#!/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 aiorpcx import TaskGroup from .transaction import Transaction from .util import bh2u, PrintError from .bitcoin import address_to_scripthash 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 Synchronizer(PrintError): '''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): self.wallet = wallet self.requested_tx = {} self.requested_histories = {} self.requested_addrs = set() self.scripthash_to_address = {} # Queues self.add_queue = asyncio.Queue() self.status_queue = asyncio.Queue() def diagnostic_name(self): return '{}:{}'.format(self.__class__.__name__, 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) def add(self, addr): self.requested_addrs.add(addr) self.add_queue.put_nowait(addr) async def on_address_status(self, addr, status): history = self.wallet.history.get(addr, []) if history_status(history) == status: return if addr in self.requested_histories: return # request address history self.requested_histories[addr] = status h = address_to_scripthash(addr) result = await self.session.send_request("blockchain.scripthash.get_history", [h]) self.print_error("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.print_error("error: server history has non-unique txids: %s"% addr) # Check that the status corresponds to what was announced elif history_status(hist) != status: self.print_error("error: status mismatch: %s" % 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.pop(addr) async def request_missing_txs(self, hist): # "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 if tx_hash in self.wallet.transactions: continue transaction_hashes.append(tx_hash) self.requested_tx[tx_hash] = tx_height async with TaskGroup() as group: for tx_hash in transaction_hashes: await group.spawn(self.get_transaction, tx_hash) async def get_transaction(self, tx_hash): result = await self.session.send_request('blockchain.transaction.get', [tx_hash]) tx = Transaction(result) try: tx.deserialize() except Exception: self.print_msg("cannot deserialize transaction, skipping", tx_hash) return if tx_hash != tx.txid(): self.print_error("received tx does not match expected txid ({} != {})" .format(tx_hash, tx.txid())) return tx_height = self.requested_tx.pop(tx_hash) self.wallet.receive_tx_callback(tx_hash, tx, tx_height) self.print_error("received tx %s height: %d bytes: %d" % (tx_hash, tx_height, len(tx.raw))) # callbacks self.wallet.network.trigger_callback('new_transaction', self.wallet, tx) async def subscribe_to_address(self, addr): h = address_to_scripthash(addr) self.scripthash_to_address[h] = addr await self.session.subscribe('blockchain.scripthash.subscribe', [h], self.status_queue) self.requested_addrs.remove(addr) async def send_subscriptions(self, group: TaskGroup): while True: addr = await self.add_queue.get() await group.spawn(self.subscribe_to_address, addr) async def handle_status(self, group: TaskGroup): while True: h, status = await self.status_queue.get() addr = self.scripthash_to_address[h] await group.spawn(self.on_address_status, addr, status) @property def session(self): s = self.wallet.network.interface.session assert s is not None return s async def main(self): self.wallet.set_up_to_date(False) # request missing txns, if any async with TaskGroup() as group: for history in self.wallet.history.values(): # 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 group.spawn(self.request_missing_txs, history) # add addresses to bootstrap for addr in self.wallet.get_addresses(): self.add(addr) # main loop while True: await asyncio.sleep(0.1) self.wallet.synchronize() up_to_date = self.is_up_to_date() if up_to_date != self.wallet.is_up_to_date(): self.wallet.set_up_to_date(up_to_date) self.wallet.network.trigger_callback('wallet_updated', self.wallet)