1

我有以下网址

http://bit.ly/cDdh1c

当您将上述网址放在浏览器中并按回车键时，它将重定向到以下网址 http://www.kennystopproducts.info/Top/?hop=arnishad

但是，当我尝试通过 python 程序（在下面你可以看到代码）找到相同的上述 url http://bit.ly/cDdh1c的基本 url（在消除所有重定向 url 之后）时，我得到了以下 url http://www.cbtrends.com/作为基本网址。请参阅下面的日志文件

为什么相同的 url 在浏览器和 python 程序中表现不同。我应该在 python 程序中更改什么以便它可以重定向到正确的 url？我想知道这种奇怪的行为是如何发生的。？

我观察到类似行为的其他网址是

  1. http://bit.ly/bEKyOx ====> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=150413977509 （通过浏览器）

  2. http://www.ebay.com（通过python程序）

          maxattempts = 5
      turl = url
      while (maxattempts  >  0) :               
        host,path = urlparse.urlsplit(turl)[1:3]
        if  len(host.strip()) == 0 :
           return None

        try: 
                connection = httplib.HTTPConnection(host,timeout=10)
                connection.request("HEAD", path)
                resp = connection.getresponse()                      
        except:                         
                 return None                     
        maxattempts = maxattempts - 1
        if (resp.status >= 300) and (resp.status <= 399):
            self.logger.debug("The present %s is a redirection one" %turl)
            turl = resp.getheader('location')
        elif (resp.status >= 200) and (resp.status <= 299) :
            self.logger.debug("The present url %s is a proper one" %turl)
            return turl
        else :
            #some problem with this url
            return None               
      return None

日志文件供您参考 

2010-02-14 10:29:43,260 - paypallistener.views.MrCrawler - INFO - Bringing down the base URL
2010-02-14 10:29:43,261 - paypallistener.views.MrCrawler - DEBUG - what is the url=http://bit.ly/cDdh1c
2010-02-14 10:29:43,994 - paypallistener.views.MrCrawler - DEBUG - The present http://bit.ly/cDdh1c is a redirection one
2010-02-14 10:29:43,995 - paypallistener.views.MrCrawler - DEBUG - what is the url=http://www.cbtrends.com/get-product.html?productid=reFfJcmpgGt95hoiavbXUAYIMP7OfiQn0qBA8BC7%252BV8%253D&affid=arnishad&tid=arnishad&utm_source=twitterfeed&utm_medium=twitter
2010-02-14 10:29:44,606 - paypallistener.views.MrCrawler - DEBUG - The present http://www.cbtrends.com/get-product.html?productid=reFfJcmpgGt95hoiavbXUAYIMP7OfiQn0qBA8BC7%252BV8%253D&affid=arnishad&tid=arnishad&utm_source=twitterfeed&utm_medium=twitter is a redirection one
2010-02-14 10:29:44,607 - paypallistener.views.MrCrawler - DEBUG - what is the url=http://www.cbtrends.com/
2010-02-14 10:29:45,547 - paypallistener.views.MrCrawler - DEBUG - The present url http://www.cbtrends.com/ is a proper one
http://www.cbtrends.com/
4

2 回答 2

1

您的问题是，当您调用 urlsplit 时，您的路径变量仅包含路径并且缺少查询。

因此，请尝试：

import httplib
import urlparse

def getUrl(url):
    maxattempts = 10
    turl = url
    while (maxattempts  >  0) :               
        host,path,query = urlparse.urlsplit(turl)[1:4]
        if  len(host.strip()) == 0 :
            return None
        try: 
            connection = httplib.HTTPConnection(host,timeout=10)
            connection.request("GET", path+'?'+query)
            resp = connection.getresponse()
        except:                         
            return None                     
        maxattempts = maxattempts - 1
        if (resp.status >= 300) and (resp.status <= 399):
            turl = resp.getheader('location')
        elif (resp.status >= 200) and (resp.status <= 299) :
            return turl
        else :
            #some problem with this url
            return None               
    return None
print getUrl('http://bit.ly/cDdh1c')
于 2010-02-14T17:22:53.703 回答
1

您的问题来自这一行：

host,path = urlparse.urlsplit(turl)[1:3]

您忽略了查询字符串。因此，在您提供的示例日志中，HEAD您将执行的第二个请求将在http://www.cbtrends.com/get-product.html没有 GET 参数的情况下进行。在浏览器中打开该 URL，您会看到它重定向到http://www.cbtrends.com/.

您必须使用返回的元组的所有元素来计算路径urlsplit。

parts = urlparse.urlsplit(turl)
host = parts[1]
path = "%s?%s#%s" % parts[2:5]
于 2010-02-14T17:53:38.477 回答