vcrpy
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kevin1024
Fixed Async `httpx` Request Handling in `vcr.py` Sync Contexts
Should now correctly handle asynchronous httpx requests when called from synchronous functions. Previously, using asyncio.run() in _sync_vcr_send caused issues in environments with an existing event loop, like aiohttp servers.
Solution:
- Implemented a
run_async_from_syncfunction usingThreadPoolExecutorto execute async tasks from synchronous functions. - Replaced
asyncio.run()in_sync_vcr_sendwithrun_async_from_sync.
This change ensures httpx requests are processed correctly in vcr.py's synchronous operations.
I think this is related to #817
Here's a reproducer:
import asyncio
import httpx
import pytest
from aiohttp import web
import vcr
my_vcr = vcr.VCR(cassette_library_dir='cassettes', record_mode='once')
@my_vcr.use_cassette('test.yml')
async def handle_request(request):
client = httpx.Client()
try:
response = client.get('http://httpbin.org/get')
finally:
client.close()
return web.Response(text=response.text, status=response.status_code)
def create_app():
app = web.Application()
app.router.add_get('/', handle_request)
return app
@pytest.mark.asyncio
async def test_server(aiohttp_client):
app = create_app()
client = await aiohttp_client(app)
resp = await client.get('/')
assert resp.status == 200
(there's some issue on my branch with an unclosed event loop but I couldn't figure it out, I think it's related to the asyncio fixture but I'm not sure)
Before:
============================= test session starts ==============================
platform linux -- Python 3.12.2, pytest-8.1.1, pluggy-1.4.0
rootdir: /home/fabian/projects/github.com/kevin1024/vcrpy
configfile: pyproject.toml
plugins: anyio-3.7.1, recording-0.13.1, asyncio-0.23.6, aiohttp-1.0.5
asyncio: mode=Mode.STRICT
collected 1 item
repro.py FE [100%]
==================================== ERRORS ====================================
_______________________ ERROR at teardown of test_server _______________________
cls = <class '_pytest.runner.CallInfo'>
func = <function call_and_report.<locals>.<lambda> at 0x7fcb6d557c40>
when = 'teardown'
reraise = (<class '_pytest.outcomes.Exit'>, <class 'KeyboardInterrupt'>)
@classmethod
def from_call(
cls,
func: Callable[[], TResult],
when: Literal["collect", "setup", "call", "teardown"],
reraise: Optional[
Union[Type[BaseException], Tuple[Type[BaseException], ...]]
] = None,
) -> "CallInfo[TResult]":
"""Call func, wrapping the result in a CallInfo.
:param func:
The function to call. Called without arguments.
:param when:
The phase in which the function is called.
:param reraise:
Exception or exceptions that shall propagate if raised by the
function, instead of being wrapped in the CallInfo.
"""
excinfo = None
start = timing.time()
precise_start = timing.perf_counter()
try:
> result: Optional[TResult] = func()
../../../../.local/lib/python3.12/site-packages/_pytest/runner.py:340:
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
../../../../.local/lib/python3.12/site-packages/_pytest/runner.py:240: in <lambda>
lambda: runtest_hook(item=item, **kwds), when=when, reraise=reraise
../../../../.local/lib/python3.12/site-packages/pluggy/_hooks.py:501: in __call__
return self._hookexec(self.name, self._hookimpls.copy(), kwargs, firstresult)
../../../../.local/lib/python3.12/site-packages/pluggy/_manager.py:119: in _hookexec
return self._inner_hookexec(hook_name, methods, kwargs, firstresult)
../../../../.local/lib/python3.12/site-packages/_pytest/threadexception.py:92: in pytest_runtest_teardown
yield from thread_exception_runtest_hook()
../../../../.local/lib/python3.12/site-packages/_pytest/threadexception.py:63: in thread_exception_runtest_hook
yield
../../../../.local/lib/python3.12/site-packages/_pytest/unraisableexception.py:95: in pytest_runtest_teardown
yield from unraisable_exception_runtest_hook()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
def unraisable_exception_runtest_hook() -> Generator[None, None, None]:
with catch_unraisable_exception() as cm:
try:
yield
finally:
if cm.unraisable:
if cm.unraisable.err_msg is not None:
err_msg = cm.unraisable.err_msg
else:
err_msg = "Exception ignored in"
msg = f"{err_msg}: {cm.unraisable.object!r}\n\n"
msg += "".join(
traceback.format_exception(
cm.unraisable.exc_type,
cm.unraisable.exc_value,
cm.unraisable.exc_traceback,
)
)
> warnings.warn(pytest.PytestUnraisableExceptionWarning(msg))
E pytest.PytestUnraisableExceptionWarning: Exception ignored in: <coroutine object _record_responses at 0x7fcb6d57bbc0>
E
E Traceback (most recent call last):
E File "/usr/lib64/python3.12/warnings.py", line 553, in _warn_unawaited_coroutine
E warn(msg, category=RuntimeWarning, stacklevel=2, source=coro)
E RuntimeWarning: coroutine '_record_responses' was never awaited
../../../../.local/lib/python3.12/site-packages/_pytest/unraisableexception.py:80: PytestUnraisableExceptionWarning
------------------------------ Captured log call -------------------------------
ERROR aiohttp.server:web_protocol.py:421 Error handling request
Traceback (most recent call last):
File "/home/fabian/.local/lib/python3.12/site-packages/aiohttp/web_protocol.py", line 452, in _handle_request
resp = await request_handler(request)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/aiohttp/web_app.py", line 543, in _handle
resp = await handler(request)
^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/projects/github.com/kevin1024/vcrpy/vcr/_handle_coroutine.py", line 3, in handle_coroutine
return await fn(cassette)
^^^^^^^^^^^^^^^^^^
File "/home/fabian/projects/github.com/kevin1024/vcrpy/repro.py", line 15, in handle_request
response = client.get('http://httpbin.org/get')
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/httpx/_client.py", line 1055, in get
return self.request(
^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/httpx/_client.py", line 828, in request
return self.send(request, auth=auth, follow_redirects=follow_redirects)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/httpx/_client.py", line 915, in send
response = self._send_handling_auth(
^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/httpx/_client.py", line 943, in _send_handling_auth
response = self._send_handling_redirects(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/httpx/_client.py", line 980, in _send_handling_redirects
response = self._send_single_request(request)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/projects/github.com/kevin1024/vcrpy/vcr/stubs/httpx_stubs.py", line 184, in _inner_send
return _sync_vcr_send(cassette, real_send, *args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/projects/github.com/kevin1024/vcrpy/vcr/stubs/httpx_stubs.py", line 177, in _sync_vcr_send
asyncio.run(_record_responses(cassette, vcr_request, real_response, aread=False))
File "/usr/lib64/python3.12/asyncio/runners.py", line 190, in run
raise RuntimeError(
RuntimeError: asyncio.run() cannot be called from a running event loop
=================================== FAILURES ===================================
_________________________________ test_server __________________________________
aiohttp_client = <function aiohttp_client.<locals>.go at 0x7fcb6d556f20>
@pytest.mark.asyncio
async def test_server(aiohttp_client):
app = create_app()
client = await aiohttp_client(app)
resp = await client.get('/')
> assert resp.status == 200
E AssertionError: assert 500 == 200
E + where 500 = <ClientResponse(http://127.0.0.1:33117/) [500 Internal Server Error]>\n<CIMultiDictProxy('Content-Type': 'text/plain; c...Length': '55', 'Date': 'Wed, 03 Apr 2024 19:02:16 GMT', 'Server': 'Python/3.12 aiohttp/3.9.3', 'Connection': 'close')>\n.status
repro.py:32: AssertionError
------------------------------ Captured log call -------------------------------
ERROR aiohttp.server:web_protocol.py:421 Error handling request
Traceback (most recent call last):
File "/home/fabian/.local/lib/python3.12/site-packages/aiohttp/web_protocol.py", line 452, in _handle_request
resp = await request_handler(request)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/aiohttp/web_app.py", line 543, in _handle
resp = await handler(request)
^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/projects/github.com/kevin1024/vcrpy/vcr/_handle_coroutine.py", line 3, in handle_coroutine
return await fn(cassette)
^^^^^^^^^^^^^^^^^^
File "/home/fabian/projects/github.com/kevin1024/vcrpy/repro.py", line 15, in handle_request
response = client.get('http://httpbin.org/get')
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/httpx/_client.py", line 1055, in get
return self.request(
^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/httpx/_client.py", line 828, in request
return self.send(request, auth=auth, follow_redirects=follow_redirects)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/httpx/_client.py", line 915, in send
response = self._send_handling_auth(
^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/httpx/_client.py", line 943, in _send_handling_auth
response = self._send_handling_redirects(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/.local/lib/python3.12/site-packages/httpx/_client.py", line 980, in _send_handling_redirects
response = self._send_single_request(request)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/projects/github.com/kevin1024/vcrpy/vcr/stubs/httpx_stubs.py", line 184, in _inner_send
return _sync_vcr_send(cassette, real_send, *args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/fabian/projects/github.com/kevin1024/vcrpy/vcr/stubs/httpx_stubs.py", line 177, in _sync_vcr_send
asyncio.run(_record_responses(cassette, vcr_request, real_response, aread=False))
File "/usr/lib64/python3.12/asyncio/runners.py", line 190, in run
raise RuntimeError(
RuntimeError: asyncio.run() cannot be called from a running event loop
=========================== short test summary info ============================
FAILED repro.py::test_server - AssertionError: assert 500 == 200
ERROR repro.py::test_server - pytest.PytestUnraisableExceptionWarning: Except...
========================== 1 failed, 1 error in 0.80s ==========================
After:
============================= test session starts ==============================
platform linux -- Python 3.12.2, pytest-8.1.1, pluggy-1.4.0
rootdir: /home/fabian/projects/github.com/kevin1024/vcrpy
configfile: pyproject.toml
plugins: anyio-3.7.1, recording-0.13.1, asyncio-0.23.6, aiohttp-1.0.5
asyncio: mode=Mode.STRICT
collected 1 item
repro.py .E [100%]
==================================== ERRORS ====================================
_______________________ ERROR at teardown of test_server _______________________
def _close_event_loop() -> None:
policy = asyncio.get_event_loop_policy()
try:
loop = policy.get_event_loop()
except RuntimeError:
loop = None
if loop is not None:
if not loop.is_closed():
> warnings.warn(
_UNCLOSED_EVENT_LOOP_WARNING % loop,
DeprecationWarning,
)
E DeprecationWarning: pytest-asyncio detected an unclosed event loop when tearing down the event_loop
E fixture: <_UnixSelectorEventLoop running=False closed=False debug=False>
E pytest-asyncio will close the event loop for you, but future versions of the
E library will no longer do so. In order to ensure compatibility with future
E versions, please make sure that:
E 1. Any custom "event_loop" fixture properly closes the loop after yielding it
E 2. The scopes of your custom "event_loop" fixtures do not overlap
E 3. Your code does not modify the event loop in async fixtures or tests
../../../../.local/lib/python3.12/site-packages/pytest_asyncio/plugin.py:818: DeprecationWarning
=========================== short test summary info ============================
ERROR repro.py::test_server - DeprecationWarning: pytest-asyncio detected an ...
========================== 1 passed, 1 error in 0.65s ==========================
looks like this may be a dupe fix of #825
Yes, maybe; I've tested both and yours just works (while the other don't).
Thanks, pal. 🙏🏻
Per #825, we upgraded a number of dependencies around langchain and began having an issue in one of our vcr recordings that uses the openai client synchronously (in a synchronous kafka consumer). I didn't dig into why exactly we only seem to have an issue around this specific synchronous playback.
However, I noticed this dupe and after testing can confirm it is working for us (after rebasing on master). I've closed #825 in favor of this.
Can we please get this rebased and merged for release?
