一个简单的python爬虫,爬取知乎

时间:2022-05-11 17:41:06

一个简单的python爬虫,爬取知乎

  • 主要实现 爬取一个收藏夹 里 所有问题答案下的 图片
  • 文字信息暂未收录,可自行实现,比图片更简单
  • 具体代码里有详细注释,请自行阅读

一个简单的python爬虫,爬取知乎

项目源码:

 # -*- coding:utf-8 -*-

 from spider import SpiderHTML
from multiprocessing import Pool
import sys,urllib,http,os,random,re,time
__author__ = 'waiting'
'''
使用了第三方的类库 BeautifulSoup4,请自行安装
需要目录下的spider.py文件
运行环境:python3.4,windows7
''' #收藏夹的地址
url = 'https://www.zhihu.com/collection/30822111' #page参数改为代码添加 #本地存放的路径,不存在会自动创建
store_path = 'E:\\zhihu\收藏夹\\会员才知道的世界' class zhihuCollectionSpider(SpiderHTML):
def __init__(self,pageStart, pageEnd, url):
self._url = url
self._pageStart = int(pageStart)
self._pageEnd = int(pageEnd)+1
self.downLimit = 0 #低于此赞同的答案不收录 def start(self):
for page in range(self._pageStart,self._pageEnd): #收藏夹的页数
url = self._url + '?page='+str(page)
content = self.getUrl(url)
questionList = content.find_all('div',class_='zm-item')
for question in questionList: #收藏夹的每个问题
Qtitle = question.find('h2',class_='zm-item-title')
if Qtitle is None: #被和谐了
continue questionStr = Qtitle.a.string
Qurl = 'https://www.zhihu.com'+Qtitle.a['href'] #问题题目
Qtitle = re.sub(r'[\\/:*?"<>]','#',Qtitle.a.string) #windows文件/目录名不支持的特殊符号
try:
print('-----正在获取问题:'+Qtitle+'-----') #获取到问题的链接和标题,进入抓取
except UnicodeEncodeError:
print(r'---问题含有特殊字符无法显示---')
try:
Qcontent = self.getUrl(Qurl)
except:
print('!!!!获取出错!!!!!')
pass
answerList = Qcontent.find_all('div',class_='zm-item-answer zm-item-expanded')
self._processAnswer(answerList,Qtitle) #处理问题的答案
time.sleep(5) def _processAnswer(self,answerList,Qtitle):
j = 0
for answer in answerList:
j = j + 1 upvoted = int(answer.find('span',class_='count').string.replace('K','')) #获得此答案赞同数
if upvoted < self.downLimit:
continue
authorInfo = answer.find('div',class_='zm-item-answer-author-info') #获取作者信息
author = {'introduction':'','link':''}
try:
author['name'] = authorInfo.find('a',class_='author-link').string #获得作者的名字
author['introduction'] = str(authorInfo.find('span',class_='bio')['title']) #获得作者的简介
author['link'] = authorInfo.find('a',class_='author-link')['href']
except AttributeError:
author['name'] = '匿名用户'+str(j)
except TypeError: #简介为空的情况
pass #匿名用户没有链接 file_name = os.path.join(store_path,Qtitle,'info',author['name']+'_info.txt')
if os.path.exists(file_name): #已经抓取过
continue self.saveText(file_name,'{introduction}\r\n{link}'.format(**author)) #保存作者的信息
print('正在获取用户`{name}`的答案'.format(**author))
answerContent = answer.find('div',class_='zm-editable-content clearfix')
if answerContent is None: #被举报的用户没有答案内容
continue imgs = answerContent.find_all('img')
if len(imgs) == 0: #答案没有上图
pass
else:
self._getImgFromAnswer(imgs,Qtitle,**author) #收录图片
def _getImgFromAnswer(self,imgs,Qtitle,**author):
i = 0
for img in imgs:
if 'inline-image' in img['class']: #不抓取知乎的小图
continue
i = i + 1
imgUrl = img['src']
extension = os.path.splitext(imgUrl)[1]
path_name = os.path.join(store_path,Qtitle,author['name']+'_'+str(i)+extension)
try:
self.saveImg(imgUrl,path_name) #捕获各种图片异常,流程不中断
except:
pass #收录文字
def _getTextFromAnswer(self):
pass #命令行下运行,例:zhihu.py 1 5 获取1到5页的数据
if __name__ == '__main__':
page, limit, paramsNum= 1, 0, len(sys.argv)
if paramsNum>=3:
page, pageEnd = sys.argv[1], sys.argv[2]
elif paramsNum == 2:
page = sys.argv[1]
pageEnd = page
else:
page,pageEnd = 1,1 spider = zhihuCollectionSpider(page,pageEnd,url)
spider.start()

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