Python中使用urllib2防止302跳转的代码例子

说明：python的urllib2获取网页(urlopen)会自动重定向（301,302）。但是，有时候我们需要获取302,301页面的状态信息。就必须获取到转向前的调试信息。

下面代码将可以做到避免302重定向到新的网页

    #!/usr/bin/python
    # -*- coding: utf-8 -*-
    #encoding=utf-8
    #Filename:states_code.py

    import urllib2

    class RedirctHandler(urllib2.HTTPRedirectHandler):
      """docstring for RedirctHandler"""
      def http_error_301(self, req, fp, code, msg, headers):
        pass
      def http_error_302(self, req, fp, code, msg, headers):
        pass

    def getUnRedirectUrl(url,timeout=10):
      req = urllib2.Request(url)
      debug_handler = urllib2.HTTPHandler(debuglevel = 1)
      opener = urllib2.build_opener(debug_handler, RedirctHandler)

      html = None
      response = None
      try:
        response = opener.open(url,timeout=timeout)
        html = response.read()
      except urllib2.URLError as e:
        if hasattr(e, 'code'):
          error_info = e.code
        elif hasattr(e, 'reason'):
          error_info = e.reason
      finally:
        if response:
          response.close()
      if html:
        return html
      else:
        return error_info

    html = getUnRedirectUrl('http://jb51.net')
    print html