通过本文主要向大家介绍了scrapy,scrapy安装,scrapy教程,scrapy中文文档,python scrapy等相关知识,希望对您有所帮助,也希望大家支持linkedu.com www.linkedu.com
本文实例讲述了基于scrapy实现的简单蜘蛛采集程序。分享给大家供大家参考。具体如下：
# 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')]
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希望本文所述对大家的Python程序设计有所帮助。
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