[ python-Bugs-1163401 ] uncaught AttributeError deep in urllib

[SourceForge.net]

Bugs item #1163401, was opened at 2005-03-14 16:39
Message generated for change (Comment added) made by lohnk
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1163401&group_id=5470

Category: Extension Modules
Group: Python 2.4
Status: Open
Resolution: None
Priority: 5
Submitted By: K Lars Lohn (lohnk)
Assigned to: Nobody/Anonymous (nobody)
Summary: uncaught AttributeError deep in urllib

Initial Comment:
Python 2.4 and Python 2.3.4 running under Suse 9.2

We're getting an AttributeError exception "AttributeError: 'NoneType' object has no attribute 'read'" within a very simple call to urllib.urlopen.

This was discovered while working on Sentry 2, the new mirror integrity checker for the Mozilla project.  We try to touch hundreds of URLs to make sure that the files are present on each of the mirrors.  One particular URL kills the call to urllib.urlopen: http://mozilla.mirrors.skynet.be/pub/ftp.mozilla.org/firefox/releases/1.0/win32/en-US/Firefox%20Setup%201.0.exe
This file probably does not exist on the mirror, however, in other cases of bad URLs, we get much more graceful failures when we try to read from the object returned by urllib.urlopen.

>>> import urllib
>>> urlReader = urllib.urlopen("http://mozilla.mirrors.skynet.be/pub/ftp.mozilla.org/firefox/releases/1.0/win32/en-US/Firefox%20Setup%201.0.exe")
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
  File "/usr/local/lib/python2.4/urllib.py", line 77, in urlopen
    return opener.open(url)
  File "/usr/local/lib/python2.4/urllib.py", line 180, in open
    return getattr(self, name)(url)
  File "/usr/local/lib/python2.4/urllib.py", line 305, in open_http
    return self.http_error(url, fp, errcode, errmsg, headers)
  File "/usr/local/lib/python2.4/urllib.py", line 322, in http_error
    return self.http_error_default(url, fp, errcode, errmsg, headers)
  File "/usr/local/lib/python2.4/urllib.py", line 550, in http_error_default
    return addinfourl(fp, headers, "http:" + url)
  File "/usr/local/lib/python2.4/urllib.py", line 836, in __init__
    addbase.__init__(self, fp)
  File "/usr/local/lib/python2.4/urllib.py", line 786, in __init__
    self.read = self.fp.read
AttributeError: 'NoneType' object has no attribute 'read'

The  attached file is a three line scipt that demos the problem.



----------------------------------------------------------------------

>Comment By: K Lars Lohn (lohnk)
Date: 2005-03-15 08:50

Message:
Logged In: YES 
user_id=1239273

This problem is apparently transient depending on network conditions or, perhaps, the configuration of the server end.  On 3/14 the problem has mysteriously vanished....

----------------------------------------------------------------------

Comment By: Jarek Zgoda (zgoda)
Date: 2005-03-15 01:52

Message:
Logged In: YES 
user_id=92222

No such error on Windows:
Python 2.4 (#60, Nov 30 2004, 11:49:19) [MSC v.1310 32 bit
(Intel)] on win32

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1163401&group_id=5470