python-3.x - 运行时错误 : Event loop is closed

我正在尝试将 pyppeteer 和 quart 结合起来，但是由于启动浏览器需要很多时间，我宁愿全局处理它(使用异步锁)，这似乎意味着我需要手动处理清理。这是我的最小代码示例:

#!/usr/bin/env python3

import asyncio
import atexit
import pyppeteer

from quart import Quart, Response, request

app = Quart(__name__)
browser = asyncio.get_event_loop().run_until_complete(pyppeteer.launch())

async def cleanup_async():
    await browser.quit()

@atexit.register
def cleanup():
    asyncio.get_event_loop().run_until_complete(cleanup_async())

这是问题的样子:

[22:26:53] ➜  strokes git:(async_browser) ✗  % QUART_APP=/tmp/quart_cleanup.py timeout 10s quart run -h 0.0.0.0
Running on http://0.0.0.0:5000 (CTRL + C to quit)
Traceback (most recent call last):
  File "/home/d33tah/virtualenv-py3/bin/quart", line 11, in <module>
    sys.exit(main())
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/quart/cli.py", line 208, in main
    cli.main(args=args, prog_name=name)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/quart/cli.py", line 152, in main
    return super().main(*args, **kwargs)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/decorators.py", line 64, in new_func
    return ctx.invoke(f, obj, *args[1:], **kwargs)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/quart/cli.py", line 165, in run_command
    use_reloader=debug,
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/quart/serving/__init__.py", line 146, in run_app
    loop.run_until_complete(_observe_changes())
  File "/usr/lib/python3.6/asyncio/base_events.py", line 454, in run_until_complete
    self.run_forever()
  File "/usr/lib/python3.6/asyncio/base_events.py", line 421, in run_forever
    self._run_once()
  File "/usr/lib/python3.6/asyncio/base_events.py", line 1371, in _run_once
    event_list = self._selector.select(timeout)
  File "/usr/lib/python3.6/selectors.py", line 445, in select
    fd_event_list = self._epoll.poll(timeout, max_ev)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/pyppeteer/launcher.py", line 146, in _close_process
    asyncio.get_event_loop().run_until_complete(self.killChrome())
  File "/usr/lib/python3.6/asyncio/coroutines.py", line 84, in debug_wrapper
    return CoroWrapper(gen, None)
  File "/usr/lib/python3.6/asyncio/coroutines.py", line 92, in __init__
    self.gen = gen
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/pyppeteer/launcher.py", line 146, in _close_process
    asyncio.get_event_loop().run_until_complete(self.killChrome())
RuntimeError: coroutine wrapper <function debug_wrapper at 0x7f29878938c8> attempted to recursively wrap <code object killChrome at 0x7f2985e6edb0, file "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/pyppeteer/launcher.py", line 188>
Error in atexit._run_exitfuncs:
Traceback (most recent call last):
  File "/tmp/quart_cleanup.py", line 17, in cleanup
    asyncio.get_event_loop().run_until_complete(cleanup_async())
  File "/usr/lib/python3.6/asyncio/base_events.py", line 443, in run_until_complete
    self._check_closed()
  File "/usr/lib/python3.6/asyncio/base_events.py", line 357, in _check_closed
    raise RuntimeError('Event loop is closed')
RuntimeError: Event loop is closed
Error in atexit._run_exitfuncs:
Traceback (most recent call last):
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/pyppeteer/launcher.py", line 146, in _close_process
    asyncio.get_event_loop().run_until_complete(self.killChrome())
  File "/usr/lib/python3.6/asyncio/base_events.py", line 443, in run_until_complete
    self._check_closed()
  File "/usr/lib/python3.6/asyncio/base_events.py", line 357, in _check_closed
    raise RuntimeError('Event loop is closed')
RuntimeError: Event loop is closed
sys:1: RuntimeWarning: coroutine 'Launcher.killChrome' was never awaited
Exception ignored in: <object repr() failed>
Traceback (most recent call last):
  File "/usr/lib/python3.6/asyncio/coroutines.py", line 182, in __del__
    msg = '%r was never yielded from' % self
  File "/usr/lib/python3.6/asyncio/coroutines.py", line 99, in __repr__
    coro_repr = _format_coroutine(self)
  File "/usr/lib/python3.6/asyncio/coroutines.py", line 301, in _format_coroutine
    func = coro.func
AttributeError: 'CoroWrapper' object has no attribute 'func'
Task was destroyed but it is pending!
task: <Task pending coro=<Connection._recv_loop() running at /home/d33tah/virtualenv-py3/lib/python3.6/site-packages/pyppeteer/connection.py:54> wait_for=<Future pending cb=[<TaskWakeupMethWrapper object at 0x7f2985bd5828>()] created at /usr/lib/python3.6/asyncio/base_events.py:275>>
Exception ignored in: <coroutine object Connection._recv_loop at 0x7f2985b39780>
Traceback (most recent call last):
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/pyppeteer/connection.py", line 59, in _recv_loop
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/websockets/client.py", line 390, in __aexit__
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/websockets/protocol.py", line 370, in close
  File "/usr/lib/python3.6/asyncio/tasks.py", line 342, in wait_for
  File "/usr/lib/python3.6/asyncio/base_events.py", line 543, in call_later
  File "/usr/lib/python3.6/asyncio/base_events.py", line 553, in call_at
  File "/usr/lib/python3.6/asyncio/base_events.py", line 357, in _check_closed
RuntimeError: Event loop is closed
Task was destroyed but it is pending!
task: <Task pending coro=<WebSocketCommonProtocol.transfer_data() running at /home/d33tah/virtualenv-py3/lib/python3.6/site-packages/websockets/protocol.py:496> wait_for=<Future pending cb=[<TaskWakeupMethWrapper object at 0x7f2985b5f258>()] created at /usr/lib/python3.6/asyncio/base_events.py:275> cb=[<TaskWakeupMethWrapper object at 0x7f2985bd5e58>(), _wait.<locals>._on_completion() at /usr/lib/python3.6/asyncio/tasks.py:380]>
Task was destroyed but it is pending!
task: <Task pending coro=<WebSocketCommonProtocol.close_connection() running at /home/d33tah/virtualenv-py3/lib/python3.6/site-packages/websockets/protocol.py:711> wait_for=<Task pending coro=<WebSocketCommonProtocol.transfer_data() running at /home/d33tah/virtualenv-py3/lib/python3.6/site-packages/websockets/protocol.py:496> wait_for=<Future pending cb=[<TaskWakeupMethWrapper object at 0x7f2985b5f258>()] created at /usr/lib/python3.6/asyncio/base_events.py:275> cb=[<TaskWakeupMethWrapper object at 0x7f2985bd5e58>(), _wait.<locals>._on_completion() at /usr/lib/python3.6/asyncio/tasks.py:380]>>
Exception ignored in: <generator object WebSocketCommonProtocol.close_connection at 0x7f2985b39b48>
Traceback (most recent call last):
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/websockets/protocol.py", line 741, in close_connection
  File "/usr/lib/python3.6/asyncio/streams.py", line 306, in close
  File "/usr/lib/python3.6/asyncio/selector_events.py", line 622, in close
  File "/usr/lib/python3.6/asyncio/base_events.py", line 574, in call_soon
  File "/usr/lib/python3.6/asyncio/base_events.py", line 357, in _check_closed
RuntimeError: Event loop is closed
Task was destroyed but it is pending!
source_traceback: Object created at (most recent call last):
  File "/home/d33tah/virtualenv-py3/bin/quart", line 11, in <module>
    sys.exit(main())
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/quart/cli.py", line 208, in main
    cli.main(args=args, prog_name=name)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/quart/cli.py", line 152, in main
    return super().main(*args, **kwargs)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/decorators.py", line 64, in new_func
    return ctx.invoke(f, obj, *args[1:], **kwargs)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/quart/cli.py", line 165, in run_command
    use_reloader=debug,
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/quart/serving/__init__.py", line 146, in run_app
    loop.run_until_complete(_observe_changes())
  File "/usr/lib/python3.6/asyncio/base_events.py", line 454, in run_until_complete
    self.run_forever()
  File "/usr/lib/python3.6/asyncio/base_events.py", line 421, in run_forever
    self._run_once()
  File "/usr/lib/python3.6/asyncio/base_events.py", line 1418, in _run_once
    handle._run()
  File "/usr/lib/python3.6/asyncio/events.py", line 127, in _run
    self._callback(*self._args)
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/pyppeteer/connection.py", line 54, in _recv_loop
    resp = await self.connection.recv()
  File "/home/d33tah/virtualenv-py3/lib/python3.6/site-packages/websockets/protocol.py", line 305, in recv
    self.messages.get(), loop=self.loop)
task: <Task pending coro=<Queue.get() running at /usr/lib/python3.6/asyncio/queues.py:167> wait_for=<Future pending cb=[<TaskWakeupMethWrapper object at 0x7f2985b5f228>()] created at /usr/lib/python3.6/asyncio/base_events.py:275> cb=[_wait.<locals>._on_completion() at /usr/lib/python3.6/asyncio/tasks.py:380] created at /home/d33tah/virtualenv-py3/lib/python3.6/site-packages/websockets/protocol.py:305>
Exception ignored in: <generator object Queue.get at 0x7f2985810c50>
Traceback (most recent call last):
  File "/usr/lib/python3.6/asyncio/queues.py", line 169, in get
  File "/usr/lib/python3.6/asyncio/base_events.py", line 574, in call_soon
  File "/usr/lib/python3.6/asyncio/base_events.py", line 357, in _check_closed
RuntimeError: Event loop is closed

最佳答案

我使用 @app.before_serving 和 @app.after_serving 解决了这个问题。

关于python-3.x - 运行时错误 : Event loop is closed，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/50556251/