channel counterparty.
1089 counterparty_node_id: PublicKey,
1090 /// The features that this channel will operate with.
1091 channel_type: ChannelTypeFeatures,
1093 /// Used to indicate that a channel that got past the initial handshake with the given `channel_id` is in the
1094 /// process of closure. This includes previously opened channels, and channels that time out from not being funded.
1096 /// Note that this event is only triggered for accepted channels: if the
1097 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true and the channel is
1098 /// rejected, no `ChannelClosed` event will be sent.
1100 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
1101 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
1103 /// The `channel_id` of the channel which has been closed. Note that on-chain transactions
1104 /// resolving the channel are likely still awaiting confirmation.
1105 channel_id: ChannelId,
1106 /// The `user_channel_id` value passed in to [`ChannelManager::create_channel`] for outbound
1107 /// channels, or to [`ChannelManager::accept_inbound_channel`] for inbound channels if
1108 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true. Otherwise
1109 /// `user_channel_id` will be randomized for inbound channels.
1110 /// This may be zero for inbound channels serialized prior to 0.0.113 and will always be
1111 /// zero for objects serialized with LDK versions prior to 0.0.102.
1113 /// [`ChannelManager::create_channel`]: crate::ln::channelmanager::ChannelManager::create_channel
1114 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
1115 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
1116 user_channel_id: u128,
1117 /// The reason the channel was closed.
1118 reason: ClosureReason,
1119 /// Counterparty in the closed channel.
1121 /// This field will be `None` for objects serialized prior to LDK 0.0.117.
1122 counterparty_node_id: Option<PublicKey>,
1123 /// Channel capacity of the closing channel (sats).
1125 /// This field will be `None` for objects serialized prior to LDK 0.0.117.
1126 channel_capacity_sats: Option<u64>,
1127 /// The original channel funding TXO; this helps checking for the existence and confirmation
1128 /// status of the closing tx.
1129 /// Note that for instances serialized in v0.0.119 or prior this will be missing (None).
1130 channel_funding_txo: Option<transaction::OutPoint>,
1132 /// Used to indicate to the user that they can abandon the funding transaction and recycle the
1133 /// inputs for another purpose.
1135 /// This event is not guaranteed to be generated for channels that are closed due to a restart.
1137 /// The channel_id of the channel which has been closed.
1138 channel_id: ChannelId,
1139 /// The full transaction received from the user
1140 transaction: Transaction
1142 /// Indicates a request to open a new channel by a peer.
1144 /// To accept the request, call [`ChannelManager::accept_inbound_channel`]. To reject the request,
1145 /// call [`ChannelManager::force_close_without_broadcasting_txn`]. Note that a ['ChannelClosed`]
1146 /// event will _not_ be triggered if the channel is rejected.
1148 /// The event is only triggered when a new open channel request is received and the
1149 /// [`UserConfig::manually_accept_inbound_channels`] config flag is set to true.
1151 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
1152 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
1153 /// [`UserConfig::manually_accept_inbound_channels`]: crate::util::config::UserConfig::manually_accept_inbound_channels
1154 OpenChannelRequest {
1155 /// The temporary channel ID of the channel requested to be opened.
1157 /// When responding to the request, the `temporary_channel_id` should be passed
1158 /// back to the ChannelManager through [`ChannelManager::accept_inbound_channel`] to accept,
1159 /// or through [`ChannelManager::force_close_without_broadcasting_txn`] to reject.
1161 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
1162 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
1163 temporary_channel_id: ChannelId,
1164 /// The node_id of the counterparty requesting to open the channel.
1166 /// When responding to the request, the `counterparty_node_id` should be passed
1167 /// back to the `ChannelManager` through [`ChannelManager::accept_inbound_channel`] to
1168 /// accept the request, or through [`ChannelManager::force_close_without_broadcasting_txn`] to reject the
1171 /// [`ChannelManager::accept_inbound_channel`]: crate::ln::channelmanager::ChannelManager::accept_inbound_channel
1172 /// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn
1173 counterparty_node_id: PublicKey,
1174 /// The channel value of the requested channel.
1175 funding_satoshis: u64,
1176 /// Our starting balance in the channel if the request is accepted, in milli-satoshi.
1178 /// The features that this channel will operate with. If you reject the channel, a
1179 /// well-behaved counterparty may automatically re-attempt the channel with a new set of
1182 /// Note that if [`ChannelTypeFeatures::supports_scid_privacy`] returns true on this type,
1183 /// the resulting [`ChannelManager`] will not be readable by versions of LDK prior to
1186 /// Furthermore, note that if [`ChannelTypeFeatures::supports_zero_conf`] returns true on this type,
1187 /// the resulting [`ChannelManager`] will not be readable by versions of LDK prior to
1188 /// 0.0.107. Channels setting this type also need to get manually accepted via
1189 /// [`crate::ln::channelmanager::ChannelManager::accept_inbound_channel_from_trusted_peer_0conf`],
1190 /// or will be rejected otherwise.
1192 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
1193 channel_type: ChannelTypeFeatures,
1195 /// Indicates that the HTLC was accepted, but could not be processed when or after attempting to
1198 /// Some scenarios where this event may be sent include:
1199 /// * Insufficient capacity in the outbound channel
1200 /// * While waiting to forward the HTLC, the channel it is meant to be forwarded through closes
1201 /// * When an unknown SCID is requested for forwarding a payment.
1202 /// * Expected MPP amount has already been reached
1203 /// * The HTLC has timed out
1205 /// This event, however, does not get generated if an HTLC fails to meet the forwarding
1206 /// requirements (i.e. insufficient fees paid, or a CLTV that is too soon).
1207 HTLCHandlingFailed {
1208 /// The channel over which the HTLC was received.
1209 prev_channel_id: ChannelId,
1210 /// Destination of the HTLC that failed to be processed.
1211 failed_next_destination: HTLCDestination,
1213 /// Indicates that a transaction originating from LDK needs to have its fee bumped. This event
1214 /// requires confirmed external funds to be readily available to spend.
1216 /// LDK does not currently generate this event unless the
1217 /// [`ChannelHandshakeConfig::negotiate_anchors_zero_fee_htlc_tx`] config flag is set to true.
1218 /// It is limited to the scope of channels with anchor outputs.
1220 /// [`ChannelHandshakeConfig::negotiate_anchors_zero_fee_htlc_tx`]: crate::util::config::ChannelHandshakeConfig::negotiate_anchors_zero_fee_htlc_tx
1221 BumpTransaction(BumpTransactionEvent),
1222 /// We received an onion message that is intended to be forwarded to a peer
1223 /// that is currently offline. This event will only be generated if the
1224 /// `OnionMessenger` was initialized with
1225 /// [`OnionMessenger::new_with_offline_peer_interception`], see its docs.
1227 /// [`OnionMessenger::new_with_offline_peer_interception`]: crate::onion_message::messenger::OnionMessenger::new_with_offline_peer_interception
1228 OnionMessageIntercepted {
1229 /// The node id of the offline peer.
1230 peer_node_id: PublicKey,
1231 /// The onion message intended to be forwarded to `peer_node_id`.
1232 message: msgs::OnionMessage,
1234 /// Indicates that an onion message supporting peer has come online and it may
1235 /// be time to forward any onion messages that were previously intercepted for
1236 /// them. This event will only be generated if the `OnionMessenger` was
1237 /// initialized with
1238 /// [`OnionMessenger::new_with_offline_peer_interception`], see its docs.
1240 /// [`OnionMessenger::new_with_offline_peer_interception`]: crate::onion_message::messenger::OnionMessenger::new_with_offline_peer_interception
1241 OnionMessagePeerConnected {
1242 /// The node id of the peer we just connected to, who advertises support for
1244 peer_node_id: PublicKey,
1248 impl Writeable for Event {
1249 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1251 &Event::FundingGenerationReady { .. } => {
1253 // We never write out FundingGenerationReady events as, upon disconnection, peers
1254 // drop any channels which have not yet exchanged funding_signed.
1256 &Event::PaymentClaimable { ref payment_hash, ref amount_msat, counterparty_skimmed_fee_msat,
1257 ref purpose, ref receiver_node_id, ref via_channel_id, ref via_user_channel_id,
1258 ref claim_deadline, ref onion_fields
1261 let mut payment_secret = None;
1262 let payment_preimage;
1263 let mut payment_context = None;
1265 PaymentPurpose::Bolt11InvoicePayment {
1266 payment_preimage: preimage, payment_secret: secret
1268 payment_secret = Some(secret);
1269 payment_preimage = *preimage;
1271 PaymentPurpose::Bolt12OfferPayment {
1272 payment_preimage: preimage, payment_secret: secret, payment_context: context
1274 payment_secret = Some(secret);
1275 payment_preimage = *preimage;
1276 payment_context = Some(PaymentContextRef::Bolt12Offer(context));
1278 PaymentPurpose::Bolt12RefundPayment {
1279 payment_preimage: preimage, payment_secret: secret, payment_context: context
1281 payment_secret = Some(secret);
1282 payment_preimage = *preimage;
1283 payment_context = Some(PaymentContextRef::Bolt12Refund(context));
1285 PaymentPurpose::SpontaneousPayment(preimage) => {
1286 payment_preimage = Some(*preimage);
1289 let skimmed_fee_opt = if counterparty_skimmed_fee_msat == 0 { None }
1290 else { Some(counterparty_skimmed_fee_msat) };
1291 write_tlv_fields!(writer, {
1292 (0, payment_hash, required),
1293 (1, receiver_node_id, option),
1294 (2, payment_secret, option),
1295 (3, via_channel_id, option),
1296 (4, amount_msat, required),
1297 (5, via_user_channel_id, option),
1298 // Type 6 was `user_payment_id` on 0.0.103 and earlier
1299 (7, claim_deadline, option),
1300 (8, payment_preimage, option),
1301 (9, onion_fields, option),
1302 (10, skimmed_fee_opt, option),
1303 (11, payment_context, option),
1306 &Event::PaymentSent { ref payment_id, ref payment_preimage, ref payment_hash, ref fee_paid_msat } => {
1308 write_tlv_fields!(writer, {
1309 (0, payment_preimage, required),
1310 (1, payment_hash, required),
1311 (3, payment_id, option),
1312 (5, fee_paid_msat, option),
1315 &Event::PaymentPathFailed {
1316 ref payment_id, ref payment_hash, ref payment_failed_permanently, ref failure,
1317 ref path, ref short_channel_id,
1325 error_code.write(writer)?;
1327 error_data.write(writer)?;
1328 write_tlv_fields!(writer, {
1329 (0, payment_hash, required),
1330 (1, None::<NetworkUpdate>, option), // network_update in LDK versions prior to 0.0.114
1331 (2, payment_failed_permanently, required),
1332 (3, false, required), // all_paths_failed in LDK versions prior to 0.0.114
1333 (4, path.blinded_tail, option),
1334 (5, path.hops, required_vec),
1335 (7, short_channel_id, option),
1336 (9, None::<RouteParameters>, option), // retry in LDK versions prior to 0.0.115
1337 (11, payment_id, option),
1338 (13, failure, required),
1341 &Event::PendingHTLCsForwardable { time_forwardable: _ } => {
1343 // Note that we now ignore these on the read end as we'll re-generate them in
1344 // ChannelManager, we write them here only for backwards compatibility.
1346 &Event::SpendableOutputs { ref outputs, channel_id } => {
1348 write_tlv_fields!(writer, {
1349 (0, WithoutLength(outputs), required),
1350 (1, channel_id, option),
1353 &Event::HTLCIntercepted { requested_next_hop_scid, payment_hash, inbound_amount_msat, expected_outbound_amount_msat, intercept_id } => {
1355 let intercept_scid = InterceptNextHop::FakeScid { requested_next_hop_scid };
1356 write_tlv_fields!(writer, {
1357 (0, intercept_id, required),
1358 (2, intercept_scid, required),
1359 (4, payment_hash, required),
1360 (6, inbound_amount_msat, required),
1361 (8, expected_outbound_amount_msat, required),
1364 &Event::PaymentForwarded {
1365 prev_channel_id, next_channel_id, prev_user_channel_id, next_user_channel_id,
1366 total_fee_earned_msat, skimmed_fee_msat, claim_from_onchain_tx,
1367 outbound_amount_forwarded_msat,
1370 write_tlv_fields!(writer, {
1371 (0, total_fee_earned_msat, option),
1372 (1, prev_channel_id, option),
1373 (2, claim_from_onchain_tx, required),
1374 (3, next_channel_id, option),
1375 (5, outbound_amount_forwarded_msat, option),
1376 (7, skimmed_fee_msat, option),
1377 (9, prev_user_channel_id, option),
1378 (11, next_user_channel_id, option),
1381 &Event::ChannelClosed { ref channel_id, ref user_channel_id, ref reason,
1382 ref counterparty_node_id, ref channel_capacity_sats, ref channel_funding_txo
1385 // `user_channel_id` used to be a single u64 value. In order to remain backwards
1386 // compatible with versions prior to 0.0.113, the u128 is serialized as two
1387 // separate u64 values.
1388 let user_channel_id_low = *user_channel_id as u64;
1389 let user_channel_id_high = (*user_channel_id >> 64) as u64;
1390 write_tlv_fields!(writer, {
1391 (0, channel_id, required),
1392 (1, user_channel_id_low, required),
1393 (2, reason, required),
1394 (3, user_channel_id_high, required),
1395 (5, counterparty_node_id, option),
1396 (7, channel_capacity_sats, option),
1397 (9, channel_funding_txo, option),
1400 &Event::DiscardFunding { ref channel_id, ref transaction } => {
1401 11u8.write(writer)?;
1402 write_tlv_fields!(writer, {
1403 (0, channel_id, required),
1404 (2, transaction, required)
1407 &Event::PaymentPathSuccessful { ref payment_id, ref payment_hash, ref path } => {
1408 13u8.write(writer)?;
1409 write_tlv_fields!(writer, {
1410 (0, payment_id, required),
1411 (2, payment_hash, option),
1412 (4, path.hops, required_vec),
1413 (6, path.blinded_tail, option),
1416 &Event::PaymentFailed { ref payment_id, ref payment_hash, ref reason } => {
1417 15u8.write(writer)?;
1418 write_tlv_fields!(writer, {
1419 (0, payment_id, required),
1420 (1, reason, option),
1421 (2, payment_hash, required),
1424 &Event::OpenChannelRequest { .. } => {
1425 17u8.write(writer)?;
1426 // We never write the OpenChannelRequest events as, upon disconnection, peers
1427 // drop any channels which have not yet exchanged funding_signed.
1429 &Event::PaymentClaimed { ref payment_hash, ref amount_msat, ref purpose, ref receiver_node_id, ref htlcs, ref sender_intended_total_msat, ref onion_fields } => {
1430 19u8.write(writer)?;
1431 write_tlv_fields!(writer, {
1432 (0, payment_hash, required),
1433 (1, receiver_node_id, option),
1434 (2, purpose, required),
1435 (4, amount_msat, required),
1436 (5, *htlcs, optional_vec),
1437 (7, sender_intended_total_msat, option),
1438 (9, onion_fields, option),
1441 &Event::ProbeSuccessful { ref payment_id, ref payment_hash, ref path } => {
1442 21u8.write(writer)?;
1443 write_tlv_fields!(writer, {
1444 (0, payment_id, required),
1445 (2, payment_hash, required),
1446 (4, path.hops, required_vec),
1447 (6, path.blinded_tail, option),
1450 &Event::ProbeFailed { ref payment_id, ref payment_hash, ref path, ref short_channel_id } => {
1451 23u8.write(writer)?;
1452 write_tlv_fields!(writer, {
1453 (0, payment_id, required),
1454 (2, payment_hash, required),
1455 (4, path.hops, required_vec),
1456 (6, short_channel_id, option),
1457 (8, path.blinded_tail, option),
1460 &Event::HTLCHandlingFailed { ref prev_channel_id, ref failed_next_destination } => {
1461 25u8.write(writer)?;
1462 write_tlv_fields!(writer, {
1463 (0, prev_channel_id, required),
1464 (2, failed_next_destination, required),
1467 &Event::BumpTransaction(ref event)=> {
1468 27u8.write(writer)?;
1470 // We never write the ChannelClose|HTLCResolution events as they'll be replayed
1471 // upon restarting anyway if they remain unresolved.
1472 BumpTransactionEvent::ChannelClose { .. } => {}
1473 BumpTransactionEvent::HTLCResolution { .. } => {}
1475 write_tlv_fields!(writer, {}); // Write a length field for forwards compat
1477 &Event::ChannelReady { ref channel_id, ref user_channel_id, ref counterparty_node_id, ref channel_type } => {
1478 29u8.write(writer)?;
1479 write_tlv_fields!(writer, {
1480 (0, channel_id, required),
1481 (2, user_channel_id, required),
1482 (4, counterparty_node_id, required),
1483 (6, channel_type, required),
1486 &Event::ChannelPending { ref channel_id, ref user_channel_id,
1487 ref former_temporary_channel_id, ref counterparty_node_id, ref funding_txo,
1490 31u8.write(writer)?;
1491 write_tlv_fields!(writer, {
1492 (0, channel_id, required),
1493 (1, channel_type, option),
1494 (2, user_channel_id, required),
1495 (4, former_temporary_channel_id, required),
1496 (6, counterparty_node_id, required),
1497 (8, funding_txo, required),
1500 &Event::InvoiceRequestFailed { ref payment_id } => {
1501 33u8.write(writer)?;
1502 write_tlv_fields!(writer, {
1503 (0, payment_id, required),
1506 &Event::ConnectionNeeded { .. } => {
1507 35u8.write(writer)?;
1508 // Never write ConnectionNeeded events as buffered onion messages aren't serialized.
1510 &Event::OnionMessageIntercepted { ref peer_node_id, ref message } => {
1511 37u8.write(writer)?;
1512 write_tlv_fields!(writer, {
1513 (0, peer_node_id, required),
1514 (2, message, required),
1517 &Event::OnionMessagePeerConnected { ref peer_node_id } => {
1518 39u8.write(writer)?;
1519 write_tlv_fields!(writer, {
1520 (0, peer_node_id, required),
1523 &Event::InvoiceReceived { ref payment_id, ref invoice, ref responder } => {
1524 41u8.write(writer)?;
1525 write_tlv_fields!(writer, {
1526 (0, payment_id, required),
1527 (2, invoice, required),
1528 (4, responder, option),
1531 // Note that, going forward, all new events must only write data inside of
1532 // `write_tlv_fields`. Versions 0.0.101+ will ignore odd-numbered events that write
1533 // data via `write_tlv_fields`.
1538 impl MaybeReadable for Event {
1539 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, msgs::DecodeError> {
1540 match Readable::read(reader)? {
1541 // Note that we do not write a length-prefixed TLV for FundingGenerationReady events.
1545 let mut payment_hash = PaymentHash([0; 32]);
1546 let mut payment_preimage = None;
1547 let mut payment_secret = None;
1548 let mut amount_msat = 0;
1549 let mut counterparty_skimmed_fee_msat_opt = None;
1550 let mut receiver_node_id = None;
1551 let mut _user_payment_id = None::<u64>; // Used in 0.0.103 and earlier, no longer written in 0.0.116+.
1552 let mut via_channel_id = None;
1553 let mut claim_deadline = None;
1554 let mut via_user_channel_id = None;
1555 let mut onion_fields = None;
1556 let mut payment_context = None;
1557 read_tlv_fields!(reader, {
1558 (0, payment_hash, required),
1559 (1, receiver_node_id, option),
1560 (2, payment_secret, option),
1561 (3, via_channel_id, option),
1562 (4, amount_msat, required),
1563 (5, via_user_channel_id, option),
1564 (6, _user_payment_id, option),
1565 (7, claim_deadline, option),
1566 (8, payment_preimage, option),
1567 (9, onion_fields, option),
1568 (10, counterparty_skimmed_fee_msat_opt, option),
1569 (11, payment_context, option),
1571 let purpose = match payment_secret {
1572 Some(secret) => PaymentPurpose::from_parts(payment_preimage, secret, payment_context),
1573 None if payment_preimage.is_some() => PaymentPurpose::SpontaneousPayment(payment_preimage.unwrap()),
1574 None => return Err(msgs::DecodeError::InvalidValue),
1576 Ok(Some(Event::PaymentClaimable {
1580 counterparty_skimmed_fee_msat: counterparty_skimmed_fee_msat_opt.unwrap_or(0),
1583 via_user_channel_id,
1592 let mut payment_preimage = PaymentPreimage([0; 32]);
1593 let mut payment_hash = None;
1594 let mut payment_id = None;
1595 let mut fee_paid_msat = None;
1596 read_tlv_fields!(reader, {
1597 (0, payment_preimage, required),
1598 (1, payment_hash, option),
1599 (3, payment_id, option),
1600 (5, fee_paid_msat, option),
1602 if payment_hash.is_none() {
1603 payment_hash = Some(PaymentHash(Sha256::hash(&payment_preimage.0[..]).to_byte_array()));
1605 Ok(Some(Event::PaymentSent {
1608 payment_hash: payment_hash.unwrap(),
1617 let error_code = Readable::read(reader)?;
1619 let error_data = Readable::read(reader)?;
1620 let mut payment_hash = PaymentHash([0; 32]);
1621 let mut payment_failed_permanently = false;
1622 let mut network_update = None;
1623 let mut blinded_tail: Option<BlindedTail> = None;
1624 let mut path: Option<Vec<RouteHop>> = Some(vec![]);
1625 let mut short_channel_id = None;
1626 let mut payment_id = None;
1627 let mut failure_opt = None;
1628 read_tlv_fields!(reader, {
1629 (0, payment_hash, required),
1630 (1, network_update, upgradable_option),
1631 (2, payment_failed_permanently, required),
1632 (4, blinded_tail, option),
1633 // Added as a part of LDK 0.0.101 and always filled in since.
1634 // Defaults to an empty Vec, though likely should have been `Option`al.
1635 (5, path, optional_vec),
1636 (7, short_channel_id, option),
1637 (11, payment_id, option),
1638 (13, failure_opt, upgradable_option),
1640 let failure = failure_opt.unwrap_or_else(|| PathFailure::OnPath { network_update });
1641 Ok(Some(Event::PaymentPathFailed {
1644 payment_failed_permanently,
1646 path: Path { hops: path.unwrap(), blinded_tail },
1659 let mut outputs = WithoutLength(Vec::new());
1660 let mut channel_id: Option<ChannelId> = None;
1661 read_tlv_fields!(reader, {
1662 (0, outputs, required),
1663 (1, channel_id, option),
1665 Ok(Some(Event::SpendableOutputs { outputs: outputs.0, channel_id }))
1670 let mut payment_hash = PaymentHash([0; 32]);
1671 let mut intercept_id = InterceptId([0; 32]);
1672 let mut requested_next_hop_scid = InterceptNextHop::FakeScid { requested_next_hop_scid: 0 };
1673 let mut inbound_amount_msat = 0;
1674 let mut expected_outbound_amount_msat = 0;
1675 read_tlv_fields!(reader, {
1676 (0, intercept_id, required),
1677 (2, requested_next_hop_scid, required),
1678 (4, payment_hash, required),
1679 (6, inbound_amount_msat, required),
1680 (8, expected_outbound_amount_msat, required),
1682 let next_scid = match requested_next_hop_scid {
1683 InterceptNextHop::FakeScid { requested_next_hop_scid: scid } => scid
1685 Ok(Some(Event::HTLCIntercepted {
1687 requested_next_hop_scid: next_scid,
1688 inbound_amount_msat,
1689 expected_outbound_amount_msat,
1695 let mut prev_channel_id = None;
1696 let mut next_channel_id = None;
1697 let mut prev_user_channel_id = None;
1698 let mut next_user_channel_id = None;
1699 let mut total_fee_earned_msat = None;
1700 let mut skimmed_fee_msat = None;
1701 let mut claim_from_onchain_tx = false;
1702 let mut outbound_amount_forwarded_msat = None;
1703 read_tlv_fields!(reader, {
1704 (0, total_fee_earned_msat, option),
1705 (1, prev_channel_id, option),
1706 (2, claim_from_onchain_tx, required),
1707 (3, next_channel_id, option),
1708 (5, outbound_amount_forwarded_msat, option),
1709 (7, skimmed_fee_msat, option),
1710 (9, prev_user_channel_id, option),
1711 (11, next_user_channel_id, option),
1713 Ok(Some(Event::PaymentForwarded {
1714 prev_channel_id, next_channel_id, prev_user_channel_id,
1715 next_user_channel_id, total_fee_earned_msat, skimmed_fee_msat,
1716 claim_from_onchain_tx, outbound_amount_forwarded_msat,
1723 let mut channel_id = ChannelId::new_zero();
1724 let mut reason = UpgradableRequired(None);
1725 let mut user_channel_id_low_opt: Option<u64> = None;
1726 let mut user_channel_id_high_opt: Option<u64> = None;
1727 let mut counterparty_node_id = None;
1728 let mut channel_capacity_sats = None;
1729 let mut channel_funding_txo = None;
1730 read_tlv_fields!(reader, {
1731 (0, channel_id, required),
1732 (1, user_channel_id_low_opt, option),
1733 (2, reason, upgradable_required),
1734 (3, user_channel_id_high_opt, option),
1735 (5, counterparty_node_id, option),
1736 (7, channel_capacity_sats, option),
1737 (9, channel_funding_txo, option),
1740 // `user_channel_id` used to be a single u64 value. In order to remain
1741 // backwards compatible with versions prior to 0.0.113, the u128 is serialized
1742 // as two separate u64 values.
1743 let user_channel_id = (user_channel_id_low_opt.unwrap_or(0) as u128) +
1744 ((user_channel_id_high_opt.unwrap_or(0) as u128) << 64);
1746 Ok(Some(Event::ChannelClosed { channel_id, user_channel_id, reason: _init_tlv_based_struct_field!(reason, upgradable_required),
1747 counterparty_node_id, channel_capacity_sats, channel_funding_txo }))
1753 let mut channel_id = ChannelId::new_zero();
1754 let mut transaction = Transaction{ version: Version::TWO, lock_time: LockTime::ZERO, input: Vec::new(), output: Vec::new() };
1755 read_tlv_fields!(reader, {
1756 (0, channel_id, required),
1757 (2, transaction, required),
1759 Ok(Some(Event::DiscardFunding { channel_id, transaction } ))
1765 _init_and_read_len_prefixed_tlv_fields!(reader, {
1766 (0, payment_id, required),
1767 (2, payment_hash, option),
1768 (4, path, required_vec),
1769 (6, blinded_tail, option),
1771 Ok(Some(Event::PaymentPathSuccessful {
1772 payment_id: payment_id.0.unwrap(),
1774 path: Path { hops: path, blinded_tail },
1781 let mut payment_hash = PaymentHash([0; 32]);
1782 let mut payment_id = PaymentId([0; 32]);
1783 let mut reason = None;
1784 read_tlv_fields!(reader, {
1785 (0, payment_id, required),
1786 (1, reason, upgradable_option),
1787 (2, payment_hash, required),
1789 Ok(Some(Event::PaymentFailed {
1798 // Value 17 is used for `Event::OpenChannelRequest`.
1803 let mut payment_hash = PaymentHash([0; 32]);
1804 let mut purpose = UpgradableRequired(None);
1805 let mut amount_msat = 0;
1806 let mut receiver_node_id = None;
1807 let mut htlcs: Option<Vec<ClaimedHTLC>> = Some(vec![]);
1808 let mut sender_intended_total_msat: Option<u64> = None;
1809 let mut onion_fields = None;
1810 read_tlv_fields!(reader, {
1811 (0, payment_hash, required),
1812 (1, receiver_node_id, option),
1813 (2, purpose, upgradable_required),
1814 (4, amount_msat, required),
1815 (5, htlcs, optional_vec),
1816 (7, sender_intended_total_msat, option),
1817 (9, onion_fields, option),
1819 Ok(Some(Event::PaymentClaimed {
1822 purpose: _init_tlv_based_struct_field!(purpose, upgradable_required),
1824 htlcs: htlcs.unwrap_or(vec![]),
1825 sender_intended_total_msat,
1833 _init_and_read_len_prefixed_tlv_fields!(reader, {
1834 (0, payment_id, required),
1835 (2, payment_hash, required),
1836 (4, path, required_vec),
1837 (6, blinded_tail, option),
1839 Ok(Some(Event::ProbeSuccessful {
1840 payment_id: payment_id.0.unwrap(),
1841 payment_hash: payment_hash.0.unwrap(),
1842 path: Path { hops: path, blinded_tail },
1849 _init_and_read_len_prefixed_tlv_fields!(reader, {
1850 (0, payment_id, required),
1851 (2, payment_hash, required),
1852 (4, path, required_vec),
1853 (6, short_channel_id, option),
1854 (8, blinded_tail, option),
1856 Ok(Some(Event::ProbeFailed {
1857 payment_id: payment_id.0.unwrap(),
1858 payment_hash: payment_hash.0.unwrap(),
1859 path: Path { hops: path, blinded_tail },
1867 let mut prev_channel_id = ChannelId::new_zero();
1868 let mut failed_next_destination_opt = UpgradableRequired(None);
1869 read_tlv_fields!(reader, {
1870 (0, prev_channel_id, required),
1871 (2, failed_next_destination_opt, upgradable_required),
1873 Ok(Some(Event::HTLCHandlingFailed {
1875 failed_next_destination: _init_tlv_based_struct_field!(failed_next_destination_opt, upgradable_required),
1883 let mut channel_id = ChannelId::new_zero();
1884 let mut user_channel_id: u128 = 0;
1885 let mut counterparty_node_id = RequiredWrapper(None);
1886 let mut channel_type = RequiredWrapper(None);
1887 read_tlv_fields!(reader, {
1888 (0, channel_id, required),
1889 (2, user_channel_id, required),
1890 (4, counterparty_node_id, required),
1891 (6, channel_type, required),
1894 Ok(Some(Event::ChannelReady {
1897 counterparty_node_id: counterparty_node_id.0.unwrap(),
1898 channel_type: channel_type.0.unwrap()
1905 let mut channel_id = ChannelId::new_zero();
1906 let mut user_channel_id: u128 = 0;
1907 let mut former_temporary_channel_id = None;
1908 let mut counterparty_node_id = RequiredWrapper(None);
1909 let mut funding_txo = RequiredWrapper(None);
1910 let mut channel_type = None;
1911 read_tlv_fields!(reader, {
1912 (0, channel_id, required),
1913 (1, channel_type, option),
1914 (2, user_channel_id, required),
1915 (4, former_temporary_channel_id, required),
1916 (6, counterparty_node_id, required),
1917 (8, funding_txo, required),
1920 Ok(Some(Event::ChannelPending {
1923 former_temporary_channel_id,
1924 counterparty_node_id: counterparty_node_id.0.unwrap(),
1925 funding_txo: funding_txo.0.unwrap(),
1933 _init_and_read_len_prefixed_tlv_fields!(reader, {
1934 (0, payment_id, required),
1936 Ok(Some(Event::InvoiceRequestFailed {
1937 payment_id: payment_id.0.unwrap(),
1942 // Note that we do not write a length-prefixed TLV for ConnectionNeeded events.
1946 _init_and_read_len_prefixed_tlv_fields!(reader, {
1947 (0, peer_node_id, required),
1948 (2, message, required),
1950 Ok(Some(Event::OnionMessageIntercepted {
1951 peer_node_id: peer_node_id.0.unwrap(), message: message.0.unwrap()
1958 _init_and_read_len_prefixed_tlv_fields!(reader, {
1959 (0, peer_node_id, required),
1961 Ok(Some(Event::OnionMessagePeerConnected {
1962 peer_node_id: peer_node_id.0.unwrap()
1969 _init_and_read_len_prefixed_tlv_fields!(reader, {
1970 (0, payment_id, required),
1971 (2, invoice, required),
1972 (4, responder, option),
1974 Ok(Some(Event::InvoiceReceived {
1975 payment_id: payment_id.0.unwrap(),
1976 invoice: invoice.0.unwrap(),
1982 // Versions prior to 0.0.100 did not ignore odd types, instead returning InvalidValue.
1983 // Version 0.0.100 failed to properly ignore odd types, possibly resulting in corrupt
1985 x if x % 2 == 1 => {
1986 // If the event is of unknown type, assume it was written with `write_tlv_fields`,
1987 // which prefixes the whole thing with a length BigSize. Because the event is
1988 // odd-type unknown, we should treat it as `Ok(None)` even if it has some TLV
1989 // fields that are even. Thus, we avoid using `read_tlv_fields` and simply read
1990 // exactly the number of bytes specified, ignoring them entirely.
1991 let tlv_len: BigSize = Readable::read(reader)?;
1992 FixedLengthReader::new(reader, tlv_len.0)
1993 .eat_remaining().map_err(|_| msgs::DecodeError::ShortRead)?;
1996 _ => Err(msgs::DecodeError::InvalidValue)
2001 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
2002 /// broadcast to most peers).
2003 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
2004 #[derive(Clone, Debug)]
2005 #[cfg_attr(test, derive(PartialEq))]
2006 pub enum MessageSendEvent {
2007 /// Used to indicate that we've accepted a channel open and should send the accept_channel
2008 /// message provided to the given peer.
2010 /// The node_id of the node which should receive this message
2012 /// The message which should be sent.
2013 msg: msgs::AcceptChannel,
2015 /// Used to indicate that we've accepted a V2 channel open and should send the accept_channel2
2016 /// message provided to the given peer.
2017 SendAcceptChannelV2 {
2018 /// The node_id of the node which should receive this message
2020 /// The message which should be sent.
2021 msg: msgs::AcceptChannelV2,
2023 /// Used to indicate that we've initiated a channel open and should send the open_channel
2024 /// message provided to the given peer.
2026 /// The node_id of the node which should receive this message
2028 /// The message which should be sent.
2029 msg: msgs::OpenChannel,
2031 /// Used to indicate that we've initiated a V2 channel open and should send the open_channel2
2032 /// message provided to the given peer.
2034 /// The node_id of the node which should receive this message
2036 /// The message which should be sent.
2037 msg: msgs::OpenChannelV2,
2039 /// Used to indicate that a funding_created message should be sent to the peer with the given node_id.
2040 SendFundingCreated {
2041 /// The node_id of the node which should receive this message
2043 /// The message which should be sent.
2044 msg: msgs::FundingCreated,
2046 /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
2048 /// The node_id of the node which should receive this message
2050 /// The message which should be sent.
2051 msg: msgs::FundingSigned,
2053 /// Used to indicate that a stfu message should be sent to the peer with the given node id.
2055 /// The node_id of the node which should receive this message
2057 /// The message which should be sent.
2060 /// Used to indicate that a splice_init message should be sent to the peer with the given node id.
2062 /// The node_id of the node which should receive this message
2064 /// The message which should be sent.
2065 msg: msgs::SpliceInit,
2067 /// Used to indicate that a splice_ack message should be sent to the peer with the given node id.
2069 /// The node_id of the node which should receive this message
2071 /// The message which should be sent.
2072 msg: msgs::SpliceAck,
2074 /// Used to indicate that a splice_locked message should be sent to the peer with the given node id.
2076 /// The node_id of the node which should receive this message
2078 /// The message which should be sent.
2079 msg: msgs::SpliceLocked,
2081 /// Used to indicate that a tx_add_input message should be sent to the peer with the given node_id.
2083 /// The node_id of the node which should receive this message
2085 /// The message which should be sent.
2086 msg: msgs::TxAddInput,
2088 /// Used to indicate that a tx_add_output message should be sent to the peer with the given node_id.
2090 /// The node_id of the node which should receive this message
2092 /// The message which should be sent.
2093 msg: msgs::TxAddOutput,
2095 /// Used to indicate that a tx_remove_input message should be sent to the peer with the given node_id.
2097 /// The node_id of the node which should receive this message
2099 /// The message which should be sent.
2100 msg: msgs::TxRemoveInput,
2102 /// Used to indicate that a tx_remove_output message should be sent to the peer with the given node_id.
2103 SendTxRemoveOutput {
2104 /// The node_id of the node which should receive this message
2106 /// The message which should be sent.
2107 msg: msgs::TxRemoveOutput,
2109 /// Used to indicate that a tx_complete message should be sent to the peer with the given node_id.
2111 /// The node_id of the node which should receive this message
2113 /// The message which should be sent.
2114 msg: msgs::TxComplete,
2116 /// Used to indicate that a tx_signatures message should be sent to the peer with the given node_id.
2118 /// The node_id of the node which should receive this message
2120 /// The message which should be sent.
2121 msg: msgs::TxSignatures,
2123 /// Used to indicate that a tx_init_rbf message should be sent to the peer with the given node_id.
2125 /// The node_id of the node which should receive this message
2127 /// The message which should be sent.
2128 msg: msgs::TxInitRbf,
2130 /// Used to indicate that a tx_ack_rbf message should be sent to the peer with the given node_id.
2132 /// The node_id of the node which should receive this message
2134 /// The message which should be sent.
2135 msg: msgs::TxAckRbf,
2137 /// Used to indicate that a tx_abort message should be sent to the peer with the given node_id.
2139 /// The node_id of the node which should receive this message
2141 /// The message which should be sent.
2144 /// Used to indicate that a channel_ready message should be sent to the peer with the given node_id.
2146 /// The node_id of the node which should receive these message(s)
2148 /// The channel_ready message which should be sent.
2149 msg: msgs::ChannelReady,
2151 /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
2152 SendAnnouncementSignatures {
2153 /// The node_id of the node which should receive these message(s)
2155 /// The announcement_signatures message which should be sent.
2156 msg: msgs::AnnouncementSignatures,
2158 /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
2159 /// message should be sent to the peer with the given node_id.
2161 /// The node_id of the node which should receive these message(s)
2163 /// The update messages which should be sent. ALL messages in the struct should be sent!
2164 updates: msgs::CommitmentUpdate,
2166 /// Used to indicate that a revoke_and_ack message should be sent to the peer with the given node_id.
2168 /// The node_id of the node which should receive this message
2170 /// The message which should be sent.
2171 msg: msgs::RevokeAndACK,
2173 /// Used to indicate that a closing_signed message should be sent to the peer with the given node_id.
2175 /// The node_id of the node which should receive this message
2177 /// The message which should be sent.
2178 msg: msgs::ClosingSigned,
2180 /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
2182 /// The node_id of the node which should receive this message
2184 /// The message which should be sent.
2185 msg: msgs::Shutdown,
2187 /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
2188 SendChannelReestablish {
2189 /// The node_id of the node which should receive this message
2191 /// The message which should be sent.
2192 msg: msgs::ChannelReestablish,
2194 /// Used to send a channel_announcement and channel_update to a specific peer, likely on
2195 /// initial connection to ensure our peers know about our channels.
2196 SendChannelAnnouncement {
2197 /// The node_id of the node which should receive this message
2199 /// The channel_announcement which should be sent.
2200 msg: msgs::ChannelAnnouncement,
2201 /// The followup channel_update which should be sent.
2202 update_msg: msgs::ChannelUpdate,
2204 /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
2205 /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
2207 /// Note that after doing so, you very likely (unless you did so very recently) want to
2208 /// broadcast a node_announcement (e.g. via [`PeerManager::broadcast_node_announcement`]). This
2209 /// ensures that any nodes which see our channel_announcement also have a relevant
2210 /// node_announcement, including relevant feature flags which may be important for routing
2211 /// through or to us.
2213 /// [`PeerManager::broadcast_node_announcement`]: crate::ln::peer_handler::PeerManager::broadcast_node_announcement
2214 BroadcastChannelAnnouncement {
2215 /// The channel_announcement which should be sent.
2216 msg: msgs::ChannelAnnouncement,
2217 /// The followup channel_update which should be sent.
2218 update_msg: Option<msgs::ChannelUpdate>,
2220 /// Used to indicate that a channel_update should be broadcast to all peers.
2221 BroadcastChannelUpdate {
2222 /// The channel_update which should be sent.
2223 msg: msgs::ChannelUpdate,
2225 /// Used to indicate that a node_announcement should be broadcast to all peers.
2226 BroadcastNodeAnnouncement {
2227 /// The node_announcement which should be sent.
2228 msg: msgs::NodeAnnouncement,
2230 /// Used to indicate that a channel_update should be sent to a single peer.
2231 /// In contrast to [`Self::BroadcastChannelUpdate`], this is used when the channel is a
2232 /// private channel and we shouldn't be informing all of our peers of channel parameters.
2234 /// The node_id of the node which should receive this message
2236 /// The channel_update which should be sent.
2237 msg: msgs::ChannelUpdate,
2239 /// Broadcast an error downstream to be handled
2241 /// The node_id of the node which should receive this message
2243 /// The action which should be taken.
2244 action: msgs::ErrorAction
2246 /// Query a peer for channels with funding transaction UTXOs in a block range.
2247 SendChannelRangeQuery {
2248 /// The node_id of this message recipient
2250 /// The query_channel_range which should be sent.
2251 msg: msgs::QueryChannelRange,
2253 /// Request routing gossip messages from a peer for a list of channels identified by
2254 /// their short_channel_ids.
2256 /// The node_id of this message recipient
2258 /// The query_short_channel_ids which should be sent.
2259 msg: msgs::QueryShortChannelIds,
2261 /// Sends a reply to a channel range query. This may be one of several SendReplyChannelRange events
2262 /// emitted during processing of the query.
2263 SendReplyChannelRange {
2264 /// The node_id of this message recipient
2266 /// The reply_channel_range which should be sent.
2267 msg: msgs::ReplyChannelRange,
2269 /// Sends a timestamp filter for inbound gossip. This should be sent on each new connection to
2270 /// enable receiving gossip messages from the peer.
2271 SendGossipTimestampFilter {
2272 /// The node_id of this message recipient
2274 /// The gossip_timestamp_filter which should be sent.
2275 msg: msgs::GossipTimestampFilter,
2279 /// A trait indicating an object may generate message send events
2280 pub trait MessageSendEventsProvider {
2281 /// Gets the list of pending events which were generated by previous actions, clearing the list
2283 fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent>;
2286 /// A trait indicating an object may generate events.
2288 /// Events are processed by passing an [`EventHandler`] to [`process_pending_events`].
2290 /// Implementations of this trait may also feature an async version of event handling, as shown with
2291 /// [`ChannelManager::process_pending_events_async`] and
2292 /// [`ChainMonitor::process_pending_events_async`].
2296 /// When using this trait, [`process_pending_events`] will call [`handle_event`] for each pending
2297 /// event since the last invocation.
2299 /// In order to ensure no [`Event`]s are lost, implementors of this trait will persist [`Event`]s
2300 /// and replay any unhandled events on startup. An [`Event`] is considered handled when
2301 /// [`process_pending_events`] returns, thus handlers MUST fully handle [`Event`]s and persist any
2302 /// relevant changes to disk *before* returning.
2304 /// Further, because an application may crash between an [`Event`] being handled and the
2305 /// implementor of this trait being re-serialized, [`Event`] handling must be idempotent - in
2306 /// effect, [`Event`]s may be replayed.
2308 /// Note, handlers may call back into the provider and thus deadlocking must be avoided. Be sure to
2309 /// consult the provider's documentation on the implication of processing events and how a handler
2310 /// may safely use the provider (e.g., see [`ChannelManager::process_pending_events`] and
2311 /// [`ChainMonitor::process_pending_events`]).
2313 /// (C-not implementable) As there is likely no reason for a user to implement this trait on their
2316 /// [`process_pending_events`]: Self::process_pending_events
2317 /// [`handle_event`]: EventHandler::handle_event
2318 /// [`ChannelManager::process_pending_events`]: crate::ln::channelmanager::ChannelManager#method.process_pending_events
2319 /// [`ChainMonitor::process_pending_events`]: crate::chain::chainmonitor::ChainMonitor#method.process_pending_events
2320 /// [`ChannelManager::process_pending_events_async`]: crate::ln::channelmanager::ChannelManager::process_pending_events_async
2321 /// [`ChainMonitor::process_pending_events_async`]: crate::chain::chainmonitor::ChainMonitor::process_pending_events_async
2322 pub trait EventsProvider {
2323 /// Processes any events generated since the last call using the given event handler.
2325 /// See the trait-level documentation for requirements.
2326 fn process_pending_events<H: Deref>(&self, handler: H) where H::Target: EventHandler;
2329 /// A trait implemented for objects handling events from [`EventsProvider`].
2331 /// An async variation also exists for implementations of [`EventsProvider`] that support async
2332 /// event handling. The async event handler should satisfy the generic bounds: `F:
2333 /// core::future::Future, H: Fn(Event) -> F`.
2334 pub trait EventHandler {
2335 /// Handles the given [`Event`].
2337 /// See [`EventsProvider`] for details that must be considered when implementing this method.
2338 fn handle_event(&self, event: Event);
2341 impl<F> EventHandler for F where F: Fn(Event) {
2342 fn handle_event(&self, event: Event) {
2347 impl<T: EventHandler> EventHandler for Arc<T> {
2348 fn handle_event(&self, event: Event) {
2349 self.deref().handle_event(event)