蜘蛛关闭时如何退出硒驱动程序答案

【问题标题】：How to quit selenium driver when spider is closed蜘蛛关闭时如何退出硒驱动程序
【发布时间】：2015-08-12 12:10:47
【问题描述】：

我有一个蜘蛛，我必须使用 Selenium 来抓取页面上的动态数据。这是它的样子：

class MySpider(
    name = 'myspider'
    start_urls = ['http://example.org']

    def __init__(self, *args, **kwargs):
        super(, self).__init__(*args, **kwargs)
        self.driver = webdriver.Firefox()
        self.driver.implicitly_wait(5)
        dispatcher.connect(self.spider_closed, signals.spider_closed)

    def spider_closed(self, spider):
        if self.driver:
            self.driver.quit()
            self.driver = None

这里的问题是，当我在 Scrapyd 中取消作业时，它不会停止，直到我手动关闭窗口。当我将蜘蛛部署到真实服务器时，我显然无法做到这一点。

这是我每次点击“取消”时在 Scrapyd 日志中看到的内容：

2015-08-12 13:48:13+0300 [HTTPChannel,208,127.0.0.1] Unhandled Error
    Traceback (most recent call last):
      File "/home/dmitry/.virtualenvs/myproject/local/lib/python2.7/site-packages/twisted/web/http.py", line 1731, in allContentReceived
        req.requestReceived(command, path, version)
      File "/home/dmitry/.virtualenvs/myproject/local/lib/python2.7/site-packages/twisted/web/http.py", line 827, in requestReceived
        self.process()
      File "/home/dmitry/.virtualenvs/myproject/local/lib/python2.7/site-packages/twisted/web/server.py", line 189, in process
        self.render(resrc)
      File "/home/dmitry/.virtualenvs/myproject/local/lib/python2.7/site-packages/twisted/web/server.py", line 238, in render
        body = resrc.render(self)
    --- <exception caught here> ---
      File "/home/dmitry/.virtualenvs/myproject/local/lib/python2.7/site-packages/scrapyd/webservice.py", line 18, in render
        return JsonResource.render(self, txrequest)
      File "/home/dmitry/.virtualenvs/myproject/local/lib/python2.7/site-packages/scrapy/utils/txweb.py", line 10, in render
        r = resource.Resource.render(self, txrequest)
      File "/home/dmitry/.virtualenvs/myproject/local/lib/python2.7/site-packages/twisted/web/resource.py", line 250, in render
        return m(request)
      File "/home/dmitry/.virtualenvs/myproject/local/lib/python2.7/site-packages/scrapyd/webservice.py", line 55, in render_POST
        s.transport.signalProcess(signal)
      File "/home/dmitry/.virtualenvs/myproject/local/lib/python2.7/site-packages/twisted/internet/process.py", line 339, in signalProcess
        raise ProcessExitedAlready()
    twisted.internet.error.ProcessExitedAlready:

但该作业仍在作业列表中，并标记为“正在运行”。那么如何关闭驱动呢？

【问题讨论】：

您最好在这里使用蜘蛛中间件。 stackoverflow.com/a/24460462/2368836

标签： python selenium web-scraping scrapy scrapyd

【解决方案1】：

导入SignalManager:

from scrapy.signalmanager import SignalManager

然后替换：

dispatcher.connect(self.spider_closed, signals.spider_closed)

与：

SignalManager(dispatcher.Any).connect(self.spider_closed, signal=signals.spider_closed)

【讨论】：

【解决方案2】：

你试过在蜘蛛上实现 from_crawler 吗？我只在管道和扩展上做过这个，但它应该对蜘蛛同样有效..

@classmethod
def from_crawler(cls, crawler, *args, **kwargs):
    o = cls(*args, **kwargs)
    crawler.signals.connect(o.spider_closed, signal=signals.spider_closed)
    return o

http://doc.scrapy.org/en/latest/topics/spiders.html#scrapy.spiders.Spider.from_crawler

【讨论】：