Scrapy 里的 rules 完全不生效，这是怎么回事？

Question

代码如下：

from scrapy.selector import Selector
from scrapy.spiders import CrawlSpider, Rule
from scrapy.linkextractors import LinkExtractor
from scrapy import Request
from newspider.items import NewspiderItem



class DatamsgSpider(CrawlSpider):
    """docstring for DatamsgSpider"""
    name = 'milspider'

    def __init__(self,*args,**kwargs):
        super().__init__(*args,**kwargs)

        self.start_urls = ["http://news.xinhuanet.com/mil/index.htm"]

        self.rules = (
        Rule(LinkExtractor(allow=(),
            restrict_xpaths=('//a[@href]')),
            callback='parse_item',
            follow=True)
        )

    def parse_item(self,response):
        url = response.url
        print(url)
        repck = "http://news.xinhuanet.com/mil/"
        if repck in url:
            yield Request(url,callback = self.parse_link)
        else:
            pass
        
    
    def parse_link(self,response):
        data = NewspiderItem()
        #一些提取操作
        return data

我想顺着每个页面，爬取全站的链接，但是运行后结果却是

2017-10-23 11:55:27 [scrapy.utils.log] INFO: Scrapy 1.3.3 started (bot: newspider)
2017-10-23 11:55:27 [scrapy.utils.log] INFO: Overridden settings: {'BOT_NAME': 'newspider', 'COMMANDS_MODULE': 'newspider.commands', 'CONCURRENT_REQUESTS': 50, 'DOWNLOAD_DELAY': 1, 'DOWNLOAD_TIMEOUT': 15, 'LOG_LEVEL': 'INFO', 'NEWSPIDER_MODULE': 'newspider.spiders', 'SPIDER_MODULES': ['newspider.spiders']}

2017-10-23 11:55:27 [scrapy.middleware] INFO: Enabled extensions:
['scrapy.extensions.corestats.CoreStats',
 'scrapy.extensions.telnet.TelnetConsole',
 'scrapy.extensions.logstats.LogStats']
2017-10-23 11:55:27 [scrapy.middleware] INFO: Enabled downloader middlewares:
['scrapy.downloadermiddlewares.httpauth.HttpAuthMiddleware',
 'scrapy.downloadermiddlewares.downloadtimeout.DownloadTimeoutMiddleware',
 'scrapy.downloadermiddlewares.defaultheaders.DefaultHeadersMiddleware',
 'scrapy.downloadermiddlewares.useragent.UserAgentMiddleware',
 'scrapy.downloadermiddlewares.retry.RetryMiddleware',
 'scrapy.downloadermiddlewares.redirect.MetaRefreshMiddleware',
 'scrapy.downloadermiddlewares.httpcompression.HttpCompressionMiddleware',
 'scrapy.downloadermiddlewares.redirect.RedirectMiddleware',
 'scrapy.downloadermiddlewares.cookies.CookiesMiddleware',
 'scrapy.downloadermiddlewares.stats.DownloaderStats']
2017-10-23 11:55:27 [scrapy.middleware] INFO: Enabled spider middlewares:
['scrapy.spidermiddlewares.httperror.HttpErrorMiddleware',
 'scrapy.spidermiddlewares.offsite.OffsiteMiddleware',
 'scrapy.spidermiddlewares.referer.RefererMiddleware',
 'scrapy.spidermiddlewares.urllength.UrlLengthMiddleware',
 'scrapy.spidermiddlewares.depth.DepthMiddleware']
2017-10-23 11:55:27 [scrapy.middleware] INFO: Enabled item pipelines:
['newspider.pipelines.NewspiderPipeline']
2017-10-23 11:55:27 [scrapy.core.engine] INFO: Spider opened
2017-10-23 11:55:27 [scrapy.extensions.logstats] INFO: Crawled 0 pages (at 0 pages/min), scraped 0 items (at 0 items/min)

2017-10-23 11:55:28 [scrapy.core.engine] INFO: Closing spider (finished)
2017-10-23 11:55:28 [scrapy.statscollectors] INFO: Dumping Scrapy stats:
{'downloader/request_bytes': 476,
 'downloader/request_count': 1,
 'downloader/request_method_count/GET': 1,
 'downloader/response_bytes': 14346,
 'downloader/response_count': 1,
 'downloader/response_status_count/200': 1,
 'finish_reason': 'finished',
 'finish_time': datetime.datetime(2017, 10, 23, 3, 55, 28, 109821),
 'log_count/INFO': 13,
 'response_received_count': 1,
 'scheduler/dequeued': 1,
 'scheduler/dequeued/memory': 1,
 'scheduler/enqueued': 1,
 'scheduler/enqueued/memory': 1,
 'start_time': datetime.datetime(2017, 10, 23, 3, 55, 27, 968207)}
2017-10-23 11:55:28 [scrapy.core.engine] INFO: Spider closed (finished)
2017-10-23 11:55:28 [scrapy.core.engine] INFO: Closing spider (finished)
2017-10-23 11:55:28 [scrapy.statscollectors] INFO: Dumping Scrapy stats:
{'downloader/request_bytes': 472,
 'downloader/request_count': 1,
 'downloader/request_method_count/GET': 1,
 'downloader/response_bytes': 29402,
 'downloader/response_count': 1,
 'downloader/response_status_count/200': 1,
 'finish_reason': 'finished',
 'finish_time': datetime.datetime(2017, 10, 23, 3, 55, 28, 116144),
 'log_count/INFO': 10,
 'response_received_count': 1,
 'scheduler/dequeued': 1,
 'scheduler/dequeued/memory': 1,
 'scheduler/enqueued': 1,
 'scheduler/enqueued/memory': 1,
 'start_time': datetime.datetime(2017, 10, 23, 3, 55, 27, 975791)}
2017-10-23 11:55:28 [scrapy.core.engine] INFO: Spider closed (finished)

rules 根本没有生效，没有走 callback 函数，这是怎么回事？怎么办？

Answer 1

我用scrapy shell测试了下，xpath没啥问题，流程应该也没问题，也许是xpath之后需要加点处理？

类似这样url = 'https://zh.airbnb.com' + sel.xpath('@href').extract()[0]