ReactorNotRestartable错误，如何在for循环中使用scrapy CrawlerProcess

Question

我想用一个子类用不同的url运行我的蜘蛛并通过循环保存信息。这是我的方法：

class Run_Spider_From_SubClass:

def __init__(self, url_list, *args, **kwargs):
    super().__init__(*args, **kwargs)
    self.url_list = url_list


def run_spider_in_loop(self):

    #here I start feeding urls, but more important I can save info for each 
    #crawling process, and then restart the process with another url along
    #loop.

    for url in self.url_list:    
        process = CrawlerProcess(get_project_settings())  # this drive the scrapy to use configuration in 'settings.py', all class must start from this
        process.crawl('MySpider', url)
        process.start()
        save_info  # any codes that save info from spider into target file

在此之后，我遇到反应堆问题：

Traceback (most recent call last):

File "G:/python/test/scrapy_test/test4.py", line 45, in <module>
Run_Spider_From_SubClass(url_list).run_spider_in_loop()

File "G:/python/test/scrapy_test/test4.py", line 34, in run_spider_in_loop
process.start()

File "C:\Users\super\AppData\Roaming\Python\Python36\site- 
packages\scrapy\crawler.py", line 291, in start
reactor.run(installSignalHandlers=False)  # blocking call

File "C:\Users\super\AppData\Roaming\Python\Python36\site- 
packages\twisted\internet\base.py", line 1266, in run
self.startRunning(installSignalHandlers=installSignalHandlers)

File "C:\Users\super\AppData\Roaming\Python\Python36\site- 
packages\twisted\internet\base.py", line 1246, in startRunning
ReactorBase.startRunning(self)

File "C:\Users\super\AppData\Roaming\Python\Python36\site- 
packages\twisted\internet\base.py", line 754, in startRunning
raise error.ReactorNotRestartable()
twisted.internet.error.ReactorNotRestartable

如何克服这个反应堆错误，谢谢。

Answer 1

我不确定你打算在save_info做什么，但这里是一个按顺序多次运行同一个蜘蛛的最小例子。它基于您的类和documentation中的示例：

from twisted.internet import reactor, defer
from scrapy.crawler import CrawlerRunner
from scrapy.utils.log import configure_logging
from scrapy.utils.project import get_project_settings


class Run_Spider_From_SubClass:

    def __init__(self, url_list, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.url_list = url_list

        configure_logging()
        self.runner = CrawlerRunner(get_project_settings())

    @defer.inlineCallbacks
    def crawl(self):
        for url in self.url_list:
            yield self.runner.crawl('MySpider', url=url)
        reactor.stop()

    def run_spider_in_loop(self):
        self.crawl()
        reactor.run()


urls = ['http://something.com', 'http://another.com']
runner = Run_Spider_From_SubClass(urls)
runner.run_spider_in_loop()