def test_non_unique_events(self):
events = []
controller = StreamController()
controller.stream.listen(on_data=events.append)
controller.add("yo")
controller.add("yo")
self.assertListEqual(events, ["yo", "yo"])
def test_unique_events(self):
events = []
controller = StreamController(merge_repeated_events=True)
controller.stream.listen(on_data=events.append)
controller.add("yo")
controller.add("yo")
self.assertListEqual(events, ["yo"])
class Network:
PROTOCOL_VERSION = __version__
MINIMUM_REQUIRED = (0, 57, 0)
def __init__(self, ledger):
self.ledger = ledger
self.session_pool = SessionPool(network=self,
timeout=self.config.get(
'connect_timeout', 6))
self.client: Optional[ClientSession] = None
self._switch_task: Optional[asyncio.Task] = None
self.running = False
self.remote_height: int = 0
self._concurrency = asyncio.Semaphore(16)
self._on_connected_controller = StreamController()
self.on_connected = self._on_connected_controller.stream
self._on_header_controller = StreamController(
merge_repeated_events=True)
self.on_header = self._on_header_controller.stream
self._on_status_controller = StreamController(
merge_repeated_events=True)
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,
}
@property
def config(self):
return self.ledger.config
async def switch_forever(self):
while self.running:
if self.is_connected:
await self.client.on_disconnected.first
self.client = None
continue
self.client = await self.session_pool.wait_for_fastest_session()
log.info("Switching to SPV wallet server: %s:%d",
*self.client.server)
try:
self._update_remote_height((await self.subscribe_headers(), ))
self._on_connected_controller.add(True)
log.info("Subscribed to headers: %s:%d", *self.client.server)
except (asyncio.TimeoutError, ConnectionError):
log.info("Switching to %s:%d timed out, closing and retrying.",
*self.client.server)
self.client.synchronous_close()
self.client = None
async def start(self):
self.running = True
self._switch_task = asyncio.ensure_future(self.switch_forever())
# this may become unnecessary when there are no more bugs found,
# but for now it helps understanding log reports
self._switch_task.add_done_callback(
lambda _: log.info("Wallet client switching task stopped."))
self.session_pool.start(self.config['default_servers'])
self.on_header.listen(self._update_remote_height)
async def stop(self):
if self.running:
self.running = False
self._switch_task.cancel()
self.session_pool.stop()
@property
def is_connected(self):
return self.client and not self.client.is_closing()
def rpc(self, list_or_method, args, restricted=True):
session = self.client if restricted else self.session_pool.fastest_session
if session and not session.is_closing():
return session.send_request(list_or_method, args)
else:
self.session_pool.trigger_nodelay_connect()
raise ConnectionError(
"Attempting to send rpc request when connection is not available."
)
async def retriable_call(self, function, *args, **kwargs):
async with self._concurrency:
while self.running:
if not self.is_connected:
log.warning(
"Wallet server unavailable, waiting for it to come back and retry."
)
await self.on_connected.first
await self.session_pool.wait_for_fastest_session()
try:
return await function(*args, **kwargs)
except asyncio.TimeoutError:
log.warning("Wallet server call timed out, retrying.")
except ConnectionError:
pass
raise asyncio.CancelledError() # if we got here, we are shutting down
def _update_remote_height(self, header_args):
self.remote_height = header_args[0]["height"]
def get_transaction(self, tx_hash, known_height=None):
# use any server if its old, otherwise restrict to who gave us the history
restricted = known_height in (
None, -1, 0) or 0 > known_height > self.remote_height - 10
return self.rpc('blockchain.transaction.get', [tx_hash], restricted)
def get_transaction_height(self, tx_hash, known_height=None):
restricted = not known_height or 0 > known_height > self.remote_height - 10
return self.rpc('blockchain.transaction.get_height', [tx_hash],
restricted)
def get_merkle(self, tx_hash, height):
restricted = 0 > height > self.remote_height - 10
return self.rpc('blockchain.transaction.get_merkle', [tx_hash, height],
restricted)
def get_headers(self, height, count=10000, b64=False):
restricted = height >= self.remote_height - 100
return self.rpc('blockchain.block.headers', [height, count, 0, b64],
restricted)
# --- Subscribes, history and broadcasts are always aimed towards the master client directly
def get_history(self, address):
return self.rpc('blockchain.address.get_history', [address], True)
def broadcast(self, raw_transaction):
return self.rpc('blockchain.transaction.broadcast', [raw_transaction],
True)
def subscribe_headers(self):
return self.rpc('blockchain.headers.subscribe', [True], True)
async def subscribe_address(self, address, *addresses):
addresses = list((address, ) + addresses)
try:
return await self.rpc('blockchain.address.subscribe', addresses,
True)
except asyncio.TimeoutError:
log.warning("timed out subscribing to addresses from %s:%i",
*self.client.server_address_and_port)
# abort and cancel, we can't lose a subscription, it will happen again on reconnect
if self.client:
self.client.abort()
raise asyncio.CancelledError()
def unsubscribe_address(self, address):
return self.rpc('blockchain.address.unsubscribe', [address], True)
def get_server_features(self):
return self.rpc('server.features', (), restricted=True)
def get_claims_by_ids(self, claim_ids):
return self.rpc('blockchain.claimtrie.getclaimsbyids', claim_ids)
def resolve(self, urls):
return self.rpc('blockchain.claimtrie.resolve', urls)
def claim_search(self, **kwargs):
return self.rpc('blockchain.claimtrie.search', kwargs)
class ClientSession(BaseClientSession):
def __init__(self,
*args,
network,
server,
timeout=30,
on_connect_callback=None,
**kwargs):
self.network = network
self.server = server
super().__init__(*args, **kwargs)
self._on_disconnect_controller = StreamController()
self.on_disconnected = self._on_disconnect_controller.stream
self.framer.max_size = self.max_errors = 1 << 32
self.timeout = timeout
self.max_seconds_idle = timeout * 2
self.response_time: Optional[float] = None
self.connection_latency: Optional[float] = None
self._response_samples = 0
self.pending_amount = 0
self._on_connect_cb = on_connect_callback or (lambda: None)
self.trigger_urgent_reconnect = asyncio.Event()
@property
def available(self):
return not self.is_closing() and self.response_time is not None
@property
def server_address_and_port(self) -> Optional[Tuple[str, int]]:
if not self.transport:
return None
return self.transport.get_extra_info('peername')
async def send_timed_server_version_request(self, args=(), timeout=None):
timeout = timeout or self.timeout
log.debug("send version request to %s:%i", *self.server)
start = perf_counter()
result = await asyncio.wait_for(super().send_request(
'server.version', args),
timeout=timeout)
current_response_time = perf_counter() - start
response_sum = (self.response_time
or 0) * self._response_samples + current_response_time
self.response_time = response_sum / (self._response_samples + 1)
self._response_samples += 1
return result
async def send_request(self, method, args=()):
self.pending_amount += 1
log.debug("send %s to %s:%i", method, *self.server)
try:
if method == 'server.version':
return await self.send_timed_server_version_request(
args, self.timeout)
request = asyncio.ensure_future(super().send_request(method, args))
while not request.done():
done, pending = await asyncio.wait([request],
timeout=self.timeout)
if pending:
log.debug("Time since last packet: %s",
perf_counter() - self.last_packet_received)
if (perf_counter() -
self.last_packet_received) < self.timeout:
continue
log.info("timeout sending %s to %s:%i", method,
*self.server)
raise asyncio.TimeoutError
if done:
return request.result()
except (RPCError, ProtocolError) as e:
log.warning(
"Wallet server (%s:%i) returned an error. Code: %s Message: %s",
*self.server, *e.args)
raise e
except ConnectionError:
log.warning("connection to %s:%i lost", *self.server)
self.synchronous_close()
raise
except asyncio.CancelledError:
log.info("cancelled sending %s to %s:%i", method, *self.server)
self.synchronous_close()
raise
finally:
self.pending_amount -= 1
async def ensure_session(self):
# Handles reconnecting and maintaining a session alive
# TODO: change to 'ping' on newer protocol (above 1.2)
retry_delay = default_delay = 1.0
while True:
try:
if self.is_closing():
await self.create_connection(self.timeout)
await self.ensure_server_version()
self._on_connect_cb()
if (perf_counter() - self.last_send
) > self.max_seconds_idle or self.response_time is None:
await self.ensure_server_version()
retry_delay = default_delay
except RPCError as e:
await self.close()
log.debug("Server error, ignoring for 1h: %s:%d -- %s",
*self.server, e.message)
retry_delay = 60 * 60
except IncompatibleWalletServerError:
await self.close()
retry_delay = 60 * 60
log.debug(
"Wallet server has an incompatible version, retrying in 1h: %s:%d",
*self.server)
except (asyncio.TimeoutError, OSError):
await self.close()
retry_delay = min(60, retry_delay * 2)
log.debug("Wallet server timeout (retry in %s seconds): %s:%d",
retry_delay, *self.server)
try:
await asyncio.wait_for(self.trigger_urgent_reconnect.wait(),
timeout=retry_delay)
except asyncio.TimeoutError:
pass
finally:
self.trigger_urgent_reconnect.clear()
async def ensure_server_version(self, required=None, timeout=3):
required = required or self.network.PROTOCOL_VERSION
response = await asyncio.wait_for(self.send_request(
'server.version', [__version__, required]),
timeout=timeout)
if tuple(int(piece) for piece in response[0].split(
".")) < self.network.MINIMUM_REQUIRED:
raise IncompatibleWalletServerError(*self.server)
return response
async def create_connection(self, timeout=6):
connector = Connector(lambda: self, *self.server)
start = perf_counter()
await asyncio.wait_for(connector.create_connection(), timeout=timeout)
self.connection_latency = perf_counter() - start
async def handle_request(self, request):
controller = self.network.subscription_controllers[request.method]
controller.add(request.args)
def connection_lost(self, exc):
log.debug("Connection lost: %s:%d", *self.server)
super().connection_lost(exc)
self.response_time = None
self.connection_latency = None
self._response_samples = 0
self.pending_amount = 0
self._on_disconnect_controller.add(True)
class Network:
PROTOCOL_VERSION = __version__
MINIMUM_REQUIRED = (0, 65, 0)
def __init__(self, ledger):
self.ledger = ledger
self.client: Optional[ClientSession] = None
self.server_features = None
# self._switch_task: Optional[asyncio.Task] = None
self.running = False
self.remote_height: int = 0
self._concurrency = asyncio.Semaphore(16)
self._on_connected_controller = StreamController()
self.on_connected = self._on_connected_controller.stream
self._on_header_controller = StreamController(
merge_repeated_events=True)
self.on_header = self._on_header_controller.stream
self._on_status_controller = StreamController(
merge_repeated_events=True)
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,
}
self.aiohttp_session: Optional[aiohttp.ClientSession] = None
self._urgent_need_reconnect = asyncio.Event()
self._loop_task: Optional[asyncio.Task] = None
self._keepalive_task: Optional[asyncio.Task] = None
@property
def config(self):
return self.ledger.config
def disconnect(self):
if self._keepalive_task and not self._keepalive_task.done():
self._keepalive_task.cancel()
self._keepalive_task = None
async def start(self):
if not self.running:
self.running = True
self.aiohttp_session = aiohttp.ClientSession()
self.on_header.listen(self._update_remote_height)
self._loop_task = asyncio.create_task(self.network_loop())
self._urgent_need_reconnect.set()
def loop_task_done_callback(f):
try:
f.result()
except Exception:
if self.running:
log.exception("wallet server connection loop crashed")
self._loop_task.add_done_callback(loop_task_done_callback)
async def resolve_spv_dns(self):
hostname_to_ip = {}
ip_to_hostnames = defaultdict(list)
async def resolve_spv(server, port):
try:
server_addr = await resolve_host(server, port, 'udp')
hostname_to_ip[server] = (server_addr, port)
ip_to_hostnames[(server_addr, port)].append(server)
except socket.error:
log.warning("error looking up dns for spv server %s:%i",
server, port)
except Exception:
log.exception("error looking up dns for spv server %s:%i",
server, port)
# accumulate the dns results
await asyncio.gather(*(resolve_spv(server, port)
for (server,
port) in self.config['default_servers']))
return hostname_to_ip, ip_to_hostnames
async def get_n_fastest_spvs(self,
timeout=3.0
) -> Dict[Tuple[str, int], SPVPong]:
loop = asyncio.get_event_loop()
pong_responses = asyncio.Queue()
connection = SPVStatusClientProtocol(pong_responses)
sent_ping_timestamps = {}
_, ip_to_hostnames = await self.resolve_spv_dns()
n = len(ip_to_hostnames)
log.info("%i possible spv servers to try (%i urls in config)", n,
len(self.config['default_servers']))
pongs = {}
try:
await loop.create_datagram_endpoint(lambda: connection,
('0.0.0.0', 0))
# could raise OSError if it cant bind
start = perf_counter()
for server in ip_to_hostnames:
connection.ping(server)
sent_ping_timestamps[server] = perf_counter()
while len(pongs) < n:
(remote, ts), pong = await asyncio.wait_for(
pong_responses.get(), timeout - (perf_counter() - start))
latency = ts - start
log.info(
"%s:%i has latency of %sms (available: %s, height: %i)",
'/'.join(ip_to_hostnames[remote]), remote[1],
round(latency * 1000, 2), pong.available, pong.height)
if pong.available:
pongs[remote] = pong
return pongs
except asyncio.TimeoutError:
if pongs:
log.info("%i/%i probed spv servers are accepting connections",
len(pongs), len(ip_to_hostnames))
return pongs
else:
log.warning(
"%i spv status probes failed, retrying later. servers tried: %s",
len(sent_ping_timestamps),
', '.join('/'.join(hosts) + f' ({ip})'
for ip, hosts in ip_to_hostnames.items()))
return {random.choice(list(ip_to_hostnames)): None}
finally:
connection.close()
async def connect_to_fastest(self) -> Optional[ClientSession]:
fastest_spvs = await self.get_n_fastest_spvs()
for (host, port) in fastest_spvs:
client = ClientSession(network=self, server=(host, port))
try:
await client.create_connection()
log.warning("Connected to spv server %s:%i", host, port)
await client.ensure_server_version()
return client
except (asyncio.TimeoutError, ConnectionError, OSError,
IncompatibleWalletServerError, RPCError):
log.warning("Connecting to %s:%d failed", host, port)
client._close()
return
async def network_loop(self):
sleep_delay = 30
while self.running:
await asyncio.wait(
[asyncio.sleep(30),
self._urgent_need_reconnect.wait()],
return_when=asyncio.FIRST_COMPLETED)
if self._urgent_need_reconnect.is_set():
sleep_delay = 30
self._urgent_need_reconnect.clear()
if not self.is_connected:
client = await self.connect_to_fastest()
if not client:
log.warning(
"failed to connect to any spv servers, retrying later")
sleep_delay *= 2
sleep_delay = min(sleep_delay, 300)
continue
log.debug("get spv server features %s:%i", *client.server)
features = await client.send_request('server.features', [])
self.client, self.server_features = client, features
log.info("subscribe to headers %s:%i", *client.server)
self._update_remote_height((await self.subscribe_headers(), ))
self._on_connected_controller.add(True)
server_str = "%s:%i" % client.server
log.info("maintaining connection to spv server %s", server_str)
self._keepalive_task = asyncio.create_task(
self.client.keepalive_loop())
try:
if not self._urgent_need_reconnect.is_set():
await asyncio.wait([
self._keepalive_task,
self._urgent_need_reconnect.wait()
],
return_when=asyncio.FIRST_COMPLETED)
else:
await self._keepalive_task
if self._urgent_need_reconnect.is_set():
log.warning("urgent reconnect needed")
self._urgent_need_reconnect.clear()
if self._keepalive_task and not self._keepalive_task.done(
):
self._keepalive_task.cancel()
except asyncio.CancelledError:
pass
finally:
self._keepalive_task = None
self.client = None
self.server_features = None
log.warning("connection lost to %s", server_str)
log.info("network loop finished")
async def stop(self):
self.running = False
self.disconnect()
if self._loop_task and not self._loop_task.done():
self._loop_task.cancel()
self._loop_task = None
if self.aiohttp_session:
await self.aiohttp_session.close()
self.aiohttp_session = None
@property
def is_connected(self):
return self.client and not self.client.is_closing()
def rpc(self,
list_or_method,
args,
restricted=True,
session: Optional[ClientSession] = None):
if session or self.is_connected:
session = session or self.client
return session.send_request(list_or_method, args)
else:
self._urgent_need_reconnect.set()
raise ConnectionError(
"Attempting to send rpc request when connection is not available."
)
async def retriable_call(self, function, *args, **kwargs):
async with self._concurrency:
while self.running:
if not self.is_connected:
log.warning(
"Wallet server unavailable, waiting for it to come back and retry."
)
self._urgent_need_reconnect.set()
await self.on_connected.first
try:
return await function(*args, **kwargs)
except asyncio.TimeoutError:
log.warning("Wallet server call timed out, retrying.")
except ConnectionError:
log.warning("connection error")
raise asyncio.CancelledError() # if we got here, we are shutting down
def _update_remote_height(self, header_args):
self.remote_height = header_args[0]["height"]
def get_transaction(self, tx_hash, known_height=None):
# use any server if its old, otherwise restrict to who gave us the history
restricted = known_height in (
None, -1, 0) or 0 > known_height > self.remote_height - 10
return self.rpc('blockchain.transaction.get', [tx_hash], restricted)
def get_transaction_batch(self, txids, restricted=True):
# use any server if its old, otherwise restrict to who gave us the history
return self.rpc('blockchain.transaction.get_batch', txids, restricted)
def get_transaction_and_merkle(self, tx_hash, known_height=None):
# use any server if its old, otherwise restrict to who gave us the history
restricted = known_height in (
None, -1, 0) or 0 > known_height > self.remote_height - 10
return self.rpc('blockchain.transaction.info', [tx_hash], restricted)
def get_transaction_height(self, tx_hash, known_height=None):
restricted = not known_height or 0 > known_height > self.remote_height - 10
return self.rpc('blockchain.transaction.get_height', [tx_hash],
restricted)
def get_merkle(self, tx_hash, height):
restricted = 0 > height > self.remote_height - 10
return self.rpc('blockchain.transaction.get_merkle', [tx_hash, height],
restricted)
def get_headers(self, height, count=10000, b64=False):
restricted = height >= self.remote_height - 100
return self.rpc('blockchain.block.headers', [height, count, 0, b64],
restricted)
# --- Subscribes, history and broadcasts are always aimed towards the master client directly
def get_history(self, address):
return self.rpc('blockchain.address.get_history', [address], True)
def broadcast(self, raw_transaction):
return self.rpc('blockchain.transaction.broadcast', [raw_transaction],
True)
def subscribe_headers(self):
return self.rpc('blockchain.headers.subscribe', [True], True)
async def subscribe_address(self, address, *addresses):
addresses = list((address, ) + addresses)
server_addr_and_port = self.client.server_address_and_port # on disconnect client will be None
try:
return await self.rpc('blockchain.address.subscribe', addresses,
True)
except asyncio.TimeoutError:
log.warning("timed out subscribing to addresses from %s:%i",
*server_addr_and_port)
# abort and cancel, we can't lose a subscription, it will happen again on reconnect
if self.client:
self.client.abort()
raise asyncio.CancelledError()
def unsubscribe_address(self, address):
return self.rpc('blockchain.address.unsubscribe', [address], True)
def get_server_features(self):
return self.rpc('server.features', (), restricted=True)
def resolve(self, urls, session_override=None):
return self.rpc('blockchain.claimtrie.resolve', urls, False,
session_override)
def claim_search(self, session_override=None, **kwargs):
return self.rpc('blockchain.claimtrie.search', kwargs, False,
session_override)
async def new_resolve(self, server, urls):
message = {
"method": "resolve",
"params": {
"urls": urls,
"protobuf": True
}
}
async with self.aiohttp_session.post(server, json=message) as r:
result = await r.json()
return result['result']
async def new_claim_search(self, server, **kwargs):
kwargs['protobuf'] = True
message = {"method": "claim_search", "params": kwargs}
async with self.aiohttp_session.post(server, json=message) as r:
result = await r.json()
return result['result']
async def sum_supports(self, server, **kwargs):
message = {"method": "support_sum", "params": kwargs}
async with self.aiohttp_session.post(server, json=message) as r:
result = await r.json()
return result['result']
class WalletServerPayer:
def __init__(self,
payment_period=24 * 60 * 60,
max_fee='1.0',
analytics_manager=None):
self.ledger = None
self.wallet = None
self.running = False
self.task = None
self.payment_period = payment_period
self.analytics_manager = analytics_manager
self.max_fee = max_fee
self._on_payment_controller = StreamController()
self.on_payment = self._on_payment_controller.stream
self.on_payment.listen(None,
on_error=lambda e: logging.warning(e.args[0]))
async def pay(self):
while self.running:
await asyncio.sleep(self.payment_period)
features = await self.ledger.network.retriable_call(
self.ledger.network.get_server_features)
address = features['payment_address']
amount = str(features['daily_fee'])
if not address or not amount:
continue
if not self.ledger.is_valid_address(address):
self._on_payment_controller.add_error(
ServerPaymentInvalidAddressError(address))
continue
if self.wallet.is_locked:
self._on_payment_controller.add_error(
ServerPaymentWalletLockedError())
continue
amount = lbc_to_dewies(
features['daily_fee']
) # check that this is in lbc and not dewies
limit = lbc_to_dewies(self.max_fee)
if amount > limit:
self._on_payment_controller.add_error(
ServerPaymentFeeAboveMaxAllowedError(
features['daily_fee'], self.max_fee))
continue
tx = await Transaction.create(
[], [
Output.pay_pubkey_hash(
amount, self.ledger.address_to_hash160(address))
], self.wallet.get_accounts_or_all(None),
self.wallet.get_account_or_default(None))
await self.ledger.broadcast(tx)
if self.analytics_manager:
await self.analytics_manager.send_credits_sent()
self._on_payment_controller.add(tx)
async def start(self, ledger=None, wallet=None):
if lbc_to_dewies(self.max_fee) < 1:
return
self.ledger = ledger
self.wallet = wallet
self.running = True
self.task = asyncio.ensure_future(self.pay())
self.task.add_done_callback(
lambda _: log.info("Stopping wallet server payments."))
async def stop(self):
if self.running:
self.running = False
self.task.cancel()