python - Scrapy蜘蛛不保存html文件

Question

我有一个我生成的 Scrapy 蜘蛛。蜘蛛程序的目的是为了绘制网络图而返回网络数据，并返回蜘蛛程序到达的每个页面的 html 文件。蜘蛛正在实现第一个目标，但没有实现第二个目标。它会生成一个包含跟踪信息的 csv 文件，但我看不到它正在保存 html 文件。

# -*- coding: utf-8 -*-
from scrapy.selector import HtmlXPathSelector
from scrapy.linkextractors import LinkExtractor
from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.utils.url import urljoin_rfc
from sitegraph.items import SitegraphItem


class CrawlSpider(CrawlSpider):
    name = "example"
    custom_settings = {
    'DEPTH_LIMIT': '1',
    }
    allowed_domains = []
    start_urls = (
        'http://exampleurl.com',
    )

    rules = (
        Rule(LinkExtractor(allow=r'/'), callback='parse_item', follow=True),
    )

    def parse_item(self, response):
        hxs = HtmlXPathSelector(response)
        i = SitegraphItem()
        i['url'] = response.url
        # i['http_status'] = response.status
        llinks=[]
        for anchor in hxs.select('//a[@href]'):
            href=anchor.select('@href').extract()[0]
            if not href.lower().startswith("javascript"):
                llinks.append(urljoin_rfc(response.url,href))
        i['linkedurls'] = llinks
        return i

    def parse(self, response):
        filename = response.url.split("/")[-1] + '.html'
        with open(filename, 'wb') as f:
            f.write(response.body)

我收到的回溯如下:

Traceback (most recent call last):
  File "...\Anaconda3\lib\site-packages\scrapy\core\downloader\middleware.py", line 43, in process_request
    defer.returnValue((yield download_func(request=request,spider=spider)))
twisted.internet.error.TCPTimedOutError: TCP connection timed out: 10060: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond..
2019-07-23 14:16:41 [scrapy.downloadermiddlewares.retry] DEBUG: Gave up retrying <GET http://externalurl.com/> (failed 3 times): TCP connection timed out: 10060: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond..
2019-07-23 14:16:41 [scrapy.core.scraper] ERROR: Error downloading <GET http://externalurl.com/>
Traceback (most recent call last):
  File "...\Anaconda3\lib\site-packages\scrapy\core\downloader\middleware.py", line 43, in process_request
    defer.returnValue((yield download_func(request=request,spider=spider)))
twisted.internet.error.TCPTimedOutError: TCP connection timed out: 10060: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond..
2019-07-23 14:16:41 [scrapy.core.engine] INFO: Closing spider (finished)
2019-07-23 14:16:41 [scrapy.extensions.feedexport] INFO: Stored csv feed (153 items) in: exampledomainlevel1.csv

Answer 1

解析方法:

根据scrapy docs和 another stack overflow question不建议重写 parse 方法，因为crawlspider 使用它来实现其逻辑。

如果您需要重写parse方法并同时使用

进行计数

Crawlspider.parse original source code - 您需要添加它的原始源来修复 parse 方法:

def parse(self, response):
    filename = response.url.split("/")[-1] + '.html'
    with open(filename, 'wb') as f:
        f.write(response.body)
    return self._parse_response(response, self.parse_start_url, cb_kwargs={}, follow=True)

csv feed:
该日志行: 2019-07-23 14:16:41 [scrapy.extensions.feedexport] INFO: Stored csv feed (153 items) in: exampledomainlevel1.csv - 意味着 csv feedexporter启用(可能在 settings.py 项目设置文件中。)

更新
我又观察了Crawlspider源码。
看起来 parse 方法在开始时仅调用一次，并且不覆盖所有网络响应。
如果我的理论正确 - 将此函数添加到您的蜘蛛类后应该保存所有 html 响应:

def _response_downloaded(self, response):
    filename = response.url.split("/")[-1] + '.html'
    with open(filename, 'wb') as f:
        f.write(response.body)    
    rule = self._rules[response.meta['rule']]
    return self._parse_response(response, rule.callback, rule.cb_kwargs, rule.follow)