有没有一种简单的方法可以在python中请求URL而不遵循重定向？

Looking at the source of urllib2 it looks like the easiest way to do it would be to subclass HTTPRedirectHandler and then use build_opener to override the default HTTPRedirectHandler, but this seems like a lot of (relatively complicated) work to do what seems like it should be pretty simple.

Here is the Requests way:

import requests
r = requests.get('http://github.com', allow_redirects=False)
print(r.status_code, r.headers['Location'])

Dive Into Python has a good chapter on handling redirects with urllib2. Another solution is httplib.

>>> import httplib
>>> conn = httplib.HTTPConnection("www.bogosoft.com")
>>> conn.request("GET", "")
>>> r1 = conn.getresponse()
>>> print r1.status, r1.reason
301 Moved Permanently
>>> print r1.getheader('Location')
http://www.bogosoft.com/new/location

This is a urllib2 handler that will not follow redirects:

class NoRedirectHandler(urllib2.HTTPRedirectHandler):
    def http_error_302(self, req, fp, code, msg, headers):
        infourl = urllib.addinfourl(fp, headers, req.get_full_url())
        infourl.status = code
        infourl.code = code
        return infourl
    http_error_300 = http_error_302
    http_error_301 = http_error_302
    http_error_303 = http_error_302
    http_error_307 = http_error_302

opener = urllib2.build_opener(NoRedirectHandler())
urllib2.install_opener(opener)

The redirections keyword in the httplib2 request method is a red herring. Rather than return the first request it will raise a RedirectLimit exception if it receives a redirection status code. To return the inital response you need to set follow_redirects to False on the Http object:

import httplib2
h = httplib2.Http()
h.follow_redirects = False
(response, body) = h.request("http://example.com")

i suppose this would help

from httplib2 import Http
def get_html(uri,num_redirections=0): # put it as 0 for not to follow redirects
conn = Http()
return conn.request(uri,redirections=num_redirections)

I second olt’s pointer to Dive into Python. Here’s an implementation using urllib2 redirect handlers, more work than it should be? Maybe, shrug.

import sys
import urllib2

class RedirectHandler(urllib2.HTTPRedirectHandler):
    def http_error_301(self, req, fp, code, msg, headers):  
        result = urllib2.HTTPRedirectHandler.http_error_301( 
            self, req, fp, code, msg, headers)              
        result.status = code                                 
        raise Exception("Permanent Redirect: %s" % 301)

    def http_error_302(self, req, fp, code, msg, headers):
        result = urllib2.HTTPRedirectHandler.http_error_302(
            self, req, fp, code, msg, headers)              
        result.status = code                                
        raise Exception("Temporary Redirect: %s" % 302)

def main(script_name, url):
   opener = urllib2.build_opener(RedirectHandler)
   urllib2.install_opener(opener)
   print urllib2.urlopen(url).read()

if __name__ == "__main__":
    main(*sys.argv) 

The shortest way however is

class NoRedirect(urllib2.HTTPRedirectHandler):
    def redirect_request(self, req, fp, code, msg, hdrs, newurl):
        pass

noredir_opener = urllib2.build_opener(NoRedirect())