# Copyright (c) 2016, Neil Booth
# Copyright (c) 2017, the ElectrumX authors
#
# All rights reserved.
#
# See the file "LICENCE" for information about the copyright
# and warranty status of this software.
"""Interface to the blockchain database."""
import asyncio
import array
import ast
import base64
import os
import time
import zlib
import typing
from typing import Optional, List, Tuple, Iterable
from functools import partial
from asyncio import sleep
from bisect import bisect_right, bisect_left
from collections import namedtuple, defaultdict
from glob import glob
from struct import pack, unpack
from concurrent.futures.thread import ThreadPoolExecutor
import attr
from lbry.utils import LRUCacheWithMetrics
from lbry.wallet.server import util
from lbry.wallet.server.hash import hash_to_hex_str, HASHX_LEN
from lbry.wallet.server.merkle import Merkle, MerkleCache
from lbry.wallet.server.util import formatted_time, pack_be_uint16, unpack_be_uint16_from
from lbry.wallet.server.storage import db_class
UTXO = namedtuple("UTXO", "tx_num tx_pos tx_hash height value")
HISTORY_PREFIX = b'A'
TX_PREFIX = b'B'
BLOCK_HASH_PREFIX = b'C'
HEADER_PREFIX = b'H'
TX_NUM_PREFIX = b'N'
TX_COUNT_PREFIX = b'T'
UNDO_PREFIX = b'U'
TX_HASH_PREFIX = b'X'
HASHX_UTXO_PREFIX = b'h'
HIST_STATE = b'state-hist'
UTXO_STATE = b'state-utxo'
UTXO_PREFIX = b'u'
HASHX_HISTORY_PREFIX = b'x'
@attr.s(slots=True)
class FlushData:
height = attr.ib()
tx_count = attr.ib()
headers = attr.ib()
block_hashes = attr.ib()
block_txs = attr.ib()
# The following are flushed to the UTXO DB if undo_infos is not None
undo_infos = attr.ib()
adds = attr.ib()
deletes = attr.ib()
tip = attr.ib()
class LevelDB:
"""Simple wrapper of the backend database for querying.
Performs no DB update, though the DB will be cleaned on opening if
it was shutdown uncleanly.
"""
DB_VERSIONS = [6]
HIST_DB_VERSIONS = [0]
class DBError(Exception):
"""Raised on general DB errors generally indicating corruption."""
def __init__(self, env):
self.logger = util.class_logger(__name__, self.__class__.__name__)
self.env = env
self.coin = env.coin
self.executor = None
self.logger.info(f'switching current directory to {env.db_dir}')
self.db_class = db_class(env.db_dir, self.env.db_engine)
self.db = None
self.hist_unflushed = defaultdict(partial(array.array, 'I'))
self.hist_unflushed_count = 0
self.hist_flush_count = 0
self.hist_comp_flush_count = -1
self.hist_comp_cursor = -1
self.tx_counts = None
self.headers = None
self.encoded_headers = LRUCacheWithMetrics(1 << 21, metric_name='encoded_headers', namespace='wallet_server')
self.last_flush = time.time()
self.logger.info(f'using {self.env.db_engine} for DB backend')
# Header merkle cache
self.merkle = Merkle()
self.header_mc = MerkleCache(self.merkle, self.fs_block_hashes)
self.headers_db = None
self.tx_db = None
self._tx_and_merkle_cache = LRUCacheWithMetrics(2 ** 17, metric_name='tx_and_merkle', namespace="wallet_server")
self.total_transactions = None
# def add_unflushed(self, hashXs_by_tx, first_tx_num):
# unflushed = self.history.unflushed
# count = 0
# for tx_num, hashXs in enumerate(hashXs_by_tx, start=first_tx_num):
# hashXs = set(hashXs)
# for hashX in hashXs:
# unflushed[hashX].append(tx_num)
# count += len(hashXs)
# self.history.unflushed_count += count
# def unflushed_memsize(self):
# return len(self.history.unflushed) * 180 + self.history.unflushed_count * 4
async def _read_tx_counts(self):
if self.tx_counts is not None:
return
# tx_counts[N] has the cumulative number of txs at the end of
# height N. So tx_counts[0] is 1 - the genesis coinbase
def get_counts():
return tuple(
util.unpack_be_uint64(tx_count)
for tx_count in self.db.iterator(prefix=TX_COUNT_PREFIX, include_key=False)
)
tx_counts = await asyncio.get_event_loop().run_in_executor(self.executor, get_counts)
assert len(tx_counts) == self.db_height + 1, f"{len(tx_counts)} vs {self.db_height + 1}"
self.tx_counts = array.array('I', tx_counts)
if self.tx_counts:
assert self.db_tx_count == self.tx_counts[-1], \
f"{self.db_tx_count} vs {self.tx_counts[-1]} ({len(self.tx_counts)} counts)"
else:
assert self.db_tx_count == 0
async def _read_txids(self):
def get_txids():
return list(self.db.iterator(prefix=TX_HASH_PREFIX, include_key=False))
start = time.perf_counter()
self.logger.info("loading txids")
txids = await asyncio.get_event_loop().run_in_executor(self.executor, get_txids)
assert len(txids) == len(self.tx_counts) == 0 or len(txids) == self.tx_counts[-1]
self.total_transactions = txids
ts = time.perf_counter() - start
self.logger.info("loaded %i txids in %ss", len(self.total_transactions), round(ts, 4))
async def _read_headers(self):
if self.headers is not None:
return
def get_headers():
return [
header for header in self.db.iterator(prefix=HEADER_PREFIX, include_key=False)
]
headers = await asyncio.get_event_loop().run_in_executor(self.executor, get_headers)
assert len(headers) - 1 == self.db_height, f"{len(headers)} vs {self.db_height}"
self.headers = headers
async def _open_dbs(self, for_sync, compacting):
if self.executor is None:
self.executor = ThreadPoolExecutor(1)
coin_path = os.path.join(self.env.db_dir, 'COIN')
if not os.path.isfile(coin_path):
with util.open_file(coin_path, create=True) as f:
f.write(f'ElectrumX databases and metadata for '
f'{self.coin.NAME} {self.coin.NET}'.encode())
assert self.db is None
self.db = self.db_class(f'lbry-{self.env.db_engine}', for_sync)
if self.db.is_new:
self.logger.info('created new db: %s', f'lbry-{self.env.db_engine}')
self.logger.info(f'opened DB (for sync: {for_sync})')
self.read_utxo_state()
# Then history DB
state = self.db.get(HIST_STATE)
if state:
state = ast.literal_eval(state.decode())
if not isinstance(state, dict):
raise RuntimeError('failed reading state from history DB')
self.hist_flush_count = state['flush_count']
self.hist_comp_flush_count = state.get('comp_flush_count', -1)
self.hist_comp_cursor = state.get('comp_cursor', -1)
self.hist_db_version = state.get('db_version', 0)
else:
self.hist_flush_count = 0
self.hist_comp_flush_count = -1
self.hist_comp_cursor = -1
self.hist_db_version = max(self.HIST_DB_VERSIONS)
self.logger.info(f'history DB version: {self.hist_db_version}')
if self.hist_db_version not in self.HIST_DB_VERSIONS:
msg = f'this software only handles DB versions {self.HIST_DB_VERSIONS}'
self.logger.error(msg)
raise RuntimeError(msg)
self.logger.info(f'flush count: {self.hist_flush_count:,d}')
# self.history.clear_excess(self.utxo_flush_count)
# < might happen at end of compaction as both DBs cannot be
# updated atomically
if self.hist_flush_count > self.utxo_flush_count:
self.logger.info('DB shut down uncleanly. Scanning for '
'excess history flushes...')
keys = []
for key, hist in self.db.iterator(prefix=HASHX_HISTORY_PREFIX):
k = key[1:]
flush_id, = unpack_be_uint16_from(k[-2:])
if flush_id > self.utxo_flush_count:
keys.append(k)
self.logger.info(f'deleting {len(keys):,d} history entries')
self.hist_flush_count = self.utxo_flush_count
with self.db.write_batch() as batch:
for key in keys:
batch.delete(HASHX_HISTORY_PREFIX + key)
state = {
'flush_count': self.hist_flush_count,
'comp_flush_count': self.hist_comp_flush_count,
'comp_cursor': self.hist_comp_cursor,
'db_version': self.hist_db_version,
}
# History entries are not prefixed; the suffix \0\0 ensures we
# look similar to other entries and aren't interfered with
batch.put(HIST_STATE, repr(state).encode())
self.logger.info('deleted excess history entries')
self.utxo_flush_count = self.hist_flush_count
min_height = self.min_undo_height(self.db_height)
keys = []
for key, hist in self.db.iterator(prefix=UNDO_PREFIX):
height, = unpack('>I', key[-4:])
if height >= min_height:
break
keys.append(key)
if keys:
with self.db.write_batch() as batch:
for key in keys:
batch.delete(key)
self.logger.info(f'deleted {len(keys):,d} stale undo entries')
# delete old block files
prefix = self.raw_block_prefix()
paths = [path for path in glob(f'{prefix}[0-9]*')
if len(path) > len(prefix)
and int(path[len(prefix):]) < min_height]
if paths:
for path in paths:
try:
os.remove(path)
except FileNotFoundError:
pass
self.logger.info(f'deleted {len(paths):,d} stale block files')
# Read TX counts (requires meta directory)
await self._read_tx_counts()
if self.total_transactions is None:
await self._read_txids()
await self._read_headers()
def close(self):
self.db.close()
self.executor.shutdown(wait=True)
self.executor = None
async def open_for_compacting(self):
await self._open_dbs(True, True)
async def open_for_sync(self):
"""Open the databases to sync to the daemon.
When syncing we want to reserve a lot of open files for the
synchronization. When serving clients we want the open files for
serving network connections.
"""
self.logger.info("opened for sync")
await self._open_dbs(True, False)
async def open_for_serving(self):
"""Open the databases for serving. If they are already open they are
closed first.
"""
if self.db:
return
# self.logger.info('closing DBs to re-open for serving')
# self.db.close()
# self.history.close_db()
# self.db = None
await self._open_dbs(False, False)
self.logger.info("opened for serving")
# Header merkle cache
async def populate_header_merkle_cache(self):
self.logger.info('populating header merkle cache...')
length = max(1, self.db_height - self.env.reorg_limit)
start = time.time()
await self.header_mc.initialize(length)
elapsed = time.time() - start
self.logger.info(f'header merkle cache populated in {elapsed:.1f}s')
async def header_branch_and_root(self, length, height):
return await self.header_mc.branch_and_root(length, height)
# Flushing
def assert_flushed(self, flush_data):
"""Asserts state is fully flushed."""
assert flush_data.tx_count == self.fs_tx_count == self.db_tx_count
assert flush_data.height == self.fs_height == self.db_height
assert flush_data.tip == self.db_tip
assert not flush_data.headers
assert not flush_data.block_txs
assert not flush_data.adds
assert not flush_data.deletes
assert not flush_data.undo_infos
assert not self.hist_unflushed
def flush_utxo_db(self, batch, flush_data):
"""Flush the cached DB writes and UTXO set to the batch."""
# Care is needed because the writes generated by flushing the
# UTXO state may have keys in common with our write cache or
# may be in the DB already.
start_time = time.time()
add_count = len(flush_data.adds)
spend_count = len(flush_data.deletes) // 2
# Spends
batch_delete = batch.delete
for key in sorted(flush_data.deletes):
batch_delete(key)
flush_data.deletes.clear()
# New UTXOs
batch_put = batch.put
for key, value in flush_data.adds.items():
# suffix = tx_idx + tx_num
hashX = value[:-12]
suffix = key[-2:] + value[-12:-8]
batch_put(HASHX_UTXO_PREFIX + key[:4] + suffix, hashX)
batch_put(UTXO_PREFIX + hashX + suffix, value[-8:])
flush_data.adds.clear()
# New undo information
for undo_info, height in flush_data.undo_infos:
batch_put(self.undo_key(height), b''.join(undo_info))
flush_data.undo_infos.clear()
if self.db.for_sync:
block_count = flush_data.height - self.db_height
tx_count = flush_data.tx_count - self.db_tx_count
elapsed = time.time() - start_time
self.logger.info(f'flushed {block_count:,d} blocks with '
f'{tx_count:,d} txs, {add_count:,d} UTXO adds, '
f'{spend_count:,d} spends in '
f'{elapsed:.1f}s, committing...')
self.utxo_flush_count = self.hist_flush_count
self.db_height = flush_data.height
self.db_tx_count = flush_data.tx_count
self.db_tip = flush_data.tip
def write_history_state(self, batch):
state = {
'flush_count': self.hist_flush_count,
'comp_flush_count': self.hist_comp_flush_count,
'comp_cursor': self.hist_comp_cursor,
'db_version': self.db_version,
}
# History entries are not prefixed; the suffix \0\0 ensures we
# look similar to other entries and aren't interfered with
batch.put(HIST_STATE, repr(state).encode())
def flush_dbs(self, flush_data: FlushData, estimate_txs_remaining):
"""Flush out cached state. History is always flushed; UTXOs are
flushed if flush_utxos."""
if flush_data.height == self.db_height:
self.assert_flushed(flush_data)
return
start_time = time.time()
prior_flush = self.last_flush
tx_delta = flush_data.tx_count - self.last_flush_tx_count
# Flush to file system
# self.flush_fs(flush_data)
prior_tx_count = (self.tx_counts[self.fs_height]
if self.fs_height >= 0 else 0)
assert len(flush_data.block_txs) == len(flush_data.headers)
assert flush_data.height == self.fs_height + len(flush_data.headers)
assert flush_data.tx_count == (self.tx_counts[-1] if self.tx_counts
else 0)
assert len(self.tx_counts) == flush_data.height + 1
assert len(
b''.join(hashes for hashes, _ in flush_data.block_txs)
) // 32 == flush_data.tx_count - prior_tx_count
# Write the headers
start_time = time.perf_counter()
with self.db.write_batch() as batch:
batch_put = batch.put
height_start = self.fs_height + 1
tx_num = prior_tx_count
for i, (header, block_hash, (tx_hashes, txs)) in enumerate(zip(flush_data.headers, flush_data.block_hashes, flush_data.block_txs)):
batch_put(HEADER_PREFIX + util.pack_be_uint64(height_start), header)
self.headers.append(header)
tx_count = self.tx_counts[height_start]
batch_put(BLOCK_HASH_PREFIX + util.pack_be_uint64(height_start), block_hash[::-1])
batch_put(TX_COUNT_PREFIX + util.pack_be_uint64(height_start), util.pack_be_uint64(tx_count))
height_start += 1
offset = 0
while offset < len(tx_hashes):
batch_put(TX_HASH_PREFIX + util.pack_be_uint64(tx_num), tx_hashes[offset:offset + 32])
batch_put(TX_NUM_PREFIX + tx_hashes[offset:offset + 32], util.pack_be_uint64(tx_num))
batch_put(TX_PREFIX + tx_hashes[offset:offset + 32], txs[offset // 32])
tx_num += 1
offset += 32
flush_data.headers.clear()
flush_data.block_txs.clear()
flush_data.block_hashes.clear()
# flush_data.claim_txo_cache.clear()
# flush_data.support_txo_cache.clear()
self.fs_height = flush_data.height
self.fs_tx_count = flush_data.tx_count
# Then history
self.hist_flush_count += 1
flush_id = pack_be_uint16(self.hist_flush_count)
unflushed = self.hist_unflushed
for hashX in sorted(unflushed):
key = hashX + flush_id
batch_put(HASHX_HISTORY_PREFIX + key, unflushed[hashX].tobytes())
self.write_history_state(batch)
unflushed.clear()
self.hist_unflushed_count = 0
#########################
# Flush state last as it reads the wall time.
self.flush_utxo_db(batch, flush_data)
# self.flush_state(batch)
#
now = time.time()
self.wall_time += now - self.last_flush
self.last_flush = now
self.last_flush_tx_count = self.fs_tx_count
self.write_utxo_state(batch)
# # Update and put the wall time again - otherwise we drop the
# # time it took to commit the batch
# # self.flush_state(self.db)
# now = time.time()
# self.wall_time += now - self.last_flush
# self.last_flush = now
# self.last_flush_tx_count = self.fs_tx_count
# self.write_utxo_state(batch)
elapsed = self.last_flush - start_time
self.logger.info(f'flush #{self.hist_flush_count:,d} took '
f'{elapsed:.1f}s. Height {flush_data.height:,d} '
f'txs: {flush_data.tx_count:,d} ({tx_delta:+,d})')
# Catch-up stats
if self.db.for_sync:
flush_interval = self.last_flush - prior_flush
tx_per_sec_gen = int(flush_data.tx_count / self.wall_time)
tx_per_sec_last = 1 + int(tx_delta / flush_interval)
eta = estimate_txs_remaining() / tx_per_sec_last
self.logger.info(f'tx/sec since genesis: {tx_per_sec_gen:,d}, '
f'since last flush: {tx_per_sec_last:,d}')
self.logger.info(f'sync time: {formatted_time(self.wall_time)} '
f'ETA: {formatted_time(eta)}')
# def flush_state(self, batch):
# """Flush chain state to the batch."""
# now = time.time()
# self.wall_time += now - self.last_flush
# self.last_flush = now
# self.last_flush_tx_count = self.fs_tx_count
# self.write_utxo_state(batch)
def flush_backup(self, flush_data, touched):
"""Like flush_dbs() but when backing up. All UTXOs are flushed."""
assert not flush_data.headers
assert not flush_data.block_txs
assert flush_data.height < self.db_height
assert not self.hist_unflushed
start_time = time.time()
tx_delta = flush_data.tx_count - self.last_flush_tx_count
###
while self.fs_height > flush_data.height:
self.fs_height -= 1
self.headers.pop()
self.fs_tx_count = flush_data.tx_count
# Truncate header_mc: header count is 1 more than the height.
self.header_mc.truncate(flush_data.height + 1)
###
# Not certain this is needed, but it doesn't hurt
self.hist_flush_count += 1
nremoves = 0
with self.db.write_batch() as batch:
tx_count = flush_data.tx_count
for hashX in sorted(touched):
deletes = []
puts = {}
for key, hist in self.db.iterator(prefix=HASHX_HISTORY_PREFIX + hashX, reverse=True):
k = key[1:]
a = array.array('I')
a.frombytes(hist)
# Remove all history entries >= tx_count
idx = bisect_left(a, tx_count)
nremoves += len(a) - idx
if idx > 0:
puts[k] = a[:idx].tobytes()
break
deletes.append(k)
for key in deletes:
batch.delete(key)
for key, value in puts.items():
batch.put(key, value)
self.write_history_state(batch)
self.flush_utxo_db(batch, flush_data)
# Flush state last as it reads the wall time.
now = time.time()
self.wall_time += now - self.last_flush
self.last_flush = now
self.last_flush_tx_count = self.fs_tx_count
self.write_utxo_state(batch)
self.logger.info(f'backing up removed {nremoves:,d} history entries')
elapsed = self.last_flush - start_time
self.logger.info(f'backup flush #{self.hist_flush_count:,d} took {elapsed:.1f}s. '
f'Height {flush_data.height:,d} txs: {flush_data.tx_count:,d} ({tx_delta:+,d})')
def raw_header(self, height):
"""Return the binary header at the given height."""
header, n = self.read_headers(height, 1)
if n != 1:
raise IndexError(f'height {height:,d} out of range')
return header
def encode_headers(self, start_height, count, headers):
key = (start_height, count)
if not self.encoded_headers.get(key):
compressobj = zlib.compressobj(wbits=-15, level=1, memLevel=9)
headers = base64.b64encode(compressobj.compress(headers) + compressobj.flush()).decode()
if start_height % 1000 != 0:
return headers
self.encoded_headers[key] = headers
return self.encoded_headers.get(key)
def read_headers(self, start_height, count) -> typing.Tuple[bytes, int]:
"""Requires start_height >= 0, count >= 0. Reads as many headers as
are available starting at start_height up to count. This
would be zero if start_height is beyond self.db_height, for
example.
Returns a (binary, n) pair where binary is the concatenated
binary headers, and n is the count of headers returned.
"""
if start_height < 0 or count < 0:
raise self.DBError(f'{count:,d} headers starting at '
f'{start_height:,d} not on disk')
disk_count = max(0, min(count, self.db_height + 1 - start_height))
if disk_count:
return b''.join(self.headers[start_height:start_height + disk_count]), disk_count
return b'', 0
def fs_tx_hash(self, tx_num):
"""Return a par (tx_hash, tx_height) for the given tx number.
If the tx_height is not on disk, returns (None, tx_height)."""
tx_height = bisect_right(self.tx_counts, tx_num)
if tx_height > self.db_height:
return None, tx_height
try:
return self.total_transactions[tx_num], tx_height
except IndexError:
self.logger.exception(
"Failed to access a cached transaction, known bug #3142 "
"should be fixed in #3205"
)
return None, tx_height
def _fs_transactions(self, txids: Iterable[str]):
unpack_be_uint64 = util.unpack_be_uint64
tx_counts = self.tx_counts
tx_db_get = self.db.get
tx_cache = self._tx_and_merkle_cache
tx_infos = {}
for tx_hash in txids:
cached_tx = tx_cache.get(tx_hash)
if cached_tx:
tx, merkle = cached_tx
else:
tx_hash_bytes = bytes.fromhex(tx_hash)[::-1]
tx_num = tx_db_get(TX_NUM_PREFIX + tx_hash_bytes)
tx = None
tx_height = -1
if tx_num is not None:
tx_num = unpack_be_uint64(tx_num)
tx_height = bisect_right(tx_counts, tx_num)
if tx_height < self.db_height:
tx = tx_db_get(TX_PREFIX + tx_hash_bytes)
if tx_height == -1:
merkle = {
'block_height': -1
}
else:
tx_pos = tx_num - tx_counts[tx_height - 1]
branch, root = self.merkle.branch_and_root(
self.total_transactions[tx_counts[tx_height - 1]:tx_counts[tx_height]], tx_pos
)
merkle = {
'block_height': tx_height,
'merkle': [
hash_to_hex_str(hash)
for hash in branch
],
'pos': tx_pos
}
if tx_height + 10 < self.db_height:
tx_cache[tx_hash] = tx, merkle
tx_infos[tx_hash] = (None if not tx else tx.hex(), merkle)
return tx_infos
async def fs_transactions(self, txids):
return await asyncio.get_event_loop().run_in_executor(self.executor, self._fs_transactions, txids)
async def fs_block_hashes(self, height, count):
if height + count > len(self.headers):
raise self.DBError(f'only got {len(self.headers) - height:,d} headers starting at {height:,d}, not {count:,d}')
return [self.coin.header_hash(header) for header in self.headers[height:height + count]]
async def limited_history(self, hashX, *, limit=1000):
"""Return an unpruned, sorted list of (tx_hash, height) tuples of
confirmed transactions that touched the address, earliest in
the blockchain first. Includes both spending and receiving
transactions. By default returns at most 1000 entries. Set
limit to None to get them all.
"""
def read_history():
db_height = self.db_height
tx_counts = self.tx_counts
tx_db_get = self.db.get
pack_be_uint64 = util.pack_be_uint64
cnt = 0
txs = []
for hist in self.db.iterator(prefix=HASHX_HISTORY_PREFIX + hashX, include_key=False):
a = array.array('I')
a.frombytes(hist)
for tx_num in a:
tx_height = bisect_right(tx_counts, tx_num)
if tx_height > db_height:
return
txs.append((tx_num, tx_height))
cnt += 1
if limit and cnt >= limit:
break
if limit and cnt >= limit:
break
return txs
while True:
history = await asyncio.get_event_loop().run_in_executor(self.executor, read_history)
if history is not None:
return [(self.total_transactions[tx_num], tx_height) for (tx_num, tx_height) in history]
self.logger.warning(f'limited_history: tx hash '
f'not found (reorg?), retrying...')
await sleep(0.25)
# -- Undo information
def min_undo_height(self, max_height):
"""Returns a height from which we should store undo info."""
return max_height - self.env.reorg_limit + 1
def undo_key(self, height):
"""DB key for undo information at the given height."""
return UNDO_PREFIX + pack('>I', height)
def read_undo_info(self, height):
"""Read undo information from a file for the current height."""
return self.db.get(self.undo_key(height))
def raw_block_prefix(self):
return 'block'
def raw_block_path(self, height):
return os.path.join(self.env.db_dir, f'{self.raw_block_prefix()}{height:d}')
async def read_raw_block(self, height):
"""Returns a raw block read from disk. Raises FileNotFoundError
if the block isn't on-disk."""
def read():
with util.open_file(self.raw_block_path(height)) as f:
return f.read(-1)
return await asyncio.get_event_loop().run_in_executor(self.executor, read)
def write_raw_block(self, block, height):
"""Write a raw block to disk."""
with util.open_truncate(self.raw_block_path(height)) as f:
f.write(block)
# Delete old blocks to prevent them accumulating
try:
del_height = self.min_undo_height(height) - 1
os.remove(self.raw_block_path(del_height))
except FileNotFoundError:
pass
def clear_excess_undo_info(self):
"""Clear excess undo info. Only most recent N are kept."""
min_height = self.min_undo_height(self.db_height)
keys = []
for key, hist in self.db.iterator(prefix=UNDO_PREFIX):
height, = unpack('>I', key[-4:])
if height >= min_height:
break
keys.append(key)
if keys:
with self.db.write_batch() as batch:
for key in keys:
batch.delete(key)
self.logger.info(f'deleted {len(keys):,d} stale undo entries')
# delete old block files
prefix = self.raw_block_prefix()
paths = [path for path in glob(f'{prefix}[0-9]*')
if len(path) > len(prefix)
and int(path[len(prefix):]) < min_height]
if paths:
for path in paths:
try:
os.remove(path)
except FileNotFoundError:
pass
self.logger.info(f'deleted {len(paths):,d} stale block files')
# -- UTXO database
def read_utxo_state(self):
state = self.db.get(UTXO_STATE)
if not state:
self.db_height = -1
self.db_tx_count = 0
self.db_tip = b'\0' * 32
self.db_version = max(self.DB_VERSIONS)
self.utxo_flush_count = 0
self.wall_time = 0
self.first_sync = True
else:
state = ast.literal_eval(state.decode())
if not isinstance(state, dict):
raise self.DBError('failed reading state from DB')
self.db_version = state['db_version']
if self.db_version not in self.DB_VERSIONS:
raise self.DBError(f'your UTXO DB version is {self.db_version} but this '
f'software only handles versions {self.DB_VERSIONS}')
# backwards compat
genesis_hash = state['genesis']
if isinstance(genesis_hash, bytes):
genesis_hash = genesis_hash.decode()
if genesis_hash != self.coin.GENESIS_HASH:
raise self.DBError(f'DB genesis hash {genesis_hash} does not '
f'match coin {self.coin.GENESIS_HASH}')
self.db_height = state['height']
self.db_tx_count = state['tx_count']
self.db_tip = state['tip']
self.utxo_flush_count = state['utxo_flush_count']
self.wall_time = state['wall_time']
self.first_sync = state['first_sync']
# These are our state as we move ahead of DB state
self.fs_height = self.db_height
self.fs_tx_count = self.db_tx_count
self.last_flush_tx_count = self.fs_tx_count
# Log some stats
self.logger.info(f'DB version: {self.db_version:d}')
self.logger.info(f'coin: {self.coin.NAME}')
self.logger.info(f'network: {self.coin.NET}')
self.logger.info(f'height: {self.db_height:,d}')
self.logger.info(f'tip: {hash_to_hex_str(self.db_tip)}')
self.logger.info(f'tx count: {self.db_tx_count:,d}')
if self.db.for_sync:
self.logger.info(f'flushing DB cache at {self.env.cache_MB:,d} MB')
if self.first_sync:
self.logger.info(f'sync time so far: {util.formatted_time(self.wall_time)}')
def write_utxo_state(self, batch):
"""Write (UTXO) state to the batch."""
state = {
'genesis': self.coin.GENESIS_HASH,
'height': self.db_height,
'tx_count': self.db_tx_count,
'tip': self.db_tip,
'utxo_flush_count': self.utxo_flush_count,
'wall_time': self.wall_time,
'first_sync': self.first_sync,
'db_version': self.db_version,
}
batch.put(UTXO_STATE, repr(state).encode())
def set_flush_count(self, count):
self.utxo_flush_count = count
with self.db.write_batch() as batch:
self.write_utxo_state(batch)
async def all_utxos(self, hashX):
"""Return all UTXOs for an address sorted in no particular order."""
def read_utxos():
utxos = []
utxos_append = utxos.append
s_unpack = unpack
fs_tx_hash = self.fs_tx_hash
# Key: b'u' + address_hashX + tx_idx + tx_num
# Value: the UTXO value as a 64-bit unsigned integer
prefix = UTXO_PREFIX + hashX
for db_key, db_value in self.db.iterator(prefix=prefix):
tx_pos, tx_num = s_unpack('<HI', db_key[-6:])
value, = unpack('<Q', db_value)
tx_hash, height = fs_tx_hash(tx_num)
utxos_append(UTXO(tx_num, tx_pos, tx_hash, height, value))
return utxos
while True:
utxos = await asyncio.get_event_loop().run_in_executor(self.executor, read_utxos)
if all(utxo.tx_hash is not None for utxo in utxos):
return utxos
self.logger.warning(f'all_utxos: tx hash not '
f'found (reorg?), retrying...')
await sleep(0.25)
async def lookup_utxos(self, prevouts):
"""For each prevout, lookup it up in the DB and return a (hashX,
value) pair or None if not found.
Used by the mempool code.
"""
def lookup_hashXs():
"""Return (hashX, suffix) pairs, or None if not found,
for each prevout.
"""
def lookup_hashX(tx_hash, tx_idx):
idx_packed = pack('<H', tx_idx)
# Key: b'h' + compressed_tx_hash + tx_idx + tx_num
# Value: hashX
prefix = HASHX_UTXO_PREFIX + tx_hash[:4] + idx_packed
# Find which entry, if any, the TX_HASH matches.
for db_key, hashX in self.db.iterator(prefix=prefix):
tx_num_packed = db_key[-4:]
tx_num, = unpack('<I', tx_num_packed)
hash, height = self.fs_tx_hash(tx_num)
if hash == tx_hash:
return hashX, idx_packed + tx_num_packed
return None, None
return [lookup_hashX(*prevout) for prevout in prevouts]
def lookup_utxos(hashX_pairs):
def lookup_utxo(hashX, suffix):
if not hashX:
# This can happen when the daemon is a block ahead
# of us and has mempool txs spending outputs from
# that new block
return None
# Key: b'u' + address_hashX + tx_idx + tx_num
# Value: the UTXO value as a 64-bit unsigned integer
key = UTXO_PREFIX + hashX + suffix
db_value = self.db.get(key)
if not db_value:
# This can happen if the DB was updated between
# getting the hashXs and getting the UTXOs
return None
value, = unpack('<Q', db_value)
return hashX, value
return [lookup_utxo(*hashX_pair) for hashX_pair in hashX_pairs]
hashX_pairs = await asyncio.get_event_loop().run_in_executor(self.executor, lookup_hashXs)
return await asyncio.get_event_loop().run_in_executor(self.executor, lookup_utxos, hashX_pairs)