X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning-block-sync%2Fsrc%2Finit.rs;h=83e356919b8e231a8d4a3bda41b0d65645e146fc;hb=2cb5b1af992263e219f47c1f09763ffd17fcda15;hp=da9895ae7213f0a529aa7d77f4d84f8ca8d077fd;hpb=e77b16049b50a2e6630dc1a7902b9742122bb32f;p=rust-lightning

diff --git a/lightning-block-sync/src/init.rs b/lightning-block-sync/src/init.rs
index da9895ae..83e35691 100644
--- a/lightning-block-sync/src/init.rs
+++ b/lightning-block-sync/src/init.rs
@@ -7,6 +7,18 @@ use bitcoin::network::constants::Network;
 
 use lightning::chain;
 
+/// Returns a validated block header of the source's best chain tip.
+///
+/// Upon success, the returned header can be used to initialize [`SpvClient`]. Useful during a fresh
+/// start when there are no chain listeners to sync yet.
+pub async fn validate_best_block_header<B: BlockSource>(block_source: &mut B) ->
+BlockSourceResult<ValidatedBlockHeader> {
+	let (best_block_hash, best_block_height) = block_source.get_best_block().await?;
+	block_source
+		.get_header(&best_block_hash, best_block_height).await?
+		.validate(best_block_hash)
+}
+
 /// Performs a one-time sync of chain listeners using a single *trusted* block source, bringing each
 /// listener's view of the chain from its paired block hash to `block_source`'s best chain tip.
 ///
@@ -38,7 +50,6 @@ use lightning::chain;
 ///
 /// use lightning_block_sync::*;
 ///
-/// use std::cell::RefCell;
 /// use std::io::Cursor;
 ///
 /// async fn init_sync<
@@ -83,7 +94,7 @@ use lightning::chain;
 ///
 /// 	// Synchronize any channel monitors and the channel manager to be on the best block.
 /// 	let mut cache = UnboundedCache::new();
-/// 	let mut monitor_listener = (RefCell::new(monitor), &*tx_broadcaster, &*fee_estimator, &*logger);
+/// 	let mut monitor_listener = (monitor, &*tx_broadcaster, &*fee_estimator, &*logger);
 /// 	let listeners = vec![
 /// 		(monitor_block_hash, &mut monitor_listener as &mut dyn chain::Listen),
 /// 		(manager_block_hash, &mut manager as &mut dyn chain::Listen),
@@ -92,7 +103,7 @@ use lightning::chain;
 /// 		block_source, Network::Bitcoin, &mut cache, listeners).await.unwrap();
 ///
 /// 	// Allow the chain monitor to watch any channels.
-/// 	let monitor = monitor_listener.0.into_inner();
+/// 	let monitor = monitor_listener.0;
 /// 	chain_monitor.watch_channel(monitor.get_funding_txo().0, monitor);
 ///
 /// 	// Create an SPV client to notify the chain monitor and channel manager of block events.
@@ -111,10 +122,7 @@ pub async fn synchronize_listeners<B: BlockSource, C: Cache>(
 	header_cache: &mut C,
 	mut chain_listeners: Vec<(BlockHash, &mut dyn chain::Listen)>,
 ) -> BlockSourceResult<ValidatedBlockHeader> {
-	let (best_block_hash, best_block_height) = block_source.get_best_block().await?;
-	let best_header = block_source
-		.get_header(&best_block_hash, best_block_height).await?
-		.validate(best_block_hash)?;
+	let best_header = validate_best_block_header(block_source).await?;
 
 	// Fetch the header for the block hash paired with each listener.
 	let mut chain_listeners_with_old_headers = Vec::new();