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agronholm
Switched start_blocking_portal() to use daemon threads
Changes
ThreadPoolExecutor used daemon threads in Python 3.8 and non-daemon threads in 3.9 onwards. But daemon threads are essential for the use case where we want to have a "loitering" blocking portal which will only be shut down via an atexit hook.
Related discussion: https://github.com/agronholm/anyio/discussions/743
Checklist
If this is a user-facing code change, like a bugfix or a new feature, please ensure that you've fulfilled the following conditions (where applicable):
- [X] You've added tests (in
tests/) added which would fail without your patch - [ ] You've updated the documentation (in
docs/, in case of behavior changes or new features) - [X] You've added a new changelog entry (in
docs/versionhistory.rst).
If this is a trivial change, like a typo fix or a code reformatting, then you can ignore these instructions.
Updating the changelog
If there are no entries after the last release, use **UNRELEASED** as the version.
If, say, your patch fixes issue #123, the entry should look like this:
* Fix big bad boo-boo in task groups (#123 <https://github.com/agronholm/anyio/issues/123>_; PR by @yourgithubaccount)
If there's no issue linked, just link to your pull request instead by updating the changelog after you've created the PR.
Possibly a random error which might be fixed by retrying the CI?
FAILED tests/streams/test_tls.py::TestTLSStream::test_extra_attributes[trio] - pytest.PytestUnhandledThreadExceptionWarning: Exception in thread Thread-4
<snip>
ConnectionResetError: [WinError 10054] An existing connection was forcibly closed by the remote host
Possibly a random error which might be fixed by retrying the CI?
FAILED tests/streams/test_tls.py::TestTLSStream::test_extra_attributes[trio] - pytest.PytestUnhandledThreadExceptionWarning: Exception in thread Thread-4 <snip> ConnectionResetError: [WinError 10054] An existing connection was forcibly closed by the remote host
Yup, randomly occurring Windows socket errors are among the hardest to figure out.
One possibility to avoid breaking subinterpreters here could be to make this opt-in: def start_blocking_portal(daemon: bool = False).
One possibility to avoid breaking subinterpreters here could be to make this opt-in:
def start_blocking_portal(daemon: bool = False).
I'm not too concerned about subinterpreters. I would've loved to add support for them, but they still don't have a stable Python API, and furthermore, once nogil becomes usable, they might become completely obsolete. I think we'll cross that bridge when we come to it, if ever.