Python 爬虫学习 urllib2

用urllib2抓取被限制的网站页面

1. # coding:utf-8
   
   import urllib2
   
   url = "http://blog.csdn.net/troubleshooter"
   
   html = urllib2.urlopen(url)
   
   print html.read()
   

   　　返回403错误

2. 模拟用户访问

   # coding:utf-8
   
   import urllib2
   
   url = "http://blog.csdn.net/troubleshooter"
   
   url_headers = {'User-Agent':'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/38.0.2125.111 Safari/537.36',
   				'Referer':'http://www.cnblogs.com/evilxr/p/4038902.html',
   				'Host':'blog.csdn.net',
   				'GET':url
   				}
   
   req = urllib2.Request(url, headers=url_headers)
   html = urllib2.urlopen(req)
   print html.getcode()

   200
   [Finished in 0.4s]
   

   　　

3. 获取Cookie信息

   import urllib2
   import cookielib
   
   cookie = cookielib.CookieJar()
   opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cookie))
   response = opener.open('http://www.baidu.com')
   In [12]: for i in cookie:
       print i.name,i.value
      ....:
   BAIDUID 4722B044786BAE8B1E484C0535706271:FG=1
   BIDUPSID 4722B044786BAE8B1E484C0535706271
   H_PS_PSSID 10299_16540_1430_16474_12824_10812_12868_14669_16520_16326_16662_16424_16514_15050_12386_13932
   PSTM 1438398244
   BDSVRTM 0
   BD_HOME 0
   

4. 打开调试功能

   import urllib2
   
   httpHandler = urllib2.HTTPHandler(debuglevel=1)
   httpsHandler = urllib2.HTTPSHandler(debuglevel=1)
   opener = urllib2.build_opener(httpHandler, httpsHandler)
   
   urllib2.install_opener(opener)
   response = urllib2.urlopen('http://www.baidu.com')
   response = urllib2.urlopen('http://www.baidu.com')
   send: 'GET / HTTP/1.1\r\nAccept-Encoding: identity\r\nHost: www.baidu.com\r\nConnection: close\r\nUser-Agent: Python-urllib/2.7\r\n\r\n'
   reply: 'HTTP/1.1 200 OK\r\n'
   header: Date: Sat, 01 Aug 2014 03:14:07 GMT
   header: Content-Type: text/html; charset=utf-8
   header: Transfer-Encoding: chunked
   header: Connection: Close
   header: Vary: Accept-Encoding
   header: Set-Cookie: BAIDUID=0E3FD673DED07D3DBB4D6048AB469A32:FG=1; expires=Thu, 31-Dec-37 23:55:55 GMT; max-age=2147483647; path=/; domain=.baidu.com
   header: Set-Cookie: BIDUPSID=0E3FD673DED07D3DBB4D6048AB469A32; expires=Thu, 31-Dec-37 23:55:55 GMT; max-age=2147483647; path=/; domain=.baidu.com
   header: Set-Cookie: PSTM=1438398847; expires=Thu, 31-Dec-37 23:55:55 GMT; max-age=2147483647; path=/; domain=.baidu.com
   header: Set-Cookie: BDSVRTM=0; path=/
   header: Set-Cookie: BD_HOME=0; path=/
   header: Set-Cookie: H_PS_PSSID=13289_1441_10813_14432_12867_14667_16521_14951_16663_16427_16514_15291_12315_13932_10634; path=/; domain=.baidu.com
   header: P3P: CP=" OTI DSP COR IVA OUR IND COM "
   header: Cache-Control: private
   header: Cxy_all: baidu+d4d7821ea11368a1cad938a4de84b7ab
   header: Expires: Sat, 01 Aug 2015 03:13:12 GMT
   header: X-Powered-By: HPHP
   header: Server: BWS/1.1
   header: X-UA-Compatible: IE=Edge,chrome=1
   header: BDPAGETYPE: 1
   header: BDQID: 0x8824b3dc0001bdbb
   header: BDUSERID: 0