python定向爬虫校园论坛帖子信息

Python  /  管理员 发布于 7年前   226

引言

写这个小爬虫主要是为了爬校园论坛上的实习信息，主要采用了Requests库

源码

URLs.py

主要功能是根据一个初始url（包含page页面参数）来获得page页面从当前页面数到pageNum的url列表

import redef getURLs(url, attr, pageNum=1):  all_links = []  try:    now_page_number = int(re.search(attr+'=(\d+)', url, re.S).group(1))    for i in range(now_page_number, pageNum + 1):      new_url = re.sub(attr+'=\d+', attr+'=%s' % i, url, re.S)      all_links.append(new_url)    return all_links  except TypeError:    print "arguments TypeError:attr should be string."

uni_2_native.py

由于论坛上爬取得到的网页上的中文都是unicode编码的形式，文本格式都为 &#XXXX;的形式，所以在爬得网站内容后还需要对其进行转换

import sysimport rereload(sys)sys.setdefaultencoding('utf-8')def get_native(raw):  tostring = raw  while True:    obj = re.search('&#(.*?);', tostring, flags=re.S)    if obj is None:      break    else:      raw, code = obj.group(0), obj.group(1)      tostring = re.sub(raw, unichr(int(code)), tostring)  return tostring

存入SQLite数据库：saveInfo.py

# -*- coding: utf-8 -*-import MySQLdbclass saveSqlite():  def __init__(self):    self.infoList = []  def saveSingle(self, author=None, title=None, date=None, url=None,reply=0, view=0):    if author is None or title is None or date is None or url is None:      print "No info saved!"    else:      singleDict = {}      singleDict['author'] = author      singleDict['title'] = title      singleDict['date'] = date      singleDict['url'] = url      singleDict['reply'] = reply      singleDict['view'] = view      self.infoList.append(singleDict)  def toMySQL(self):    conn = MySQLdb.connect(host='localhost', user='root', passwd='', port=3306, db='db_name', charset='utf8')    cursor = conn.cursor()    # sql = "select * from info"    # n = cursor.execute(sql)    # for row in cursor.fetchall():    #   for r in row:    #     print r    #   print '\n'    sql = "delete from info"    cursor.execute(sql)    conn.commit()    sql = "insert into info(title,author,url,date,reply,view) values (%s,%s,%s,%s,%s,%s)"    params = []    for each in self.infoList:      params.append((each['title'], each['author'], each['url'], each['date'], each['reply'], each['view']))    cursor.executemany(sql, params)    conn.commit()    cursor.close()    conn.close()  def show(self):    for each in self.infoList:      print "author: "+each['author']      print "title: "+each['title']      print "date: "+each['date']      print "url: "+each['url']      print "reply: "+str(each['reply'])      print "view: "+str(each['view'])      print '\n'if __name__ == '__main__':  save = saveSqlite()  save.saveSingle('网','aaa','2008-10-10 10:10:10','www.baidu.com',1,1)  # save.show()  save.toMySQL()

主要爬虫代码

import requestsfrom lxml import etreefrom cc98 import uni_2_native, URLs, saveInfo# 根据自己所需要爬的网站，伪造一个headerheaders ={  'Accept': '',  'Accept-Encoding': '',  'Accept-Language': '',  'Connection': '',  'Cookie': '',  'Host': '',  'Referer': '',  'Upgrade-Insecure-Requests': '',  'User-Agent': ''}url = 'http://www.cc98.org/list.asp?boardid=459&page=1&action='cc98 = 'http://www.cc98.org/'print "get infomation from cc98..."urls = URLs.getURLs(url, "page", 50)savetools = saveInfo.saveSqlite()for url in urls:  r = requests.get(url, headers=headers)  html = uni_2_native.get_native(r.text)  selector = etree.HTML(html)  content_tr_list = selector.xpath('//form/table[@class="tableborder1 list-topic-table"]/tbody/tr')  for each in content_tr_list:    href = each.xpath('./td[2]/a/@href')    if len(href) == 0:      continue    else:      # print len(href)      # not very well using for, though just one element in list      # but I don't know why I cannot get the data by index      for each_href in href:        link = cc98 + each_href      title_author_time = each.xpath('./td[2]/a/@title')      # print len(title_author_time)      for info in title_author_time:        info_split = info.split('\n')        title = info_split[0][1:len(info_split[0])-1]        author = info_split[1][3:]        date = info_split[2][3:]      hot = each.xpath('./td[4]/text()')      # print len(hot)      for hot_num in hot:        reply_view = hot_num.strip().split('/')        reply, view = reply_view[0], reply_view[1]      savetools.saveSingle(author=author, title=title, date=date, url=link, reply=reply, view=view)print "All got! Now saving to Database..."# savetools.show()savetools.toMySQL()print "ALL CLEAR! Have Fun!"

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