Get the referer view of a request

# -*- coding: utf-8 -*-
#
# Copyright (c) 2009 Arthur Furlan <[email protected]>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# On Debian systems, you can find the full text of the license in
# /usr/share/common-licenses/GPL-2

import re

def get_referer_view(request, default=None):
    ''' 
    Return the referer view of the current request

    Example:

        def some_view(request):
            ...
            referer_view = get_referer_view(request)
            return HttpResponseRedirect(referer_view, '/accounts/login/')
    '''

    # if the user typed the url directly in the browser's address bar
    referer = request.META.get('HTTP_REFERER')
    if not referer:
        return default

    # remove the protocol and split the url at the slashes
    referer = re.sub('^https?:\/\/', '', referer).split('/')
    if referer[0] != request.META.get('SERVER_NAME'):
        return default

    # add the slash at the relative path's view and finished
    referer = u'/' + u'/'.join(referer[1:])
    return referer