1 //! Events are returned from various bits in the library which indicate some action must be taken
4 //! Because we don't have a built-in runtime, it's up to the client to call events at a time in the
5 //! future, as well as generate and broadcast funding transactions handle payment preimages and a
9 use ln::channelmanager::{PaymentPreimage, PaymentHash};
10 use chain::transaction::OutPoint;
11 use chain::keysinterface::SpendableOutputDescriptor;
12 use util::ser::{Writeable, Writer, MaybeReadable, Readable};
14 use bitcoin::blockdata::script::Script;
16 use secp256k1::key::PublicKey;
18 use std::time::Duration;
20 /// An Event which you should probably take some action in response to.
22 /// Note that while Writeable and Readable are implemented for Event, you probably shouldn't use
23 /// them directly as they don't round-trip exactly (for example FundingGenerationReady is never
24 /// written as it makes no sense to respond to it after reconnecting to peers).
26 /// Used to indicate that the client should generate a funding transaction with the given
27 /// parameters and then call ChannelManager::funding_transaction_generated.
28 /// Generated in ChannelManager message handling.
29 /// Note that *all inputs* in the funding transaction must spend SegWit outputs or your
30 /// counterparty can steal your funds!
31 FundingGenerationReady {
32 /// The random channel_id we picked which you'll need to pass into
33 /// ChannelManager::funding_transaction_generated.
34 temporary_channel_id: [u8; 32],
35 /// The value, in satoshis, that the output should have.
36 channel_value_satoshis: u64,
37 /// The script which should be used in the transaction output.
38 output_script: Script,
39 /// The value passed in to ChannelManager::create_channel
42 /// Used to indicate that the client may now broadcast the funding transaction it created for a
43 /// channel. Broadcasting such a transaction prior to this event may lead to our counterparty
44 /// trivially stealing all funds in the funding transaction!
45 FundingBroadcastSafe {
46 /// The output, which was passed to ChannelManager::funding_transaction_generated, which is
47 /// now safe to broadcast.
48 funding_txo: OutPoint,
49 /// The value passed in to ChannelManager::create_channel
52 /// Indicates we've received money! Just gotta dig out that payment preimage and feed it to
53 /// ChannelManager::claim_funds to get it....
54 /// Note that if the preimage is not known or the amount paid is incorrect, you must call
55 /// ChannelManager::fail_htlc_backwards to free up resources for this HTLC.
56 /// The amount paid should be considered 'incorrect' when it is less than or more than twice
57 /// the amount expected.
59 /// The hash for which the preimage should be handed to the ChannelManager.
60 payment_hash: PaymentHash,
61 /// The value, in thousandths of a satoshi, that this payment is for. Note that you must
62 /// compare this to the expected value before accepting the payment (as otherwise you are
63 /// providing proof-of-payment for less than the value you expected!).
66 /// Indicates an outbound payment we made succeeded (ie it made it all the way to its target
67 /// and we got back the payment preimage for it).
68 /// Note that duplicative PaymentSent Events may be generated - it is your responsibility to
69 /// deduplicate them by payment_preimage (which MUST be unique)!
71 /// The preimage to the hash given to ChannelManager::send_payment.
72 /// Note that this serves as a payment receipt, if you wish to have such a thing, you must
74 payment_preimage: PaymentPreimage,
76 /// Indicates an outbound payment we made failed. Probably some intermediary node dropped
77 /// something. You may wish to retry with a different route.
78 /// Note that duplicative PaymentFailed Events may be generated - it is your responsibility to
79 /// deduplicate them by payment_hash (which MUST be unique)!
81 /// The hash which was given to ChannelManager::send_payment.
82 payment_hash: PaymentHash,
83 /// Indicates the payment was rejected for some reason by the recipient. This implies that
84 /// the payment has failed, not just the route in question. If this is not set, you may
85 /// retry the payment via a different route.
86 rejected_by_dest: bool,
88 error_code: Option<u16>,
90 /// Used to indicate that ChannelManager::process_pending_htlc_forwards should be called at a
91 /// time in the future.
92 PendingHTLCsForwardable {
93 /// The minimum amount of time that should be waited prior to calling
94 /// process_pending_htlc_forwards. To increase the effort required to correlate payments,
95 /// you should wait a random amount of time in roughly the range (now + time_forwardable,
96 /// now + 5*time_forwardable).
97 time_forwardable: Duration,
99 /// Used to indicate that an output was generated on-chain which you should know how to spend.
100 /// Such an output will *not* ever be spent by rust-lightning, and are not at risk of your
101 /// counterparty spending them due to some kind of timeout. Thus, you need to store them
102 /// somewhere and spend them when you create on-chain transactions.
104 /// The outputs which you should store as spendable by you.
105 outputs: Vec<SpendableOutputDescriptor>,
109 impl Writeable for Event {
110 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
112 &Event::FundingGenerationReady { .. } => {
114 // We never write out FundingGenerationReady events as, upon disconnection, peers
115 // drop any channels which have not yet exchanged funding_signed.
117 &Event::FundingBroadcastSafe { ref funding_txo, ref user_channel_id } => {
119 funding_txo.write(writer)?;
120 user_channel_id.write(writer)?;
122 &Event::PaymentReceived { ref payment_hash, ref amt } => {
124 payment_hash.write(writer)?;
127 &Event::PaymentSent { ref payment_preimage } => {
129 payment_preimage.write(writer)?;
131 &Event::PaymentFailed { ref payment_hash, ref rejected_by_dest,
136 payment_hash.write(writer)?;
137 rejected_by_dest.write(writer)?;
139 error_code.write(writer)?;
141 &Event::PendingHTLCsForwardable { time_forwardable: _ } => {
143 // We don't write the time_fordwardable out at all, as we presume when the user
144 // deserializes us at least that much time has elapsed.
146 &Event::SpendableOutputs { ref outputs } => {
148 (outputs.len() as u64).write(writer)?;
149 for output in outputs.iter() {
150 output.write(writer)?;
157 impl<R: ::std::io::Read> MaybeReadable<R> for Event {
158 fn read(reader: &mut R) -> Result<Option<Self>, msgs::DecodeError> {
159 match Readable::read(reader)? {
161 1u8 => Ok(Some(Event::FundingBroadcastSafe {
162 funding_txo: Readable::read(reader)?,
163 user_channel_id: Readable::read(reader)?,
165 2u8 => Ok(Some(Event::PaymentReceived {
166 payment_hash: Readable::read(reader)?,
167 amt: Readable::read(reader)?,
169 3u8 => Ok(Some(Event::PaymentSent {
170 payment_preimage: Readable::read(reader)?,
172 4u8 => Ok(Some(Event::PaymentFailed {
173 payment_hash: Readable::read(reader)?,
174 rejected_by_dest: Readable::read(reader)?,
176 error_code: Readable::read(reader)?,
178 5u8 => Ok(Some(Event::PendingHTLCsForwardable {
179 time_forwardable: Duration::from_secs(0)
182 let outputs_len: u64 = Readable::read(reader)?;
183 let mut outputs = Vec::new();
184 for _ in 0..outputs_len {
185 outputs.push(Readable::read(reader)?);
187 Ok(Some(Event::SpendableOutputs { outputs }))
189 _ => Err(msgs::DecodeError::InvalidValue)
194 /// An event generated by ChannelManager which indicates a message should be sent to a peer (or
195 /// broadcast to most peers).
196 /// These events are handled by PeerManager::process_events if you are using a PeerManager.
198 pub enum MessageSendEvent {
199 /// Used to indicate that we've accepted a channel open and should send the accept_channel
200 /// message provided to the given peer.
202 /// The node_id of the node which should receive this message
204 /// The message which should be sent.
205 msg: msgs::AcceptChannel,
207 /// Used to indicate that we've initiated a channel open and should send the open_channel
208 /// message provided to the given peer.
210 /// The node_id of the node which should receive this message
212 /// The message which should be sent.
213 msg: msgs::OpenChannel,
215 /// Used to indicate that a funding_created message should be sent to the peer with the given node_id.
217 /// The node_id of the node which should receive this message
219 /// The message which should be sent.
220 msg: msgs::FundingCreated,
222 /// Used to indicate that a funding_signed message should be sent to the peer with the given node_id.
224 /// The node_id of the node which should receive this message
226 /// The message which should be sent.
227 msg: msgs::FundingSigned,
229 /// Used to indicate that a funding_locked message should be sent to the peer with the given node_id.
231 /// The node_id of the node which should receive these message(s)
233 /// The funding_locked message which should be sent.
234 msg: msgs::FundingLocked,
236 /// Used to indicate that an announcement_signatures message should be sent to the peer with the given node_id.
237 SendAnnouncementSignatures {
238 /// The node_id of the node which should receive these message(s)
240 /// The announcement_signatures message which should be sent.
241 msg: msgs::AnnouncementSignatures,
243 /// Used to indicate that a series of HTLC update messages, as well as a commitment_signed
244 /// message should be sent to the peer with the given node_id.
246 /// The node_id of the node which should receive these message(s)
248 /// The update messages which should be sent. ALL messages in the struct should be sent!
249 updates: msgs::CommitmentUpdate,
251 /// Used to indicate that a revoke_and_ack message should be sent to the peer with the given node_id.
253 /// The node_id of the node which should receive this message
255 /// The message which should be sent.
256 msg: msgs::RevokeAndACK,
258 /// Used to indicate that a closing_signed message should be sent to the peer with the given node_id.
260 /// The node_id of the node which should receive this message
262 /// The message which should be sent.
263 msg: msgs::ClosingSigned,
265 /// Used to indicate that a shutdown message should be sent to the peer with the given node_id.
267 /// The node_id of the node which should receive this message
269 /// The message which should be sent.
272 /// Used to indicate that a channel_reestablish message should be sent to the peer with the given node_id.
273 SendChannelReestablish {
274 /// The node_id of the node which should receive this message
276 /// The message which should be sent.
277 msg: msgs::ChannelReestablish,
279 /// Used to indicate that a channel_announcement and channel_update should be broadcast to all
280 /// peers (except the peer with node_id either msg.contents.node_id_1 or msg.contents.node_id_2).
281 BroadcastChannelAnnouncement {
282 /// The channel_announcement which should be sent.
283 msg: msgs::ChannelAnnouncement,
284 /// The followup channel_update which should be sent.
285 update_msg: msgs::ChannelUpdate,
287 /// Used to indicate that a channel_update should be broadcast to all peers.
288 BroadcastChannelUpdate {
289 /// The channel_update which should be sent.
290 msg: msgs::ChannelUpdate,
292 /// Broadcast an error downstream to be handled
294 /// The node_id of the node which should receive this message
296 /// The action which should be taken.
297 action: msgs::ErrorAction
299 /// When a payment fails we may receive updates back from the hop where it failed. In such
300 /// cases this event is generated so that we can inform the router of this information.
301 PaymentFailureNetworkUpdate {
302 /// The channel/node update which should be sent to router
303 update: msgs::HTLCFailChannelUpdate,
307 /// A trait indicating an object may generate message send events
308 pub trait MessageSendEventsProvider {
309 /// Gets the list of pending events which were generated by previous actions, clearing the list
311 fn get_and_clear_pending_msg_events(&self) -> Vec<MessageSendEvent>;
314 /// A trait indicating an object may generate events
315 pub trait EventsProvider {
316 /// Gets the list of pending events which were generated by previous actions, clearing the list
318 fn get_and_clear_pending_events(&self) -> Vec<Event>;