Expand `chain::Listen` trivially to accept filtered block data

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

diff --git a/lightning/src/chain/mod.rs b/lightning/src/chain/mod.rs
index 55755073bb1a7546d39ce65fd2fd8c9d0e9b4af5..24eb09e7090b212ea9867aba9844ed6993c83735 100644 (file)
--- a/lightning/src/chain/mod.rs
+++ b/lightning/src/chain/mod.rs
@@ -87,9 +87,20 @@ pub trait Access {
 /// sourcing chain data using a block-oriented API should prefer this interface over [`Confirm`].
 /// Such clients fetch the entire header chain whereas clients using [`Confirm`] only fetch headers
 /// when needed.
+///
+/// By using [`Listen::filtered_block_connected`] this interface supports clients fetching the
+/// entire header chain and only blocks with matching transaction data using BIP 157 filters or
+/// other similar filtering.
 pub trait Listen {
+       /// Notifies the listener that a block was added at the given height, with the transaction data
+       /// possibly filtered.
+       fn filtered_block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32);
+
        /// Notifies the listener that a block was added at the given height.
-       fn block_connected(&self, block: &Block, height: u32);
+       fn block_connected(&self, block: &Block, height: u32) {
+               let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
+               self.filtered_block_connected(&block.header, &txdata, height);
+       }
 
        /// Notifies the listener that a block was removed at the given height.
        fn block_disconnected(&self, header: &BlockHeader, height: u32);
@@ -285,6 +296,10 @@ pub trait Watch<ChannelSigner: Sign> {
        /// Returns any monitor events since the last call. Subsequent calls must only return new
        /// events.
        ///
+       /// Note that after any block- or transaction-connection calls to a [`ChannelMonitor`], no
+       /// further events may be returned here until the [`ChannelMonitor`] has been fully persisted
+       /// to disk.
+       ///
        /// For details on asynchronous [`ChannelMonitor`] updating and returning
        /// [`MonitorEvent::UpdateCompleted`] here, see [`ChannelMonitorUpdateErr::TemporaryFailure`].
        fn release_pending_monitor_events(&self) -> Vec<MonitorEvent>;
@@ -351,8 +366,8 @@ pub struct WatchedOutput {
 }
 
 impl<T: Listen> Listen for core::ops::Deref<Target = T> {
-       fn block_connected(&self, block: &Block, height: u32) {
-               (**self).block_connected(block, height);
+       fn filtered_block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
+               (**self).filtered_block_connected(header, txdata, height);
        }
 
        fn block_disconnected(&self, header: &BlockHeader, height: u32) {
@@ -365,9 +380,9 @@ where
        T::Target: Listen,
        U::Target: Listen,
 {
-       fn block_connected(&self, block: &Block, height: u32) {
-               self.0.block_connected(block, height);
-               self.1.block_connected(block, height);
+       fn filtered_block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
+               self.0.filtered_block_connected(header, txdata, height);
+               self.1.filtered_block_connected(header, txdata, height);
        }
 
        fn block_disconnected(&self, header: &BlockHeader, height: u32) {