-use crate::{AsyncBlockSourceResult, BlockHeaderData, BlockSource, BlockSourceError, BlockSourceResult};
+//! Adapters that make one or more [`BlockSource`]s simpler to poll for new chain tip transitions.
+
+use crate::{AsyncBlockSourceResult, BlockData, BlockHeaderData, BlockSource, BlockSourceError, BlockSourceResult};
-use bitcoin::blockdata::block::Block;
use bitcoin::hash_types::BlockHash;
use bitcoin::network::constants::Network;
+use lightning::chain::BestBlock;
-use std::ops::DerefMut;
+use std::ops::Deref;
/// The `Poll` trait defines behavior for polling block sources for a chain tip and retrieving
/// related chain data. It serves as an adapter for `BlockSource`.
/// [`ChainPoller`]: ../struct.ChainPoller.html
pub trait Poll {
/// Returns a chain tip in terms of its relationship to the provided chain tip.
- fn poll_chain_tip<'a>(&'a mut self, best_known_chain_tip: ValidatedBlockHeader) ->
+ fn poll_chain_tip<'a>(&'a self, best_known_chain_tip: ValidatedBlockHeader) ->
AsyncBlockSourceResult<'a, ChainTip>;
/// Returns the header that preceded the given header in the chain.
- fn look_up_previous_header<'a>(&'a mut self, header: &'a ValidatedBlockHeader) ->
+ fn look_up_previous_header<'a>(&'a self, header: &'a ValidatedBlockHeader) ->
AsyncBlockSourceResult<'a, ValidatedBlockHeader>;
/// Returns the block associated with the given header.
- fn fetch_block<'a>(&'a mut self, header: &'a ValidatedBlockHeader) ->
+ fn fetch_block<'a>(&'a self, header: &'a ValidatedBlockHeader) ->
AsyncBlockSourceResult<'a, ValidatedBlock>;
}
/// A chain tip relative to another chain tip in terms of block hash and chainwork.
-#[derive(Clone, Debug, PartialEq)]
+#[derive(Clone, Debug, PartialEq, Eq)]
pub enum ChainTip {
/// A chain tip with the same hash as another chain's tip.
Common,
}
/// The `Validate` trait defines behavior for validating chain data.
-pub(crate) trait Validate {
+///
+/// This trait is sealed and not meant to be implemented outside of this crate.
+pub trait Validate: sealed::Validate {
/// The validated data wrapper which can be dereferenced to obtain the validated data.
type T: std::ops::Deref<Target = Self>;
type T = ValidatedBlockHeader;
fn validate(self, block_hash: BlockHash) -> BlockSourceResult<Self::T> {
- self.header
+ let pow_valid_block_hash = self.header
.validate_pow(&self.header.target())
- .or_else(|e| Err(BlockSourceError::persistent(e)))?;
+ .map_err(BlockSourceError::persistent)?;
- // TODO: Use the result of validate_pow instead of recomputing the block hash once upstream.
- if self.header.block_hash() != block_hash {
+ if pow_valid_block_hash != block_hash {
return Err(BlockSourceError::persistent("invalid block hash"));
}
}
}
-impl Validate for Block {
+impl Validate for BlockData {
type T = ValidatedBlock;
fn validate(self, block_hash: BlockHash) -> BlockSourceResult<Self::T> {
- self.header
- .validate_pow(&self.header.target())
- .or_else(|e| Err(BlockSourceError::persistent(e)))?;
+ let header = match &self {
+ BlockData::FullBlock(block) => &block.header,
+ BlockData::HeaderOnly(header) => header,
+ };
+
+ let pow_valid_block_hash = header
+ .validate_pow(&header.target())
+ .map_err(BlockSourceError::persistent)?;
- // TODO: Use the result of validate_pow instead of recomputing the block hash once upstream.
- if self.block_hash() != block_hash {
+ if pow_valid_block_hash != block_hash {
return Err(BlockSourceError::persistent("invalid block hash"));
}
- if !self.check_merkle_root() {
- return Err(BlockSourceError::persistent("invalid merkle root"));
- }
+ if let BlockData::FullBlock(block) = &self {
+ if !block.check_merkle_root() {
+ return Err(BlockSourceError::persistent("invalid merkle root"));
+ }
- if !self.check_witness_commitment() {
- return Err(BlockSourceError::persistent("invalid witness commitment"));
+ if !block.check_witness_commitment() {
+ return Err(BlockSourceError::persistent("invalid witness commitment"));
+ }
}
Ok(ValidatedBlock { block_hash, inner: self })
}
/// A block header with validated proof of work and corresponding block hash.
-#[derive(Clone, Copy, Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub struct ValidatedBlockHeader {
pub(crate) block_hash: BlockHash,
inner: BlockHeaderData,
Ok(())
}
+
+ /// Returns the [`BestBlock`] corresponding to this validated block header, which can be passed
+ /// into [`ChannelManager::new`] as part of its [`ChainParameters`]. Useful for ensuring that
+ /// the [`SpvClient`] and [`ChannelManager`] are initialized to the same block during a fresh
+ /// start.
+ ///
+ /// [`SpvClient`]: crate::SpvClient
+ /// [`ChainParameters`]: lightning::ln::channelmanager::ChainParameters
+ /// [`ChannelManager`]: lightning::ln::channelmanager::ChannelManager
+ /// [`ChannelManager::new`]: lightning::ln::channelmanager::ChannelManager::new
+ pub fn to_best_block(&self) -> BestBlock {
+ BestBlock::new(self.block_hash, self.inner.height)
+ }
}
/// A block with validated data against its transaction list and corresponding block hash.
pub struct ValidatedBlock {
pub(crate) block_hash: BlockHash,
- inner: Block,
+ inner: BlockData,
}
impl std::ops::Deref for ValidatedBlock {
- type Target = Block;
+ type Target = BlockData;
fn deref(&self) -> &Self::Target {
&self.inner
}
}
+mod sealed {
+ /// Used to prevent implementing [`super::Validate`] outside the crate but still allow its use.
+ pub trait Validate {}
+
+ impl Validate for crate::BlockHeaderData {}
+ impl Validate for crate::BlockData {}
+}
+
/// The canonical `Poll` implementation used for a single `BlockSource`.
///
-/// Other `Poll` implementations must be built using `ChainPoller` as it provides the only means of
-/// validating chain data.
-pub struct ChainPoller<B: DerefMut<Target=T> + Sized + Sync + Send, T: BlockSource> {
+/// Other `Poll` implementations should be built using `ChainPoller` as it provides the simplest way
+/// of validating chain data and checking consistency.
+pub struct ChainPoller<B: Deref<Target=T> + Sized + Send + Sync, T: BlockSource + ?Sized> {
block_source: B,
network: Network,
}
-impl<B: DerefMut<Target=T> + Sized + Sync + Send, T: BlockSource> ChainPoller<B, T> {
+impl<B: Deref<Target=T> + Sized + Send + Sync, T: BlockSource + ?Sized> ChainPoller<B, T> {
/// Creates a new poller for the given block source.
///
/// If the `network` parameter is mainnet, then the difficulty between blocks is checked for
}
}
-impl<B: DerefMut<Target=T> + Sized + Sync + Send, T: BlockSource> Poll for ChainPoller<B, T> {
- fn poll_chain_tip<'a>(&'a mut self, best_known_chain_tip: ValidatedBlockHeader) ->
+impl<B: Deref<Target=T> + Sized + Send + Sync, T: BlockSource + ?Sized> Poll for ChainPoller<B, T> {
+ fn poll_chain_tip<'a>(&'a self, best_known_chain_tip: ValidatedBlockHeader) ->
AsyncBlockSourceResult<'a, ChainTip>
{
Box::pin(async move {
})
}
- fn look_up_previous_header<'a>(&'a mut self, header: &'a ValidatedBlockHeader) ->
+ fn look_up_previous_header<'a>(&'a self, header: &'a ValidatedBlockHeader) ->
AsyncBlockSourceResult<'a, ValidatedBlockHeader>
{
Box::pin(async move {
})
}
- fn fetch_block<'a>(&'a mut self, header: &'a ValidatedBlockHeader) ->
+ fn fetch_block<'a>(&'a self, header: &'a ValidatedBlockHeader) ->
AsyncBlockSourceResult<'a, ValidatedBlock>
{
Box::pin(async move {
let best_known_chain_tip = chain.tip();
chain.disconnect_tip();
- let mut poller = ChainPoller::new(&mut chain, Network::Bitcoin);
+ let poller = ChainPoller::new(&chain, Network::Bitcoin);
match poller.poll_chain_tip(best_known_chain_tip).await {
Err(e) => {
assert_eq!(e.kind(), BlockSourceErrorKind::Transient);
#[tokio::test]
async fn poll_chain_without_headers() {
- let mut chain = Blockchain::default().with_height(1).without_headers();
+ let chain = Blockchain::default().with_height(1).without_headers();
let best_known_chain_tip = chain.at_height(0);
- let mut poller = ChainPoller::new(&mut chain, Network::Bitcoin);
+ let poller = ChainPoller::new(&chain, Network::Bitcoin);
match poller.poll_chain_tip(best_known_chain_tip).await {
Err(e) => {
assert_eq!(e.kind(), BlockSourceErrorKind::Persistent);
chain.blocks.last_mut().unwrap().header.bits =
BlockHeader::compact_target_from_u256(&Uint256::from_be_bytes([0; 32]));
- let mut poller = ChainPoller::new(&mut chain, Network::Bitcoin);
+ let poller = ChainPoller::new(&chain, Network::Bitcoin);
match poller.poll_chain_tip(best_known_chain_tip).await {
Err(e) => {
assert_eq!(e.kind(), BlockSourceErrorKind::Persistent);
#[tokio::test]
async fn poll_chain_with_malformed_headers() {
- let mut chain = Blockchain::default().with_height(1).malformed_headers();
+ let chain = Blockchain::default().with_height(1).malformed_headers();
let best_known_chain_tip = chain.at_height(0);
- let mut poller = ChainPoller::new(&mut chain, Network::Bitcoin);
+ let poller = ChainPoller::new(&chain, Network::Bitcoin);
match poller.poll_chain_tip(best_known_chain_tip).await {
Err(e) => {
assert_eq!(e.kind(), BlockSourceErrorKind::Persistent);
#[tokio::test]
async fn poll_chain_with_common_tip() {
- let mut chain = Blockchain::default().with_height(0);
+ let chain = Blockchain::default().with_height(0);
let best_known_chain_tip = chain.tip();
- let mut poller = ChainPoller::new(&mut chain, Network::Bitcoin);
+ let poller = ChainPoller::new(&chain, Network::Bitcoin);
match poller.poll_chain_tip(best_known_chain_tip).await {
Err(e) => panic!("Unexpected error: {:?}", e),
Ok(tip) => assert_eq!(tip, ChainTip::Common),
let worse_chain_tip = chain.tip();
assert_eq!(best_known_chain_tip.chainwork, worse_chain_tip.chainwork);
- let mut poller = ChainPoller::new(&mut chain, Network::Bitcoin);
+ let poller = ChainPoller::new(&chain, Network::Bitcoin);
match poller.poll_chain_tip(best_known_chain_tip).await {
Err(e) => panic!("Unexpected error: {:?}", e),
Ok(tip) => assert_eq!(tip, ChainTip::Worse(worse_chain_tip)),
chain.disconnect_tip();
let worse_chain_tip = chain.tip();
- let mut poller = ChainPoller::new(&mut chain, Network::Bitcoin);
+ let poller = ChainPoller::new(&chain, Network::Bitcoin);
match poller.poll_chain_tip(best_known_chain_tip).await {
Err(e) => panic!("Unexpected error: {:?}", e),
Ok(tip) => assert_eq!(tip, ChainTip::Worse(worse_chain_tip)),
#[tokio::test]
async fn poll_chain_with_better_tip() {
- let mut chain = Blockchain::default().with_height(1);
+ let chain = Blockchain::default().with_height(1);
let best_known_chain_tip = chain.at_height(0);
let better_chain_tip = chain.tip();
- let mut poller = ChainPoller::new(&mut chain, Network::Bitcoin);
+ let poller = ChainPoller::new(&chain, Network::Bitcoin);
match poller.poll_chain_tip(best_known_chain_tip).await {
Err(e) => panic!("Unexpected error: {:?}", e),
Ok(tip) => assert_eq!(tip, ChainTip::Better(better_chain_tip)),