使用 scrapy 爬新浪微博，发现网页被重定向之后没法进入自定义的解析函数了，怎么回事呢？

爬其他的 URL 都可以啊，是因为新浪微博被重定向的原因吗？

import scrapy
import re 
from scrapy.selector import Selector
from scrapy.http import Request
from tutorial.items import DmozItem
from string import maketrans
from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.contrib.linkextractors import LinkExtractor
def extractData(regex, content, index=1): 
    r = '0' 
    p = re.compile(regex) 
    m = p.search(content) 
    if m: 
        r = m.group(index) 
    return r 
class DmozSpider(CrawlSpider):
    name = "dmoz"
    allowed_domains = ["weibo.com"]
    download_delay = 2
    rules=[
        Rule(LinkExtractor(allow=('/')),callback='parse_item',follow=True)
        ]

    headers = {
        "Accept": "*/*",
        "Accept-Encoding": "gzip, deflate, sdch, br",
        "Accept-Language": "zh-CN,zh;q=0.8",
        "Connection": "keep-alive",
        # "Host": "login.sina.com.cn",
        "Referer": "http://weibo.com/",
        "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.75 Safari/537.36"
    }
    cookies = {
        'ALF':'我的 cookie',
        'Apache':'我的 cookie',
        'SCF':'我的 cookie',
        'SINAGLOBAL':'我的 cookie',
        'SSOLoginState':'我的 cookie',
        'SUB':'我的 cookie',
        'SUBP':'我的 cookie',
        'SUHB':'我的 cookie',
        'TC-Page-G0':'我的 cookie',
        'TC-Ugrow-G0':'我的 cookie',
        'TC-V5-G0':'我的 cookie',
        'ULV':'我的 cookie',
        'UOR':'我的 cookie',
        'WBStorage':'我的 cookie',
        'YF-Page-G0':'我的 cookie',
        'YF-Ugrow-G0':'我的 cookie',
        'YF-V5-G0':'我的 cookie',
        '_s_tentry':'-',
        'log_sid_t':'我的 cookie',
        'un':'我的 cookie',
    }
    def start_requests(self):
        return [Request("http://weibo.com/u/2010226570?refer_flag=1001030101_&is_all=1",cookies = self.cookies,headers=self.headers)]

    def parse_item(self, response):
        print "comehere!"
        regexID=r'class=\\"username\\">(.*)\<\\/h1>'
        content=response.body
        item=DmozItem()
        ID=extractData(regexID,content,1)
        item['ID']=ID
        print ID       
        yield item

控制台输出如下：

2017-01-08 17:51:34 [scrapy.core.engine] INFO: Spider opened
2017-01-08 17:51:34 [scrapy.extensions.logstats] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)
2017-01-08 17:51:34 [scrapy.extensions.telnet] DEBUG: Telnet console listening on 127.0.0.1:6023
2017-01-08 17:51:46 [scrapy.downloadermiddlewares.redirect] DEBUG: Redirecting (302) to <GET http://login.sina.com.cn/sso/login.php?url=http%3A%2F%2Fweibo.com%2Fu%2F2010226570%3Frefer_flag%3D1001030101_%26is_all%3D1&_rand=1483869098.691&gateway=1&service=miniblog&entry=miniblog&useticket=1&returntype=META&sudaref=http%3A%2F%2Fweibo.com%2F&_client_version=0.6.23> from <GET http://weibo.com/u/2010226570?refer_flag=1001030101_&is_all=1>
2017-01-08 17:51:47 [scrapy.downloadermiddlewares.redirect] DEBUG: Redirecting (meta refresh) to <GET http://weibo.com/u/2010226570?refer_flag=1001030101_&is_all=1&sudaref=weibo.com&retcode=6102> from <GET http://login.sina.com.cn/sso/login.php?url=http%3A%2F%2Fweibo.com%2Fu%2F2010226570%3Frefer_flag%3D1001030101_%26is_all%3D1&_rand=1483869098.691&gateway=1&service=miniblog&entry=miniblog&useticket=1&returntype=META&sudaref=http%3A%2F%2Fweibo.com%2F&_client_version=0.6.23>
2017-01-08 17:51:49 [scrapy.core.engine] DEBUG: Crawled (200) <GET http://weibo.com/u/2010226570?refer_flag=1001030101_&is_all=1&sudaref=weibo.com&retcode=6102> (referer: http://weibo.com/)
2017-01-08 17:51:49 [scrapy.core.engine] INFO: Closing spider (finished)