Enable signing a justice tx using the channel monitor

[rust-lightning] / lightning / src / chain / chainmonitor.rs

diff --git a/lightning/src/chain/chainmonitor.rs b/lightning/src/chain/chainmonitor.rs
index 16a02b54a3bbe4e848f194f376a541c6bafa860a..7d698a220676b8dfd7c9a0df41b0b09f0799e2e9 100644 (file)
--- a/lightning/src/chain/chainmonitor.rs
+++ b/lightning/src/chain/chainmonitor.rs
@@ -94,6 +94,17 @@ impl MonitorUpdateId {
 ///    [`ChannelMonitorUpdateStatus::PermanentFailure`], in which case the channel will likely be
 ///    closed without broadcasting the latest state. See
 ///    [`ChannelMonitorUpdateStatus::PermanentFailure`] for more details.
+///
+/// Third-party watchtowers may be built as a part of an implementation of this trait, with the
+/// advantage that you can control whether to resume channel operation depending on if an update
+/// has been persisted to a watchtower. For this, you may find the following methods useful:
+/// [`ChannelMonitor::initial_counterparty_commitment_tx`],
+/// [`ChannelMonitor::counterparty_commitment_txs_from_update`],
+/// [`ChannelMonitor::sign_to_local_justice_tx`], [`TrustedCommitmentTransaction::revokeable_output_index`],
+/// [`TrustedCommitmentTransaction::build_to_local_justice_tx`].
+///
+/// [`TrustedCommitmentTransaction::revokeable_output_index`]: crate::ln::chan_utils::TrustedCommitmentTransaction::revokeable_output_index
+/// [`TrustedCommitmentTransaction::build_to_local_justice_tx`]: crate::ln::chan_utils::TrustedCommitmentTransaction::build_to_local_justice_tx
 pub trait Persist<ChannelSigner: WriteableEcdsaChannelSigner> {
        /// Persist a new channel's data in response to a [`chain::Watch::watch_channel`] call. This is
        /// called by [`ChannelManager`] for new channels, or may be called directly, e.g. on startup.