我正在使用scrapy爬行我的站点地图，以检查404、302和200页。但是我似乎无法获得响应代码。到目前为止，这是我的代码：

from scrapy.contrib.spiders import SitemapSpider


class TothegoSitemapHomesSpider(SitemapSpider):
    name ='tothego_homes_spider'

    ## robe che ci servono per tothego ##
   sitemap_urls = []
   ok_log_file =       '/opt/Workspace/myapp/crawler/valid_output/ok_homes'
   bad_log_file =      '/opt/Workspace/myapp/crawler/bad_homes'
   fourohfour =        '/opt/Workspace/myapp/crawler/404/404_homes'

   def __init__(self, **kwargs):
        SitemapSpider.__init__(self)

        if len(kwargs) > 1:
            if 'domain' in kwargs:
                self.sitemap_urls = ['http://url_to_sitemap%s/sitemap.xml' % kwargs['domain']]

            if 'country' in kwargs:
                self.ok_log_file += "_%s.txt" % kwargs['country']
                self.bad_log_file += "_%s.txt" % kwargs['country']
                self.fourohfour += "_%s.txt" % kwargs['country']

        else:
            print "USAGE: scrapy [crawler_name] -a country=[country] -a domain=[domain] \nWith [crawler_name]:\n- tothego_homes_spider\n- tothego_cars_spider\n- tothego_jobs_spider\n"
            exit(1)

    def parse(self, response):
        try:
            if response.status == 404:
                ## 404 tracciate anche separatamente
                self.append(self.bad_log_file, response.url)
                self.append(self.fourohfour, response.url)

            elif response.status == 200:
                ## printa su ok_log_file
                self.append(self.ok_log_file, response.url)
            else:
                self.append(self.bad_log_file, response.url)

        except Exception, e:
            self.log('[eccezione] : %s' % e)
            pass

    def append(self, file, string):
        file = open(file, 'a')
        file.write(string+"\n")
        file.close()

他们从scrapy的文档中说，response.status参数是一个整数，对应于响应的状态码。到目前为止，它仅记录200个状态URL，而302未记录在输出文件中（但我可以在crawl.log中看到重定向）。那么，我该怎么做才能“捕获” 302请求并保存这些URL？