#!/usr/bin/env python # # Electrum - lightweight Bitcoin client # Copyright (C) 2014 Thomas Voegtlin # # Permission is hereby granted, free of charge, to any person # obtaining a copy of this software and associated documentation files # (the "Software"), to deal in the Software without restriction, # including without limitation the rights to use, copy, modify, merge, # publish, distribute, sublicense, and/or sell copies of the Software, # and to permit persons to whom the Software is furnished to do so, # subject to the following conditions: # # The above copyright notice and this permission notice shall be # included in all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS # BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN # ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE # SOFTWARE. import asyncio import hashlib from typing import Dict, List, TYPE_CHECKING, Tuple from collections import defaultdict import logging from aiorpcx import TaskGroup, run_in_thread, RPCError from .transaction import Transaction, PartialTransaction from .util import bh2u, make_aiohttp_session, NetworkJobOnDefaultServer from .bitcoin import address_to_scripthash, is_address from .network import UntrustedServerReturnedError from .logging import Logger from .interface import GracefulDisconnect if TYPE_CHECKING: from .network import Network from .address_synchronizer import AddressSynchronizer class SynchronizerFailure(Exception): pass def history_status(h): if not h: return None status = '' for tx_hash, height in h: status += tx_hash + ':%d:' % height return bh2u(hashlib.sha256(status.encode('ascii')).digest()) class SynchronizerBase(NetworkJobOnDefaultServer): """Subscribe over the network to a set of addresses, and monitor their statuses. Every time a status changes, run a coroutine provided by the subclass. """ def __init__(self, network: 'Network'): self.asyncio_loop = network.asyncio_loop self._reset_request_counters() NetworkJobOnDefaultServer.__init__(self, network) def _reset(self): super()._reset() self.requested_addrs = set() self.scripthash_to_address = {} self._processed_some_notifications = False # so that we don't miss them self._reset_request_counters() # Queues self.add_queue = asyncio.Queue() self.status_queue = asyncio.Queue() async def _start_tasks(self): try: async with self.group as group: await group.spawn(self.send_subscriptions()) await group.spawn(self.handle_status()) await group.spawn(self.main()) finally: # we are being cancelled now self.session.unsubscribe(self.status_queue) def _reset_request_counters(self): self._requests_sent = 0 self._requests_answered = 0 def add(self, addr): asyncio.run_coroutine_threadsafe(self._add_address(addr), self.asyncio_loop) async def _add_address(self, addr: str): if not is_address(addr): raise ValueError(f"invalid bitcoin address {addr}") if addr in self.requested_addrs: return self.requested_addrs.add(addr) await self.add_queue.put(addr) async def _on_address_status(self, addr, status): """Handle the change of the status of an address.""" raise NotImplementedError() # implemented by subclasses async def send_subscriptions(self): async def subscribe_to_address(addr): h = address_to_scripthash(addr) self.scripthash_to_address[h] = addr self._requests_sent += 1 try: await self.session.subscribe('blockchain.scripthash.subscribe', [h], self.status_queue) except RPCError as e: if e.message == 'history too large': # no unique error code raise GracefulDisconnect(e, log_level=logging.ERROR) from e raise self._requests_answered += 1 self.requested_addrs.remove(addr) while True: addr = await self.add_queue.get() await self.group.spawn(subscribe_to_address, addr) async def handle_status(self): while True: h, status = await self.status_queue.get() addr = self.scripthash_to_address[h] await self.group.spawn(self._on_address_status, addr, status) self._processed_some_notifications = True def num_requests_sent_and_answered(self) -> Tuple[int, int]: return self._requests_sent, self._requests_answered async def main(self): raise NotImplementedError() # implemented by subclasses class Synchronizer(SynchronizerBase): '''The synchronizer keeps the wallet up-to-date with its set of addresses and their transactions. It subscribes over the network to wallet addresses, gets the wallet to generate new addresses when necessary, requests the transaction history of any addresses we don't have the full history of, and requests binary transaction data of any transactions the wallet doesn't have. ''' def __init__(self, wallet: 'AddressSynchronizer'): self.wallet = wallet SynchronizerBase.__init__(self, wallet.network) def _reset(self): super()._reset() self.requested_tx = {} self.requested_histories = set() def diagnostic_name(self): return self.wallet.diagnostic_name() def is_up_to_date(self): return (not self.requested_addrs and not self.requested_histories and not self.requested_tx) async def _on_address_status(self, addr, status): history = self.wallet.db.get_addr_history(addr) if history_status(history) == status: return if (addr, status) in self.requested_histories: return # request address history self.requested_histories.add((addr, status)) h = address_to_scripthash(addr) self._requests_sent += 1 result = await self.network.get_history_for_scripthash(h) self._requests_answered += 1 self.logger.info(f"receiving history {addr} {len(result)}") hashes = set(map(lambda item: item['tx_hash'], result)) hist = list(map(lambda item: (item['tx_hash'], item['height']), result)) # tx_fees tx_fees = [(item['tx_hash'], item.get('fee')) for item in result] tx_fees = dict(filter(lambda x:x[1] is not None, tx_fees)) # Check that txids are unique if len(hashes) != len(result): self.logger.info(f"error: server history has non-unique txids: {addr}") # Check that the status corresponds to what was announced elif history_status(hist) != status: self.logger.info(f"error: status mismatch: {addr}") else: # Store received history self.wallet.receive_history_callback(addr, hist, tx_fees) # Request transactions we don't have await self._request_missing_txs(hist) # Remove request; this allows up_to_date to be True self.requested_histories.discard((addr, status)) async def _request_missing_txs(self, hist, *, allow_server_not_finding_tx=False): # "hist" is a list of [tx_hash, tx_height] lists transaction_hashes = [] for tx_hash, tx_height in hist: if tx_hash in self.requested_tx: continue tx = self.wallet.db.get_transaction(tx_hash) if tx and not isinstance(tx, PartialTransaction): continue # already have complete tx transaction_hashes.append(tx_hash) self.requested_tx[tx_hash] = tx_height if not transaction_hashes: return async with TaskGroup() as group: for tx_hash in transaction_hashes: await group.spawn(self._get_transaction(tx_hash, allow_server_not_finding_tx=allow_server_not_finding_tx)) async def _get_transaction(self, tx_hash, *, allow_server_not_finding_tx=False): self._requests_sent += 1 try: raw_tx = await self.network.get_transaction(tx_hash) except UntrustedServerReturnedError as e: # most likely, "No such mempool or blockchain transaction" if allow_server_not_finding_tx: self.requested_tx.pop(tx_hash) return else: raise finally: self._requests_answered += 1 tx = Transaction(raw_tx) if tx_hash != tx.txid(): raise SynchronizerFailure(f"received tx does not match expected txid ({tx_hash} != {tx.txid()})") tx_height = self.requested_tx.pop(tx_hash) self.wallet.receive_tx_callback(tx_hash, tx, tx_height) self.logger.info(f"received tx {tx_hash} height: {tx_height} bytes: {len(raw_tx)}") # callbacks self.wallet.network.trigger_callback('new_transaction', self.wallet, tx) async def main(self): self.wallet.set_up_to_date(False) # request missing txns, if any for addr in self.wallet.db.get_history(): history = self.wallet.db.get_addr_history(addr) # Old electrum servers returned ['*'] when all history for the address # was pruned. This no longer happens but may remain in old wallets. if history == ['*']: continue await self._request_missing_txs(history, allow_server_not_finding_tx=True) # add addresses to bootstrap for addr in self.wallet.get_addresses(): await self._add_address(addr) # main loop while True: await asyncio.sleep(0.1) await run_in_thread(self.wallet.synchronize) up_to_date = self.is_up_to_date() if (up_to_date != self.wallet.is_up_to_date() or up_to_date and self._processed_some_notifications): self._processed_some_notifications = False if up_to_date: self._reset_request_counters() self.wallet.set_up_to_date(up_to_date) self.wallet.network.trigger_callback('wallet_updated', self.wallet) class Notifier(SynchronizerBase): """Watch addresses. Every time the status of an address changes, an HTTP POST is sent to the corresponding URL. """ def __init__(self, network): SynchronizerBase.__init__(self, network) self.watched_addresses = defaultdict(list) # type: Dict[str, List[str]] self.start_watching_queue = asyncio.Queue() async def main(self): # resend existing subscriptions if we were restarted for addr in self.watched_addresses: await self._add_address(addr) # main loop while True: addr, url = await self.start_watching_queue.get() self.watched_addresses[addr].append(url) await self._add_address(addr) async def _on_address_status(self, addr, status): self.logger.info(f'new status for addr {addr}') headers = {'content-type': 'application/json'} data = {'address': addr, 'status': status} for url in self.watched_addresses[addr]: try: async with make_aiohttp_session(proxy=self.network.proxy, headers=headers) as session: async with session.post(url, json=data, headers=headers) as resp: await resp.text() except Exception as e: self.logger.info(repr(e)) else: self.logger.info(f'Got Response for {addr}')