Zope FTP Server is broken in Zope 2.12/Python 2.6 due to asyncore change

[David Glick]

When running Zope 2.12 (current svn checkout) on Python 2.6, attempting to connect via FTP results in the following traceback:

2009-08-24 22:38:17 INFO ZServer Incoming connection from 127.0.0.1:50099
2009-08-24 22:38:17 ERROR ZServer uncaptured python exception, closing channel <ZServer.FTPServer.FTPServer listening 127.0.0.1:8021 at 0x202d0f8> (<type 'exceptions.AttributeError'>:'collections.deque' object has no attribute 'push' [/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/asyncore.py|read|74] [/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/asyncore.py|handle_read_event|408] [/Users/davidg/ONENW/plonedev-4.0/src/Zope2/src/ZServer/FTPServer.py|handle_accept|666] [/Users/davidg/ONENW/plonedev-4.0/src/Zope2/src/ZServer/FTPServer.py|__init__|92] [/Users/davidg/ONENW/plonedev-4.0/src/Zope2/src/ZServer/medusa/ftp_server.py|__init__|101] [/Users/davidg/ONENW/plonedev-4.0/src/Zope2/src/ZServer/medusa/ftp_server.py|respond|244] [/Users/davidg/ONENW/plonedev-4.0/src/Zope2/src/ZServer/FTPServer.py|push|113])
2009-08-24 22:38:17 WARNING ZServer unhandled close event

This appears to be related to the fact that ZServer.FTPServer's zope_ftp_channel class overrides the 'push' method which would otherwise be inherited from asynchat.async_chat (via ZServer.medusa.ftp_server's ftp_channel class) -- but the implementation of asynchat changed in Python 2.6 to use a collections.deque instance as its producer_fifo, instead of a custom class wrapping deque, so the 'push' implementation in ZServer.FTPServer.zope_ftp_channel is now wrong for Python 2.6.

[Andreas Jung (ajung)]

This is a blocker for the 2.12 final release

[Andreas Jung (ajung)]

I assume we need two variants of the push() methods: one for Python 2.5 (existing code) and a new one for Python 2.6 :->

[Andreas Jung (ajung)]

Fixed on the Zope trunk and 2.12 branch:

http://svn.zope.org/Zope/trunk/?rev=103395&view=rev
http://svn.zope.org/Zope/branches/2.12/?rev=103397&view=rev

There are no tests (except real-world tests) for this change since I don't know how to unittest this properly.

[David Glick (davisagli)]

Fix confirmed with Python 2.6 -- thanks Andreas!

[Tres Seaver (tseaver)]

I don't know why this assignment got made: this tracker is not monitored by the Python developers, AFAIK. At any rate, they have already said this is "WONTFIX" on the Python side. See the thread here:

 http://mail.python.org/pipermail/python-dev/2009-March/086668.html

[R. David Murray (rdmurray)]

On Tue, 09 Feb 2010 18:34:45 +0000, Tres Seaver wrote:
> I don't know why this assignment got made: this tracker is not
> monitored by the Python developers, AFAIK. At any rate, they have

FYI I've started to monitor the python tracker, but whether I'll
have time to do anything with what shows up is a different
question :)

--
R. David Murray www.bitdance.com