基于scrapy实现的简单蜘蛛采集程序

# Standard Python library imports
# 3rd party imports
from scrapy.contrib.spiders import CrawlSpider, Rule
from scrapy.contrib.linkextractors.sgml import SgmlLinkExtractor
from scrapy.selector import HtmlXPathSelector
# My imports
from poetry_analysis.items import PoetryAnalysisItem
HTML_FILE_NAME = r'.+.html'
class PoetryParser(object):
 """
 Provides common parsing method for poems formatted this one specific way.
 """
 date_pattern = r'(d{2} w{3,9} d{4})'
 
 def parse_poem(self, response):
 hxs = HtmlXPathSelector(response)
 item = PoetryAnalysisItem()
 # All poetry text is in pre tags
 text = hxs.select('//pre/text()').extract()
 item['text'] = ''.join(text)
 item['url'] = response.url
 # head/title contains title - a poem by author
 title_text = hxs.select('//head/title/text()').extract()[0]
 item['title'], item['author'] = title_text.split(' - ')
 item['author'] = item['author'].replace('a poem by', '')
 for key in ['title', 'author']:
 item[key] = item[key].strip()
 item['date'] = hxs.select("//p[@class='small']/text()").re(date_pattern)
 return item
class PoetrySpider(CrawlSpider, PoetryParser):
 name = 'example.com_poetry'
 allowed_domains = ['www.example.com']
 root_path = 'someuser/poetry/'
 start_urls = ['http://www.example.com/someuser/poetry/recent/',
 'http://www.example.com/someuser/poetry/less_recent/']
 rules = [Rule(SgmlLinkExtractor(allow=[start_urls[0] + HTML_FILE_NAME]),
 callback='parse_poem'),
 Rule(SgmlLinkExtractor(allow=[start_urls[1] + HTML_FILE_NAME]),
 callback='parse_poem')]