Hi folks,

I'm writing an application that takes multiple file uploads on a page. I
discovered that the naming of uploaded files is based on a timestamp,
and can only ensure unique filenames if no more than one file is
uploaded per second. In my case, this isn't true: I may be uploading two
or three files at time, in which case the first is overwritten by the
second, and the second is overwritten by the third.

I tackled the problem by adding a 'counter' iterator, that tacks a
unique number on the end of every filename. This should guarantee
uniqueness. Though it's not threadsafe; maybe I should have tossed the
thread id in there as well... ;-)

-- Graham


diff P:\Quixote-0.6b5\upload.py S:\quixote\upload.py
24a25,36
 > class _counter:
 >     """
 >     Yield x for x in the set of naturals.
 >     A generator would be simpler, but reverse-incompatible.
 >     """
 >     def __init__(self):
 >         self.c = 0
 >     def next(self):
 >         self.c += 1
 >         return str(self.c)
 >
 > counter = _counter()
154,156c166,167
<         tstamp = (strftime("%Y%m%d.%H%M%S", localtime(now)) +
<                   ("%.3f" % (now % 1))[1:])
<         filename = "upload.%s.%s" % (tstamp, os.getpid())
---
 >         tstamp = strftime("%Y%m%d.%H%M%S", localtime(now))
 >         filename = "upload.%s.%s.%s" % (tstamp, os.getpid(),
counter.next())