in urllib2.py:

line 502 should be:
... user_pass = base64.encodestring('%s:%s' % (unquote
(user), unquote(password))).strip()

the '.strip()' is missing in the current version ("2.1").

this makes an additonal '\n' at the end of user_pass.
So there will be an empty line in the http header, which 
is buggy.

(see also line 645, where the .strip() is right in place!).

Best regards,

Christoph

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The change was introduced by revision 1.32 of the file, from
patch 527518. There's no mention of removing strip() there,
so I suspect it was an accident.

The strip() is still missing in CVS HEAD. I can see the
problem, in theory (base64.encodestring returns a string
with a terminating newline). However, I cannot reproduce the
problem.

Can the original poster provide a means of verifying the
problem? It may be useful as a test case.

Regardless, the change seems harmless, and can probably be
applied. I attach a patch against CVS HEAD:

--- urllib2.py.orig	2005-01-09 05:51:49.000000000 +0000
+++ urllib2.py	2005-01-29 21:31:49.000000000 +0000
@@ -582,7 +582,8 @@
             if ':' in user_pass:
                 user, password = user_pass.split(':', 1)
                 user_pass = base64.encodestring('%s:%s' %
(unquote(user),
-                                                          
unquote(password)))
+                                                          
unquote(password))
+							   ).strip()
                 req.add_header('Proxy-authorization',
'Basic ' + user_pass)
         host = unquote(host)
         req.set_proxy(host, type)

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I've run into the same bug so allow me to comment.

client environment: windows XP
target: Apache/1.3.33 (Unix)

checked on: python 2.3.4, 2.3.5, 2.4.1

To reproduce:

# from urllib2 import ...
proxy = {"http":"http://user:pwd@proxy:port"}
opener =build_opener(ProxyHandler(proxy))
install_opener( opener )

req = Request(coolurl)
# construct 
base64string = base64.encodestring('%s:%s' % (site_user,
site_pwd))[:-1]
authheader =  "Basic %s" % base64string
req.add_header("Authorization", authheader)
urlopen( req )

Symptoms: authentication failed on coolurl (HTTPError 401)
Fix: Applying the patch solves the problem for me

It appears as if the receiving server treats the empty line
as the end of the header even though it strictly shouldn't.

HTH
Pieter

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Thanks for the report, committed as Lib/urllib2.py r1.85,
r1.77.2.2.