Scrapy Shell Always Raises RuntimeError but Works Fine

[CodingMoeButa]

Description

Scrapy Shell always raises RuntimeError even though I request any URL, but results fine.

Steps to Reproduce

Execute scrapy shell 'https://any.url', return:

2022-12-01 21:30:51 [scrapy.utils.log] INFO: Versions: lxml 4.9.1.0, libxml2 2.9.12, cssselect 1.1.0, parsel 1.7.0, w3lib 2.0.1, Twisted 22.10.0, Python 3.10.5 (tags/v3.10.5:f377153, Jun  6 2022, 16:14:13) [MSC v.1929 64 bit (AMD64)], pyOpenSSL 22.1.0 (OpenSSL 3.0.7 1 Nov 2022), cryptography 38.0.3, Platform Windows-10-10.0.19045-SP0
2022-12-01 21:30:51 [scrapy.crawler] INFO: Overridden settings:
{'AUTOTHROTTLE_ENABLED': True,
 'AUTOTHROTTLE_START_DELAY': 1,
 'AUTOTHROTTLE_TARGET_CONCURRENCY': 8.0,
 'BOT_NAME': 'lightnovel',
 'CONCURRENT_REQUESTS': 32,
 'CONCURRENT_REQUESTS_PER_IP': 16,
 'DUPEFILTER_CLASS': 'scrapy.dupefilters.BaseDupeFilter',
 'LOGSTATS_INTERVAL': 0,
 'LOG_LEVEL': 'INFO',
 'NEWSPIDER_MODULE': 'lightnovel.spiders',
 'REQUEST_FINGERPRINTER_IMPLEMENTATION': '2.7',
 'SPIDER_MODULES': ['lightnovel.spiders'],
 'TWISTED_REACTOR': 'twisted.internet.asyncioreactor.AsyncioSelectorReactor',
 'USER_AGENT': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 '
               '(KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.36 '
               'Edg/107.0.1418.52 Scrapy/2.7.1 (+https://scrapy.org) '
               'LightnovelSpider/3.0'}
2022-12-01 21:30:51 [scrapy.extensions.telnet] INFO: Telnet Password: 797751ad72cc1c35
2022-12-01 21:30:51 [scrapy.middleware] INFO: Enabled extensions:
['scrapy.extensions.corestats.CoreStats',
 'scrapy.extensions.telnet.TelnetConsole',
 'scrapy.extensions.throttle.AutoThrottle']
2022-12-01 21:30:51 [scrapy.middleware] INFO: Enabled downloader middlewares:
['scrapy.downloadermiddlewares.httpauth.HttpAuthMiddleware',
 'scrapy.downloadermiddlewares.downloadtimeout.DownloadTimeoutMiddleware',
 'scrapy.downloadermiddlewares.defaultheaders.DefaultHeadersMiddleware',
 'scrapy.downloadermiddlewares.useragent.UserAgentMiddleware',
 'lightnovel.middlewares.LightnovelDownloaderMiddleware',
 'scrapy.downloadermiddlewares.retry.RetryMiddleware',
 'scrapy.downloadermiddlewares.redirect.MetaRefreshMiddleware',
 'scrapy.downloadermiddlewares.httpcompression.HttpCompressionMiddleware',
 'scrapy.downloadermiddlewares.redirect.RedirectMiddleware',
 'scrapy.downloadermiddlewares.cookies.CookiesMiddleware',
 'scrapy.downloadermiddlewares.httpproxy.HttpProxyMiddleware',
 'scrapy.downloadermiddlewares.stats.DownloaderStats']
2022-12-01 21:30:51 [scrapy.middleware] INFO: Enabled spider middlewares:
['scrapy.spidermiddlewares.httperror.HttpErrorMiddleware',
 'scrapy.spidermiddlewares.offsite.OffsiteMiddleware',
 'scrapy.spidermiddlewares.referer.RefererMiddleware',
 'scrapy.spidermiddlewares.urllength.UrlLengthMiddleware',
 'scrapy.spidermiddlewares.depth.DepthMiddleware']
2022-12-01 21:30:51 [scrapy.middleware] INFO: Enabled item pipelines:
[]
2022-12-01 21:30:51 [scrapy.extensions.telnet] INFO: Telnet console listening on 127.0.0.1:6023
2022-12-01 21:30:51 [scrapy.core.engine] INFO: Spider opened
2022-12-01 21:30:52 [default] INFO: Spider opened: default
2022-12-01 21:30:52 [scrapy.core.scraper] ERROR: Spider error processing <GET https://www.baidu.com> (referer: None)
Traceback (most recent call last):
  File "C:\Python310\lib\site-packages\twisted\internet\defer.py", line 892, in _runCallbacks
    current.result = callback(  # type: ignore[misc]
  File "C:\Python310\lib\site-packages\scrapy\utils\defer.py", line 285, in f
    return deferred_from_coro(coro_f(*coro_args, **coro_kwargs))
  File "C:\Python310\lib\site-packages\scrapy\utils\defer.py", line 272, in deferred_from_coro
    event_loop = get_asyncio_event_loop_policy().get_event_loop()
  File "C:\Python310\lib\asyncio\events.py", line 656, in get_event_loop
    raise RuntimeError('There is no current event loop in thread %r.'
RuntimeError: There is no current event loop in thread 'Thread-1 (start)'.
2022-12-01 21:30:52 [py.warnings] WARNING: C:\Python310\lib\site-packages\twisted\internet\defer.py:892: RuntimeWarning: coroutine 'SpiderMiddlewareManager.scrape_response.<locals>.process_callback_output' was never awaited
  current.result = callback(  # type: ignore[misc]

[s] Available Scrapy objects:
[s]   scrapy     scrapy module (contains scrapy.Request, scrapy.Selector, etc)
[s]   crawler    <scrapy.crawler.Crawler object at 0x000002EFC594F6D0>
[s]   item       {}
[s]   request    <GET https://www.baidu.com>
[s]   response   <200 https://www.baidu.com>
[s]   settings   <scrapy.settings.Settings object at 0x000002EFC594F670>
[s]   spider     <DefaultSpider 'default' at 0x2efc5e09450>
[s] Useful shortcuts:
[s]   fetch(url[, redirect=True]) Fetch URL and update local objects (by default, redirects are followed)
[s]   fetch(req)                  Fetch a scrapy.Request and update local objects
[s]   shelp()           Shell help (print this help)
[s]   view(response)    View response in a browser
>>>

Expected behavior: It is not expected to show:

2022-12-01 21:30:52 [scrapy.core.scraper] ERROR: Spider error processing <GET https://www.baidu.com> (referer: None)
Traceback (most recent call last):
  File "C:\Python310\lib\site-packages\twisted\internet\defer.py", line 892, in _runCallbacks
    current.result = callback(  # type: ignore[misc]
  File "C:\Python310\lib\site-packages\scrapy\utils\defer.py", line 285, in f
    return deferred_from_coro(coro_f(*coro_args, **coro_kwargs))
  File "C:\Python310\lib\site-packages\scrapy\utils\defer.py", line 272, in deferred_from_coro
    event_loop = get_asyncio_event_loop_policy().get_event_loop()
  File "C:\Python310\lib\asyncio\events.py", line 656, in get_event_loop
    raise RuntimeError('There is no current event loop in thread %r.'
RuntimeError: There is no current event loop in thread 'Thread-1 (start)'.
2022-12-01 21:30:52 [py.warnings] WARNING: C:\Python310\lib\site-packages\twisted\internet\defer.py:892: RuntimeWarning: coroutine 'SpiderMiddlewareManager.scrape_response.<locals>.process_callback_output' was never awaited
  current.result = callback(  # type: ignore[misc]

Reproduces how often: Always.

Versions

Scrapy : 2.7.1
lxml : 4.9.1.0
libxml2 : 2.9.12
cssselect : 1.1.0
parsel : 1.7.0
w3lib : 2.0.1
Twisted : 22.10.0
Python : 3.10.5 (tags/v3.10.5:f377153, Jun 6 2022, 16:14:13) [MSC v.1929 64 bit (AMD64)]
pyOpenSSL : 22.1.0 (OpenSSL 3.0.7 1 Nov 2022)
cryptography : 38.0.3
Platform : Windows-10-10.0.19045-SP0

[wRAR]

This is certainly the same problem as in #5740. However, what do you mean by working fine? Are you able to access the response?

Also, is the result different when you use fetch(url) instead of passing it as a command line argument?

[CodingMoeButa]

Yes, I meant I am able to access the response.
The results have no difference between using fetch(url) and passing it as a command line argument.

[wRAR]

Interesting, thanks!

Are you able to run spiders with scrapy crawl in this project?

[CodingMoeButa]

Everything works fine both scrapy crawl and scrapy runspider without exceptions.

[wRAR]

Great, then it looks like it's specific to scrapy shell. I'm going to close this issue and write the info from you in the previous one. Thanks for your assistance!