Scrapy retry or redirect middleware

Question

While crawling through a site with scrapy, I get redirected to a user-blocked page about 1/5th of the time. I lose the pages that I get redirected from when that happe

Answer 1

I had the same problem today with a website that used 301..303 redirects, but also sometimes meta redirect. I've build a retry middleware and used some chunks from the redirect middlewares:

from scrapy.contrib.downloadermiddleware.retry import RetryMiddleware
from scrapy.selector import HtmlXPathSelector
from scrapy.utils.response import get_meta_refresh
from scrapy import log

class CustomRetryMiddleware(RetryMiddleware):

    def process_response(self, request, response, spider):
        url = response.url
        if response.status in [301, 307]:
            log.msg("trying to redirect us: %s" %url, level=log.INFO)
            reason = 'redirect %d' %response.status
            return self._retry(request, reason, spider) or response
        interval, redirect_url = get_meta_refresh(response)
        # handle meta redirect
        if redirect_url:
            log.msg("trying to redirect us: %s" %url, level=log.INFO)
            reason = 'meta'
            return self._retry(request, reason, spider) or response
        hxs = HtmlXPathSelector(response)
        # test for captcha page
        captcha = hxs.select(".//input[contains(@id, 'captchacharacters')]").extract()
        if captcha:
            log.msg("captcha page %s" %url, level=log.INFO)
            reason = 'capcha'
            return self._retry(request, reason, spider) or response
        return response

In order to use this middleware it's probably best to disable the exiting redirect middlewares for this project in settings.py:

DOWNLOADER_MIDDLEWARES = {
                         'YOUR_PROJECT.scraper.middlewares.CustomRetryMiddleware': 120,
                          'scrapy.contrib.downloadermiddleware.redirect.RedirectMiddleware': None,
                          'scrapy.contrib.downloadermiddleware.redirect.MetaRefreshMiddleware': None,
}