[ZODB-Dev] Convert a ZODB 3.2 -> ZODB 3.3

Christian Robottom Reis kiko at async.com.br
Thu Oct 7 09:57:51 EDT 2004


On Thu, Oct 07, 2004 at 09:31:20AM -0400, Chris Cioffi wrote:
> I've got a stand alone ZODB app.  I can create new file storage files
> no problem, but now I need to access the data from an older v3.2 file
> storage file and I'm getting the error:
> 
> No handlers could be found for logger "ZODB.FileStorage"
> C:\Python23\Lib\site-packages\Persistence\__init__.py:25: UserWarning:
> Couldn't import the ExtensionClass-based base class
> ...

Well, it seems you have an ExtensionClass-based class stored in it. I
haven't actually run into this problem myself but I understand you might
have. 

I'm not sure how to advise you here; Tim probably knows more about this
than I do. I can explain what the problem is though: one or more
instances saved in your ZODB file inherits from Persistence.Persistent
(hardly surprising), and Persistent is gone from 3.3, replaced by a
non-ExtensionClass-based Persistent class.

(I'm going to stop now because my next suggestion is going to be
manipulating raw pickles and seeing if things break.)

Take care,
--
Christian Robottom Reis | http://async.com.br/~kiko/ | [+55 16] 3361 2331


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