import json import socket import logging from itertools import cycle from twisted.internet import defer, reactor, protocol from twisted.application.internet import ClientService, CancelledError from twisted.internet.endpoints import clientFromString from twisted.protocols.basic import LineOnlyReceiver from torba import __version__ from torba.stream import StreamController log = logging.getLogger(__name__) class StratumClientProtocol(LineOnlyReceiver): delimiter = b'\n' MAX_LENGTH = 2000000 def __init__(self): self.request_id = 0 self.lookup_table = {} self.session = {} self.network = None self.on_disconnected_controller = StreamController() self.on_disconnected = self.on_disconnected_controller.stream def _get_id(self): self.request_id += 1 return self.request_id @property def _ip(self): return self.transport.getPeer().host def get_session(self): return self.session def connectionMade(self): try: self.transport.setTcpNoDelay(True) self.transport.setTcpKeepAlive(True) self.transport.socket.setsockopt( socket.SOL_TCP, socket.TCP_KEEPIDLE, 120 # Seconds before sending keepalive probes ) self.transport.socket.setsockopt( socket.SOL_TCP, socket.TCP_KEEPINTVL, 1 # Interval in seconds between keepalive probes ) self.transport.socket.setsockopt( socket.SOL_TCP, socket.TCP_KEEPCNT, 5 # Failed keepalive probles before declaring other end dead ) except Exception as err: # pylint: disable=broad-except # Supported only by the socket transport, # but there's really no better place in code to trigger this. log.warning("Error setting up socket: %s", err) def connectionLost(self, reason=None): self.on_disconnected_controller.add(True) def lineReceived(self, line): log.debug('received: %s', line) try: message = json.loads(line) except (ValueError, TypeError): raise ValueError("Cannot decode message '{}'".format(line.strip())) if message.get('id'): try: d = self.lookup_table.pop(message['id']) if message.get('error'): d.errback(RuntimeError(message['error'])) else: d.callback(message.get('result')) except KeyError: raise LookupError( "Lookup for deferred object for message ID '{}' failed.".format(message['id'])) elif message.get('method') in self.network.subscription_controllers: controller = self.network.subscription_controllers[message['method']] controller.add(message.get('params')) else: log.warning("Cannot handle message '%s'", line) def rpc(self, method, *args): message_id = self._get_id() message = json.dumps({ 'id': message_id, 'method': method, 'params': args }) log.debug('sent: %s', message) self.sendLine(message.encode('latin-1')) d = self.lookup_table[message_id] = defer.Deferred() return d class StratumClientFactory(protocol.ClientFactory): protocol = StratumClientProtocol def __init__(self, network): self.network = network self.client = None def buildProtocol(self, addr): client = self.protocol() client.factory = self client.network = self.network self.client = client return client class BaseNetwork: def __init__(self, ledger): self.config = ledger.config self.client = None self.service = None self.running = False self._on_connected_controller = StreamController() self.on_connected = self._on_connected_controller.stream self._on_header_controller = StreamController() self.on_header = self._on_header_controller.stream self._on_status_controller = StreamController() self.on_status = self._on_status_controller.stream self.subscription_controllers = { 'blockchain.headers.subscribe': self._on_header_controller, 'blockchain.address.subscribe': self._on_status_controller, } @defer.inlineCallbacks def start(self): for server in cycle(self.config['default_servers']): connection_string = 'tcp:{}:{}'.format(*server) endpoint = clientFromString(reactor, connection_string) log.debug("Attempting connection to SPV wallet server: %s", connection_string) self.service = ClientService(endpoint, StratumClientFactory(self)) self.service.startService() try: self.client = yield self.service.whenConnected(failAfterFailures=2) yield self.ensure_server_version() log.info("Successfully connected to SPV wallet server: %s", connection_string) self._on_connected_controller.add(True) yield self.client.on_disconnected.first except CancelledError: return except Exception: # pylint: disable=broad-except log.exception("Connecting to %s raised an exception:", connection_string) finally: self.client = None if not self.running: return def stop(self): self.running = False if self.service is not None: self.service.stopService() if self.is_connected: return self.client.on_disconnected.first else: return defer.succeed(True) @property def is_connected(self): return self.client is not None and self.client.connected def rpc(self, list_or_method, *args): if self.is_connected: return self.client.rpc(list_or_method, *args) else: raise ConnectionError("Attempting to send rpc request when connection is not available.") def ensure_server_version(self, required='1.2'): return self.rpc('server.version', __version__, required) def broadcast(self, raw_transaction): return self.rpc('blockchain.transaction.broadcast', raw_transaction) def get_history(self, address): return self.rpc('blockchain.address.get_history', address) def get_transaction(self, tx_hash): return self.rpc('blockchain.transaction.get', tx_hash) def get_merkle(self, tx_hash, height): return self.rpc('blockchain.transaction.get_merkle', tx_hash, height) def get_headers(self, height, count=10000): return self.rpc('blockchain.block.headers', height, count) def subscribe_headers(self): return self.rpc('blockchain.headers.subscribe', True) def subscribe_address(self, address): return self.rpc('blockchain.address.subscribe', address)