pallectrum

Files

f321x 08673d3534 util: cleanup asyncio event loop after stopping

I noticed many ResourceWarning when running regtests with
PYTHONASYNCIODEBUG=1 and PYTHONDEVMODE=1, each time a daemon
gets stopped the asyncio loop wouldn't get properly cleaned up:

```
(env) user@hp:~/code/electrum-fork$ python3 -m unittest tests.regtest.TestLightningAB.test_lnwatcher_waits_until_fees_go_down
***** test_lnwatcher_waits_until_fees_go_down ******
initializing alice
  0.67 | W | asyncio | Executing <Task finished name='Task-1' coro=<run_offline_command() done, defined at /home/user/code/electrum-fork/./run_electrum:229> result={'msg': 'Please keep ... your wallet.', 'path': '/tmp/alice/r...efault_wallet', 'seed': 'fiction sadd...it radar desk'} created at /home/user/code/electrum-fork/electrum/util.py:1760> took 0.280 seconds
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
funding alice
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
f84277454a04243e500cf84c67aad16e04dd7a88ffa849ffcf20ce3f9af277df
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
initializing bob
  0.54 | W | asyncio | Executing <Task finished name='Task-1' coro=<run_offline_command() done, defined at /home/user/code/electrum-fork/./run_electrum:229> result={'msg': 'Please keep ... your wallet.', 'path': '/tmp/bob/reg...efault_wallet', 'seed': 'wink loud so...ory myth case'} created at /home/user/code/electrum-fork/electrum/util.py:1760> took 0.195 seconds
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
funding bob
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
f68b651e84dc8547f54dd09129018a2d0d256dedc8ccc48595ae172de895371a
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
mining 1 blocks
starting daemon (PID 38153)
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
/tmp/alice/regtest/wallets/default_wallet
/usr/lib64/python3.14/asyncio/base_events.py:758: ResourceWarning: unclosed event loop <_UnixSelectorEventLoop running=False closed=False debug=True>
```

This commits adds some cleanup to `util.create_and_start_event_loop()`
to
1. cancel remaining tasks
2. shut down asyncgens
3. shutdown the default executor
4. call loop.close() to free the resources allocated to the loop
See https://stackoverflow.com/questions/30765606/whats-the-correct-way-to-clean-up-after-an-interrupted-event-loop

This seems to reliably solve the mentioned `ResourceWarning`.

2025-10-28 14:53:35 +01:00