[Zope] Upgrade to 2.5.0 breaks site: TypeError: object of type 'string' is not callable

[Gregor Hoffleit]

I'm running into strange trouble with one site when I try to upgrade it
from Zope 2.4 to 2.5.0.

With 2.4 (up to 2.4.4b1), the site works fine. Now when I upgrade Zope
to 2.5.0 (or 2.5.1b1), I get an "TypeError: object of type 'string' is not
callable" whenever I try to access the site (see below).

Furthermore, running the Data.fs ZODB with 2.5.x once seems to corrupt
it! I.e. when I move back the Data.fs to 2.4.4b1 (where it had worked
before), it suddenly fails with the same error!


This is the error message:

    Site Error

    An error was encountered while publishing this resource.

    TypeError
    Sorry, a site error occurred.

    Traceback (innermost last):
      File /tmp/z/Zope-2.5.1b1-src/lib/python/ZPublisher/Publish.py, line 150, in publish_module
      File /tmp/z/Zope-2.5.1b1-src/lib/python/ZPublisher/Publish.py, line 114, in publish
      File /tmp/z/Zope-2.5.1b1-src/lib/python/Zope/__init__.py, line 159, in zpublisher_exception_hook
	(Object: MyOwnSite)
      File /tmp/z/Zope-2.5.1b1-src/lib/python/ZPublisher/Publish.py, line 89, in publish
      File /tmp/z/Zope-2.5.1b1-src/lib/python/ZPublisher/BaseRequest.py, line 247, in traverse
      File /tmp/z/Zope-2.5.1b1-src/lib/python/ZPublisher/BeforeTraverse.py, line 99, in __call__
    TypeError: object of type 'string' is not callable


The output is the same for any path I try. The ZMI
(http://localhost:8080/manage) also fails with this error.



The output of starting Zope (see below) doesn't show anything
suspicious. I have no idea what could cause this problem, and how I
could try to track down the problem.





Below I attach the output of starting Zope in debug mode.




The output of starting 2.4.4b1 (which works fine) in debug mode:

------
2002-03-06T13:19:01 PROBLEM(100) ZODB Could not import class 'Connection' from module 'Products.ZMySQLDA.DA'
/tmp/z/Zope-2.4.4b1-src/lib/python/SearchIndex/__init__.py:91: DeprecationWarning: The usage of the SearchIndex package is deprecated since Zope 2.4.
This package is only kept for backwards compatibility for a while
and will go away in a future release.

Please use instead the re-factored modules in Products/PluginIndexes.

  warnings.warn("The usage of the SearchIndex package is deprecated since \
------
2002-03-06T13:19:12 INFO(0) ZServer HTTP server started at Wed Mar  6 14:19:12 2002
	Hostname: clapton
	Port: 8081
------
2002-03-06T13:19:12 INFO(0) ZServer FTP server started at Wed Mar  6 14:19:12 2002
	Hostname: clapton
	Port: 8022




The output of starting 2.5.1b1 (which doesn't work) in debug mode:

------
2002-03-06T13:24:52 PROBLEM(100) ZODB Could not import class 'Connection' from module 'Products.ZMySQLDA.DA'
------
2002-03-06T13:24:52 INFO(0) ZODB Opening database for mounting: '142567176_1015421092.553436'
------
2002-03-06T13:24:52 INFO(0) ZODB Mounted database '142567176_1015421092.553436' at /temp_folder
------
2002-03-06T13:25:01 INFO(0) Zope New disk product detected, determining if we need to fix up any ZClasses.
------
2002-03-06T13:25:02 INFO(0) ZServer HTTP server started at Wed Mar  6 14:25:02 2002
	Hostname: clapton
	Port: 8081
------
2002-03-06T13:25:02 INFO(0) ZServer FTP server started at Wed Mar  6 14:25:02 2002
	Hostname: clapton
	Port: 8022