scrapy: Call a function when a spider quits

Question

Is there a way to trigger a method in a Spider class just before it terminates?

I can terminate the spider myself, like this:

class MySpider(CrawlSpider):
    #Config stuff goes here...

    def quit(self):
        #Do some stuff...
        raise CloseSpider('MySpider is quitting now.')

    def my_parser(self, response):
        if termination_condition:
            self.quit()

        #Parsing stuff goes here...

But I can't find any information on how to determine when the spider is about to quit naturally.

Answer 1

It looks like you can register a signal listener through dispatcher.

I would try something like:

from scrapy import signals
from scrapy.xlib.pydispatch import dispatcher

class MySpider(CrawlSpider):
    def __init__(self):
        dispatcher.connect(self.spider_closed, signals.spider_closed)

    def spider_closed(self, spider):
      # second param is instance of spder about to be closed.

---

In the newer version of scrapy scrapy.xlib.pydispatch is deprecated. instead you can use from pydispatch import dispatcher.