[albatross-users] cookie error in sessionfile.py

[Sheila King]

Today I asked some of the members on my team to test the application I've 
been building. It doesn't do a whole lot yet. Mostly authentication stuff. 
Create new account. Log in. Log out. Request lost password. Expires after x 
minutes of inactivity.

Anyhow, I had tested it on Mozilla 1.3 and 1.0 and IE 5.0 and 6.0 on two 
different computers. Never a problem with loading templates and simply 
displaying pages.

So I show it to my boss today and first thing, as soon as she goes to the 
URL, she gets a traceback. And I look and tell her it is a cookie thing, 
and she has them enabled and she fiddled around with her browser, and no 
matter what, she couldn't view the app. Just errors and tracebacks. Here is 
a sample traceback:

----------------------------------------
Template traceback (most recent call last):
Traceback (most recent call last):
  File "/usr/lib/python2.2/site-packages/albatross/app.py", line 142, in run
    self.load_session(ctx)

  File "/usr/lib/python2.2/site-packages/albatross/app.py", line 204, in 
load_session
    ctx.load_session()
  File "/usr/lib/python2.2/site-packages/albatross/sessionfile.py", line 
46, in load_session
    sesid = self._get_sesid_from_cookie()

  File "/usr/lib/python2.2/site-packages/albatross/sessionfile.py", line 
37, in _get_sesid_from_cookie
    return os.path.basename(c[self.app.ses_appid()].value)
  File "/usr/lib/python2.2/UserDict.py", line 14, in __getitem__
    def __getitem__(self, key): return self.data[key]
KeyError: appid
------------------------------------------

In an attempt at resolving this situation, I made the following change in 
the sessionfile.py file:

To this function:

(starting at line 32)
------------------------------------------
    def _get_sesid_from_cookie(self):
        hdr = self.request.get_header('Cookie')
        if hdr:
            c = Cookie.SimpleCookie(hdr)
            try:
                return os.path.basename(c[self.app.ses_appid()].value)
            except OSError:
                pass
        return None

------------------------------------------
I simply added one more exception check:

------------------------------------------
    def _get_sesid_from_cookie(self):
        hdr = self.request.get_header('Cookie')
        if hdr:
            c = Cookie.SimpleCookie(hdr)
            try:
                return os.path.basename(c[self.app.ses_appid()].value)
            except OSError:
                pass
            ### KeyError fix
            except KeyError:
                pass
        return None
------------------------------------------

and that seems to have solved the problem. By the way, I had two other 
people test the app before I made the fix, and they had no problems either.

The person with the issue was using IE 5.5, but two of the other testers 
also used that browser, and had no issues.

FWIW, it seems that her browser was sending a cookie. How, I have no idea? 
To my knowledge, this person has never before visited the site/directory 
where my app was stored. Anyhow, her browser was sending a cookie, but not 
one my app had set, and then my app was trying to lookup the cookie by the 
appid name, and failing.

So, I just old the app to ignore a KeyError, and it all seems fixed?
-- 
Sheila King
http://www.thinkspot.net/sheila/
http://www.k12groups.org