Currently, asyncio.wait_for(fut), upon reaching the timeout deadline,
cancels the future and returns immediately. This is problematic for
when *fut* is a Task, because it will be left running for an arbitrary
amount of time. This behavior is iself surprising and may lead to
related bugs such as the one described in bpo-33638:
condition = asyncio.Condition()
async with condition:
await asyncio.wait_for(condition.wait(), timeout=0.5)
Currently, instead of raising a TimeoutError, the above code will fail
with `RuntimeError: cannot wait on un-acquired lock`, because
`__aexit__` is reached _before_ `condition.wait()` finishes its
cancellation and re-acquires the condition lock.
To resolve this, make `wait_for` await for the task cancellation.
The tradeoff here is that the `timeout` promise may be broken if the
task decides to handle its cancellation in a slow way. This represents
a behavior change and should probably not be back-patched to 3.6 and
earlier.
Use transport.set_write_buffer_limits() in sendfile tests of
test_asyncio to make sure that the protocol is paused after sending
4 KiB. Previously,
test_sendfile_fallback_close_peer_in_the_middle_of_receiving() failed
on FreeBSD if the DATA was smaller than the default limit of 64 KiB.
Fix a race condition in SSLProtocol.connection_made() of
asyncio.sslproto: start immediately the handshake instead of using
call_soon(). Previously, data_received() could be called before the
handshake started, causing the handshake to hang or fail.
In this commit:
* Support BufferedProtocol in set_protocol() and start_tls()
* Fix proactor to cancel readers reliably
* Update tests to be compatible with OpenSSL 1.1.1
* Clarify BufferedProtocol docs
* Bump TLS tests timeouts to 60 seconds; eliminate possible race from start_serving
* Rewrite test_start_tls_server_1
* bpo-33263 Fix FD leak in _SelectorSocketTransport. (GH-6450)
Under particular circumstances _SelectorSocketTransport can try to add a reader
even the transport is already being closed. This can lead to FD leak and
invalid stated of the following connections. Fixed the SelectorSocketTransport
to add the reader only if the trasport is still active.
Fix typo from commit 6370f345e1
Signed-off-by: Christian Heimes <christian@python.org>
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# Pull Request title
It should be in the following format:
```
bpo-NNNN: Summary of the changes made
```
Where: bpo-NNNN refers to the issue number in the https://bugs.python.org.
Most PRs will require an issue number. Trivial changes, like fixing a typo, do not need an issue.
# Backport Pull Request title
If this is a backport PR (PR made against branches other than `master`),
please ensure that the PR title is in the following format:
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[X.Y] <title from the original PR> (GH-NNNN)
```
Where: [X.Y] is the branch name, e.g. [3.6].
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-->
<!-- issue-number: bpo-32262 -->
https://bugs.python.org/issue32262
<!-- /issue-number -->
Fix the following bugs in the C implementation:
* get_future_loop() silenced all exceptions raised when look up the get_loop
attribute, not just an AttributeError.
* enter_task() silenced all exceptions raised when look up the current task,
not just a KeyError.
* repr() was called for a borrowed link in enter_task() and task_step_impl().
* str() was used instead of repr() in formatting one error message (in
Python implementation too).
* There where few reference leaks in error cases.
The proactor event loop has a race condition when reading with
pausing/resuming. `resume_reading()` unconditionally schedules the read
function to read from the current future. If `resume_reading()` was
called before the previously scheduled done callback fires, this results
in two attempts to get the data from the most recent read and an
assertion failure. This commit tracks whether or not `resume_reading`
needs to reschedule the callback to restart the loop, preventing a
second attempt to read the data.
bpo-31399: Let OpenSSL verify hostname and IP
The ssl module now uses OpenSSL's X509_VERIFY_PARAM_set1_host() and
X509_VERIFY_PARAM_set1_ip() API to verify hostname and IP addresses.
* Remove match_hostname calls
* Check for libssl with set1_host, libssl must provide X509_VERIFY_PARAM_set1_host()
* Add documentation for OpenSSL 1.0.2 requirement
* Don't support OpenSSL special mode with a leading dot, e.g. ".example.org" matches "www.example.org". It's not standard conform.
* Add hostname_checks_common_name
Signed-off-by: Christian Heimes <christian@python.org>
* bpo-32662: Implement Server.start_serving() and Server.serve_forever()
New methods:
* Server.start_serving(),
* Server.serve_forever(), and
* Server.is_serving().
Add 'start_serving' keyword parameter to loop.create_server() and
loop.create_unix_server().
Specifically, it's not possible to subclass Task/Future classes
and override the following methods:
* Future._schedule_callbacks
* Task._step
* Task._wakeup
* Add coro.cr_origin and sys.set_coroutine_origin_tracking_depth
* Use coroutine origin information in the unawaited coroutine warning
* Stop using set_coroutine_wrapper in asyncio debug mode
* In BaseEventLoop.set_debug, enable debugging in the correct thread