python抓取百度贴吧的帖子代码
python备忘

# -*- coding:utf-8 -*- import urllib import urllib2 import re # 处理页面标签类 class Tool: # 去除img标签,7位长空格 removeImg = re.compile('<img.*?>| {7}|') # 删除超链接标签 removeAddr = re.compile('<a.*?>|</a>') # 把换行的标签换为\n replaceLine = re.compile('<tr>|<div>|</div>|</p>') # 将表格制表<td>替换为\t replaceTD = re.compile('<td>') # 把段落开头换为\n加空两格 replacePara = re.compile('<p.*?>') # 将换行符或双换行符替换为\n replaceBR = re.compile('<br><br>|<br>') # 将其余标签剔除 removeExtraTag = re.compile('<.*?>') def replace(self, x): x = re.sub(self.removeImg, "", x) x = re.sub(self.removeAddr, "", x) x = re.sub(self.replaceLine, "\n", x) x = re.sub(self.replaceTD, "\t", x) x = re.sub(self.replacePara, "\n ", x) x = re.sub(self.replaceBR, "\n", x) x = re.sub(self.removeExtraTag, "", x) # strip()将前后多余内容删除 return x.strip() # 百度贴吧爬虫类 class BDTB: # 初始化,传入基地址,是否只看楼主的参数 def __init__(self, baseUrl, seeLZ, floorTag): # base链接地址 self.baseURL = baseUrl # 是否只看楼主 self.seeLZ = '?see_lz=' + str(seeLZ) # HTML标签剔除工具类对象 self.tool = Tool() # 全局file变量,文件写入操作对象 self.file = None # 楼层标号,初始为1 self.floor = 1 # 默认的标题,如果没有成功获取到标题的话则会用这个标题 self.defaultTitle = u"百度贴吧" # 是否写入楼分隔符的标记 self.floorTag = floorTag # 传入页码,获取该页帖子的代码 def getPage(self, pageNum): try: # 构建URL url = self.baseURL + self.seeLZ + '&pn=' + str(pageNum) request = urllib2.Request(url) response = urllib2.urlopen(request) # 返回UTF-8格式编码内容 return response.read().decode('utf-8') # 无法连接,报错 except urllib2.URLError, e: if hasattr(e, "reason"): print u"连接百度贴吧失败,错误原因", e.reason return None # 获取帖子标题 def getTitle(self, page): # 得到标题的正则表达式 pattern = re.compile('<h1 class="core_title_txt.*?>(.*?)</h1>', re.S) result = re.search(pattern, page) if result: # 如果存在,则返回标题 return result.group(1).strip() else: return None # 获取帖子一共有多少页 def getPageNum(self, page): # 获取帖子页数的正则表达式 pattern = re.compile('<li class="l_reply_num.*?</span>.*?<span.*?>(.*?)</span>', re.S) result = re.search(pattern, page) if result: return result.group(1).strip() else: return None # 获取每一层楼的内容,传入页面内容 def getContent(self, page): # 匹配所有楼层的内容 pattern = re.compile('<div id="post_content_.*?>(.*?)</div>', re.S) items = re.findall(pattern, page) contents = [] for item in items: # 将文本进行去除标签处理,同时在前后加入换行符 content = "\n" + self.tool.replace(item) + "\n" contents.append(content.encode('utf-8')) return contents def setFileTitle(self, title): # 如果标题不是为None,即成功获取到标题 if title is not None: self.file = open(title + ".txt", "w+") else: self.file = open(self.defaultTitle + ".txt", "w+") def writeData(self, contents): # 向文件写入每一楼的信息 for item in contents: if self.floorTag == '1': # 楼之间的分隔符 floorLine = "\n" + str( self.floor) + u"-----------------------------------------------------------------------------------------\n" self.file.write(floorLine) self.file.write(item) self.floor += 1 def start(self): indexPage = self.getPage(1) pageNum = self.getPageNum(indexPage) title = self.getTitle(indexPage) self.setFileTitle(title) if pageNum == None: print "URL已失效,请重试" return try: print "该帖子共有" + str(pageNum) + "页" for i in range(1, int(pageNum) + 1): print "正在写入第" + str(i) + "页数据" page = self.getPage(i) contents = self.getContent(page) self.writeData(contents) # 出现写入异常 except IOError, e: print "写入异常,原因" + e.message finally: print "写入任务完成" print u"请输入帖子代号" baseURL = 'http://tieba.baidu.com/p/' + str(raw_input(u'http://tieba.baidu.com/p/')) seeLZ = raw_input("是否只获取楼主发言,是输入1,否输入0\n") floorTag = raw_input("是否写入楼层信息,是输入1,否输入0\n") bdtb = BDTB(baseURL, seeLZ, floorTag) bdtb.start()