Python 在for循环中运行多个spider
我尝试实例化多个spider。第一个很好,但是第二个给了我一个错误:ReactorNotRestartablePython 在for循环中运行多个spider,python,scrapy,twisted,scrapy-spider,Python,Scrapy,Twisted,Scrapy Spider,我尝试实例化多个spider。第一个很好,但是第二个给了我一个错误:ReactorNotRestartable feeds = { 'nasa': { 'name': 'nasa', 'url': 'https://www.nasa.gov/rss/dyn/breaking_news.rss', 'start_urls': ['https://www.nasa.gov/rss/dyn/breaking_news.rss'] },
feeds = {
'nasa': {
'name': 'nasa',
'url': 'https://www.nasa.gov/rss/dyn/breaking_news.rss',
'start_urls': ['https://www.nasa.gov/rss/dyn/breaking_news.rss']
},
'xkcd': {
'name': 'xkcd',
'url': 'http://xkcd.com/rss.xml',
'start_urls': ['http://xkcd.com/rss.xml']
}
}
对于上面的项目,我尝试在一个循环中运行两个spider,如下所示:
from scrapy.crawler import CrawlerProcess
from scrapy.spiders import XMLFeedSpider
class MySpider(XMLFeedSpider):
name = None
def __init__(self, **kwargs):
this_feed = feeds[self.name]
self.start_urls = this_feed.get('start_urls')
self.iterator = 'iternodes'
self.itertag = 'items'
super(MySpider, self).__init__(**kwargs)
def parse_node(self, response, node):
pass
def start_crawler():
process = CrawlerProcess({
'USER_AGENT': CONFIG['USER_AGENT'],
'DOWNLOAD_HANDLERS': {'s3': None} # boto issues
})
for feed_name in feeds.keys():
MySpider.name = feed_name
process.crawl(MySpider)
process.start()
第二个循环的例外情况如下所示,spider已打开,但是:
...
2015-11-22 00:00:00 [scrapy] INFO: Spider opened
2015-11-22 00:00:00 [scrapy] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)
2015-11-22 00:00:00 [scrapy] DEBUG: Telnet console listening on 127.0.0.1:6023
2015-11-21 23:54:05 [scrapy] DEBUG: Telnet console listening on 127.0.0.1:6023
Traceback (most recent call last):
File "env/bin/start_crawler", line 9, in <module>
load_entry_point('feed-crawler==0.0.1', 'console_scripts', 'start_crawler')()
File "/Users/bling/py-feeds-crawler/feed_crawler/crawl.py", line 51, in start_crawler
process.start() # the script will block here until the crawling is finished
File "/Users/bling/py-feeds-crawler/env/lib/python2.7/site-packages/scrapy/crawler.py", line 251, in start
reactor.run(installSignalHandlers=False) # blocking call
File "/usr/local/lib/python2.7/site-packages/twisted/internet/base.py", line 1193, in run
self.startRunning(installSignalHandlers=installSignalHandlers)
File "/usr/local/lib/python2.7/site-packages/twisted/internet/base.py", line 1173, in startRunning
ReactorBase.startRunning(self)
File "/usr/local/lib/python2.7/site-packages/twisted/internet/base.py", line 684, in startRunning
raise error.ReactorNotRestartable()
twisted.internet.error.ReactorNotRestartable
。。。
2015-11-22 00:00:00[scrapy]信息:蜘蛛打开
2015-11-22 00:00:00[scrapy]信息:爬网0页(以0页/分钟的速度),刮取0项(以0项/分钟的速度)
2015-11-22 00:00:00[scrapy]调试:Telnet控制台监听127.0.0.1:6023
2015-11-21 23:54:05[scrapy]调试:Telnet控制台监听127.0.0.1:6023
回溯(最近一次呼叫最后一次):
文件“env/bin/start_crawler”,第9行,在
加载入口点('feed-crawler==0.0.1','console\u scripts','start\u crawler')()
文件“/Users/bling/py feeds crawler/feed\u crawler/crawl.py”,第51行,在start\u crawler中
process.start()#脚本将在此处阻塞,直到爬网完成
文件“/Users/bling/py feeds crawler/env/lib/python2.7/site packages/scrapy/crawler.py”,第251行,在开始处
reactor.run(installSignalHandlers=False)#阻止调用
文件“/usr/local/lib/python2.7/site packages/twisted/internet/base.py”,第1193行,运行中
self.startRunning(installSignalHandlers=installSignalHandlers)
文件“/usr/local/lib/python2.7/site packages/twisted/internet/base.py”,第1173行,在startRunning中
反应器基础启动耳轴(自)
文件“/usr/local/lib/python2.7/site packages/twisted/internet/base.py”,第684行,在startRunning中
引发错误。ReactorNotRestartable()
twisted.internet.error.ReactorNotRestartable
我是否必须让第一个神秘感失效,或者我做错了什么,需要改变它的工作原理。提前感谢。看起来您必须为每个spider实例化一个进程,请尝试:
def start_crawler():
for feed_name in feeds.keys():
process = CrawlerProcess({
'USER_AGENT': CONFIG['USER_AGENT'],
'DOWNLOAD_HANDLERS': {'s3': None} # boto issues
})
MySpider.name = feed_name
process.crawl(MySpider)
process.start()
解决方案是收集循环中的爬行器,并在结束时只启动一次进程。我猜,这与反应堆分配/解除分配有关
def start_crawler():
process = CrawlerProcess({
'USER_AGENT': CONFIG['USER_AGENT'],
'DOWNLOAD_HANDLERS': {'s3': None} # disable for issues with boto
})
for feed_name in CONFIG['Feeds'].keys():
MySpider.name = feed_name
process.crawl(MySpider)
process.start()
感谢@eLRuLL的回答,它启发我找到了这个解决方案。您可以在爬网中发送参数,并在解析过程中使用它们
class MySpider(XMLFeedSpider):
def __init__(self, name, **kwargs):
super(MySpider, self).__init__(**kwargs)
self.name = name
def start_crawler():
process = CrawlerProcess({
'USER_AGENT': CONFIG['USER_AGENT'],
'DOWNLOAD_HANDLERS': {'s3': None} # boto issues
})
for feed_name in feeds.keys():
process.crawl(MySpider, feed_name)
process.start()
这确实更有意义,但仍然是一个例外。