Scrapy FakeUserAgentError：获取浏览器时发生错误

Question

我使用 Scrapy FakeUserAgent 并在我的 Linux 服务器上不断收到此错误。

Traceback (most recent call last):
  File "/usr/local/lib64/python2.7/site-packages/twisted/internet/defer.py", line 1299, in _inlineCallbacks
    result = g.send(result)
  File "/usr/local/lib/python2.7/site-packages/scrapy/core/downloader/middleware.py", line 37, in process_request
    response = yield method(request=request, spider=spider)
  File "/usr/local/lib/python2.7/site-packages/scrapy_fake_useragent/middleware.py", line 27, in process_request
    request.headers.setdefault('User-Agent', self.ua.random)
  File "/usr/local/lib/python2.7/site-packages/fake_useragent/fake.py", line 98, in __getattr__
    raise FakeUserAgentError('Error occurred during getting browser')  # noqa
FakeUserAgentError: Error occurred during getting browser

当我同时运行多个蜘蛛时，我在 Linux 服务器上不断收到此错误。这个错误在我自己的笔记本电脑上很少发生。我应该怎么做才能避免这种情况？我需要提高内存还是其他什么？服务器的规格为 512MB RAM 和 1 个 vCPU。

Answer 1

我不确定 RAM 以及为什么错误只发生在具有最低规格的 Linux 服务器上。我通过使用fake-useragent后备功能解决了这个问题。遗憾的是，scrapy-fake-useragent没有提供任何功能来方便地设置它，所以我必须middlewares.py像这样覆盖中间件功能：

from fake_useragent import UserAgent
from scrapy_fake_useragent.middleware import RandomUserAgentMiddleware

class FakeUserAgentMiddleware(RandomUserAgentMiddleware):
    def __init__(self, crawler):
        super(FakeUserAgentMiddleware, self).__init__(crawler)
        # If failed to get random user agent, use the most common one
        self.ua = UserAgent(fallback='Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36')
        self.per_proxy = crawler.settings.get('RANDOM_UA_PER_PROXY', False)
        self.ua_type = crawler.settings.get('RANDOM_UA_TYPE', 'random')
        self.proxy2ua = {}

然后我像这样激活中间件settings.py：

DOWNLOADER_MIDDLEWARES = {
    'scrapy.downloadermiddlewares.useragent.UserAgentMiddleware': None,
    # 'scrapy_fake_useragent.middleware.RandomUserAgentMiddleware': 400, # disable the original middleware
    'myproject.middlewares.FakeUserAgentMiddleware': 400,
    # omitted
}

更新

尝试将 fake-useragent 更新到版本 0.1.5。我使用的是 0.1.4，升级后，问题从根本上消失了，而不是通过使用后备。