use crate::{AsyncBlockSourceResult, BlockData, BlockHeaderData, BlockSource, BlockSourceError, UnboundedCache};
use crate::poll::{Validate, ValidatedBlockHeader};
use bitcoin::blockdata::block::{Block, BlockHeader};
use bitcoin::blockdata::constants::genesis_block;
use bitcoin::hash_types::BlockHash;
use bitcoin::network::constants::Network;
use bitcoin::util::uint::Uint256;
use bitcoin::util::hash::bitcoin_merkle_root;
use bitcoin::{PackedLockTime, Transaction};
use lightning::chain;
use std::cell::RefCell;
use std::collections::VecDeque;
#[derive(Default)]
pub struct Blockchain {
pub blocks: Vec<Block>,
without_blocks: Option<std::ops::RangeFrom<usize>>,
without_headers: bool,
malformed_headers: bool,
filtered_blocks: bool,
}
impl Blockchain {
pub fn default() -> Self {
Blockchain::with_network(Network::Bitcoin)
}
pub fn with_network(network: Network) -> Self {
let blocks = vec![genesis_block(network)];
Self { blocks, ..Default::default() }
}
pub fn with_height(mut self, height: usize) -> Self {
self.blocks.reserve_exact(height);
let bits = BlockHeader::compact_target_from_u256(&Uint256::from_be_bytes([0xff; 32]));
for i in 1..=height {
let prev_block = &self.blocks[i - 1];
let prev_blockhash = prev_block.block_hash();
let time = prev_block.header.time + height as u32;
let coinbase = Transaction {
version: 0,
lock_time: PackedLockTime::ZERO,
input: vec![],
output: vec![]
};
let merkle_root = bitcoin_merkle_root(vec![coinbase.txid().as_hash()].into_iter()).unwrap();
self.blocks.push(Block {
header: BlockHeader {
version: 0,
prev_blockhash,
merkle_root: merkle_root.into(),
time,
bits,
nonce: 0,
},
txdata: vec![coinbase],
});
}
self
}
pub fn without_blocks(self, range: std::ops::RangeFrom<usize>) -> Self {
Self { without_blocks: Some(range), ..self }
}
pub fn without_headers(self) -> Self {
Self { without_headers: true, ..self }
}
pub fn malformed_headers(self) -> Self {
Self { malformed_headers: true, ..self }
}
pub fn filtered_blocks(self) -> Self {
Self { filtered_blocks: true, ..self }
}
pub fn fork_at_height(&self, height: usize) -> Self {
assert!(height + 1 < self.blocks.len());
let mut blocks = self.blocks.clone();
let mut prev_blockhash = blocks[height].block_hash();
for block in blocks.iter_mut().skip(height + 1) {
block.header.prev_blockhash = prev_blockhash;
block.header.nonce += 1;
prev_blockhash = block.block_hash();
}
Self { blocks, without_blocks: None, ..*self }
}
pub fn at_height(&self, height: usize) -> ValidatedBlockHeader {
let block_header = self.at_height_unvalidated(height);
let block_hash = self.blocks[height].block_hash();
block_header.validate(block_hash).unwrap()
}
fn at_height_unvalidated(&self, height: usize) -> BlockHeaderData {
assert!(!self.blocks.is_empty());
assert!(height < self.blocks.len());
BlockHeaderData {
chainwork: self.blocks[0].header.work() + Uint256::from_u64(height as u64).unwrap(),
height: height as u32,
header: self.blocks[height].header.clone(),
}
}
pub fn tip(&self) -> ValidatedBlockHeader {
assert!(!self.blocks.is_empty());
self.at_height(self.blocks.len() - 1)
}
pub fn disconnect_tip(&mut self) -> Option<Block> {
self.blocks.pop()
}
pub fn header_cache(&self, heights: std::ops::RangeInclusive<usize>) -> UnboundedCache {
let mut cache = UnboundedCache::new();
for i in heights {
let value = self.at_height(i);
let key = value.header.block_hash();
assert!(cache.insert(key, value).is_none());
}
cache
}
}
impl BlockSource for Blockchain {
fn get_header<'a>(&'a self, header_hash: &'a BlockHash, _height_hint: Option<u32>) -> AsyncBlockSourceResult<'a, BlockHeaderData> {
Box::pin(async move {
if self.without_headers {
return Err(BlockSourceError::persistent("header not found"));
}
for (height, block) in self.blocks.iter().enumerate() {
if block.header.block_hash() == *header_hash {
let mut header_data = self.at_height_unvalidated(height);
if self.malformed_headers {
header_data.header.time += 1;
}
return Ok(header_data);
}
}
Err(BlockSourceError::transient("header not found"))
})
}
fn get_block<'a>(&'a self, header_hash: &'a BlockHash) -> AsyncBlockSourceResult<'a, BlockData> {
Box::pin(async move {
for (height, block) in self.blocks.iter().enumerate() {
if block.header.block_hash() == *header_hash {
if let Some(without_blocks) = &self.without_blocks {
if without_blocks.contains(&height) {
return Err(BlockSourceError::persistent("block not found"));
}
}
if self.filtered_blocks {
return Ok(BlockData::HeaderOnly(block.header.clone()));
} else {
return Ok(BlockData::FullBlock(block.clone()));
}
}
}
Err(BlockSourceError::transient("block not found"))
})
}
fn get_best_block<'a>(&'a self) -> AsyncBlockSourceResult<'a, (BlockHash, Option<u32>)> {
Box::pin(async move {
match self.blocks.last() {
None => Err(BlockSourceError::transient("empty chain")),
Some(block) => {
let height = (self.blocks.len() - 1) as u32;
Ok((block.block_hash(), Some(height)))
},
}
})
}
}
pub struct NullChainListener;
impl chain::Listen for NullChainListener {
fn filtered_block_connected(&self, _header: &BlockHeader, _txdata: &chain::transaction::TransactionData, _height: u32) {}
fn block_disconnected(&self, _header: &BlockHeader, _height: u32) {}
}
pub struct MockChainListener {
expected_blocks_connected: RefCell<VecDeque<BlockHeaderData>>,
expected_filtered_blocks_connected: RefCell<VecDeque<BlockHeaderData>>,
expected_blocks_disconnected: RefCell<VecDeque<BlockHeaderData>>,
}
impl MockChainListener {
pub fn new() -> Self {
Self {
expected_blocks_connected: RefCell::new(VecDeque::new()),
expected_filtered_blocks_connected: RefCell::new(VecDeque::new()),
expected_blocks_disconnected: RefCell::new(VecDeque::new()),
}
}
pub fn expect_block_connected(self, block: BlockHeaderData) -> Self {
self.expected_blocks_connected.borrow_mut().push_back(block);
self
}
pub fn expect_filtered_block_connected(self, block: BlockHeaderData) -> Self {
self.expected_filtered_blocks_connected.borrow_mut().push_back(block);
self
}
pub fn expect_block_disconnected(self, block: BlockHeaderData) -> Self {
self.expected_blocks_disconnected.borrow_mut().push_back(block);
self
}
}
impl chain::Listen for MockChainListener {
fn block_connected(&self, block: &Block, height: u32) {
match self.expected_blocks_connected.borrow_mut().pop_front() {
None => {
panic!("Unexpected block connected: {:?}", block.block_hash());
},
Some(expected_block) => {
assert_eq!(block.block_hash(), expected_block.header.block_hash());
assert_eq!(height, expected_block.height);
},
}
}
fn filtered_block_connected(&self, header: &BlockHeader, _txdata: &chain::transaction::TransactionData, height: u32) {
match self.expected_filtered_blocks_connected.borrow_mut().pop_front() {
None => {
panic!("Unexpected filtered block connected: {:?}", header.block_hash());
},
Some(expected_block) => {
assert_eq!(header.block_hash(), expected_block.header.block_hash());
assert_eq!(height, expected_block.height);
},
}
}
fn block_disconnected(&self, header: &BlockHeader, height: u32) {
match self.expected_blocks_disconnected.borrow_mut().pop_front() {
None => {
panic!("Unexpected block disconnected: {:?}", header.block_hash());
},
Some(expected_block) => {
assert_eq!(header.block_hash(), expected_block.header.block_hash());
assert_eq!(height, expected_block.height);
},
}
}
}
impl Drop for MockChainListener {
fn drop(&mut self) {
if std::thread::panicking() {
return;
}
let expected_blocks_connected = self.expected_blocks_connected.borrow();
if !expected_blocks_connected.is_empty() {
panic!("Expected blocks connected: {:?}", expected_blocks_connected);
}
let expected_filtered_blocks_connected = self.expected_filtered_blocks_connected.borrow();
if !expected_filtered_blocks_connected.is_empty() {
panic!("Expected filtered_blocks connected: {:?}", expected_filtered_blocks_connected);
}
let expected_blocks_disconnected = self.expected_blocks_disconnected.borrow();
if !expected_blocks_disconnected.is_empty() {
panic!("Expected blocks disconnected: {:?}", expected_blocks_disconnected);
}
}
}