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python - Python3.x RuntimeError：事件循环已关闭

问题描述

我在 aiohttp/asyncio 上做错了什么。如果我只是一次性运行以下代码，那么当我尝试run_my_job()在循环中从另一个文件中调用时，我的以下代码工作正常，如下所示：

main.py
========================================
 count = 0
    batch_count = math.ceil((abc.get_count()/100))
    print("there are {} batches to complete.".format(batch_count))
    while count < batch_count:
        print("starting batch {}...".format(count))
        abc.run_my_job()
        print("batch {} completed...".format(count))
        count += 1


abc.py
===============================
def run_my_job(self):
    self.queue_manager(self.do_stuff(all_the_tasks))

def queue_manager(self, method):
    print('starting event queue')
    loop = asyncio.get_event_loop()
    future = asyncio.ensure_future(method)
    loop.run_until_complete(future)
    loop.close()

async def async_post(self, resource, session, data):
    async with session.post(self.api_attr.api_endpoint + resource, headers=self.headers, data=data) as response:
        resp = await response.read()
    return resp

async def do_stuff(self, data):
    print('queueing tasks')

    tasks = []
    async with aiohttp.ClientSession() as session:
        for row in data:
            task = asyncio.ensure_future(self.async_post('my_api_endpoint', session, row))
            tasks.append(task)
        result = await asyncio.gather(*tasks)
        self.load_results(result)
# goes on to load_results() method that parses json and updates the DB.

我收到这些错误：

Traceback (most recent call last):
  File "C:/usr/PycharmProjects/api_framework/api_framework.py", line 37, in <module>
starting event queue
    abc.run_my_job()
  File "C:\usr\PycharmProjects\api_framework\api\abc\abc.py", line 77, in run_eligibility
    self.queue_manager(self.verify_eligibility(json_data))
  File "C:\usr\PycharmProjects\api_framework\api\abc\abc.py", line 187, in queue_manager
    future = asyncio.ensure_future(method)
  File "C:\Python36x64\lib\asyncio\tasks.py", line 512, in ensure_future
    task = loop.create_task(coro_or_future)
  File "C:\Python36x64\lib\asyncio\base_events.py", line 282, in create_task
    self._check_closed()
  File "C:\Python36x64\lib\asyncio\base_events.py", line 357, in _check_closed
    raise RuntimeError('Event loop is closed')
RuntimeError: Event loop is closed
sys:1: RuntimeWarning: coroutine 'Consumer.run_my_job' was never awaited

标签： pythonpython-3.6python-asyncioaiohttp

解决方案

看看这个函数：

def queue_manager(self, method):
    print('starting event queue')
    loop = asyncio.get_event_loop()
    future = asyncio.ensure_future(method)
    loop.run_until_complete(future)
    loop.close()

这就是您安排每个作业的方法。并且，在函数结束时，关闭事件循环。因此，在第一个作业运行后，您关闭事件循环。

如果您在那之后尝试运行更多作业，那么您显然是在尝试在封闭的事件循环上运行它们。（并且您的工作可以运行更多工作。）因此出现错误：

RuntimeError: Event loop is closed

只需删除loop.close()，问题就会消失。

我不确定这是否足以使您的程序正常工作，因为您没有给我们提供任何可运行示例附近的东西 - 另外，在您的真实代码中，run_my_job显然是一个协程，但它不在您发布的代码中这里。我在您发布的内容中没有看到任何其他明显的错误，但我不知道这意味着什么。

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