commit 1dbff51fce762c212913c2c446d6e5945f283f75
parent 34413a9c306a297c833ed2b5e267e61ca297a225
Author: SomberNight <somber.night@protonmail.com>
Date: Fri, 5 Mar 2021 20:46:41 +0100
synchronizer: fix rare race where synchronizer could get stuck
Diffstat:
4 files changed, 22 insertions(+), 12 deletions(-)
diff --git a/electrum/lnverifier.py b/electrum/lnverifier.py
@@ -74,8 +74,9 @@ class LNChannelVerifier(NetworkJobOnDefaultServer):
self.unverified_channel_info[short_channel_id] = msg
return True
- async def _start_tasks(self):
- async with self.taskgroup as group:
+ async def _run_tasks(self, *, taskgroup):
+ await super()._run_tasks(taskgroup=taskgroup)
+ async with taskgroup as group:
await group.spawn(self.main)
async def main(self):
diff --git a/electrum/synchronizer.py b/electrum/synchronizer.py
@@ -74,9 +74,10 @@ class SynchronizerBase(NetworkJobOnDefaultServer):
self.add_queue = asyncio.Queue()
self.status_queue = asyncio.Queue()
- async def _start_tasks(self):
+ async def _run_tasks(self, *, taskgroup):
+ await super()._run_tasks(taskgroup=taskgroup)
try:
- async with self.taskgroup as group:
+ async with taskgroup as group:
await group.spawn(self.send_subscriptions())
await group.spawn(self.handle_status())
await group.spawn(self.main())
diff --git a/electrum/util.py b/electrum/util.py
@@ -46,6 +46,7 @@ from ipaddress import IPv4Address, IPv6Address
import random
import secrets
import functools
+from abc import abstractmethod, ABC
import attr
import aiohttp
@@ -1163,7 +1164,7 @@ class SilentTaskGroup(TaskGroup):
return super().spawn(*args, **kwargs)
-class NetworkJobOnDefaultServer(Logger):
+class NetworkJobOnDefaultServer(Logger, ABC):
"""An abstract base class for a job that runs on the main network
interface. Every time the main interface changes, the job is
restarted, and some of its internals are reset.
@@ -1179,8 +1180,10 @@ class NetworkJobOnDefaultServer(Logger):
self._network_request_semaphore = asyncio.Semaphore(100)
self._reset()
- asyncio.run_coroutine_threadsafe(self._restart(), network.asyncio_loop)
+ # every time the main interface changes, restart:
register_callback(self._restart, ['default_server_changed'])
+ # also schedule a one-off restart now, as there might already be a main interface:
+ asyncio.run_coroutine_threadsafe(self._restart(), network.asyncio_loop)
def _reset(self):
"""Initialise fields. Called every time the underlying
@@ -1190,13 +1193,17 @@ class NetworkJobOnDefaultServer(Logger):
async def _start(self, interface: 'Interface'):
self.interface = interface
- await interface.taskgroup.spawn(self._start_tasks)
+ await interface.taskgroup.spawn(self._run_tasks(taskgroup=self.taskgroup))
- async def _start_tasks(self):
- """Start tasks in self.taskgroup. Called every time the underlying
+ @abstractmethod
+ async def _run_tasks(self, *, taskgroup: TaskGroup) -> None:
+ """Start tasks in taskgroup. Called every time the underlying
server connection changes.
"""
- raise NotImplementedError() # implemented by subclasses
+ # If self.taskgroup changed, don't start tasks. This can happen if we have
+ # been restarted *just now*, i.e. after the _run_tasks coroutine object was created.
+ if taskgroup != self.taskgroup:
+ raise asyncio.CancelledError()
async def stop(self):
unregister_callback(self._restart)
diff --git a/electrum/verifier.py b/electrum/verifier.py
@@ -58,8 +58,9 @@ class SPV(NetworkJobOnDefaultServer):
self.merkle_roots = {} # txid -> merkle root (once it has been verified)
self.requested_merkle = set() # txid set of pending requests
- async def _start_tasks(self):
- async with self.taskgroup as group:
+ async def _run_tasks(self, *, taskgroup):
+ await super()._run_tasks(taskgroup=taskgroup)
+ async with taskgroup as group:
await group.spawn(self.main)
def diagnostic_name(self):
