X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning-block-sync%2Fsrc%2Flib.rs;h=db536fe7d43778ccb062be5813548f2072353a44;hb=81c6bdc953ce3191e2428a3575e5994381f31c1f;hp=5ed8689fb965e00ee1d7305e790207d339d2c9c0;hpb=8505382b197ee9469028b2ea6062fe2489aee6c1;p=rust-lightning diff --git a/lightning-block-sync/src/lib.rs b/lightning-block-sync/src/lib.rs index 5ed8689f..db536fe7 100644 --- a/lightning-block-sync/src/lib.rs +++ b/lightning-block-sync/src/lib.rs @@ -19,6 +19,7 @@ #[cfg(any(feature = "rest-client", feature = "rpc-client"))] pub mod http; +pub mod init; pub mod poll; #[cfg(feature = "rest-client")] @@ -42,7 +43,11 @@ use bitcoin::blockdata::block::{Block, BlockHeader}; use bitcoin::hash_types::BlockHash; use bitcoin::util::uint::Uint256; +use lightning::chain; +use lightning::chain::Listen; + use std::future::Future; +use std::ops::Deref; use std::pin::Pin; /// Abstract type for retrieving block headers and data. @@ -154,22 +159,11 @@ pub struct BlockHeaderData { /// custom cache eviction policy. This offers flexibility to those sensitive to resource usage. /// Hence, there is a trade-off between a lower memory footprint and potentially increased network /// I/O as headers are re-fetched during fork detection. -pub struct SpvClient { +pub struct SpvClient<'a, P: Poll, C: Cache, L: Deref> +where L::Target: chain::Listen { chain_tip: ValidatedBlockHeader, chain_poller: P, - chain_notifier: ChainNotifier, - chain_listener: L, -} - -/// Adaptor used for notifying when blocks have been connected or disconnected from the chain. -/// -/// Used when needing to replay chain data upon startup or as new chain events occur. -pub trait ChainListener { - /// Notifies the listener that a block was added at the given height. - fn block_connected(&mut self, block: &Block, height: u32); - - /// Notifies the listener that a block was removed at the given height. - fn block_disconnected(&mut self, header: &BlockHeader, height: u32); + chain_notifier: ChainNotifier<'a, C, L>, } /// The `Cache` trait defines behavior for managing a block header cache, where block headers are @@ -214,7 +208,7 @@ impl Cache for UnboundedCache { } } -impl SpvClient { +impl<'a, P: Poll, C: Cache, L: Deref> SpvClient<'a, P, C, L> where L::Target: chain::Listen { /// Creates a new SPV client using `chain_tip` as the best known chain tip. /// /// Subsequent calls to [`poll_best_tip`] will poll for the best chain tip using the given chain @@ -228,11 +222,11 @@ impl SpvClient { pub fn new( chain_tip: ValidatedBlockHeader, chain_poller: P, - header_cache: C, + header_cache: &'a mut C, chain_listener: L, ) -> Self { - let chain_notifier = ChainNotifier { header_cache }; - Self { chain_tip, chain_poller, chain_notifier, chain_listener } + let chain_notifier = ChainNotifier { header_cache, chain_listener }; + Self { chain_tip, chain_poller, chain_notifier } } /// Polls for the best tip and updates the chain listener with any connected or disconnected @@ -262,7 +256,7 @@ impl SpvClient { /// blocks. Returns whether there were any such blocks. async fn update_chain_tip(&mut self, best_chain_tip: ValidatedBlockHeader) -> bool { match self.chain_notifier.synchronize_listener( - best_chain_tip, &self.chain_tip, &mut self.chain_poller, &mut self.chain_listener).await + best_chain_tip, &self.chain_tip, &mut self.chain_poller).await { Ok(_) => { self.chain_tip = best_chain_tip; @@ -279,10 +273,13 @@ impl SpvClient { /// Notifies [listeners] of blocks that have been connected or disconnected from the chain. /// -/// [listeners]: trait.ChainListener.html -struct ChainNotifier { +/// [listeners]: ../../lightning/chain/trait.Listen.html +pub struct ChainNotifier<'a, C: Cache, L: Deref> where L::Target: chain::Listen { /// Cache for looking up headers before fetching from a block source. - header_cache: C, + header_cache: &'a mut C, + + /// Listener that will be notified of connected or disconnected blocks. + chain_listener: L, } /// Changes made to the chain between subsequent polls that transformed it from having one chain tip @@ -291,6 +288,11 @@ struct ChainNotifier { /// Blocks are given in height-descending order. Therefore, blocks are first disconnected in order /// before new blocks are connected in reverse order. struct ChainDifference { + /// The most recent ancestor common between the chain tips. + /// + /// If there are any disconnected blocks, this is where the chain forked. + common_ancestor: ValidatedBlockHeader, + /// Blocks that were disconnected from the chain since the last poll. disconnected_blocks: Vec, @@ -298,45 +300,28 @@ struct ChainDifference { connected_blocks: Vec, } -impl ChainNotifier { - /// Finds the fork point between `new_header` and `old_header`, disconnecting blocks from - /// `old_header` to get to that point and then connecting blocks until `new_header`. +impl<'a, C: Cache, L: Deref> ChainNotifier<'a, C, L> where L::Target: chain::Listen { + /// Finds the first common ancestor between `new_header` and `old_header`, disconnecting blocks + /// from `old_header` to get to that point and then connecting blocks until `new_header`. /// /// Validates headers along the transition path, but doesn't fetch blocks until the chain is /// disconnected to the fork point. Thus, this may return an `Err` that includes where the tip /// ended up which may not be `new_header`. Note that the returned `Err` contains `Some` header /// if and only if the transition from `old_header` to `new_header` is valid. - async fn synchronize_listener( + async fn synchronize_listener( &mut self, new_header: ValidatedBlockHeader, old_header: &ValidatedBlockHeader, chain_poller: &mut P, - chain_listener: &mut L, ) -> Result<(), (BlockSourceError, Option)> { - let mut difference = self.find_difference(new_header, old_header, chain_poller).await + let difference = self.find_difference(new_header, old_header, chain_poller).await .map_err(|e| (e, None))?; - - let mut new_tip = *old_header; - for header in difference.disconnected_blocks.drain(..) { - if let Some(cached_header) = self.header_cache.block_disconnected(&header.block_hash) { - assert_eq!(cached_header, header); - } - chain_listener.block_disconnected(&header.header, header.height); - new_tip = header; - } - - for header in difference.connected_blocks.drain(..).rev() { - let block = chain_poller - .fetch_block(&header).await - .or_else(|e| Err((e, Some(new_tip))))?; - debug_assert_eq!(block.block_hash, header.block_hash); - - self.header_cache.block_connected(header.block_hash, header); - chain_listener.block_connected(&block, header.height); - new_tip = header; - } - - Ok(()) + self.disconnect_blocks(difference.disconnected_blocks); + self.connect_blocks( + difference.common_ancestor, + difference.connected_blocks, + chain_poller, + ).await } /// Returns the changes needed to produce the chain with `current_header` as its tip from the @@ -373,7 +358,8 @@ impl ChainNotifier { } } - Ok(ChainDifference { disconnected_blocks, connected_blocks }) + let common_ancestor = current; + Ok(ChainDifference { common_ancestor, disconnected_blocks, connected_blocks }) } /// Returns the previous header for the given header, either by looking it up in the cache or @@ -388,6 +374,37 @@ impl ChainNotifier { None => chain_poller.look_up_previous_header(header).await, } } + + /// Notifies the chain listeners of disconnected blocks. + fn disconnect_blocks(&mut self, mut disconnected_blocks: Vec) { + for header in disconnected_blocks.drain(..) { + if let Some(cached_header) = self.header_cache.block_disconnected(&header.block_hash) { + assert_eq!(cached_header, header); + } + self.chain_listener.block_disconnected(&header.header, header.height); + } + } + + /// Notifies the chain listeners of connected blocks. + async fn connect_blocks( + &mut self, + mut new_tip: ValidatedBlockHeader, + mut connected_blocks: Vec, + chain_poller: &mut P, + ) -> Result<(), (BlockSourceError, Option)> { + for header in connected_blocks.drain(..).rev() { + let block = chain_poller + .fetch_block(&header).await + .or_else(|e| Err((e, Some(new_tip))))?; + debug_assert_eq!(block.block_hash, header.block_hash); + + self.header_cache.block_connected(header.block_hash, header); + self.chain_listener.block_connected(&block, header.height); + new_tip = header; + } + + Ok(()) + } } #[cfg(test)] @@ -403,8 +420,9 @@ mod spv_client_tests { let best_tip = chain.at_height(1); let poller = poll::ChainPoller::new(&mut chain, Network::Testnet); - let cache = UnboundedCache::new(); - let mut client = SpvClient::new(best_tip, poller, cache, NullChainListener {}); + let mut cache = UnboundedCache::new(); + let mut listener = NullChainListener {}; + let mut client = SpvClient::new(best_tip, poller, &mut cache, &mut listener); match client.poll_best_tip().await { Err(e) => { assert_eq!(e.kind(), BlockSourceErrorKind::Persistent); @@ -421,8 +439,9 @@ mod spv_client_tests { let common_tip = chain.tip(); let poller = poll::ChainPoller::new(&mut chain, Network::Testnet); - let cache = UnboundedCache::new(); - let mut client = SpvClient::new(common_tip, poller, cache, NullChainListener {}); + let mut cache = UnboundedCache::new(); + let mut listener = NullChainListener {}; + let mut client = SpvClient::new(common_tip, poller, &mut cache, &mut listener); match client.poll_best_tip().await { Err(e) => panic!("Unexpected error: {:?}", e), Ok((chain_tip, blocks_connected)) => { @@ -440,8 +459,9 @@ mod spv_client_tests { let old_tip = chain.at_height(1); let poller = poll::ChainPoller::new(&mut chain, Network::Testnet); - let cache = UnboundedCache::new(); - let mut client = SpvClient::new(old_tip, poller, cache, NullChainListener {}); + let mut cache = UnboundedCache::new(); + let mut listener = NullChainListener {}; + let mut client = SpvClient::new(old_tip, poller, &mut cache, &mut listener); match client.poll_best_tip().await { Err(e) => panic!("Unexpected error: {:?}", e), Ok((chain_tip, blocks_connected)) => { @@ -459,8 +479,9 @@ mod spv_client_tests { let old_tip = chain.at_height(1); let poller = poll::ChainPoller::new(&mut chain, Network::Testnet); - let cache = UnboundedCache::new(); - let mut client = SpvClient::new(old_tip, poller, cache, NullChainListener {}); + let mut cache = UnboundedCache::new(); + let mut listener = NullChainListener {}; + let mut client = SpvClient::new(old_tip, poller, &mut cache, &mut listener); match client.poll_best_tip().await { Err(e) => panic!("Unexpected error: {:?}", e), Ok((chain_tip, blocks_connected)) => { @@ -478,8 +499,9 @@ mod spv_client_tests { let old_tip = chain.at_height(1); let poller = poll::ChainPoller::new(&mut chain, Network::Testnet); - let cache = UnboundedCache::new(); - let mut client = SpvClient::new(old_tip, poller, cache, NullChainListener {}); + let mut cache = UnboundedCache::new(); + let mut listener = NullChainListener {}; + let mut client = SpvClient::new(old_tip, poller, &mut cache, &mut listener); match client.poll_best_tip().await { Err(e) => panic!("Unexpected error: {:?}", e), Ok((chain_tip, blocks_connected)) => { @@ -498,8 +520,9 @@ mod spv_client_tests { let worse_tip = chain.tip(); let poller = poll::ChainPoller::new(&mut chain, Network::Testnet); - let cache = UnboundedCache::new(); - let mut client = SpvClient::new(best_tip, poller, cache, NullChainListener {}); + let mut cache = UnboundedCache::new(); + let mut listener = NullChainListener {}; + let mut client = SpvClient::new(best_tip, poller, &mut cache, &mut listener); match client.poll_best_tip().await { Err(e) => panic!("Unexpected error: {:?}", e), Ok((chain_tip, blocks_connected)) => { @@ -524,12 +547,15 @@ mod chain_notifier_tests { let new_tip = chain.tip(); let old_tip = chain.at_height(1); - let mut listener = MockChainListener::new() + let chain_listener = &MockChainListener::new() .expect_block_connected(*chain.at_height(2)) .expect_block_connected(*new_tip); - let mut notifier = ChainNotifier { header_cache: chain.header_cache(0..=1) }; + let mut notifier = ChainNotifier { + header_cache: &mut chain.header_cache(0..=1), + chain_listener, + }; let mut poller = poll::ChainPoller::new(&mut chain, Network::Testnet); - match notifier.synchronize_listener(new_tip, &old_tip, &mut poller, &mut listener).await { + match notifier.synchronize_listener(new_tip, &old_tip, &mut poller).await { Err((e, _)) => panic!("Unexpected error: {:?}", e), Ok(_) => {}, } @@ -542,10 +568,13 @@ mod chain_notifier_tests { let new_tip = test_chain.tip(); let old_tip = main_chain.tip(); - let mut listener = MockChainListener::new(); - let mut notifier = ChainNotifier { header_cache: main_chain.header_cache(0..=1) }; + let chain_listener = &MockChainListener::new(); + let mut notifier = ChainNotifier { + header_cache: &mut main_chain.header_cache(0..=1), + chain_listener, + }; let mut poller = poll::ChainPoller::new(&mut test_chain, Network::Testnet); - match notifier.synchronize_listener(new_tip, &old_tip, &mut poller, &mut listener).await { + match notifier.synchronize_listener(new_tip, &old_tip, &mut poller).await { Err((e, _)) => { assert_eq!(e.kind(), BlockSourceErrorKind::Persistent); assert_eq!(e.into_inner().as_ref().to_string(), "genesis block reached"); @@ -561,12 +590,15 @@ mod chain_notifier_tests { let new_tip = fork_chain.tip(); let old_tip = main_chain.tip(); - let mut listener = MockChainListener::new() + let chain_listener = &MockChainListener::new() .expect_block_disconnected(*old_tip) .expect_block_connected(*new_tip); - let mut notifier = ChainNotifier { header_cache: main_chain.header_cache(0..=2) }; + let mut notifier = ChainNotifier { + header_cache: &mut main_chain.header_cache(0..=2), + chain_listener, + }; let mut poller = poll::ChainPoller::new(&mut fork_chain, Network::Testnet); - match notifier.synchronize_listener(new_tip, &old_tip, &mut poller, &mut listener).await { + match notifier.synchronize_listener(new_tip, &old_tip, &mut poller).await { Err((e, _)) => panic!("Unexpected error: {:?}", e), Ok(_) => {}, } @@ -580,13 +612,16 @@ mod chain_notifier_tests { let new_tip = fork_chain.tip(); let old_tip = main_chain.tip(); - let mut listener = MockChainListener::new() + let chain_listener = &MockChainListener::new() .expect_block_disconnected(*old_tip) .expect_block_disconnected(*main_chain.at_height(2)) .expect_block_connected(*new_tip); - let mut notifier = ChainNotifier { header_cache: main_chain.header_cache(0..=3) }; + let mut notifier = ChainNotifier { + header_cache: &mut main_chain.header_cache(0..=3), + chain_listener, + }; let mut poller = poll::ChainPoller::new(&mut fork_chain, Network::Testnet); - match notifier.synchronize_listener(new_tip, &old_tip, &mut poller, &mut listener).await { + match notifier.synchronize_listener(new_tip, &old_tip, &mut poller).await { Err((e, _)) => panic!("Unexpected error: {:?}", e), Ok(_) => {}, } @@ -600,13 +635,16 @@ mod chain_notifier_tests { let new_tip = fork_chain.tip(); let old_tip = main_chain.tip(); - let mut listener = MockChainListener::new() + let chain_listener = &MockChainListener::new() .expect_block_disconnected(*old_tip) .expect_block_connected(*fork_chain.at_height(2)) .expect_block_connected(*new_tip); - let mut notifier = ChainNotifier { header_cache: main_chain.header_cache(0..=2) }; + let mut notifier = ChainNotifier { + header_cache: &mut main_chain.header_cache(0..=2), + chain_listener, + }; let mut poller = poll::ChainPoller::new(&mut fork_chain, Network::Testnet); - match notifier.synchronize_listener(new_tip, &old_tip, &mut poller, &mut listener).await { + match notifier.synchronize_listener(new_tip, &old_tip, &mut poller).await { Err((e, _)) => panic!("Unexpected error: {:?}", e), Ok(_) => {}, } @@ -618,10 +656,13 @@ mod chain_notifier_tests { let new_tip = chain.tip(); let old_tip = chain.at_height(1); - let mut listener = MockChainListener::new(); - let mut notifier = ChainNotifier { header_cache: chain.header_cache(0..=1) }; + let chain_listener = &MockChainListener::new(); + let mut notifier = ChainNotifier { + header_cache: &mut chain.header_cache(0..=1), + chain_listener, + }; let mut poller = poll::ChainPoller::new(&mut chain, Network::Testnet); - match notifier.synchronize_listener(new_tip, &old_tip, &mut poller, &mut listener).await { + match notifier.synchronize_listener(new_tip, &old_tip, &mut poller).await { Err((_, tip)) => assert_eq!(tip, None), Ok(_) => panic!("Expected error"), } @@ -633,10 +674,13 @@ mod chain_notifier_tests { let new_tip = chain.tip(); let old_tip = chain.at_height(1); - let mut listener = MockChainListener::new(); - let mut notifier = ChainNotifier { header_cache: chain.header_cache(0..=3) }; + let chain_listener = &MockChainListener::new(); + let mut notifier = ChainNotifier { + header_cache: &mut chain.header_cache(0..=3), + chain_listener, + }; let mut poller = poll::ChainPoller::new(&mut chain, Network::Testnet); - match notifier.synchronize_listener(new_tip, &old_tip, &mut poller, &mut listener).await { + match notifier.synchronize_listener(new_tip, &old_tip, &mut poller).await { Err((_, tip)) => assert_eq!(tip, Some(old_tip)), Ok(_) => panic!("Expected error"), } @@ -648,11 +692,14 @@ mod chain_notifier_tests { let new_tip = chain.tip(); let old_tip = chain.at_height(1); - let mut listener = MockChainListener::new() + let chain_listener = &MockChainListener::new() .expect_block_connected(*chain.at_height(2)); - let mut notifier = ChainNotifier { header_cache: chain.header_cache(0..=3) }; + let mut notifier = ChainNotifier { + header_cache: &mut chain.header_cache(0..=3), + chain_listener, + }; let mut poller = poll::ChainPoller::new(&mut chain, Network::Testnet); - match notifier.synchronize_listener(new_tip, &old_tip, &mut poller, &mut listener).await { + match notifier.synchronize_listener(new_tip, &old_tip, &mut poller).await { Err((_, tip)) => assert_eq!(tip, Some(chain.at_height(2))), Ok(_) => panic!("Expected error"), }