如果你希望在一个写好的程序里调用scrapy，就可以通过下面的代码，让scrapy运行在一个线程里。

# When you run the Scrapy crawler from a program, the code blocks until the Scrapy crawler is finished. This is due to how Twisted (the underlying asynchronous network library) works. This prevents using the Scrapy crawler from scripts or other code.  #  # To circumvent this issue you can run the Scrapy crawler in a thread with this code.  #  # Keep in mind that this code is mainly for illustrative purposes and far from production ready.  #  # Also the code was only tested with Scrapy 0.8, and will probably need some adjustments for newer versions (since the core API isn't stable yet), but you get the idea.      """  Code to run Scrapy crawler in a thread - works on Scrapy 0.8  """      import threading, Queue      from twisted.internet import reactor      from scrapy.xlib.pydispatch import dispatcher  from scrapy.core.manager import scrapymanager  from scrapy.core.engine import scrapyengine  from scrapy.core import signals      class CrawlerThread(threading.Thread):          def __init__(self):          threading.Thread.__init__(self)          self.running = False          def run(self):          self.running = True          scrapymanager.configure(control_reactor=False)          scrapymanager.start()          reactor.run(installSignalHandlers=False)          def crawl(self, *args):          if not self.running:              raise RuntimeError("CrawlerThread not running")          self._call_and_block_until_signal(signals.spider_closed, \              scrapymanager.crawl, *args)          def stop(self):          reactor.callFromThread(scrapyengine.stop)          def _call_and_block_until_signal(self, signal, f, *a, **kw):          q = Queue.Queue()          def unblock():              q.put(None)          dispatcher.connect(unblock, signal=signal)          reactor.callFromThread(f, *a, **kw)          q.get()          # Usage example below:      import os  os.environ.setdefault('SCRAPY_SETTINGS_MODULE', 'myproject.settings')      from scrapy.xlib.pydispatch import dispatcher  from scrapy.core import signals  from scrapy.conf import settings  from scrapy.crawler import CrawlerThread      settings.overrides['LOG_ENABLED'] = False # avoid log noise      def item_passed(item):      print "Just scraped item:", item      dispatcher.connect(item_passed, signal=signals.item_passed)      crawler = CrawlerThread()  print "Starting crawler thread..."  crawler.start()  print "Crawling somedomain.com...."  crawler.crawl('somedomain.com) # blocking call  print "Crawling anotherdomain.com..."  crawler.crawl('anotherdomain.com') # blocking call  print "Stopping crawler thread..."  crawler.stop()